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Matti Heikkilä, CTO of MetGen: A clear path ahead of the bioeconomy– Expert opinion in European Biotechnology Life Science and Industry Magazine, 2017

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A clear path ahead for the bioeconomy

There’s no way around it: renewables are the future, Matti Heikkilä believes. European Biotechnology talked to the CTO of Finnish bioeconomy company MetGen about what bio-based products need to bring to the table to usurp their fossil-based counterparts.

European Biotechnology 
Matti, you say we need to stop using fossil fuels. But right now there hardly seems to be a consensus on that – especially among politicians. Are you sure this is going to happen in our lifetimes?
Matti Heikkilä
It is hard to be sure about such things – there are sometimes political decisions that defy logic and reason. But I most certainly hope so! I think the key there is to stop wishing it will happen and work towards that goal, by making renewable fuels and chemicals and good alternatives a viable choice for the oil-based industry. In fact, I already see the transition happening. There are big industries, in pulp and paper and packaging, and they all, especially in Europe, seem to share the vision that the chemicals and the materials that are made of oil today can be replaced and, in some cases, even better materials can be found using renewable resources.

European Biotechnology 
Has Europe advanced further down the path towards a bioeconomy?
There is a much greater political will going in this direction, especially when compared with what is happening in the US. There are more market-driven approaches on the other side of the Atlantic, but I think there are not as many political drivers to go towards green objectives. Another benefit that we have in Europe is the strong co-operation that stems from the programmes like Horizon 2020, which puts together the best experts from both academia and the industry working towards common goals. This is getting much better nowadays – it’s a much more open and cross-disciplinary collaboration than it was before. One reason for this is: it’s a much more market-driven approach. People are sharing their information with their own benefit in mind. If they make the whole value chain work, it enables their business.

European Biotechnology 
So it is all about the value chains?
Absolutely. For example, at MetGen, we have created an enzyme that is very good at converting the sugars in wood even at lower purity levels, just to help the value chain. It does not take anything away from us that the pre-treatment company makes a good pre-treated wood slurry as the substrate for our enzymes; and if a chemical company can then turn the result into a plastic bottle, that is also good for our business. It is all about collaboration to fix these value chains. So can we replace petrol-based chemicals in our lifetime? I believe we can do it much faster. Most of the technology already exists, and it is just a matter of connecting the dots, and the right capabilities and people.

European Biotechnology
How does Finland compete within the European bioeconomy?

Finland’s resources are almost all wood – similar to our Scandinavian neighbours, but different from many European countries. Even in the European-wide bioeconomy strategy, there are separate sections for different countries because the national capabilities and resources are so different. In Germany and the Netherlands, for example, the focus is heavily on biochemicals. The bioeconomy is driven by the industry that is strong locally. The same is true for Finland. Forestry and pulp and paper drives the bioeconomy relatively heavily here. At the same time, since we are up in the North, we do not have the same productivity when it comes to agriculture. We have the bioeconomy strategy implemented on the government level, and it also focusses on the wood-based biomasses. Our company, MetGen, also concentrates on those materials for the most part.

European Biotechnology 
Isn’t it risky to rely on one resource only?
Actually, MetGen is not picky about the biomass. Wood is where our expertise really shines because that’s the harder substrate. As a rule of thumb, the more lignin you have, the harder it is to put it to economic use. However, the more we assess it, the more we realise that wood is actually a great resource. Wood is not really that expensive. It is also in year-round supply, while grass or straw need to be stored somehow, which then leads to practical issues that come with storing, like the risk of fire and the need for storage space. Also, wood has a lot of sugars to it. Eighty percent of it is sugar – you just need to know how to crack it. And not least, the supply chain is already there. Wood is already being utilised in large quantities. So to me, it is just about transitioning towards using bio­chemicals. MetGen aims to provide the new technologies for pulp and paper to do that.

European Biotechnology
How exactly do you do that?
Let me give you an example. We were requested to come up with a laccase that could survive a pH of 10 to 11, or even be at an optimum in this range, so that it could be used in Kraft pulping to help the bleachability and de­lignification of that process. The company that requested this hardly thought it was possible, but we agreed to give it a try. And five months later, we had that molecule industrially produced. And while it was requested by a single company, it now benefits the entire industry.

European Biotechnology
What role does the consumer play? Can bio-based products only succeed if there is a demand for environmentally friendly alternatives?
Not at all! The funny thing is: the Polyethylene Furanoate, or PEF for short, is not actually biodegradable. But it is a better alternative to PET. It is a better packaging material; it has better barrier properties than oil-based alternatives; it makes the beverage have a better shelf-life – the oxygen stays out and the carbonation stays in. So in a first step, it might not replace PET-bottles, but it is replacing aluminium cans and glass bottles. Because it has the same superior properties as those. Later, it will overtake the other plastic packaging. So the green alternative is actually better than we can get out of oil. And that’s the thing: For a bio-based alternative to succeed, it has to be as good as the petrol-based product but cheaper, or the same price but better.

European Biotechnology
So what is needed for the bioeconomy to come out on top?
What is needed for that to happen is us in Europe starting to put down money and investment on piloting and market demonstration of technologies. We use a lot of resources and money on research, but then we fail to finance the commercialisation of those technologies. The same is not true of the Chinese or the Americans. We use roughly 90 percent of our resources on research and the remaining ten on development. The same numbers in the US are roughly fifty-fifty, and in China, they use more money on the development and scale-up and commercialisation of things than research. So, what happens in a globalised world is that we use taxpayer money here in Europe to create good products, and then we end up selling them to other continents. My second point is the brain leak if you will. We have to make sure we have incentives for experts globally to come to Europe and help us solve these value chain-wide challenges I mentioned. Europe cannot be the place where we start building walls. Every expert that we get, no matter from what country, will create more work around themselves. So we should not be afraid of losing our jobs if foreign experts come over. Rather, we should be giving them incentives to come. Right now, people are moving away from Finland, and from Europe, to other places where there are more incentives for the brightest and the best of us to succeed. We really need them here.

Matti Heikkilä is Chief Technology Officer of Finnish bioeconomy company MetGen Oy, which develops enzymatic solutions for processing lignocellulosic biomass. Last year, MetGen won the John Sime Award for Most Innovative New Technology at the European Forum for Industrial Biotechnology and the Bioeconomy (EFIB). Heikkilä has more than a decade of experience in European industrial biotechnology.

Finnish MetGen wins the John Sime Award for biotechnology

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Finnish enzyme producer MetGen won the John Sime Award for Most Innovative New Technology at the European Forum for Industrial Biotechnology and the Bioeconomy (EFIB). Along with several other enterprises in its industry, MetGen – already a leading Finnish bioeconomy company – is now pursuing strong international growth.

MetGen, which produces customised industrial enzymes particularly for the processes of the pulp and paper industry, has won the John Sime Award for Most Innovative New Technology at the European Forum for Industrial Biotechnology and the Bioeconomy (EFIB). The winner was selected by the Forum’s participants, comprised of biotechnology professionals, investors and decision-makers, among others.

“Small companies like us in the biotechnology sector do accept even great challenges and, thereby, risks, in their quest to change the world. We are also taking the industrial sector in a more sustainable direction and pointing the way for large-scale operators. It is important for us to be open to cooperation and find skillful partners. Our open-minded approach and our team’s consummate competence appealed to the Forum’s audience, and we are genuinely flattered by the award. I believe that the award will help us to find partners,” says MetGen’s Chief Technology Officer Matti Heikkilä.

The enzymes tailored by MetGen speed up processes in the pulp and paper industry, generating considerable savings in energy and raw materials. According to Heikkilä, the company is now aiming at strong international growth.

“We have just launched sales in our main market and will now aim to scale this into larger growth. Finpro’s help and knowledge on networking and entering new export markets has been very important for us. Finland possesses a vast amount of first-rate biotechnology know-how, but no-one is going to come over here and carry us away. Rather, we have to be bold, enter the international arena together and make ourselves known,” says Heikkilä.

Opening up the bottlenecks in the growth of bioeconomy companies

Thanks to large-scale operators in the pulp and paper industry, the bioeconomy has a long tradition in Finland. New technologies and increasingly strict regulations have opened up plenty of new bioeconomy opportunities, which are being seized particularly eagerly by innovative small and medium-sized enterprises. Pia Qvintus, who heads Finpro’s Innovative Bioproducts Growth Program as a Program Manager, is indeed of the opinion that Finland also has a number of other small companies that represent innovative, first-rate competence and now find themselves in a similar situation to MetGen.

“Companies in the bioeconomy industry have developed new ways to create value-added products as well as energy and resource-efficient processes and technologies for their customers. These companies are in a growth phase and share challenges involving the start-up of production, for example, as well as financing and international growth. The companies’ own resources are largely tied up in product development and production, due to which they are not necessarily able to build international partnerships and sales on their own in several markets in the long term. Finpro’s programme aims to help companies overcome such challenges and to introduce new solutions created by the Finnish bioeconomy abroad,” outlines Pia Qvintus.

Finpro’s Innovative Bioproducts Growth Program includes 17 other companies in addition to MetGen. One of these is Paptic, which has developed a recyclable, bio-based and biodegradable, wood fibre-based material. The first commercial application of this material involves a replacement for plastic bags. Demand for Paptic’s product has increased as a result of the bans and restrictions on plastic bags that are becoming increasingly widespread in various countries.

For further information, please contact:
Pia Qvintus, Program Manager for the Innovative Bioproducts Growth Program, Finpro +358 50 563 4129,

Matti Heikkilä, Chief Technology Officer, MetGen Oy, +358403540701,

Hetta Huittinen, Communications Manager, Finpro, +358 40 033 9597,

Finpro helps Finnish SMEs go international, encourages foreign direct investment in Finland and promotes tourism. Finpro comprises Export Finland, Visit Finland and Invest in Finland. Finpro is a public sector operator with 240 experts serving in 37 export centres in 31 countries and 6 regional offices in Finland.
Finpro – Growth for Finland

As a partner of Team Finland, Finpro manages nearly 40 significant growth programmes, such as Cleantech Finland, Food from Finland and FinlandCare. These growth programmes allow Team Finland to help hundreds of Finnish companies go international and attract foreign investments in Finland.


3Fbio and MetGen revealed as Bio-based Winners at #EFIB2016, Glasgow, Scotland, UK

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3F Bio and MetGen were both acknowledged by their peers as Industrial Biotech leaders at this year’s European Forum on Industrial Biotechnology and the Bioeconomy, #EFIB2016.

3F Bio, a technology spin-out company from University of Strathclyde, was voted strongest proposal for funding by a panel of venture capitalists, including BASF VC, S’InvesTec LLC, Sofinnova Partners, Emerald Technology Ventures and Capricorn Venture Partners, at EFIB’s first ever ‘pitchfest’.   3FBio won the pitch for their potential to transform the production economics of mycoprotein (commonly known by the brand name Quorn™) through integrated production within existing large scale biorefineries.  Their process delivers both conversion cost efficiencies through a zero-waste process alongside the current production of bioethanol and high protein livestock feed, and unlocks capital efficiency by simplifying fermentation technology.  Commenting on the win, CEO Jim Laird said: “3f’s innovative approach for zero waste integrated fermentation provides a strong solution to the challenge of meeting the protein requirements for an ever growing global population.  This area is receiving global market interest, and with an aim to halve the conversion cost of mycoprotein, 3f’s approach provides a global food solution with exception sustainability benefits, demonstrating the merits of industrial biotech.  We are delighted to have participated in pitchfest, excited by the range of interest and quality of new contacts from EFIB, and enthused by the reaction from both potential investors and partners.”)

MetGen received the coveted John Sime Award for best innovation presentation for their progress in designing enzymatic processes to unlocking the potential of wood and forestry residues as a future feedstocks for bio-based products.  CEO Alex Michine, who was presented with his Award by Roger Kilburn, CEO of IBioIC and Joanna Dupont-Inglis, Director of Industrial Biotech at EuropaBio said ‘We believe it is a necessity for industries move towards renewable feed stocks. It is a massive change that will create an enormous new market, in which the existing supply-chains of renewable feed stock – such as pulp and paper industry – will have a lot of common interests with chemical, energy, and other manufacturing industries. MetGen addresses challenges in all of these areas while maintaining a laser-focus on technical side. Companies like ours are needed function as the catalyst of this change. Apart from our capabilities in enabling new and better end-products, I think it was this message that resonated with the audience. We like to collaborate in order to have impact on larger scale of things, and this award is an excellent reminder that there are plenty of potential partners who are well motivated to work towards the same objectives. We find this encouraging and it motivates us to keep the pace.’

EuropaBio’s Industrial Biotech Council Chair and Managing Board Member of Royal DSM concluded, ‘EFIB is now well known as the ‘must attend’ EU event showcasing cutting edge innovation in industrial biotechnology.  Companies like 3FBio and MetGen are working hard towards providing renewable, bio-based solutions to the challenges of feeding, fuelling and providing materials for a growing population, tackling climate change and using resources more efficiently.  We are proud to honour them with these awards in recognition of the societal, environmental and economic benefits that they will bring for people and for the environment.

Brussels 28 October 2016 


Media contact

Cosmin Popa, EuropaBio Communications and National Associations Manager

Email: / Telephone: +32 2 739 11 73 / Mobile: +32 499 906 129


About EuropaBio

EuropaBio, the European Association for Bioindustries, promotes an innovative and dynamic European biotechnology industry. EuropaBio and its members are committed to the socially responsible use of biotechnology to improve quality of life, to prevent, diagnose, treat and cure diseases, to improve the quality and quantity of food and feedstuffs and to move towards a bio-based and zero-waste economy. EuropaBio represents 77 corporate and associate members and bio regions, and 16 national biotechnology associations in turn representing over 1800 biotech SMEs.

Read more about our work at


About EFIB’s John Sime Award

Each year EFIB dedicates an award to John Sime who played a pivotal role in the early development of the congress and to recognise his commitment both to the event and to the bioeconomy.  John Sime’s own background as an R&D director for an SME ensured he was a keen advocate of new science and technology. To reflect this, an award is presented in his memory for the most innovative idea responding to societal and environmental challenges

Kaarinalainen MetGen voitti bioteknologian John Sime -palkinnon

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Finpron johtaman Innovatiiviset biotuotteet –kasvuohjelman jäsen MetGen on voittanut bioteknologian ja biotalouden EFIB-konferenssissa John Sime -palkinnon innovatiivisimmasta teknologiasta. Suomalaisten biotalousyritysten kärkeen kuuluva MetGen hakee useiden muiden alan yritysten tavoin voimakasta kansainvälistä kasvua.

Räätälöityjä teollisia entsyymejä erityisesti puu- ja paperiteollisuuden prosesseihin valmistava MetGen on voittanut eurooppalaisessa bioteknologian ja biotalouden EFIB-konferenssissa innovatiivisimmasta teknologiasta myönnettävän John Sime -palkinnon. Palkinnon valitsivat konferenssin osallistujat, jotka koostuvat muun muassa bioteknologian ammattilaisista, sijoittajista ja päättäjistä.

  • Bioteknologian alalla kaltaisemme pienet yritykset ottavat vastaan suuriakin haasteita ja sitä kautta riskejä, ja pyrkivät näin muuttamaan maailmaa. Myös me muutamme teollisuutta kestävämpään suuntaan ja näytämme suuntaa suurille toimijoille. Meille on tärkeää olla avoimia yhteistyölle ja löytää osaavia kumppaneita. Avoin asenteemme ja tiimimme piinkova osaaminen vetosi konferenssissa yleisöön ja olemme todella otettuja palkinnosta-. Uskon, että palkinto auttaa meitä edelleen kumppaneiden etsinnässä, sanoo MetGenin Chief Technology Officer Matti Heikkilä.

MetGenin räätälöimien entsyymien avulla puu- ja paperiteollisuuden prosessit nopeutuvat, josta syntyy merkittäviä säästöjä energiassa ja raaka-aineissa. Heikkilän mukaan yritys tähtää nyt kovaan kansainväliseen kasvuun.

  • Olemme juuri saaneet päämarkkinamme eli puu- ja paperiteollisuuden myynnin käyntiin ja nyt pyrimme skaalaamaan tätä laajemmaksi kasvuksi. Meille on ollut tärkeää Finpron apu ja osaaminen uusien vientimarkkinoiden avaamisessa ja verkostoitumisessa. Suomessa on valtavasti korkealaatuista bioteknologian osaamista, mutta kukaan ei tule meitä täältä hakemaan, vaan meidän täytyy yhdessä mennä rohkeasti kansainvälisille areenoille ja tehdä itsemme tunnetuksi, Heikkilä sanoo.

Finpron biotalouden toimialajohtaja Risto Huhta-Koivisto näkee panostukset innovatiivisten biotuoteyritysten kansainvälistymiseen merkittävänä mahdollisuutena koko Suomelle.

  • Biotalouden merkitys on Suomelle suuri ja toimiala tulee kasvamaan voimakkaasti myös tulevaisuudessa. Tällä hetkellä biotalous vastaa 29% Suomen BKT:sta. Suomi on laatinut kansallisen biotalousstrategian, jossa toimialalle on asetettu kunnianhimoiset tavoitteet. Jotta Suomi saavuttaa asettamansa tavoitteet, kannattaa arvoketjun alkupään ohella satsata nykyistä voimakkaammin myös korkean jalostusasteen tuotteisiin ja palveluihin. Huippuosaamiseen perustuva liiketoiminta luo vahvan talouskehityksen pohjan. Innovatiiviset biotuotteet kasvuohjelman yrityksillä on potentiaalia yli 100 M€ liikevaihtoon 3-5 vuodessa. Investointien toteutuessa työllistämisvaikutus on huomattava. On hyvin mahdollista, että muutamasta kasvuohjelman yrityksestä tulee globaalin luokan menestystarinoita, vahvistaa Huhta-Koivisto.

Biotalosyritysten kasvun pullonkauloja avataan

Biotaloudella on Suomessa suurten puu- ja paperitoimijoiden kautta pitkät perinteet. Uusien teknologioiden ja kiristyvän sääntelyn myötä biotaloudessa on avautunut paljon uusia mahdollisuuksia, joihin varsinkin innovatiiviset pk-yritykset ovat tarttuneet. Finpron Innovatiiviset biotuotteet -kasvuohjelman ohjelmapäällikkö Pia Qvintus näkeekin, että MetGenin kanssa vastaavassa tilanteessa olevia pieniä, innovatiivista huippuosaamista edustavia yrityksiä on Suomessa useita muitakin.

  • Biotalousalan yritykset ovat kehittäneet uusia tapoja luoda lisäarvoisia tuotteita sekä energia- ja resurssitehokkaita prosesseja tai teknologioita asiakkaille. Yritykset ovat kasvuvaiheessa ja niitä yhdistävät haasteet esimerkiksi tuotannon käynnistämisessä, rahoituksessa ja kansainvälisessä kasvussa. Yritysten omat resurssit on sidottu pitkälti tuotekehitykseen ja tuotantoon, eikä kansainvälisiä kumppanuuksia ja myyntiä välttämättä pystytä rakentamaan omin voimin pitkäjänteisesti useilla markkinoilla. Ohjelman tavoitteena on auttaa näissä haasteissa ja viedä suomalaisen biotalouden uusia ratkaisuja ulkomaille, kertoo Innovatiiviset biotuotteet -ohjelmapäällikkö Pia Qvintus.

Finpron Innovatiiviset biotuotteet -ohjelma auttaa suomalaisia biotalousalan yrityksiä löytämään uusia, kasvavia markkinoita erityisesti maista, joissa on oma biotalousstrategia, kuten Pohjoismaista, saksankielisestä Euroopasta, Ranskasta, Belgiasta ja muutamasta Aasian maasta. MetGenin lisäksi ohjelmassa on mukana 17 yritystä, muun muassa Paptic, joka on kehittänyt kierrätettävän, biopohjaisen ja -hajoavan sekä puukuitupohjaisen materiaalin. Tämän materiaalin ensimmäisenä kaupallisena sovelluksena on muovikassien korvaaminen. Papticin tuotteen kysyntää siivittävät jatkuvasti eri maissa yleistyvät muovikassikiellot ja -rajoitukset.

Innovatiiviset biotuotteet -ohjelma on Finpron johtama ja työ- ja elinkeinoministeriön rahoittama. Biotuotteet kuuluvat hallituksen kärkihankkeisiin.


Risto Huhta-Koivisto, toimialajohtaja, biotalous, Finpro, +358 40 343 3347,

Matti Heikkilä, Chief Technology Officer, MetGen Oy, +358403540701,

Pia Qvintus, Finpro, Innovatiiviset biotuotteet -ohjelmapäällikkö, Finpro +358 50 563 4129,

Hetta Huittinen, viestintäpäällikkö, Finpro, p. 040 033 9597,

Finpro auttaa suomalaisia pk-yrityksiä kansainvälistymään, hankkii Suomeen lisää ulkomaisia investointeja ja kasvattaa ulkomaisten matkailijoiden virtaa Suomeen. Finpron muodostavat Export Finland, Visit Finland ja Invest in Finland. Finpro on julkinen toimija, jonka 240 asiantuntijaa toimii 37 vientikeskuksessa 31 maassa ja 6 aluetoimistossa Suomessa.
Finpro – kasvua Suomeen

Team Finland -kumppanina Finpro hallinnoi lähes 40 merkittävää kasvuohjelmaa, kuten puhtaan teknologian Cleantech Finland, Food from Finland ja FinlandCare. Kasvuohjelmilla Team Finland auttaa satoja suomalaisyrityksiä kansainvälisille markkinoille ja houkuttelee investointeja maailmalta Suomeen.

BIOrescue – Press Release on New EU Project

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BIOrescue: Valorising mushroom compost to create innovative bio-based products

Pamplona, 29 September 2016 – Creating added value products from mushroom compost is the objective of the BIOrescue project which has been successfully launched today.

Mushroom production generates five million tonnes of compost each year in the European Union. This compost is currently landfilled or used for landscaping purposes even though it contains valuable organic components. In view of transforming this compost into a new income stream for mushroom producers, the BIOrescue project will develop innovative conversion processes to create bio-based products from mushroom compost.

“The technology development inherent in BIOrescue will offer great opportunities to create value from by-products from mushroom processing. This will generate significant incomes for the sector while supporting the move towards a circular economy” says Philippe Mengal, Executive Director of the Bio-based Industries Joint Undertaking in Brussels.

The project will bring together a multidisciplinary team of eleven partners comprising one large company, several SMEs, as well as two universities and two research institutions. Together, the project partners will develop a new biorefinery process that will allow the conversion of mushroom compost into innovative bio-based products such as bio-pesticides, bio-degradable nanocarriers for drug or fertilizer encapsulation and bio-based horticultural fertilizers.

By delivering innovative solutions to increase the efficiency of biomass conversion and reduce water and energy consumption, the experts involved in the project will ensure the sustainability of the novel process. To strengthen the competitiveness of the newly developed bioproducts in relation to their fossil-fuel based alternatives, project partners will assess the economic and environmental impact of the whole process.

BIOrescue is coordinated by CENER (Spanish National Renewable Energy Centre) and will be run in cooperation with 10 European partners: Monaghan Mushrooms Ireland, Universita degli studi di Napoli Frederico II, MetGen Oy, Clea Technologies, Zabala Innovation Consulting, Max-Plank Gesellschaft zur Förderung der Wissenschaften, Celignis Ltd., Imperial College of Science Technology and Medicine, C-Tech Innovation and Greenovate! Europe. This project has received funding from the Bio Based Industries Joint Undertaking under the European Union’s Horizon 2020 research and innovation programme under grant agreement No 720708.

Press and media enquiries can be directed to +32 (0)2 00 10 07.

Näyttökuva 2016-10-12 kello 14.45.21

Bioforever Press Release | Demonstration project for the conversion of woody biomass to value adding chemical building blocks

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By a consortium of 14 European companies using EU funding under the Horizon 2020 program

Brussels, September 1st   BIOFOREVER (BIO-based products from FORestry via Economically Viable European Routes) – a consortium of 14 European companies – today announced the start of a demonstration project for the conversion of woody biomass to value adding chemical building blocks.

In December 2015 the consortium applied for European funding under the Horizon 2020 program and in April 2016 the proposal was positively evaluated by Bio Based Industries Joint Undertaking (BBI JU), a public/private partnership between the European Union and the Bio Based Industry.

BIOFOREVER intends to demonstrate the feasibility of various new value chains from lignocellulosic feedstocks to chemical building blocks like butanol, ethanol, 2, 5 – furandicarboxylic acid (FDCA) on an industrial scale.

Matti Heikkilä, Chief Technical Officer, MetGen Oy:

“MetGen has always been enthusiastic about building new industrial value-chains through collaboration. We are certain that it is already possible to be competitive against petroleum-based chemicals and the food-based sugars utilizing existing technologies – more than that, we can make better products than is possible through conventional processes. To be successful in such a task requires connecting the capabilities and expertise of several companies and research organizations to create complementary and complete processes. BIOFOREVER brings together the most potential technologies in Europe and unifies professionals behind them to tackle an ambitious goal of enabling next generation bio-refining industry.”    

A number of pre-treatment and subsequent conversion technologies will be demonstrated, including delivering commercialisation routes for the most promising value chains.

Nadège Laborde, president of Novasep’s Industrial Biotech Business Unit:

BIOFOREVER is supporting the development of a sustainable economy and is part of the European 2020 Strategy. This industrial project must demonstrate we can reach economically viable production of bio-sourced products from a range of woody biomass. Novasep is thrilled to be part of this ambitious project, which is poised to succeed.”

The demonstration project starts in September 2016 and will run for 3 years. The overall budget is € 16.2 million with a € 9.9 million contribution from BBI JU. Woody biomass, including waste wood will be converted to lignin, (nano-) cellulose and (hemi-) cellulosic sugars, and further converted to lignin derivatives and chemicals like butanol, ethanol and FDCA on industrial scale, where feedstocks will be benchmarked with crop residues and energy crops.

Typically, such bio-refineries will be projected in logistic hubs such as the Port of Rotterdam and other European ports.

Tim Davies, Chief Technical Officer, Green Biologics Ltd.:

“Green Biologics relishes the opportunity to work towards the aims of BIOFOREVER, which, through combining a strong consortium of industrial biotechnology, chemical and manufacturing companies and the best available technologies, will drive toward the commercialisation of renewable technology and the development of a world leading bio-refining industry.”

This demonstration project will provide ample space for commercialisation of industrial scale bio-refineries serving new value chains.

BIOFOREVER consortium partners:

·      API Europe, Greece

·      Avantium Chemicals BV, Netherlands

·      Bioprocess Pilot Facility BV, Netherlands

·      Borregaard AS, Norway

·      Bio Refinery Development BV, Netherlands

·      DSM, Netherlands

·      Elkem Carbon AS, Norway


·      Green Biologics Ltd, UK

·      MetGen Oy, Finland

·      Nova Institute, Germany

·      Novasep Process SAS, France

·      Phytowelt, Green Technologies GmbH, Germany

·      Port of Rotterdam, Netherlands

·      SUEZ Groupe, France


For further information contact +31620016964 or visit our website or BBI JU’s website



A Bacterial Laccase for Enhancing Saccharification and Ethanol Fermentation of Steam-Pretreated Biomass

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Antonio D. Moreno 1,2, David Ibarra 3,*, Antoine Mialon 4 and Mercedes Ballesteros 2
IMDEA Energía, Biotechnological Processes for Energy Production Unit, Móstoles, Madrid 28935, Spain
CIEMAT, Renewable Energy Division, Biofuels Unit, Avda. Complutense 40, Madrid 28040, Spain
INIA-CIFOR, Forestry Products Department, Cellulose and Paper Laboratories, Ctra de La Coruña Km 7.5, Madrid 28040, Spain
MetGen Oy, Rakentajantie 26, Kaarina 20780, Finland
* Correspondence: Tel.: +34-91-347-3948
Academic Editor: Ronnie G. Willaert
Received: 8 April 2016 / Accepted: 26 April 2016 / Published: 4 May 2016

Abstract: Different biological approaches, highlighting the use of laccases, have been developed as environmentally friendly alternatives for improving the saccharification and fermentation stages of steam-pretreated lignocellulosic biomass. This work evaluates the use of a novel bacterial laccase (MetZyme) for enhancing the hydrolysability and fermentability of steam-exploded wheat straw. When the water insoluble solids (WIS) fraction was treated with laccase or alkali alone, a modest increase of about 5% in the sugar recovery yield (glucose and xylose) was observed in both treatments. Interestingly, the combination of alkali extraction and laccase treatment boosted enzymatic hydrolysis, increasing the glucose and xylose concentration in the hydrolysate by 21% and 30%, respectively. With regards to the fermentation stage, the whole pretreated slurry was subjected to laccase treatment, lowering the phenol content by up to 21%. This reduction allowed us to improve the fermentation performance of the thermotolerant yeast Kluyveromyces marxianus CECT 10875 during a simultaneous saccharification and fermentation (SSF) process. Hence, a shorter adaptation period and an increase in the cell viability—measured in terms of colony forming units (CFU/mL)—could be observed in laccase-treated slurries. These differences were even more evident when a presaccharification step was performed prior to SSF. Novel biocatalysts such as the bacterial laccase presented in this work could play a key role in the implementation of a cost-effective technology in future biorefineries.

Keywords: alkaline extraction; bacterial Metzyme laccase; lignocellulosic ethanol; simultaneous saccharification and fermentation; thermotolerant yeast

1. Introduction

The transition towards a post-petroleum society for mitigating global climate change is currently led by the development and implementation of biorefineries. Biorefineries will be competitive, innovative and sustainable local industries for the production of plant- and waste-derived fuels, materials and chemicals. Due to its low costs and wide distribution, lignocellulosic biomass is the most promising feedstock to be used in biorefineries, and lignocellulose-derived fuels, including ethanol, the most significant product.
Many different feedstocks, conversion methods, and process configurations have been studied for lignocellulosic ethanol production, with the biochemical route being the most promising option [1]. Lignocellulose is a complex matrix where a ‘skeleton’ polymer, cellulose, is coated by two ‘protective’ polymers, hemicellulose and lignin. Biochemical conversion of lignocellulosic biomass includes a pretreatment step to open up the structure and increase biomass digestibility. Subsequently, cellulose and hemicellulose polymers are subjected to an enzymatic saccharification process to obtain the fermentable sugars. The optimal performance of cellulolytic enzymes is therefore a crucial step that determines the overall process efficiency. Finally, the resulting sugars are converted into ethanol via microbial fermentation [1].
Pretreatment influences lignocellulose digestibility by an extensive modification of the structure. A large number of pretreatment technologies, mainly physical and/or chemical, have been developed and applied on a wide variety of feedstocks [2]. Among them, hydrothermal pretreatments, such as steam explosion, are considered the most effective methods and are commonly used for lignocellulose-to-ethanol conversion. The action mechanism of these pretreatment technologies lies in the solubilisation of hemicellulose fraction and the redistribution and/or modification of lignin, which increase outstandingly the hydrolysis of cellulose without the need of adding any catalyst [3]. These pretreatment technologies, however, still present several drawbacks that must be overcome. First, the residual lignin that is left in the pretreated materials represents an important limiting factor during the enzymatic hydrolysis of carbohydrates, promoting the non-specific adsorption of hydrolytic enzymes and, in turn, decreasing saccharification yields [4]. Second, these pretreatment methods generate some soluble compounds, derived from sugar degradation (furan derivatives and weak acids) and partial lignin solubilisation (aromatic acids, alcohols and aldehydes), which inhibit cellulolytic enzymes and fermentative microorganisms [5]. Performing a delignification step prior to the addition of hydrolytic enzymes may reduce the non-productive adsorption of these enzymes, enhancing the saccharification yields. In the same way, a detoxification process may reduce the amount of inhibitors produced after steam explosion pretreatment, boosting the saccharification and fermentation steps. Different physico/chemical technologies have been studied for delignification and detoxification of pretreated materials [2,6]. However, most of these methods require extra equipment and additional steps and have high energy demands, complicating the lignocellulose-to-ethanol process and increasing the production costs. As an alternative to physico/chemical methods, the use of ligninolytic enzymes such as laccases may provide further integration into the process and lower energy requirements [7].
Laccases are multicopper oxidases that catalyze the one-electron oxidation of phenols, anilines and aromatic thiols to their corresponding radicals with the concomitant reduction of molecular oxygen to water. Laccases are mainly produced by plants and fungi, including the white-rot basidiomycetes responsible for lignin degradation in nature [8]. Also, some bacterial laccases have been described and fully characterized, generally showing lower redox potential and more stable at high pH and temperatures compared to fungal laccases [9]. The role of laccases in lignin degradation makes them attractive biocatalysts for the pulp and paper industry as substitutes of chlorine-containing reagents in pulp bleaching [10,11]. Both fungal and bacterial laccases have been studied with beneficial results [12,13]. Moreover, they are used in wastewater treatment to detoxify industrial effluents with high phenolic content—such as the streams obtained during pulp and paper production—due to their ability to oxidize phenolic compounds [14,15].
The vast experience gained from the extensive use of laccases in the paper pulp industry has provided an excellent starting point for the application of laccases within a broader perspective. In this context, different fungal laccases have been widely studied for improving the conversion efficiency of lignocellulose into ethanol, and consequently increasing final product concentrations [7,16,17,18,19,20,21,22,23,24,25]. Nevertheless, little is known about the use of bacterial laccases for these purposes. The present work evaluates the commercial bacterial laccase MetZyme, exploring its potential for improving the hydrolysability and fermentability of steam-exploded wheat straw.

2. Materials and Methods

2.1. Raw Material and Steam Explosion Pretreatment

Wheat straw, supplied by CEDER-CIEMAT (Soria, Spain), was used as raw material. It presented the following composition (% dry weight (DW)): cellulose, 40.5 ± 2.1; hemicelluloses, 26.1 ± 1.1 (xylan, 22.7 ± 0.5; arabinan 2.1 ± 0.4; and galactan, 1.3 ± 0.2); Klason lignin, 18.1 ± 0.8; ashes, 5.1 ± 0.3; and extractives, 14.6 ± 0.4.
Prior to steam explosion, wheat straw was milled in a laboratory hammer mill to obtain a chip size between 2 and 10 mm. Then, the milled material was pretreated in a 10 L reactor at 200 °C for 2.5 min. The recovered slurry was handled differently depending on its further use. For analytical purposes, one portion was vacuum filtered with the aim of obtaining a liquid fraction or prehydrolysate and a solid fraction. Subsequently, the solid fraction was thoroughly washed with distilled water to obtain the water insoluble solids (WIS) fraction. Chemical composition of both raw and pretreated material (WIS fraction) was determined using the Laboratory Analytical Procedures (LAP) for biomass analysis, provided by the National Renewable Energies Laboratory [26]. Sugars and degradation compounds contained in the liquid fraction were also measured. Most of the sugars present in the liquid fraction were in oligomeric form, and therefore a mild acid hydrolysis (4% (v/v) H2SO4, 120 °C and 30 min) was required to determine the concentration of monomeric sugars. The obtained WIS fraction was also used for saccharification studies since the majority of the inhibitory compounds were removed. On the other hand, the remained slurry was used as substrate to evaluate its fermentability due to the higher inhibitor content. Both WIS and slurry were stored at 4 °C until their use.

2.2. Enzymes

An industrial thermostable bacterial laccase (pH range 3–8) was specifically selected from MetGen’s products portfolio (MetZyme, Cat.-No: 10-101-UF, MetGen Oy, Kaarina, Finland), and used in both saccharification and fermentation assays. Laccase activity (284 IU/g of laccase activity) was measured by oxidation of 5 mM 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) to its cation radical in 0.1 M sodium acetate (pH 5) at 24 °C. Formation of the ABTS cation radical was monitored at 436 nm (ε436 = 29,300 M−1·cm−1).
A mixture of NS50013 and NS50010, both produced by Novozymes (Bagsvaerd, Denmark), was used for the saccharification of steam-pretreated what straw. NS50013 (60 FPU/mL of cellulase activity) is a cellulase preparation that presents low β-glucosidase activity and therefore it requires the supplementation with NS50010 (810 IU/mL of β-glucosidase activity), which mainly presents β-glucosidase activity. Overall cellulase activity was determined using filter paper (Whatman No. 1 filter paper strips), while β-glucosidase activity was measured using cellobiose as a substrate. The enzymatic activities were followed by the release of reducing sugars [27].
One unit of enzyme activity was defined as the amount of enzyme that transforms 1 μmol of substrate per minute.

2.3. Microorganism and Growth Conditions

Kluyveromyces marxianus CECT 10875, a thermotolerant strain selected by Ballesteros et al. [28], was employed as fermentative microorganism in this study. Active cultures for inoculation were obtained in 100-mL flasks with 50 mL of growth medium containing 30 g/L glucose, 5 g/L yeast extract, 2 g/L NH4Cl, 1 g/L KH2PO4, and 0.3 g/L MgSO4·7H2O. After 16 h on an orbital shaker at 150 rpm and 42 °C, the precultures were centrifuged at 9000 rpm for 10 min. Supernatant was discarded and cells were washed once with distilled water and diluted accordingly to obtain an inoculum level of 1 g/L DW.

2.4. Laccase Treatment and Saccharification of the WIS Fraction

The WIS fraction obtained after steam explosion (200 °C, 2.5 min) was subjected to a sequential laccase treatment and saccharification directly (Strategy 1) or after a mild alkaline extraction (Strategy 2).
Strategy 1, sequential laccase treatment and saccharification: 2.5 g DW of the corresponding WIS fraction were suspended in 50 mM sodium citrate buffer (pH 5.5) in 100-mL shake flasks to reach a final concentration of 5% (w/v) total solids (TS). This solution was treated with MetZyme laccase (10 IU/g DW substrate) for 24 h at 50 °C and 150 rpm in an orbital shaker. After 24 h of laccase treatment, solids were filtered through a Büchner funnel, washed with 1 L of water and dried at 60 °C. In a subsequent step, the laccase-treated WIS fraction was resuspended with 50 mM sodium citrate buffer (pH 5.5) in 100-mL flasks to reach a final concentration of 5% TS (w/v). Solids were subjected to saccharification at 50 °C for 72 h in an orbital shaker (150 rpm), with an enzyme loading of 5 FPU/g DW substrate of NS50013 and 5 IU/g DW substrate of NS50010.
Strategy 2, mild alkaline extraction and sequential laccase treatment and saccharification: 2.5 g DW of the corresponding WIS fraction was extracted with alkali (2.5% NaOH, for 1 h at 60 °C and 5% TS (w/v) substrate loading) followed by filtration and water washing. Then, the alkali-extracted WIS fraction was resuspended in 50 mM sodium citrate buffer (pH 5.5) in 100-mL flasks to reach a final concentration of 5% TS (w/v) and subjected to sequential laccase treatment and saccharification as explained above.
The effects of bacterial laccase treatments on both WIS fractions were evaluated in terms of (1) chemical composition and (2) saccharification yields. The chemical composition of laccase-treated WIS, subjected or not to a mild alkaline extraction, was determined using the NREL-LAP for biomass analysis [26]. On the other hand, the enzymatic hydrolysates obtained from laccase-treated WIS (with and without a previous mild alkaline extraction step) were centrifuged to remove the remaining solids, and the supernatants were analyzed to determine glucose and xylose concentration. For a better comparison between assays, relative glucose/xylose recoveries (RGR; RXR) were calculated as following Equation (1):
RGR (%) = g/L glucoseassay × 100/g/L glucosecontrol 
For RXR (%), similar equation was used but with xylose concentration instead.
Control assays were performed under same conditions in Strategy 1 and Strategy 2 without the addition of MetZyme laccase. All the experiments were carried out in triplicate.

2.5. Laccase Treatment and Fermentation of the Whole Slurry

The whole slurry obtained after steam explosion (200 °C, 2.5 min) was subjected to laccase treatment and simultaneous saccharification and fermentation without (Strategy 3) and with (Strategy 4) a presaccharification step to evaluate its fermentability.
Strategy 3, consecutive laccase treatment and simultaneous saccharification and fermentation (LSSF): 2.5 g DW of the corresponding slurry was suspended with 50 mM sodium citrate buffer (pH 5.5) in 100-mL flasks to reach a final concentration of 10% TS (w/v). Then, 10 IU/g DW substrate of MetZyme laccase were added and the mixture was incubated at 50 °C and 150 rpm in an orbital shaker for 24 h. After laccase treatment, the slurries were subsequently subjected to a simultaneous saccharification and fermentation (SSF) process at 42 °C for 72 h in an orbital shaker (150 rpm). Laccase-treated slurries were subjected to SSF after the supplementation with 15 FPU/g DW substrate of NS50013, 15 IU/g DW substrate of NS50010, nutrients (those described for cell propagation, except glucose) and 1 g/L DW of K. marxianus.
Strategy 4, consecutive laccase treatment with presaccharification and simultaneous saccharification and fermentation (LPSSF): 2.5 g DW of the corresponding slurry were suspended in 50 mM sodium citrate buffer (pH 5.5) in 100-mL flasks to reach a final concentration of 10% TS (w/v). Then, 10 IU/g DW substrate of MetZyme laccase were added and the mixture was incubated at 50 °C and 150 rpm in an orbital shaker. After 16 h of laccase treatment, a presaccharification step was carried out for 8 h by supplementing the slurries with 15 FPU/g DW substrate of NS50013 and 15 IU/g DW substrate of NS50010. Afterwards, the temperature was reduced to 42 °C and nutrients and 1 g/L DW of K. marxianus were added, which turned the process into a SSF. The experiments were run for another 72 h.
The effect of MetZyme laccase on specific inhibitory compounds was evaluated before yeast addition, i.e., right after laccase treatment or laccase treatment with presaccharification. For that, prior starting SSF processes samples were taken and centrifuged, and the supernatants were analyzed for the identification and quantification of inhibitory compounds. In the same way, samples were periodically withdrawn during SSF processes to determine cell viability and glucose and ethanol concentration (a centrifugation step was included prior to analyze glucose and ethanol concentration).
Control assays were performed under the same conditions without the addition of MetZyme laccase. All the experiments were carried out in triplicate.

2.6. Analytical Methods

Ethanol was analyzed by gas chromatography, using a 7890A GC System (Agilent, Waldbronn, Germany) equipped with an Agilent 7683B series injector, a flame ionization detector and a Carbowax 20 M column operating at 85 °C. Injector and detector temperature was maintained at 175 °C.
Sugar concentration was quantified by high-performance liquid chromatography (HPLC) in a Waters chromatograph equipped with a refractive index detector (Waters, Mildford, MA, USA). A CarboSep CHO-682 carbohydrate analysis column (Transgenomic, San Jose, CA, USA) operating at 80 °C with ultrapure water as a mobile-phase (0.5 mL/min) was used for the separation.
Furfural and 5-hydroxymethylfurfural (5-HMF) were analyzed and quantified by HPLC (Agilent, Waldbronn, Germany), using a Coregel 87H3 column (Transgenomic, San Jose, CA, USA) at 65 °C equipped with a 1050 photodiode-array detector (Agilent, Waldbronn, Germany). As mobile phase, 89% 5 mM H2SO4 and 11% acetonitrile at a flow rate of 0.7 mL/min were used.
Formic acid and acetic acid were also quantified by HPLC (Waters, Mildford, MA, USA) using a 2414 refractive index detector (Waters, Mildford, MA, USA) and a Bio-Rad Aminex HPX-87H (Bio-Rad Labs, Hercules, CA, USA) column maintained at 65 °C with a mobile phase (5 mmol/L H2SO4) at 0.6 mL/min of flow rate.
Total phenolic content was analyzed according to the Folin-Ciocalteu procedure [29]. 0.5 mL of sample and the serial standard solution (gallic acid) were introduced into test tubes with 2.5 mL of Folin-Ciocalteu’s reagent (1:10 dilution in water) and 2 mL of sodium carbonate (7.5% w/v). The tubes were incubated for 5 min at 50 °C. After cooling down the temperature, the absorbance was measured at 760 nm using a Lambda 365 spectrophotometer (PerkinElmer, Boston, MA, USA).
Cell viability was measured by cell counting using agar plates (30 g/L glucose, 5 g/L yeast extract, 2 g/L NH4Cl, 1 g/L KH2PO4, and 0.3 g/L MgSO4·7H2O, 20 g/L agar). Plates were incubated at 42 °C for 24 h.
All analytical values were calculated from duplicates or triplicates. Statistical analyses were performed using IBM SPSS Statistics v22.0 for MacOs X Software (SPSS, Inc., Chicago, IL, USA). The mean and standard deviation were calculated for descriptive statistics. When appropriate, analysis of variance (ANOVA) with or without Bonferroni’s post-test was used for comparisons between assays. The level of significance was set at p < 0.05, p < 0.01 or p < 0.001.

3. Results and Discussion

3.1. Pretreated Biomass Composition

Steam explosion pretreatment was performed at 200 °C and 2.5 min (Table 1). In comparison to the cellulose content of the untreated wheat straw (40.5%), steam explosion increased the cellulose proportion of the WIS fraction (53.5%) due to an extensive hemicellulose solubilization and degradation. This solubilization is evidenced by the lower proportion of the remaining hemicellulose (11.7%) fraction of the WIS residue and the high xylose content (32 g/L) in the liquid fraction. Also, different degradation products were recovered in the liquid fraction due to biomass degradation. The most predominant inhibitors were acetic acid, formic acid, furfural, 5-HMF and phenols (Table 1). Acetic acid is formed by the hydrolysis of acetyl groups contained in the hemicellulose structure. Formic acid derives from furfural and 5-HMF degradation, which in turn, results from pentoses (mainly xylose) and hexoses degradation, respectively. Finally, phenols are released during lignin partial solubilization and degradation of lignin [5,30]. A wide variety of phenolic substituted compounds such as 4-hydroxybenzaldehyde, vanillin, syringaldehyde, p-coumaric acid or ferulic acid, have been identified in steam-exploded wheat straw [3,31].

Table 1. Composition of steam-exploded wheat straw at 200 °C, 2.5 min.

3.2. Laccase Treatment and Saccharification of the WIS Fraction

The WIS fraction obtained after pretreatment of wheat straw at 200 °C, 2.5 min was subjected to laccase treatment and saccharification with and without a mild alkaline extraction: Strategy 1, sequential laccase treatment and saccharification; and Strategy 2, mild alkaline extraction and sequential laccase treatment and saccharification.

3.2.1. Effect of Bacterial Laccase Treatment on the Chemical Composition of WIS

The chemical composition of laccase-treated WIS, without and with a previous mild alkaline extraction step, was determined and compared with their respective controls (Table 2). In the case of those pretreated materials that were not subjected to an alkaline extraction, no relevant changes in the lignin content were observed after treatment with MetZyme laccase. Contradictory results have been described with fungal laccases on steam-pretreated materials. Moilanen et al. [21] obtained no substantial variation in the lignin content after laccase (Cerrena unicolor) treatment of steam-pretreated giant reed (Arundo donax). Similar results were obtained by Martín-Sampedro et al. [20,32] when steam-exploded eucalypt was treated with Myceliophtora thermophila laccase. In contrast, Oliva-Taravilla et al. [33] observed a slight increment in the lignin content of unwashed steam-exploded wheat straw after treatment with Pycnoporus cinnabarinus laccase. Likewise, Moilanenet al. [21] also described a lignin content increment in steam-pretreated spruce (Picea abis) treated with C. unicolor laccase.

Table 2. Composition of WIS samples treated with bacterial MetZyme laccase without or with a prior alkaline extraction.
It is known that alkaline treatment of steam-exploded materials decreases lignin content considerably [23,34,35]. In our study, the alkaline treatment was performed at mild conditions and caused 9% delignification (the mean difference is not significant at the 0.05 level) of steam-exploded wheat straw. When MetZyme laccase treatment was subsequently applied to the alkali-extracted WIS, no benefit were found by combining both treatments and similar values of delignification (11%) were observed (Table 2).

3.2.2. Effect of Bacterial Laccase Treatment on Saccharification Yields

RGRs and RXRs obtained after the saccharification of the WIS fractions treated with laccase are shown in Figure 1. In the case of Strategy 1 (sequential laccase treatment and saccharification), RGR of laccase-treated assays was increased by almost 5% (the mean difference is not significant at the 0.05 level) compared to control hydrolysates (Figure 1A). Similarly, an increment on RXR (3%, the mean difference is not significant at the 0.05 level) was also observed (Figure 1B). Even though no major changes were observed in the lignin content after treatment with this bacterial laccase, the slightly better saccharification yields could be attributed to the modification of the lignin structure on the WIS surface, which would affect the interaction of hydrolytic enzymes with the pretreated material. In this context, the action mechanism of laccases towards phenolic lignin units is altering the hydrophobicity of lignin and, consequently, lowering the non-specific adsorption of cellulases to this polymer. Palonen and Viikari [24] reported an increment of carboxyl groups of lignin from steam-pretreated spruce after treatment with the fungal T. hirsuta laccase, decreasing the hydrophobicity of lignin and increasing surface charge. These changes reduced the non-specific adsorption of hydrolytic enzymes on lignin, enhancing saccharification yields. Similar results were also obtained by Moilanen et al. [21] when steam-pretreated spruce was treated with C. unicolor laccase. Nevertheless, these authors also reported an increase in the non-specific adsorption of cellulases and lower glucose recovery yields when laccase treatment was performed on steam-pretreated giant reed. Oliva-Taravilla et al.[33] also described lower saccharification yields when steam-exploded wheat straw was treated with the fungal P. cinnabarinus laccase. In that work, the increment in Klason lignin observed in laccase-treated WIS was related to a grafting phenomenon of soluble phenols onto the lignin polymer, which hinders the accessibility of cellulolytic enzymes to cellulose and therefore reduces sugar recoveries.

Figure 1. Relative glucose (RGR) (a) and xylose (RXR) (b) recoveries at 72 h of enzymatic hydrolysis of WIS samples resulting from the different MetZyme laccase treatment and saccharification strategies. Strategy 1, sequential laccase treatment and saccharification (C, control sample; L, laccase sample). Strategy 2, alkaline extraction and sequential laccase treatment and saccharification (ALK + C, control sample with alkaline extraction; ALK + L, laccase sample with alkaline extraction). Glucose concentration values after 72 h of saccharification of control samples were 13.1 and 13.9 g/L for strategies 1 and 2, respectively. Xylose concentration values after 72 h of saccharification of control samples were 2 and 2.2 g/L for strategies 1 and 2, respectively. Mean values and standard deviations were calculated from the triplicates to present the results. Analysis of variance (ANOVA) with Bonferroni’s post-test was performed to identify differences between C, L, Alk + C or Alk + L. The mean difference is significant at the (*) 0.05 or (**) 0.01 level.
In the case of Strategy 2 (mild alkaline extraction and sequential laccase treatment and saccharification), the enzymatic hydrolysis of control assays extracted with alkali produced higher RGR (6%, the mean difference is not significant at the 0.05 level) and RXR (7%, the mean difference is not significant at the 0.05 level) values than the control assays not subjected to mild alkaline treatment (Figure 1). This enhancement in saccharification yields after the extraction with alkali is very well known [23,34,35]. Alkali extraction generates new irregular pores as a result of the removal of lignin and the disruption of lignin-carbohydrate complexes, contributing to an increase in the accessibility and susceptibility of cellulose and hemicellulose polymers to the action of hydrolytic enzymes. These advantages can be boosted by a subsequent laccase treatment due to the possibility of obtaining higher delignification ranges, increase the porosity and the available surface area, and decrease the non-specific adsorption of hydrolytic enzymes [19,24,25]. Thus, when alkali-treated WIS were subsequently subjected to laccase treatment, a synergistic effect was observed in the saccharification process, enhancing sugar recovery yields by 21% (p < 0.05) and 30% (p < 0.01) in RGR and RXR, respectively (Figure 1). The increase in both porosity and surface area promoted by the mild alkali extraction enables an easier penetration of laccase into the fibers, allowing a better accessibility to the lignin polymer. Similar results were found by Yang et al. [25] when using Brassica campestris straw as raw material. These authors observed by scanning electron microscopy (SEM) some irregular holes on the surface of B. campestris straw after alkali treatment, being increased not only in number and density but also in width and depth when the laccase extracted from the fungus Ganoderma lucidum was subsequently used. The same effect was described by Li et al. [19] in corn straw after combining pretreatment with NaOH and crude ligninolytic enzyme produced by the fungus Trametes hirsuta. These results strongly highlight the benefits of combining a mild alkali treatment with a bacterial laccase treatment for improving the hydrolysability of steam-exploded wheat straw.

3.3. Laccase Treatment and Fermentation of the Whole Slurry

In addition to offering the possibility of increasing the sugar content during the enzymatic hydrolysis, laccase can work as a detoxification agent to improve the fermentability of pretreated lignocellulosic materials [7]. With the aim of evaluating the effect of bacterial laccase treatment on the fermentability of steam-pretreated wheat straw, the whole slurry was subjected to laccase treatment and simultaneous saccharification and fermentation without and with a presaccharification step: Strategy 3, consecutive laccase treatment and simultaneous saccharification and fermentation (LSSF); and Strategy 4, consecutive laccase treatment with presaccharification and simultaneous saccharification and fermentation (LPSSF).

3.3.1. Effect of Bacterial Laccase Treatment on Inhibitory Compounds

The concentration of inhibitory compounds after treatment with MetZyme laccase, without and with an enzymatic presaccharification step, was determined and compared with their respective controls assays (Table 3). Inhibitory compounds can alter the growth of fermenting microorganisms and also inhibit/deactivate cellulolytic enzymes, decreasing final yields and productivities [5,36,37,38]. Furfural and 5-HMF have a direct inhibition effect on either the glycolytic or fermentative enzymes of the yeast, reducing equally biomass formation and ethanol yields. Acetic acid and formic acid reduce biomass formation by modifying the intracelular pH and promoting an imbalance in the ATP/ADP ratio. Finally, phenols alter biological membranes, affecting the growth rates and also inhibiting and deactivating hydrolytic enzymes.

Table 3. Inhibitory compounds concentration (g/L) of slurry samples treated with bacterial MetZyme laccase without or with enzymatic presaccharification.
In general, laccases catalyze the oxidation of phenols, generating unstable phenoxy radicals. These newly formed radicals interact with each other and lead to polymerization into aromatic compounds with lower inhibitory capacity. Total depletion in phenolic content seems to be impossible due to the structural characteristics of phenols [39]. Laccases can easily convert certain compounds, such as syryngaldehyde or cinnamic acids, whilst other phenolic compounds are oxidized with lower rates (vanillin) or remain intact (hydroxybenzaldehyde) [31,39]. Several studies have reported an incomplete removal of phenolic compounds. Kalyani et al. [18] described a phenol reduction of 76% when the whole slurry from steam-exploded rice straw was treated with Coltricia perennis laccase. Moreno et al. [22] achieved higher phenol reductions (93%–94%) whenP. cinnabarinus and T. villosa laccases were used on steam-exploded wheat straw. The same range was observed by Jurado et al. [17] with steam-exploded wheat straw and Coriolopsis rigida laccase and by Jönsson et al. [16] with SO2 steam-pretreated willow and Trametes versicolor laccase. These mentioned studies have in common the use of fungal laccases, mainly from white-rot basidiomycetes. In our case, the bacterial MetZyme laccase decreased the total phenolic content by 20%–21% (p < 0.01), independently of whether a presaccharification step is included (Table 3). In comparison to fungal laccases, the lower efficiency in phenol removal by this particular bacterial laccase can be attributed to the lower redox potential of bacterial laccases in general. The redox potential of fungal laccases is estimated to be around +730 mV and +790 mV, while bacterial or plant laccases have a redox potential of about +450 mV. This higher redox potential of fungal laccases increases their capability to act towards a wider range of phenolic compounds. Nevertheless, the lower redox potential might not represent the only explanation for the reduction in the oxidation capacity of bacterial laccases, as other factors such as Kcat/KM ratio (as a measure of enzyme efficiency) may also play an important role [40].
In contrast to the phenols reduction, furan derivatives and weak acids were altered by bacterial laccase in none of the strategies assayed (Table 3). The absence of laccase action on these type of inhibitory compounds has been already reported in previous studies with fungal laccases [16,17,22,31]. This substrate-specific reaction of laccases towards phenols offers some advantages over chemical and physical detoxification methods such as mild reaction conditions, the generation of fewer inhibitory sub-products and lower energy [41].

3.3.2. Effect of Bacterial Laccase Treatment on Cell Viability and Ethanol Production

Control and detoxified slurries, resulting from MetZyme laccase treatments without (L) and with the enzymatic presaccharification (LP), were subjected to SSF for 72 h at 42 °C. K. marxianuns CECT 10875 was used as the fermenting microorganism due to its ability to tolerate relatively high temperatures. Thermotolerant yeasts are gaining great significance due to the possibility of better integration between both saccharification and fermentation stages. Optimal temperatures for enzymatic hydrolysis are about 50 °C. In this context, the use of thermotolerant yeasts capable of growing and fermenting around those temperatures is beneficial for the performance of hydrolytic enzymes [31]. During fermentation assays, cell viability, glucose consumption and ethanol production were monitored (Figure 2 and Figure 3).

Figure 2. Consecutive laccase treatment and simultaneous saccharification and fermentation (LSSF, Strategy 3). (a) Viable cells during simultaneous saccharification and fermentation (SSF) assay with K. marxianus of slurry samples resulting from Metzyme laccase treatment. Symbols used: control (■) and laccase (▲) samples. (b) Time course for ethanol (filled symbols and continuous lines) and glucose (open symbols and discontinuous lines) during simultaneous saccharification and fermentation (SSF) assay with K. marxianus of slurry samples resulting from Metzyme laccase treatment. Symbols used: control (■, □) and laccase (▲, △) samples. Mean values and standard deviations were calculated from the triplicates to present the results.
Figure 3. Consecutive laccase treatment with presaccharification and simultaneous saccharification and fermentation (LPSSF, Strategy 4). (a) Viable cells during simultaneous saccharification and fermentation (SSF) assay with K. marxianus of slurry samples resulting from Metzyme laccase treatment with presaccharification. Symbols used: control (■) and laccase (▲) samples. (b) Time course for ethanol (filled symbols and continuous lines) and glucose (open symbols and discontinuous lines) during simultaneous saccharification and fermentation (SSF) assay with K. marxianus of slurry samples resulting from Metzyme laccase treatment with presaccharification. Symbols used: control (■, □) and laccase (▲, △) samples. Mean values and standard deviations were calculated from the triplicates to present the results.


During SSF of wheat straw slurry, cell viability—in the form of CFU/mL—decreased within the first 12 h in control assays (Figure 2A). This effect is correlated with the adaptation of the yeast to the different components in the fermentation medium, and usually promotes a delay in glucose consumption and ethanol production (Figure 2B). This adaptation period depends on different factors, such as the presence of inhibitory compounds, the nature and concentration of inhibitors and the synergistic effects between them [5,36].

The adaptation phase is overcome by K. marxianus after converting certain inhibitory compounds, including furfural and 5-HMF, to their less toxic forms. After being adapted, the yeast showed a remarkable increase in cell viability between 12 and 24 h of SSF, until reaching the value of 80 CFU/mL that remained constant for the rest of the process (Figure 2A). The increase in cell viability made it possible to obtain the maximum glucose consumption (values were not estimated due to the continuous release of glucose) and ethanol production rates (0.59 g/L·h between 12 and 24 h), lowering the glucose concentration to values below 0.1 g/L and reaching the highest ethanol concentration (12.3 g/L) within 48 h (Figure 2B,Table 4).

Table 4. Summary of simultaneous saccharification and fermentation (SSF) assays withK. marxianus of slurry samples treated with bacterial MetZyme laccase without or with enzymatic presaccharification.
When laccase-treated slurries were subjected to SSF, the fermentation performance of K. marxianus was slightly improved due to the lower phenolic content. This improvement was more evident in cell viability, where no reduction in the number of CFU/mL was observed within the first 12 h and a significant increase to about 120 CFU/mL was obtained between 24 and 72 h of fermentation (Figure 2A). Similar values of maximum ethanol production rates and maximum ethanol concentrations were observed for both control and laccase-treated slurries (Figure 2B, Table 4). However, a shorter adaptation phase was observed in those slurries treated with Metzyme, which can aid in reducing the overall process time. Similar improvements on the fermentation performance of K. marxianus and other fermenting microorganisms have been also observed when using fungal laccases. Moreno et al. [22,31] reported higher cell viability, glucose consumption rates and ethanol productivity values when steam-exploded wheat straw was treated with P. cinnabarinus and T. villosa laccases. Jönsson et al. [16] reported higher glucose consumption rate, ethanol productivity and ethanol yield when the liquid fraction from acid steam-exploded willow was treated with T. versicolor laccase and fermented with Saccharomyces cerevisiae. In the same way, Jurado et al. [17] observed higher biomass concentration, sugar consumption and ethanol yield after treating steam-exploded wheat straw with C. rigida laccase and fermenting it with S. cerevisiae.


In comparison to assays without a presaccharification step, the enzymatic prehydrolysis (P) extended the adaptation period of yeast cells during the subsequent SSF process (Figure 3A,B). A remarkable drop in cell viability was measured in non-treated slurries within the first 12 h of SSF, followed by a long stationary phase where no cell growth was observed. After 48 h, a sudden increase in cell viability could be seen, reaching a value of about 95 CFU/mL (Figure 3A). Regarding glucose concentration, the prehydrolysis stage increased the glucose content before inoculation up to 20 g/L. After inoculation, the adaptation phase of K. marxianus allowed the continuous accumulation of this sugar during the first 48 h of SSF, reaching a maximum value of 23 g/L. Supported by the increase in cell viability, glucose started to be consumed after 48 h, and values below 0.1 g/L were observed at 72 h of SSF (Figure 3B). Maximum ethanol concentration (12 g/L) and yield (0.29 g/g) were similar to those obtained in SSF processes without presaccharification, but this value was reached with a delay of 24 h (Table 4). The extended lag phase of K. marxianus during PSSF processes in comparison to that observed during SSF can be justified by the presence of a higher concentration of inhibitory compounds after the presaccharification step, especially for acetic acid and phenols (Table 3). According to Thomsen et al. [44], acetic acid is produced by the hydrolysis of acetyl groups in hemicelluloses, which involves the synergistic action of both hemicellulase and acetyl esterase activities. In this sense, the cellulolytic NS50013 preparation used in this study—obtained from Trichoderma spp. strains—contains xylanase and acetyl esterase activities that can release the acetyl groups that remain in the fibers, increasing the acetic acid concentration [45]. Similarly, the increment in the phenol content can be explained by the release of p-coumaric acid and ferulic acid during the presaccharification step. Ferulic acid and p-coumaric acid are two typical lignin phenolic compounds present in wheat straw [3,31]. The hydrolysis of these cinnamic acids is attributed to the complementary action of xylanase and phenolic acid esterase activities [31]. The esterase activities, highlighting feruloyl esterase activity, are naturally produced by Aspergillus niger, which is the strain producing the β-glucosidase NS50010 preparation [46].
When laccase treatment was combined with the presaccharification step (LP), the adaptation phase was reduced from 48 h in control assays to 24 h in laccase-treated slurries. This reduction can be seen in Figure 3A, where an increase from about 15 CFU/mL to above 100 CFU/mL was observed within 24 and 48 h of SSF. In comparison to LSSF process without a presaccharification stage where the number of CFU/mL was kept constant after the adaptation phase, in LPSSF process a remarkable decrease in cell viability took place within 48 and 72 h, which is an indicator of the higher inhibitory content even after laccase treatment. In relation to glucose consumption and ethanol production, similar rates (0.43 g/L·h and 0.44 g/L·h in control and laccase-treated slurries, respectively) were observed after the adaptation phase either in control or laccase-treated assays, which resulted in a maximum ethanol concentration of about 12 g/L—similar to those values obtained in the SSF processes without a presaccharification step (Figure 3B, Table 4). It is important to notice that higher ethanol concentrations than those obtained in the present work are needed for the cost-effectiveness of a commercial lignocellulosic ethanol production. Working at higher substrate concentrations is therefore imperative and a presaccharification step is typically included in the process in order to avoid certain problems such as mixing. In this context, the use of laccases could play a crucial role to increase the fermentability of steam-pretreated lignocellulosic materials.

4. Conclusions

The present work shows the potential of the bacterial MetZyme laccase for improving both the hydrolysability and fermentability of steam-pretreated materials. The laccase treatment of the WIS fraction resulted in slightly higher glucose and xylose recoveries during a saccharification process. This improvement was increased synergistically by the action of a mild alkaline extraction performed prior to laccase treatment. MetZyme laccase also showed modest phenol removal when treating the whole pretreated slurries, reducing the inhibitory effects of steam-exploded wheat straw. The lower inhibitory content led to improve the fermentation performance of K. marxianus in SSF processes with or without a presaccharification step, shortening its adaptation period and the overall fermentation times. These results represent an interesting approach to improve the efficiency of the ethanol production process, which might contribute to making lignocellulosic ethanol production economically viable. Nevertheless, other parameters, including laccase dosages and production costs, need to be further studied and optimized for the cost-effectiveness of the process.


Authors wish to thank the Spanish MIMECO for funding this study via Project CTQ2013-47158-R. Antonio D. Moreno acknowledges a “Juan de la Cierva” contract (FJCI-2014-22385).

Author Contributions

Antonio D. Moreno, David Ibarra, Antoine Mialon, and Mercedes Ballesteros participated in the design of the study. Antonio D. Moreno and David Ibarra performed the experimental work and wrote the manuscript. Antonio D. Moreno, David Ibarra, Antoine Mialon, and Mercedes Ballesteros conceived the study and commented on the manuscript. All the authors read and approved the final manuscript.

Conflicts of Interest

Antoine Mialon is Application Team Leader at Metgen Oy.


The following abbreviations are used in this manuscript:

WIS Water Insoluble Solids fraction
NREL-LAP National Renewable Energies Laboratory-Laboratory Analytical Procedures
SSF Simultaneous Saccharification and Fermentation
CFU Colony Forming Units
DW Dry Weight
LAP Laboratory Analytical Procedures
IU International Units
FPU Filter Paper Units
TS Total Solids
RGR Relative Glucose Recovery
RXR Relative Xylose Recovery
LSSF consecutive Laccase treatment and Simultaneous Saccharification and Fermentation
LPSSF consecutive Laccase treatment with Presaccharification and Simultaneous Saccharification and Fermentation
5-HMF 5-hydroxymethylfurfural
C Control treatment
CP Control treatment with Presaccharification
L Laccase treatment
LP Laccase treatment with Presaccharification
Alk Alkaline extraction
ATP/ADP Adenosine-5′-triphosphate/Adenosine-5′-diphosphate


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Entsyymeillä miljoonasäästöt paperiteollisuuteen (Kauppalehti 9.6.2015)

By News
MetGenin pilottilaboratoriossa luodaan prosessit entsyymien teollista tuotantoa varten. Teknologiajohtaja Matti Heikkilän mukaan ensimmäiset teolliset sovellukset otetaan sellunvalmistuksessa käyttöön vuoden loppuun mennessä.

MetGenin pilottilaboratoriossa luodaan prosessit entsyymien teollista tuotantoa varten. Teknologiajohtaja Matti Heikkilän mukaan ensimmäiset teolliset sovellukset otetaan sellunvalmistuksessa käyttöön vuoden loppuun mennessä.

Kaarinalaisen MetGenin kehittämillä entsyymeillä voidaan saada jopa 10-25 prosentin energiansäästö sellunvalmistuksen termomekaanisessa jauhatuksessa. Paperitehtaalle se tietää miljoonasäästöjä.

Sellu on biotalouden yksi kulmakivi. MetGenin tuotteet ovat siten biotuoteliiketoiminnan ytimessä.

Yhtiö on saanut EU:n Horisontti 2020 -ohjelmasta tukea tuotekehitykseensä.

MetGen kehittää myös entsyymejä, joilla voidaan erottaa puusta biokemikaalien avulla tisleitä. Niistä taas valmistetaan erilaisia biotuotteita.

”Ensimmäiset teolliset sovellukset otetaan sellunvalmistuksessa käyttöön vuoden loppuun mennessä. Termomekaanisen jauhatuksen säästöt tarkoittavat miljoonasäästöjä paperitehtaalle vuositasolla”, MetGenin teknologiajohtaja Matti Heikkilä sanoo.

Toinen esimerkki entsyymien hyödyistä löytyy kuluttajatuotteista.

”Kaikki maailman muovipullot ja -pakkaukset voidaan ehkä valmistaa uusiutuvasta materiaalista – puusta. Se ei onnistu vain entsyymeillä, mutta ne ovat tärkeä osatekijä tuossa arvoketjussa”, Heikkilä sanoo.

Heikkilän mukaan biotalous ymmärretään Suomessa turhan kapea-alaisesti.

”Pitää hahmottaa kokonaisuuksia, joihin osaamisemme sopii ja keskittyä olennaisiin asioihin. Meillä on mahdollisuuksia luoda maailmanluokan arvoketjuja, jos panostamme oikeisiin kohteisiin”, hän sanoo.

Puusta tai muusta lignoselluloosapohjaisesta materiaalista voidaan Heikkilän mukaan tehdä entsyymien avulla vaikkapa pinta-aktiivisia aineita, aromeja, palonestoaineita, antioksidantteja, fenolihartsia, puu-muovikomposiitteja ja pinnoitteita. Niistä taas voidaan valmistaa lääkkeitä, kemikaaleja, lannoitteita, autonosia, muoveja, maaleja, liimoja ja tekstiilejä.

”Niissä kaikissa on entsyymeillä osansa, mikäli emme halua käyttää paljon energiaa tai liuottimia”, hän sanoo.

MetGenin ensimmäisinä kehittämät molekyylit olivat hajottajaentsyymejä, joita esiintyy myös luonnossa. Yhtiön entsyymit kestävät muista entsyymeistä poiketen jopa 85 asteen lämpötiloja ja korkeita ph-pitoisuuksia. Entsyymi käy puussa ligniinin kimppuun, joka sitoo arvokkaan selluloosan hemiselluloosaan. Siksi se tuo selluvalmistukseen energiasäästöjä ja nopeuttaa prosessia.

Entsyymeillä voidaan käsitellä märkää biomassaa poistamatta vettä. Se yksinkertaistaa prosesseja ja mahdollistaa käsittelyn ilman kovaa kuumuutta, painetta tai liuottimia.

Tähän asti entsyymien ongelmana on ollut herkkyys ulkopuolisille tekijöille, kuten liialle lämmölle tai prosessin kemikaalipitoisuudelle. Ne ovat olleet myös hintansa vuoksi kilpailukyvyttömiä, mutta eivät enää.

MetGen on vuonna 2008 perustettu yhtiö, jossa työskentelee 15 henkeä. Yhtiö on herättänyt kansainvälistä kiinnostusta heti alusta alkaen. Sitä ovat rahoittaneet sveitsiläinen Emerald Technology Venture -rahasto ja ranskalainen pääomasijoittaja Sofinova Partners.


Vuonna 2010 yhtiö voitti European Venture -sijoittajakisan. Muita tunnustuksia ovat valinta 2013 Global Cleantech top 100:aan ja viime vuoden Top 10 Global Cleatech Cluster Assosiationin (GCCA:n) palkinto Best in BioFuels/BioEnergy.

MetGen on päässyt mukaan myös EU:n Horisontti 2020 -ohjelmaan ja saanut 2,2 miljoona euroa maksavaan projektiinsa 70 prosentin rahoituksen Horisontti-ohjelmasta.

”EU:n pk-instrumentti on meille tärkeä lisä tuotannon skaalaamiseksi teolliseen mittakaavaan ja markkinointiin. Tällaiseen rahoitukseen pitäisi panostaa, jotta hyvät kansalliset ideat eivät jää käyttämättä tai päädy liian aikaisin ulkomaille”, Heikkilä sanoo.

”EU:n Horisontti 2020 -rahoitusohjelmassa on useita mahdollisuuksia rahoittaa yritysten kasvua ja innovaatioita. Esimerkiksi pk-instrumentilla tuetaan hankkeiden soveltuvuus- ja markkinatutkimuksista aina pilottilaitosten rakentamiseen”, sanoo EU-asiantuntija Pirjo PasanenSpinverse Oy:stä.

Suomalaiset yritykset ovat menestyneet erityisesti toisen vaiheen pk-instrumenttihauissa, joista yritys voi saada rahoitusta jopa 2,5 miljoonaa, mutta kilpailu rahasta on kovaa.

”Rahoitetun hankkeen takana on aina huippuidea ja selkeä näkemys tavoitteista, mutta myös hakemukseen ja projektin vaikuttavuuden kuvaamiseen on panostettava”, Pasanen sanoo.

Maailmalla tehdään paljon entsyymitutkimusta. Painopiste on lääketieteeseen, elintarvikkeisiin, tekstiileihin tai vaikkapa eläinten rehuihin liittyvässä entsyymitutkimuksessa.

MetGen on valinnut alueen, johon ei ole maailmalla tungosta. Megatrendit antavat vauhtia alalle, jossa huipputeknologia yhdistyy energian säästöön, uusiin materiaaleihin ja kestävään kehitykseen.

Yhtiön valtti on nopea tuoteräätälöinti. Se sanoo pystyvänsä alle vuodessa kehittämään molekyyli-ideasta teollisen tuotteen. Se on yhtiön kokoon nähden harvinaista jopa globaalisti.

Yhtiön Kaarinan yksikkö keskittyy pelkästään tuotteiden kehittämiseen ja asiakasprosesseihin. Yhtiö on ulkoistanut tuotevalmistuksen.

”Meillä on useita yhteistyökumppaneita Euroopassa. Maailmalla on paljon fermentointikapasiteettia eikä meidän kannata ainakaan toistaiseksi investoida siihen”, Heikkilä sanoo.

Lue artikkeli Kauppalehden sivuilta tästä.

Kaarinalaisen MetGenin entsyymit tuovat metsäteollisuudelle miljoonasäästöt

By News

Prosessin nopeuttaminen, energiansäästö ja ympäristörasituksen pienentäminen ovat jatkuvia haasteita muun muassa paperi- ja selluteollisuudelle. Kaarinalaisen MetGen Oy:n kehittämät entsyymit tarjoavat niihin vihreän ratkaisun, joka vakuutti myös EU:n Horisontti 2020 -rahoittajat.

Vuonna 2008 perustetun MetGenin bisnesidea on sinällään yksinkertainen: yhtiön tavoitteena on nopeuttaa asiakkaan tuotantoprosessia, kutistaa energialaskua ja pienentää tuotannon ympäristökuormaa. Hienon ohjauselektroniikan ja järjestelmien sijaan temppu tehdään kemiallisesti entsyymeillä, joita MetGen kehittää räätälintyönä mm. paperi- ja selluteollisuuden.

Idean ytimessä ovat luonnossakin esiintyvät hajottajaentsyymit, joita muunnellaan eri prosesseihin sopiviksi. Parhaimmillaan ne saadaan kestämään jopa 90 asteen lämpötiloja ja tekemään hajotustyötään moninkertaisesti normaalia nopeammin.

Paperitehtaille tämä tarkoittaa vuositasolla todella huomattavaa energiansäästöä.

– Räätälöityjä entsyymejä voidaan hyödyntää myös jätepohjaisten biopolttoaineiden valmistuksessa sekä jätevesien puhdistuksessa. Tulevaisuudennäkymät ovat tältä pohjalta vähintäänkin lupaavat, sanoo toimitusjohtaja Alex Michine.

Tutkimuslähtöinen yhtiö on tuomassa ensimmäisiä tuotteitaan markkinoille, joten liikevaihto on vielä pieni. Läpimurto on Michinen mukaan kuitenkin jo käsillä.

– Toteutuessaan se tarkoittaa todella nopeaa ja aggressiivista kasvua. Tavoitteemme on nousta lignoselluloosapitoisten biomassojen entsyymikäsittelyn globaaliksi ykköseksi, toimitusjohtaja visioi.

Entsyymibisneksen potentiaali on noteerattu myös rahoittajaportaassa, joita MetGen on kiinnostanut alusta lähtien.

Tekesin startup-lainan ja NIYn lisäksi MetGen on saanut matkan varrella rahoitusta muun maussa Averasta, Finnverasta ja Suomen Teollisuussijoituksesta. Tärkeitä ovenavaajia ovat olleet myös vuonna 2010 voitettu European Venture -sijoittajakisa, ranskalainen Sofinnova Partners sekä sveitsiläinen Emerald Technology Venture -rahasto.

Hiljattain yhtiö sai positiivisen rahoituspäätöksen Horisontti 2020 -ohjelman pk-instrumentista.

– Pk-instrumentti tarjoaa ainutlaatuisen mahdollisuuden saada rahoitusta ja löytää juuri meille sopivia yhteistyökumppaneita ilman isoa konsortiota, Michine toteaa.

Kehuja saa myös jo vuosia jatkunut kumppanuus Tekesin kanssa.

– Tekesin tuki ja asiantuntemus on ollut todella tärkeää, kun olemme vieneet tuotettamme laboratoriosta teollisen tuotannon tasolle. Samalla olemme myös päässeet yli monen yrityksen kohtaloksi koituvasta kuoleman laaksosta, Michine lisää.

Lähde: Aamuset