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CelluX™: Dry yeast solution for converting C6 and C5 sugars into cellulosic ethanol

Lesaffre, a pioneer in cellulosic ethanol

At Lesaffre, our research programs on fermentation of lignocellulosic hydrolysates started in 2008 with the goal of developing a commercial fermentation solution allowing producers to implement the business model that made their success in conventional bioethanol. Our innovation programs led to the development of CelluX™ our glucose and xylose co fermenting yeast strain CelluX™ makes it possible to advance it further from first generation ethanol allowing enhanced flexibility on the use of conventional, and alternative biomass. Suitable biomasses include cereal straw, wood, forestry residues, bagasse, and dedicated crops.

the first commercial plant producing cellulosic ethanol
was commissioned in 2013 with CelluX ™

The CelluX™ story

In 2012, Lesaffre acquired the XI technology – Xylose Isomerase technology – from Butalco integrate it into a Lesaffre industrial ethanol strain. This technology allows to convert the xylose into xylulose, naturally consumed by yeast, and not cofactor dependent.

The same year, Leaf was the first yeast producer to provide a yeast product able to convert C6 and C5 sugars from lignocellulosic hydrolysates into ethanol on a large scale. CelluX™ is a Saccharomyces cerevisiae yeast genetically engineered to consume xylose through the XI + XDH metabolic pathway.

In 2013, Lesaffre conducted work to improve the tolerance of the strain to second generation substrate’s specific inhibitors and obtained CelluX™ 2.

One year after, CelluX™ 3 was able to accelerate the consumption of xylose.

The 4th generation, CelluX™ 4, marketed since 2015 displays a further improved fermentation speed and shows enhanced xylose conversion.


Our research continues and we are continuously improving our strains to meet the evolving needs of the 2G ethanol producers.

CelluX™4 key benefits for the cellulosic ethanol industry

A high ability to resist inhibitors and stresses

CelluX™ 4 showcases excellent tolerance to second generation substrate’s specific inhibitors. This product is able to ferment despite high acetic acid and phenolic compounds concentrations. It had fast detoxification kinetics for HMF and furfural that are prevalent in hydrolysates receiving steam explosion pretreatment.

CelluX™4 is robust at different pH areas and has a high ethanol tolerance.

Commercially available in 2G ethanol key market

Since 2012, Leaf had track record on full-scale industrial production of CelluX™ under dry form and supply in the different regions of the world. It also includes the market access in the main countries working on lignocellulosic ethanol production.

We support you in your regulatory needs to import and use the product in compliance.

product format

CelluX™ is sold in 10kg boxes of dry yeast, which limits the volume to be transported and allows a storage at room temperature (<27°C) of 2 years, without major impact on its effectiveness.

About CelluX™ 4

Available in 10kg box

Dry format: 24 months from production date under recommended storage conditions

Initial yeast density in fermentation vessel of 10 – 20 million viable cells per milliliter (36-72 billion viable cells per galon)