Hydrolysis OF BIOMASS - HEMICELLULASES - Novozymes

A NOVOZYMES PRESENTATION:HYDROLYSIS OF BIOMASS -HEMICELLULASESPRESENTATION BY: JIM LIU, STAFF SCIENTISTSPEAKER: MICHAEL HERSHKOWITZ, SR RESEARCH ASSOCIATE

Hemicellulose are complex substrates

Hemicellulose to pentoseNR(1 4)-ß-D-Xylan endohydrolase (1 4)-ß-D-Xylan endohydrolase-L-Arabinofuranosidaseß-D-Xylosidaseß-D-XylosidaseNRRedNRRedL-ArabinoseD-Xylose-L-Arabinofuranosidase-L-Arabinofuranosidase

HemicellulasesXylanasesOther hemicellulases

Xylanase families have differentcharacteristics in hydrolysisGH11XylanaseGH10XylanasePrefers to cut mainchain away frombranchAble to cut main chainclose to xylose unitwith branch

Hydrolysis yield (glucose and xylose)Alkaline pretreatment can remove xylan sidechains which makes GH11 work better120%Corn cob hydrolysis (72 hr, pH5, 50 °C)100%GH10 xylanaseGH11 xylanase80%60%40%20%0%

Biomass in nature – the complex system• Cellulose is composed of along chains of the sugarglucose. Cellulosepolymers form fibrilswhich contain bothcrystalline and amorphousregions• The cell walls of woodyplants and grasses arecomposed mostly ofcellulose, lignin, andhemicellulose• Cellulose fibrils areembedded in a network ofhemicellulose and ligninSchematic representation of the lignifiedplant cell wallImage source: Boudet et al. 2003. Trends Plant Sci. 12: 576.

Cellulose to glucoseAddition of xylanase can improve cellulosicconversion100%Acid pretreated corn cobs, 15% TS, 4 d90%80%70%60%No xylanasePlus xylanase50%40%0 2 4 6 8 10 12 14Enzyme dose (mg/g cellulose)

Summary• Understanding hemicellulose substrate is critial(source, pretreatment impact)• Variety of hemicellulases have been discoveredfor many hemicellulose substrates (naturaldiversity, protein engineering)• Using hemicellulase together with cellulase tomaximize synergies in biomass hydrolysis

Thank youFor more information please visit us at:www.bioenergy.novozymes.comNOVOZYMES PRESENTATION 6/22/2011 10