Benefits from additives and xylanase during enzymatic hydrolysis of bamboo shoot and mature bamboo

Effects of additives (BSA, PEG 6000, and Tween 80) on enzymatic hydrolysis of bamboo shoot and mature bamboo fractions (bamboo green, bamboo timber, bamboo yellow, bamboo node, and bamboo branches) by cellulases and/or xylanase were evaluated. The addition of additives was comparable to the increase of cellulase loadings in the conversion of cellulose and xylan in bamboo fractions. Supplementation of xylanase (1 mg/g DM) with cellulases (10 FPU/g DM) in the hydrolysis of bamboo fractions was more efficient than addition of additives in the production of glucose and xylose. Moreover, addition of additives could further increase the glucose release from different bamboo fractions by cellulases and xylanase. Bamboo green exhibited the lowest hydrolyzability. Almost all of the polysaccharides in pretreated bamboo shoot fractions were hydrolyzed by cellulases with the addition of additives or xylanase. Additives and xylanase showed great potential for reducing cellulase requirement in the hydrolysis of bamboo.

Evaluation of aqueous ammonia pretreatment for enzymatic hydrolysis of different fractions of bamboo shoot and mature bamboo

The production of fermentable sugars from different fractions of bamboo shoots and mature bamboos (Phyllostachys heterocycla var. pubescens) by cellulase and/or xylanase was investigated. Aqueous ammonia pretreatment exhibited high but different delignification capacities for different bamboo fractions. Supplementation of cellulases with xylanase synergistically improved the glucose and xylose yields of mature bamboo fractions. High hydrolyzability was observed in the hydrolysis of both non-pretreated and pretreated bamboo shoot fractions, suggesting pretreatment was not necessary for the hydrolysis of bamboo shoots. High hydrolyzability together with the advantages of low lignin content, fast growth, and widely distribution demonstrated that bamboo shoots were excellent lignocellulosic materials for the production of bioethanol and other biochemicals.