Improvement of the biodegradation of some cellulosic wastes by acid pretreatment.

Acid pretreatment of cellulosic wastes improved their susceptibility to Fusarium acuminatum enzymes. The effectiveness of acid pretreatment was demonstrated with an increase in both fungal growth and enzyme activities. A growth yield of 0.15 g/100 ml was achieved on medium containing 5% acid pretreated pods of bean for 60 minutes. Avicelase (C1), carboxymethylcellulase (Cx) and B-glucosidase (C2) reached their maximal biosynthesis on acid pretreated wheat bran, sugar-cane bagasse and sawdust-containing media, respectively. Xylanase and pectinase attained their highest accumulation on pretreated pods of bean media. A mixture of free sugars has been released by acid pretreatment. O.199 g dry mycelium was obtained when the fungus was grown on 100 ml of medium containing hydrolysate of 10% H2SO4 pretreated pods of bean for 30 min. No cellulase enzymes could be detected on hydrolysate medium at the time that low contents of both xylanase and pectinase were accumulated.