Cellulase and amylase production by Aspergillus niger Sl.1 in ammonia treated agrowastes and evaluation of some kinetic parameters of the enzymes

Abstract

production of celulase and amylase by Aspergillus niger Sl.1 in carboxy methyl cellulose (CMC) and in four ammonia – treated agrowastes, maize cob (MC), rice bran (RB), sorghum bran (SB) and wheat bran (WB) were investigated. Some kinetic parameters of the enzymes were also investigated. Among the agrowastes, maize cob recorded the highest cellulase activity (6.02 unitsmg-1ml-1) while wheat bran recorded the lowest cellulase activity (5.02 unitsmg-1ml-1). The highest amylase activity (4.64 unitsmg-1ml-1 was recorded in wheat bran medium. Optimum pH for cellulase and amylase activities range from 5.5 – 6.0 and 6.0 – 7.0 respectively in all the media studied. Optimum temperature for cellulase and amylase activities conducted on the crude enzyme extract indicated that cellulase in carboxymethylcellulose medium was the least stable both at room and refrigerated temperatures. The least stable amylase enzyme was recorded in rice bran and wheat bran media at room and refrigerated temperatures respectively after 21 days.
The implications of these results on the industrial production cellulase and amylase using the agrowastes are discussed.