Screening of Some Fungi Associated with Maize Cob Degradation for Cellulase Activity

Fungi involved in the biodegradation of maizecob were isolated and screened for cellulase activity using glucose and carboxylmethyl cellulose as carbon sources. The effect of the carbon sources on cellulase production was determined. Eleven fungi species were isolated which include Rhizopus oryzae, Aspergillus flavus, Mucor racemosus, Aspergillus niger, Penicillium atrovenetum, Penicillium expansum, Botryotrichum piluliferum, Penicillium chrysogenum and Penicillium restictum. Effect of carbon source on cellulase production was also reported. The highest reducing sugar production for all fungi isolate was obtained on day 14 when carboxymethyl cellulose (CMC) was used as the carbon source; while the highest reducing sugar production was obtained on day 7 when glucose was used as the carbon source. Aspergillus niger had the highest production of reducing sugar (1.68mg/ml and 0.82/m) in CMC and glucose respectively while the lowest production was recorded for Mucor racemosus (0.69mg/,ml and 0.01mg/ml). All Aspergillus species and Penicilluim species isolated had very high reducing sugar production in CMC: Aspergillus flavus 1.24 mg/ml; A oryzae 1.08mg/ml, P expansum 1.60 mg/ml, P atrovenetum 1.43mg/ml except Penicillium chrysonenum and Penicillium restrictum with 0.78mg/ml and 0.81 mg/ml, respectively. Aspergillus and Penicillum species are good cellulase producers especially those that are associated with degrading maize cob. These organisms are considered suitable to increase the nutrient of maizecob, an agro industrial waste and consequently make them useful for animal feed production.