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

Abstract

Fungi involved in the biodegradation of maize-cob 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 maize-cob, an agro industrial waste and consequently make them useful for animal feed production.

Analytical study on Fungal Cellulase Produced by Penicillium Expansum grown on Malus Domestica (Apple Fruits)

“…The lowest cellulase activity obtained on day 1 may be traceable to the organism just entering the lag phase hence the multiplication rate was slow, resulting in low enzyme production. This finding was contrary to the report of Bamigboye (2013), who recorded highest cellulase activity by fungi associated with maize cob degradation on day 3. This disparity might be due to difference in substrate used, the fermenting fungus and also difference in length of the incubation periods.…”

“…However, sometime optimum temperature does not coincide with optimum enzyme activity. The result was similar to what was reported by Bamigboye (2013) who indicated that the optimum temperature for cellulase production was 30 0 C Also, Penicillium expansum was found to grow most efficiently within all the temperature range tested.…”

Millet Cobs: A Source of Microbial Enzymes

“…The presence moulds such as A. fumigatus, A. flavus and R. stolonifer, in the undegraded sample could be a result of them being millet cobs microflora which agrees with the finding of Badau when A. nidulans, A. niger, R. arrhizus were isolated from unmalted millet grains. Bamigboye also isolated A. flavus, A. niger, Rhizopus oryzae from corn cobs [31,32]. Slightly acidic environment of the millet cobs may be responsible for their adaptation [33,34].…”

Effect of Blanching and Sun-Drying on the Nutritional and Microbiological Qualities of Vegetables in Ilorin Metropolis, Nigeria

“…Similar organisms were also isolated [22]; these microorganisms are common spoilage organisms of vegetables. Some of these microorganisms are normal flora of vegetables [24]. Many microorganisms that have been isolated from the vegetables must have found their ways through different means ranging from soil contact, exposure to air flora, use of organic manure and so on [25].…”