Screening of Wild-Type Fungal Isolates for Cellulolytic Activity

Background: In this study, wild-type fungal isolates, producing highly effective cellulolytic enzymes were selected for bioconversion of residues and waste from agriculture and rational utilization of energy resources for food production. Methods: We screened wild-type fungal isolates of Aspergillus, Penicillium, and Trichoderma with an enhanced ability to produce extracellular cellulase. We carried out solid-state fermentation on a medium of agricultural waste products, including wheat bran, beet peels, and cotton oil cake, as well as additional sources of nitrogen and mineral elements. Enzyme production by the fungal isolates was detected within 14 days of cultivation. Results: Of 17 strains of Trichoderma, Aspergillus, and Penicillium tested, we identified Penicillium strain K-2-25 and Trichoderma lignorium strain T-22 to have high cellulolytic activity. K-2-25 demonstrated the highest activity after 48 hours of cultivation. T-22 also showed significant cellulolytic activity. Penicillium strain K-2-25 showed cellulolytic activity for 98–270 hours during cultivation, and the amount of reduced glucose was 945 mg. T. lignorium T-22 was the second most active strain, with glucose reduction of 835 mg. Conclusion: The strains K-2-25 and T-22 will are be recommended for biotechnological applications, especially for bioconversion of poor hardly decomposable vegetable waste products, such as like straw, into useful biomass.