Enhanced phytase production from Nocardia sp. MB 36 using agro-residues as substrates: Potential application for animal feed production

摘要

Phytases have gathered considerable attention in recent years due to their applications in human and animal nutrition, environmental protection and biotechnology. Phytases were isolated and characterized from a variety of bacteria and fungi but rarelyfrom actinomycetes. In the present study, a Nocardia sp. MB 36, isolated from rice mill waste, was found to be a producer of a thermostable and acid/alkalistable phytase. Optimization of phytase production by Plackett-Bur-man designed experiments indicated that wheat bran, medium pH, FeS04 and CaCl2 are the most effective fermentation variables that influence the phytase yield under submerged fermentation. Further optimization of these four variables by using Closed-Composite-Design of response surfacemethodology resulted in enhancement of phytase production by 64.14%. This newly isolated phytase from Nocardia sp. has potentially desirable features for animal feed applications.