Chitinase Production by Trichoderma harzianum Grown on a Chitin-Rich Mushroom Byproduct Formulated Medium

PurposeThe aim of this work was to evaluate the use of chitin-rich mushroom (Agaricus bisporus) by-products chitin/glucan enriched fraction (M-Ch/G-F) as main carbon source for the production of chitinases by three different microorganisms (Trichoderma harzianum, Trichoderma atroviride and Bacillus licheniformis), in an attempt to obtain these enzymes using a cheap and abundant fermentation medium.MethodsMicroorganisms were grown in submerged fermentation using different media formulated with chitin powder (Ch(p)), colloidal chitin (Ch(c)) and M-Ch/G-F as the main carbon source, respectively. Enzyme productivity and secretion (secretome) was studied by electrophoretic and proteomic methods.ResultsAll microorganisms produced higher chitinase activity in a medium formulated with M-Ch/G-F as a carbon source compared to medium formulated with Ch(p) or CHc. T. harzianum showed the highest chitinase productivity (261.5mUL(-1) per day). Chitinase production was monitored by electrophoretic and proteomic methods. Electrophoretic method allowed the detection of 28 different proteins-three different chitinases with 82, 50 and 31kDa. Proteomic analysis could identify 161 different proteins: 60 of them hydrolases, and 80% having glycolytic activity-5 of them were chitinases. These results show that cultivation of T. harzianum in a cheap and abundant fermentation medium represents a good procedure for large scale production of chitinases.ConclusionsOur results show that cultivation of T. harzianum in a culture medium formulated with M-Ch/G-F, a cheap and abundant fermentation medium, is a good procedure for large scale production of glycosidases, particularly chitinases within a relatively short cultivation period of 6 days.