Improvement of Cell Wall Degrading Enzymes Production by Alginate Encapsulated Trichoderma spp.

Abstract

Conidia of three Trichoderma isolates were formulated to make alginate pellets with or without 0.5 % chitin or dried fungal mycelium of Fusarium oxysporum as carbon source. The formulations were compared for their ability of in vitro chitinase and β-1,3-glucanase production with free fungal spore suspensions. Conidia entrapped in alginate with or without adjuvant showed high production of enzymes (especially for chitinase) even when repeated 4 times. The addition of chitin or dried fungal mycelium as adjuvant enhanced the enzyme production up to 5 and 2-fold for chitinase and β-1,3-glucanase, respectively. Alginate concentration and surface area of the beads affected the enzyme production. The optimum initial pH, incubation time and temperature were pH=6, 12 days and 40 °C for chitinase, and pH=7, 10 days and 35 °C for β-1,3-glucanase production. The improvement of cell wall degrading enzyme production by alginate encapsulated Trichoderma could explain the in vivo inhibitory effect of such formulations on the target phytopathogenic fungi.