Selection of High β-Glucanase Produced Aspergillus Strain and Factors Affecting the Enzyme Production in Solid State Fermentation

Abstract

Among five β-glucanase producing strains, Aspergillus terreus ASKU 10 was selected as the potential strain for the enzyme production in solid state fermentation using rice straw as substrate. Six factors, addition of rice bran, spore inoculums, cultivation time, initial moisture content, corn steep
liquor (CSL) and KH₂PO₄ contents were optimized using “one-factor-at-a-time” method for β-glucanase production. The highest β-glucanase activity achieved under the condition as following: 10 g rice straw without addition of rice bran, with 10⁷ spore inoculums, 5 days of cultivation time, 75% initial moisture content, 3.3 ml CSL and 0.825 g KH₂PO₄. Under this optimal condition β-glucanase production with 4,054 U/g dry substrate was obtained.