Production of inulinase from Rhizopusoryzae by solid state fermentation

Abstract

Fifty Rhizopus spp. isolates were obtained from local natural habitat. The ability of inulinase production by these isolates was screened. The isolate RC-2 which isolated from composite plants was the highest inulinase producer on modified Czapek-Dox agar in primary screening. Secondary screening revealed that the same isolate was the highest production on Nakamura broth medium. Isolate was identified as Rhizopusoryzae. Measurements of reducing sugars in crude filtrate which represent the products of enzyme revealed that Rhizopusoryzae RC-2 produced inulinaseextracellular. The optimum culture conditions for inulinase production by solid state fermentation included a mixture of Jerusalem artichoke Helianthus tuberosus tuber with sugarcane Saccharum sp. bagasse with a ratio (1:1) as carbon source, 2.5% of corn steep liquor as nitrogen source, moisturizing ratio (3:1) (v:w) with tap water, the best inoculums rate was 2.5×105 spore/ml and incubation at (30)ºC for 4 days.