Influence of the carbon and nitrogen sources on inulinase production by Aspergillus kawachii in submerged cultures

CHESINI, MARIANA; CAVELLO, IVANA; ROJAS, LORENA; CAVALITTO, SEBASTIÁN

Mar del Plata

Encuentro; VIII Encuentro Latinoamericano y del Caribe de Biotecnología. REDBIO Argentina 2013; 2013

RedBio

Inulinase is an industrial enzyme which has caught the attention of researchers. Inulinases are used for production of high fructose syrups, fructooligosaccharides and ethanol used in pharmaceutical and food industry. Inulin -a carbohydrate reserve composed of D-fructose- is widely prevalent in many plants, particularly in roots, and tubers such as dahlia, chicory and yacon. The production of inulinase has been reported from several fungal, yeast and bacterial strains. The aim of this work is to investigate the optimum conditions for the maximum production of inulinase by A. kawachii. In a previous work we reported that yacon extract was the best carbon source for the production of A. kawachii inulinase. Here, the effect of glucose, fructose, sucrose, pure inulin, sugarcane molasses and soybean molasses in combination with yacon extract at a concentration of 5g/l were investigated. It was possible to increase 2 fold enzyme activity when yacon was used in combination with soybean molasses. Glucose, fructose and sucrose inhibit inulinase production. The influence of various nitrogen sources (yeast extract, urea, ammonium nitrate and sodium nitrate) on the inulinase production was studied. Yeast extract was found to be most suitable one increasing 1.75 fold enzyme activity whereas ammonium ion was inhibitory.