Trakya University Journal of Natural Sciences (Mar 2016)
PRELIMINARY CHARACTERIZATION OF CRUDE INULINASE ACTIVITY OF ASPERGILLUS WENTII
Abstract
This study aims to perform a partial characterization of the crude enzymatic extracts of Aspergillus wentii inulinase produced by using the Jerusalem artichoke as the only carbon source in a production medium, which is a new source for obtaining inulinase. The screening medium that contained inulin as the only carbon source used by Derycke and Wandamme (1984) was redesigned to include Jerusalem artichoke powder instead of inulin and was used for the inulinase production of A. wentii. The crude inulinase produced by A.wentii was preliminarily characterized for its activity and stability. Optimum pH, temperature and incubation times for the crude enzymatic extract were determined as pH 6.0, 35°C and 10 min, respectively. The Km and the Vmax values were calculated as approximately 1×10-4 M, and 6.134 mmol/ml/min for A. wentii inulinase, respectively. The enzyme activity was observed to be stable at the intervals of pH 3.0-6.0 (96.8%), to maintain its activity until 50°C, and to have 62.3% relative activity at 80°C. The results confirm that A. wentii inulinase can be an enzyme with industrial treatments due to its relationship with its substrate and its good pH stability and thermal stability. A. wentii inulinase can be a new and usable source for preparation of pure fructose from inulin-containing agricultural products.
