OPTIMIZATION OF PROCESS PARAMETERS FOR THE PRODUCTION OF L-GLUTAMINASE WITH MIXED SUBSTRATE BY SOLID STATE FERMENTATION USING ASPERGILLUS WENTII MTCC 1901

Vurity Sameera, K. Jaya Raju

Abstract: L-Glutaminase, an amidohydrolase enzyme has been a choice of interest in the treatment of leukaemia since the discovery of its anti-tumour properties. Because it is a potent anti leukemic agent and a flavor-enhancing agent used in the food industry, many researchers have focused their attention on L-glutaminase. L-Glutaminase is majorly produced by micro organisms including bacteria, yeast and fungi. In the present study, production of L-Glutaminase from fungi, Aspergillus wentii was reported. Solid state fermentation was followed in the study for the enzyme production using different agro-industrial by products which include coconut oil cake, sesame oil cake, groundnut oil cake and neem oil cake. Out of them potential substrates were screened and used as mixed substrate. Mixed substrate was selected by mixing coconut oil cake and sesame oil cake in different compositions. The best composition, 1.25gm coconut oil cake and 3.75gm sesame oil cake was selected. Effect of process parameters namely temperature, pH, incubation time, moisture content, inoculum volume on enzyme production was investigated. Also effect of supplementary carbon sources, nitrogen sources, metal ions and glutamine concentration was studied and their optimum conditions were determined. The organism produced high levels of enzyme at an optimum temperature of 28?C and optimum pH 7.0, after 120h of incubation with 40% inoculum volume and 50% moisture content. Enhanced production was obtained on addition of 1% W/V D-glucose, peptone, magnesium sulphate and 1% W/W glutamine as supplements which showed an increase to four folds. Using this optimized media components and parameters; the L-Glutaminase activity 496U/gds was obtained.

Keywords: L-Glutaminase, leukaemia, Aspergillus wentii, solid state fermentation, mixed substrate

DOI: https://doi.org/10.15623/ijret.2015.0405063