Optimization of Solid State Fermentation Conditions for Biosynthesis of L-Asparaginase Enzyme using Wautersiaeutropha NRRL B-2804

This article reports on developing media by optimizing parameters for biosynthesis and isolation of bio-molecule L-Asparaginase from Wautersia eutropha NRRL B-2804 by solid state fermentation technology. Different agricultural solid waste substrates including Vigna radiate bran (green gram bran), Cajanus cajan bran (red gram bran), Cicer arietinum bran (black gram bran), and Glycine max bran (soyabean bran) have been screened in the study. Among the substrates studied Vigna radiate bran gave maximum production of L-Asparaginase of 0.67 U/gds. Parameters including inoculums media, seed age, percentage and concentration of impregnating media, fermentation period, cell disruption pH, cell disruption time, compositions of impregnating media, inoculums size, carbon source and nitrogen source were studied and optimized. The study showed maximum enzyme activity of 1.38 U/gds after one factor at a time optimization method. The parameters including Glycerol (0.5 % to 1.5 % w/w), L-Asparagine (0.5 % to 1.5 % w/w) and Tryptone (0.25 % to 0.75 % w/w) were optimized using Response Surface Methodology study (RSM) based on central composite design (CCD). By using the surface plots and response optimizer of Design Expert Version 6.0.8 (Stat-Ease, Minneapolis, MN 55413) software the maximum enzyme activity of 1.42 U/gds was obtained when glycerol, L-Asparagine and Tryptone concentration was 1.00 % w/w, 1.00 % w/w and 0.25 % w/w respectively. The ammonium sulphate precipitation gave purification factor (P. F. ) of 3.39 and on subjecting the obtained precipitate to dialysis followed by microfiltration and Ultra filtration the P. F. was increased to 5.76 times.