Optimization of Glucose Isomerase Production by Streptomyces roseiscleroticus from Soil

Bacterial isolate with glucose isomerase-producing ability was obtained from garden soil by means of starch casein agar as a selective medium. Morphological and microscopic analyses suggested the isolate belonged to the Streptomyces genus, and its identity was further confirmed as Streptomyces roseiscleroticus through 16S rRNA gene sequencing. The glucose isomerase production potential of the isolated strain was evaluated by employing 2, 3, 5-triphenyltetrazolium solution as a color-indicating agent. Optimization studies revealed that optimum glucose isomerase production was obtained at 37 oC and pH 7.0 after 120 hours of submerged fermentation. Significant enhancement in glucose isomerase production was observed with xylose (67.7 ± 2.00) as the preferred carbon source, a blended nitrogen source comprising peptone, beef extract, and yeast extract (36.7 ± 1.80), and tetra trimethyl ammonium bromide (67.7 ± 2.00) as the detergent facilitating enzyme extraction. The results imply that Streptomyces roseiscleroticus holds promise as a microbial source for industrial-scale glucose isomerase production, with potential applications in the manufacturing of high-fructose corn syrup (HFCS) as a sweetener and bioethanol as a renewable fuel.