Enhancing the Production of Xanthine Oxidase by Adding Precursors of Coenzyme and Feeding Inducer

Abstract:

Based on sequence analysis of 16S rDNA and construction of phylogenetic trees, xanthine oxidase-producing strain in this work was identified as Arthrobacter globiformis. Xanthine oxidase(XOD) production was first enhanced by adding precursors of coenzyme(riboflavin and thiamine) and inducer(hypoxanthine, 3.6 g/L). In order to relieve inhibition for XOD production caused by hypoxanthine, two types of feeding protocols were investigated. The result indicated that feeding hypoxanthine to 3.6 g/L and adding 4.0 g/L glucose from 24 h made the XOD production achieved to 8 952.7 U/L, increased by 25.7%. And the average yield coefficient reached to 1041.0 U/g. It was found that high concentrations of ammonia(the end production of purine degradation) inhibited the xanthine oxidase fermentation.