Isolation and screening of xanthine oxidase producing bacteria from thermal springs of himachal pradesh

Xanthine oxidase is a highly versatile and ubiquitous complex molybdoflavoprotein and has catalytic role in purine degradation, metabolizing hypoxanthine and xanthine to uric acid with the generation of superoxides. In the present study, Nitrobluetetrazolium (NBT) based colorimetric assay was used to screen the xanthine oxidase producing microorganisms from the soil and water samples of thermal springs of Himachal Pradesh, India. A total of fortyisolates were obtained on primary screening of xanthine oxidase producing microorganisms. The hyper-active bacterial isolate RL-2d, isolated during the screening has been identified by physiological and biochemical tests as Bacillus sp. and named Bacillus sp. RL-2d. The present study showed that Bacillus sp.RL-2d exhibited highest xanthine oxidase activity among all the isolates screened for xanthine oxidase.