Enzymatic Studies Of Oligoxanthan Degraded By Xanthase From Sphingomonas Sp. Strain XT-11

Oligosaccharides are important informational molecules and widespread existence in human body. They participate in many kinds of vital activity in life. They also have a lot of bioactivities since their complicated configuration. Xanthan gum is the most important microbial polysaccharide commercial, however, its degradation products'biological activities is rare reported until now.According to its morphology, cultural properties, physiological characteristics and 16S ribosomal RNA gene sequence, we analyzed a strain of facultative anaerobe XT-11 for producing xanthase which was isolated from microorganism in the soil. Compared with the sequence in the Genbank, most strain which have homology more than 99% are Sphingomonas sp. The strain is conserved in Chinese General Microorganism Conserve Center now(CGMCC NO.1421).The effects of different factors on the enzyme production were studied. Glucose and (NH₄) NO₃ were the preferable C and N source, respectively. The optimized initial pH for the strain growth and producing xanthase was about 7.0. The optimized temperature for the strain growth and producing xanthase was about 30℃.The bacterium cultured in 250ml flask with 30ml of the medium in it was preferable. The amount of inoculums was not an important factor for the result of fermentation.Oligoxanthan's biological activities were also explored. The results showed...