Study On Screening The Strain Gluconobacter Oxydans And Producing Intermediates Of N-alkyl-1-deoxynojirimycin By Bioconversion

In this paper, the strain G oxydans was separated from the selected samples obtained in nature, the conditions for G oxydans cultivation were studied. Continuously, the transformation conditions that l-deoxy-(2-hydroxyethyl amino)-D-glucitol and N- methyl-D-glucamine were microbiologically transformed to produce intermediates of N-alkyl-deoxynojirimycin by G oxydans, separation purification and analytical methods of the transformed products were researched.Through strain screening, G oxydans was obtained which had good growth status and strong transformation ability. The structure of l-Deoxy-(2-hydroxy-ethylamino)-D-glucitol and N-methyl-D-glucamine could be changed into 6-(2-hydroxyethyl)amino-6-deoxy- α -L- sorbofuranose and 6-methylamino-6- α -L- sorbo-furanose respectively by microbial transformation. The laters could be deoxidized to prepare α -glucosidase inhibitors: N-(2-hydroxyethyl)-l-deoxynojirimycin and N-methyl-1 -deoxynoj irimy cin.As a result, a plenty of desired cells could be obtained in a culture medium including mannitol and yeast extract et al, the suitable culture conditions were 28 ℃ 200rpm 27h. Temperature, pH, transformation time, concentration of substrate and resting cells have all relatively great influence on transformation ratio during the course of microbial transformation, especially the last three factors. Experiment showed: When pH is 5.0, the proportion of substrate and resting cells is 1:3, transformation can be finished in 8 hours at 30℃, and the transformation ratio can reach 99%.Transformed solution was inspected by TLC and carbonyl color-showed reaction in the course of biotransformation, and color-showed result was in focus. Products transformed were separated by methods of TLC and solvent deposition. The structure of products separated by solvent deposition were identified by IR and NMR, and proved they were the important intermediates of the compound: N-methyl-1-deoxyno-jinmycin.N-(2-hydroxyethyl)-l-deoxynojirimycin and N- methyl-1-deoxynojirimycin have much pharmacological activities, belonging to a -glucosidase inhibitors, especially Migilitol as safe and effective medicine has been used in treatment of diabetes type 2 for its remarkable decreasing blood glucose with less side effect.