Novel Biotransformation Process Of 4'-demethylepipodophyllotoxin To 4'-demethylepipodophyllic Acid

For the first time,the biotransformation process of 4'-demethylepipodophyllotoxin to demethylepipodophyllic acid was developed in this work.The performance of the biotransformation process was improved by the study on its kinetics and optimization.Firstly,based on the capability of modifying 4'-demethylepipodophyllotoxin structure,4 trains(i.e,Bacillus fusiformis CICC 20463,Bacillus subtilis CCTCC AB93174,Pseudomonas aeruginosa CCTCC AB 9306 and Pseudomonas oleovorans CGMCC 1.1641) were screened out from 8 tested strains.Among them,B.fusiformis was selected for the following study because of its high substrate conversion. Biotransformation product was separated from the biotransformation borth by macroporous resin D312,and identified as 4'-demethylepipodophyllic acid by the comparison analysis of EI-MS and NMR spectrums with 4'-demethylepipodophyllotoxin.So,the biotransformation process from 4'-demethylepipodophyllotoxin to 4'-demethylepipodophyllic acid was set up.Secondly,dynamics and optimization of biotransformation process were investigated.The results show that maximum 4'-demethylepipodophyllic acid concentration(2.81±0.21 mg/L) was obtained at 5.0 g/L yeast extract and 10.0 g/L peptone;4'-demethylepipodophyllic acid concentration was enhanced as sucrose increasing in this study,and 2.94±0.17 mg/L 4'-demethylepipodophyllic acid was obtained at 40.0 g/L sucrose;3 g/L sodium chloride is harmful for cell growth but help to the production of 4'-demethylepipodophyllic acid(4.10±0.18 mg/L);100 mg/L 4'-demethylepipodophyllotoxin is suitable for the production of 4'-demethylepipodophyllic acid(6.47±0.35 mg/L).It is notable that 4'-demethylepipodophyllic acid concentration was influenced by pH obviously, maximum 4'-demethylepipodophyllic acid concentration was increased to 38.78 mg/L at pH 9.0.The biotransformation technology was firstly applied in the structure modification of 4'-demethylepipodophyllotoxin,and more solulable biotransformation product (4'-demethylepipodophyllic acid) was produced.The biotransformation process was developed and optimized,and increased 4'-demethylepipodophyllic acid concentration obviously.This work gave a new way to the structure modification of 4'-demethylepipodophyllotoxin,promoted the application of biotransformation technology in the modification of chemicals and provided references to modification of other chemicals.