Fermentation pretreatment followed by two-phase combination acid hydrolysis for the extraction of diosgenin / 中国药学杂志

ABSTRACT

OBJECTIVE: To preliminarily establish the technology of fermentation pretreatment followed by two-phase combination acid hydrolysis for the extraction of diosgenin from the dry tubers of Dioscorea zingiberensis C. H. Wright. METHODS: Orthogonal experiment design was used with the yield of diosgenin as the monitoring index to optimize the conditions for fermentation pretreatment and two-phase combination acid hydrolysis. Two types of conventional methods were compared with the newly developed method. RESULTS: Fine powder of the tubers of Dioscorea zingiberensis C. H. Wright was mixed with water and fermented at 30°C for 72 h under stirring at 500 r · min-1, After that, sulfuric acid and methanol were added into the suspension to reach their final concentration of 10%, and petroleum ether was added to form a two-phase immiscible reaction system which was extracted in oil bath at 120°C for 4 h. As a consequence, the average yield of diosgenin achieved 4.28%, significantly higher than the 3.01% and 3.28% of the two conventional methods. CONCLUSION: This newly developed method of fermentation pretreatment followed by two-phase combination acid hydrolysis is proved to be more convenient than the traditional methods with a higher yield.