FOOD SCIENCE ›› 2007, Vol. 28 ›› Issue (8): 269-272.

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Study on Fermentation and Properties of Crude Enzyme Hydrolysing Dioscin

 ZHAO  Yu-Ting, XU  Zeng-Lai, DAI  Chuan-Chao, WANG  Qiong, TIAN  Lin-Shuang   

  1. 1.College of Life Science, Nanjing Normal University, Nanjing 210097, China;2. Institute of Botany, Jiangsu Province and Chinese Acadamy of Sciences, Nanjing Botanical Garden Mem. Sun Yat-sen, Nanjing 210014, China
  • Online:2007-08-15 Published:2011-10-24

Abstract: A strain of Aspergillus sp. which could produce dioscin hydrolyzing enzyme was inoculated into medium adding elicitors of total saponin and cultured at 25 ℃ in 5 L fermentor. The results showed that the reducing sugar got near to zero at 4 d and enzyme activity got highest at 6d (3385.14 U/L). The biomass and the total diosgenin get highest at 6d. At the time, the diosgenin at the filtered liquid and mycelia got 360μg/L and 2285.28μg/g respectively. The highest biomass got 5.15 g/L. Enzymatic reaction conditions were optimized: the optimum temperature and pH for the enzyme were determined as 50 ℃ and 5.0 respectively. The enzymatic activity was the highest with saponin of 10 g/L. The best time of enzymatic reactions was 18 h. The enzyme hydrolysis of the dioscin would substitute the acid hydrolysis hopefully in the future.

Key words: dioscin hydrolyzing enzyme, Aspergillus sp., fermentation, properties of enzyme, diosgenin