【摘要】 将前期筛选到的一株产薯蓣皂苷水解酶的曲霉接种于添加薯蓣皂苷的产酶诱导培养基中,上5L发酵罐25℃培养。结果表明:残糖在4d后接近0,酶活力在6d达到最大,达到3385.14U/L。菌丝生物量和菌丝中积累的皂苷元总量也在6d达到最大。此时发酵液中薯蓣皂苷元含量为360μg/L,菌丝中薯蓣皂苷元含量为2285.28μg/g,菌丝生物量为5.15g/L。对酶的最适反应条件研究表明,50℃,10g/L皂苷底物,pH5.0时酶活力最大,酶解反应最佳时间为18h。该菌产生的酶有望代替酸水解工艺生产薯蓣皂苷元。更多还原

【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.更多还原