Department of Integrative Bioscience and Biotechnology, Konkuk University, Seoul 05029, Republic of Korea.
Department of Bioscience and Biotechnology, Konkuk University, Seoul 05029, Republic of Korea.
J Microbiol Biotechnol. 2022 Apr 28;32(4):430-436. doi: 10.4014/jmb.2112.12020.
Platycosides, Platycodi radix ( root) saponins, are used as food supplements and exert diverse pharmacological activities. Deglycosylation of saponins enhances their biological efficacy, and deglycosylated platycosides are produced mainly through enzymatic hydrolysis. However, the types of available deglycosylated platycosides remain limited because of a lack of hydrolyzing enzymes that can act on specific glycosides in glycosylated platycosides. In this study, a crude enzyme from converted platycoside E (PE) and polygalacin D (PGD3) into deglucose-apiose-xylosylated (deGAX)-platycodin D (PD) and deGAX-polygalacin D (PGD), respectively. The products were identified through LC/MS analysis by specifically hydrolyzing all glucose residues at C-3, and apiose and xylose residues at C-28 of platycoside. The hydrolytic activity of the crude enzyme obtained after the cultivation of the fungus using citrus pectin and corn steep solid as carbon and nitrogen sources, respectively, in culture medium was increased compared with those using other carbon and nitrogen sources. The crude enzyme from was the most effective in producing deGAX platycoside at pH 5.0 and 60°C. The crude enzyme produced 0.32 mg/ml deGAX-PD and 0.34 mg/ml deGAX-PGD from 1 mg/ml PE and 1 mg/ml PGD3 (at pH 5.0 and 60°C) for 12 and 10 h, with productivities of 32.0 and 42.5 mg/l/h and molar yields of 62.1 and 59.6%, respectively. To the best of our knowledge, this is the first study to produce deGAX platycosides from glycosylated platycosides.
远志皂苷是一种常用的药食同源物质，具有多种药理活性。皂苷的去糖基化可以提高其生物活性，目前主要通过酶解法制备去糖基化的远志皂苷。然而，由于缺乏能够作用于糖基化远志皂苷中特定糖苷键的水解酶，可用的去糖基化远志皂苷的种类仍然有限。本研究中，从 中提取的粗酶可分别将远志皂苷 E（PE）和远志三糖苷 D（PGD3）水解成去葡萄糖-阿魏糖-木糖基远志皂苷 D（PD）和去葡萄糖-阿魏糖-木糖基远志三糖苷 D（PGD）。通过 LC/MS 分析特异性水解远志皂苷 C-3 位上的所有葡萄糖基、C-28 位上的阿魏糖基和木糖基，对产物进行了鉴定。与使用其他碳源和氮源相比，真菌在以柑橘果胶和玉米浆固体为碳源和氮源的培养基中培养后获得的粗酶的水解活性更高。在 pH 值为 5.0 和 60°C 的条件下， 产生的粗酶最有利于生成去葡萄糖-阿魏糖-木糖基远志皂苷。该粗酶在 12 和 10 h 内可分别从 1 mg/ml 的 PE 和 1 mg/ml 的 PGD3 中产生 0.32 mg/ml 的去葡萄糖-阿魏糖-木糖基远志皂苷 D 和 0.34 mg/ml 的去葡萄糖-阿魏糖-木糖基远志三糖苷 D，产物生成率分别为 32.0 和 42.5 mg/l/h，摩尔收率分别为 62.1%和 59.6%。据我们所知，这是首次从糖基化远志皂苷中制备去葡萄糖-阿魏糖-木糖基远志皂苷。
