Ku Seockmo, You Hyun Ju, Park Myeong Soo, Ji Geun Eog
Department of Food and Nutrition, Research Institute of Human Ecology, Seoul National University, Seoul 08826, Republic of Korea.
Department of Hotel Culinary Arts, Yeonsung University, Anyang 14011, Republic of Korea.
J Microbiol Biotechnol. 2016 Jul 28;26(7):1206-15. doi: 10.4014/jmb.1601.01002.
Ginsenosides are the major active ingredients in ginseng used for human therapeutic plant medicines. One of the most well-known probiotic bacteria among the various strains on the functional food market is Lactobacillus rhamnosus GG. Biocatalytic methods using probiotic enzymes for producing deglycosylated ginsenosides such as Rd have a growing significance in the functional food industry. The addition of 2% cellobiose (w/v) to glucose-free de Man-Rogosa-Sharpe broths notably induced β-glucosidase production from L. rhamnosus GG. Enzyme production and activity were optimized at a pH, temperature, and cellobiose concentration of 6.0, 40°C, and 2% (w/v), respectively. Under these controlled conditions, β-glucosidase production in L. rhamnosus GG was enhanced by 25-fold. Additionally, whole-cell homogenates showed the highest β-glucosidase activity when compared with disrupted cell suspensions; the cell disruption step significantly decreased the β-glucosidase activity. Based on the optimized enzyme conditions, whole-cell L. rhamnosus GG was successfully used to convert ginsenoside Rb1 into Rd.
人参皂苷是用于人类治疗性植物药物的人参中的主要活性成分。功能食品市场上各种菌株中最著名的益生菌之一是鼠李糖乳杆菌GG。使用益生菌酶生产去糖基化人参皂苷（如Rd）的生物催化方法在功能食品工业中具有越来越重要的意义。向无葡萄糖的德氏改良罗氏沙氏肉汤中添加2%（w/v）的纤维二糖可显著诱导鼠李糖乳杆菌GG产生β-葡萄糖苷酶。酶的产生和活性分别在pH值6.0、温度40°C和纤维二糖浓度2%（w/v）的条件下达到最佳。在这些控制条件下，鼠李糖乳杆菌GG中β-葡萄糖苷酶的产量提高了25倍。此外，与破碎细胞悬液相比，全细胞匀浆显示出最高的β-葡萄糖苷酶活性；细胞破碎步骤显著降低了β-葡萄糖苷酶活性。基于优化的酶条件，全细胞鼠李糖乳杆菌GG成功地用于将人参皂苷Rb1转化为人参皂苷Rd。
