人参是一种古老的草药，用于东方医学治疗各种疾病。皂甙是人参的主要生物活性成分，但其分子上的多个葡萄糖基侧链阻止了人参皂苷通过肠膜进入血液，从而降低了功效。通过体外去除自然人参皂苷的糖基，制备易于被人体吸收并具有更高药物活性的稀有人参皂苷已被广泛实践。稀有人参皂苷Rg3和Rh2已被批准作为药物或保健品，以提高免疫功能。本文综述了近年来人参皂苷Rg3和Rh2的制备方法。利用原皂苷的生物转化法制备了人参皂苷Rg3和Rh2，实验室中的最高转化率分别为98.19％和95.89％。目前，提高转化率和降低生产成本仍是通过从人参粗提物中直接去糖基的Rb1、Rb2、Rb3、Rc和Rd进行Rg3和Rh2的工业规模生产的瓶颈。此外，通过激活AMPK，JNK，NF-κB，MAPK，P13K/AKT/mTOR等信号通路，人参皂苷Rg3和Rh2表现出抗炎、抗癌、心血管保护、免疫调节、神经保护、抗糖尿病、抗疲劳、抗过敏、抗衰老、抗氧化等药理作用。作为预防和治疗各种疾病的潜在药物，人参皂苷Rg3和Rh2需要通过体外和体内实验进一步澄清其他潜在机制。版权所有©2023 Elsevier B.V出版。

Ginseng, an ancient medicinal herb, is used in oriental medicine for the treatment of various diseases. Saponins are the main bioactive components of ginseng, but the multiple glucosyl side chains on its molecules prevent ginsenosides from entering the blood through the intestinal membrane, thus reducing the efficacy. The preparation of rare ginsenosides, which are easy to be absorbed by human body and have higher drug activity, has been widely practiced by removing the sugar group of natural ginsenosides in vitro. Rare ginsenosides Rg3 and Rh2 have been approved as drugs or health supplements to improve immune function. This review summarizes the preparation methods of ginsenoside Rg3 and Rh2 in recent years. Ginsenoside Rg3 and Rh2 were prepared by biotransformation of protopanaxadiol type ginsenoside, with the highest conversion rate of 98.19% and 95.89% in the laboratory, respectively. At present, improving the conversion rate and reducing the production cost are still the bottleneck of industrial scale production of Rg3 and Rh2 through the deglycosylation directly from Rb1, Rb2, Rb3, Rc and Rd in the crude extract of ginseng. In addition, ginsenosides Rg3 and Rh2 play anti-inflammatory, anticancer, cardiovascular protective, immunomodulatory, neuroprotective, anti-diabetic, anti-fatigue, anti-allergic, anti-aging, antioxidant and other pharmacological effects by activating AMPK, JNK, NF-κB, MAPKs, P13K/AKT/mTOR and other signaling pathways. As potential drugs for prevention and treatment of various diseases, ginsenoside Rg3 and Rh2 need to further clarify other underlying mechanisms of action through in vitro and in vivo experiments.Copyright © 2023. Published by Elsevier B.V.