Chemical Studies of Constituents of Sweet Plants Growing in Guangdong, China

从广东产的甜叶悬钩子（Rubus suavissimus，Rosaceae）的甜叶中分离得到一种甜二萜苷，命名为甜茶苷（Rubusoside）。在本研究中，这种甜味成分也从这种植物的果实中分离出来。沾益福盆子R. chingii）的形态与甘叶xuen-gouzi相似，但叶不甜。从该植物的叶中分离得到5个非甜二萜苷类化合物，分别命名为goshonosides F1-5。chingii（Gosho-ichigo）.这表明中国和日本R. chingii。从市售的民间药福盆子中鉴定出了罗汉果皂苷F5。这说明该民间药的原植物应该是以R.通过酶促转糖基化反应，改善甜茶苷（甜菊醇双葡萄糖苷）的甜度，并研究了甜茶苷的结构与甜度的关系。结果表明，以含水超临界CO2为萃取剂，几乎可以将甜菊叶中的甜菊醇苷完全萃取出来。黄芪（Engelhardtia chrysolepis，Junglandaceae）是一种原产于广东、广西、福建等地的中药，其叶味甜。从中国南方民间药材雪胆（Hemsleya carnosiflora）的叶中分离到一个新的顺式二氢黄酮醇鼠李糖苷（dihydroflavonol rhamnoside），同时还分离到两个已知的苷类化合物eucryphin和落新妇苷（astilbin），从其根茎中分离到六个新的葫芦烷苷类化合物，命名为carnosiflosides I-VI。Carnosiflosides V和VI味道甜，而II，III和IV味道苦，I没有味道。讨论了葫芦素苷类化合物的构味关系。

A sweet diterpene glycoside named rubusoside has been isolated from sweet leaves of Gan-yei xuen-gou-zi (Rubus suavissimus, Rosaceae) which grows in Guangdong, China. In the present study, this sweet principle was also isolated from fruits of this plant. Zhan-yei fu-pen-zi (R. chingii) is morphologically similar to Gan-yei xuen-gou-zi though the leaves are not sweet. From leaves of this plant collected in China, five non-sweet diterpene glycosides, goshonosides F1-5 were isolated, all of which have already been isolated from Japanese R. chingii (Gosho-ichigo). This indicates the chemotaxonomical identity of Chinese and Japanese R. chingii. Goshonoside F5 was identified in the commercial Fu-pen-zi, a Chinese folk medicine. This revealed that the source plant of this folk medicine must be represented by R. chingii.By means of enzymic transglucosylation, the sweetness of rubusoside (steviol bisglucoside) was improved and the structure sweetness relationship of glucosides of this type was investigated. It was found that by supercritical carbon dioxide containing water as an entrainer, the sweet steviol glycosides could be extracted almost completely from Stevia leaves.Huang-qi (Engelhardtia chrysolepis, Junglandaceae), a Chinese folk medicine grows in Guangdong, Guangxi and Fujian and its leaves taste sweet. From the leaves, a new cis-type dihydroflavonol rhamnoside was isolated together with the two known glycosides, eucryphin and astilbin.From rhizomes of Hemsleya carnosiflora, a folk medicine of South China, six new cucurbitane glycosides named carnosiflosides I-VI were isolated. Carnosiflosides V and VI taste sweet, while II, III and IV taste bitter and I has no taste. Stracture-taste relationship of cucurbitane glycosides was discussed.