SEARCH FOR ANTI-OBESE AND ANTIDIABETOGENIC PRINCIPLES FROM THE AYURUVEDIC NATURAL MEDICINES

在印度传统医学的阿育吠陀系统中，五层龙属已被用作糖尿病初始阶段的特定药物。研究发现，网脉蛇葡萄、长圆蛇葡萄和中华蛇葡萄根和茎的甲醇水提取物在大鼠中显示出降血糖活性和α-葡萄糖苷酶抑制活性。通过生物活性导向分离，得到了具有独特硫代糖硫鎓硫酸盐内盐结构的活性成分水杨酚和可他那醇。特别是，水杨酸的蔗糖酶和麦芽糖酶抑制活性（体外）和对蔗糖和麦芽糖负荷大鼠血清葡萄糖水平的抑制作用（体内）比作为α-葡萄糖苷酶抑制剂的商业药物阿卡波糖更有效。此外，研究还发现，网脉海棠的水提取物及其多酚类成分芒果苷具有抗肥胖活性。此外，从北五味子茎中分离得到7个新的三萜和2个新的倍半萜，其三萜组分具有抑制醛糖还原酶活性和清除自由基活性，朝鲜蓟甲醇提取物具有抗高血压活性，并分离得到几个倍半萜作为活性成分。对各种黄酮类化合物进行了上述筛选试验，并提出了几种结构-活性关系。

The genus Salacia have been used as a specific remedy at the initial stages of diabetes in the Ayuruvedic system of Indian traditional medicine. The aqueous methanolic extract from the roots and stems of S.reticulata, S.oblonga, and S.chinensis were found to show hypoglycaemic activity in rats and α-glucosidase inhibitory activity. By bioassay-guided separation, salacinol and kotalanol, which having the unique thiosugar sulfonium sulfate inner salt structures, were isolated as the active constituents. Particularly, sucrase and maltase inhibitory activities (in vitro) and inhibitory effects on serum glucose levels in sucrose-and maltose-loaded rats (in vivo) of salacinol were more potent than those of commercial medicine as α-glucosidase inhibitor, acarbose. In addition, the water extract of S.reticulata and its polyphenolic constituents indcuding mangiferin found to show anti-obese activity. Furthermore, seven new triterpenes and two new sesquiterpenes were isolated from the stems of S.chinensis and its triterpene constirutens found to show inhibit aldose reductase inhibitory activity and radical scavenging activities.The methanolic extract from artichoke exhibited anti-hyprelipidemic activity and several sesquiterpenes were isolated as the active components.To clarify structural requirements for aldose reductase, AGEs formation, and radical scavenging activities, various flavonoid compounds were examined above-mentioned screening tests and suggested several structure-activity relationships.