以乙醇萃取及大孔树脂分离方法从罗汉果叶中提取出山奈酚-3,7-O-α-L-二鼠李糖苷。采用二苯代苦味酰自由基(DPPH)法和2,2-连氮-双-(3-乙基苯并噻唑啉-6-磺酸)(ABTS)法测定了山奈酚-3,7-O-α-L-二鼠李糖甙的自由基清除能力。结果表明:可以简便地从罗汉果叶中提取到纯度>60%的山奈酚-3,7-O-α-L-二鼠李糖苷粗品。山奈酚-3,7-O-α-L-二鼠李糖苷显示了良好的自由基清除活性,在DPPH自由基清除测定中,山奈酚-3,7-O-α-L-二鼠李糖甙的IC50值为9.08mg/mL;在对ABTS自由基清除能力测试中,山奈酚-3,7-O-α-L-二鼠李糖苷的IC50值为3.97mg/mL。

Kaempferol-3,7-O-α-L-dirhamnopyranoside was separated from Siraitia grosvenorii leaves using water extraction and macroporus resin adsorption methods.The free radical scavenging activity of kaempferol-3,7-O-α-L-dirhamnopyranoside was also determined.The results showed that kaempferol-3,7-O-α-L-dirhamnopyranoside could be easily obtained with >60% purity from Siraitia grosvenorii leaves.Furthermore,kaempferol-3,7-O-α-L-dirhamnopyranoside showed good free radical scavenging activity.The IC50 on DPPH was 9.08 mg/mL,and the IC50 on ABTS was 3.97 mg/mL.