Studies On Rubusoside And Other Chemical Constituents In Leaves Of Rubusoside Suavissimus S. Lee

Rubus Suavissimus S.Lee., a perennial shatter shrub of rosaseae family growing wildly in Guilin, Liuzhou, Wuzhou, et al., is a sweet plant native to Guangxi Province. It is reported that sweet tea"has actions of reducing a fever, moistening a lung, relieving a cough, and reducing the phlegm". And it is widely used in medicament, beverage, and food industry. To better exploit and make good use of this plant, further research of its leaves was considered in this paper from the following four parts:1,Rubusoside,polyphenolic compounds,amino acid and flavonoids were found in water extract. Rubusode and two kinds of flavonol named quercetin and kaemplenol were confirmed in the extract and the hydrolysate of those extracts by their retention times in RP-HPLC employing UV-Vis detection, respectively. And the target aglycones were isolated from the hydorlysate by silica gel column chromatography and recrystallization. The results showed that the flavonoids whose aglycone was quercetin or kaempferol were firmly proved in the extract.2,The contents of rubusoside and flavonoid aglycones, and the antioxidant capacities of total flavones in Rubusoside Suavissimus S. Lee leaf extracts were determined by means of High Performance Liquid Chromatography and the formation of phosphomolybdenum complex, respectively. The results indicated that the total flavone in Rubusoside Suavissimus S.Lee leaf extracts was better radical scavenger than BHT.3,We have produced a monomer from leaves of Rubus Suavissimus S.Lee, using methods of water extraction,column chromatogramphy and recrystallization. And such a simple and rapid method provides considerable conveniences for content determination of rubusoside in industrial products, activity researchs on the monomer of rubusoside and its pharmacokinetics in vivo, as well as beneficial references for industrial preparation of high purified rubusoside.4,The dried leaves of of Rubus Suavissimus S.Lee were extracted with water and then chromatographed on a highly porous synthetic polymer eluting by75% EtOH and refining by absolute alcohol to get water extract.Thus, a susepension of this extract was chromatographed on polyamide and silica gel with recrystallization purification to obtain six compounds except for rubusoside, the main constitute. Of these compounds, one is palmitic acid; another is Quercetin-3-β-D-galactoside, and the rest four are diterpene glucosides:13-O-β-D-glucosyl-steviol, ent-16,17-dihydroxy-3-one-kaurane-17-O-D-glucoside, steviol, ent-16α-17-dihydroxy-kanuran-19-oic acid. Their structures were elucided mainly on the basis of IR and NMR spectral evidence. And there was no report on the isolation of palmitic acid, flavonoide(Quercetin-3-β-D-galactoside),and steviol from water extract of Rubus Suavissimus S.Lee leaves in literature.