Studies On The Chemical Constituents Of The Pericarps Of Citrus Grandis(L.) Osbeck And Its Pharmacological Activities

The plant Citrus grandis(L.) Osbeck (Rutaceae) is commonly known as pomelo orbuntan,.ect. The pomelo peel is the dried peel of the pummelo. Traditional Chinesemedicine believes that pomelo peel can be used in dissipating phlegm, promoting digestionand stopping coughing,.ect. Modern medical research shows: its extract exhibits widelybiological activities such as antioxidant, hypolipidemic, hypoglycemic, antibacterial,anticancer, cough expectorant, anti-inflammatory and analgesic and so on.Pummelo cultivation in China has a long history, rich in resources, and more varieties.In recent years, Citrus production area and volume are continuely rising, and some of thefamous varieties such as shatianyou, Guanxi honey pomelo have formed a large-scaleproduction, and gradually entering the international market. But most of pomelo peel afterprocessing and consumption are generally abandoned, resulting in waste of resources andpollution of the environment. In order to find out more chemical constituents in pomelo peeland to develop more new healthy maintenances and drug products, I gave comprehensiveresearches. The research methods and results are as follows:Firstly, pomelo peel was extensively extracted with75%alcohol. The combinedextracts were concentrated in vacuo until no-alcohol. Then I got the total extracts, whichwere extracted further by petroleum ether, chloroform, acetic ether and n-butyl alcohol inturn. By using silica gel column chromatography, HPLC, TLC and re-crystallizing methods,fourteen compounds were obtained. Among of them, ten compounds structures wereidentified with the chemical and spectral evidences (13C-NMR,1H-NMR, HMBC). Theyare Naringin(1), Naringenin-4’-O-glucoside(2), Aurapten(3), Umbelliferone(4)，Limonin(5),Friedelin(6), Dimethyl phthalate(7), Lauric acid(8), Sucrose(9), β-Sitosterol(10).Compound1～10were first obtained from the pericarps of Guanxi honey pomelo.The anti-inflammatory and analgesic effect of pomelo peel extracts was observed on dimethyl benzene-induced auricular edema and hot plate test in mice. The results indicatedthat the medium and high dose of pomelo peel extracts, compared with model group, hadsignificant anti-inflammatory effects; and compared with the blank group, both of themsignificantly prolonged the time of pain reaction in mice within two hours, and efficacyhave good continuity. So pomelo has certain anti-inflammatory and analgesic effect inanimal models.