| Uncaria genus consists of about 34 species, and mainly distributed in Southeast Asia, Australia, Africa and South America. Alkaloids, flavonoids, terpenoids and other compounds are the main chemical constituents of this genus. Pharmacological studies have shown that Uncaria genus has anti-hypertensive, anti-bacterial, anti-inflammatory, anti-tumor, neuroprotective effects. Uncaria scandens belongs to Uncaria genus (Rubiaceae) and used as traditionally Tibetan medicine. Dry stems with hooks named QiongDaiEr is used by the Tibetan doctors for the treatment of poisoning disease, headache, dizziness, high fever in children, seizures convulsions and so on. This paper deals with the investigation on the chemical constituents, antibacterial and antioxidant activity of Uncaria scandens.The phytochemical composition of Uncaria scandens were studied by variety of modern chromatographic separation methods and spectroscopic identification analysis.12 compounds were isolated and purified, the structure of 9 compounds were elucidated: Tetradecanal (1), Oleanolic acid (2), β-sitosterol (3), Ergosta-4,6,8 (14),22-tetraen-3-one (4),2-Hydroxydiplopterol (5), Ursolic Acid (6), Diisobutyl phthalate (7), Quercetin (8), 7-hydroxy-6-methoxycoumarin (9).In addition, the antibacterial activity of all the extracts was determined by Oxford cup method. The results showed that ethyl acetate extract A and B, petroleum ether, n-butanol fraction parts B have different degrees of inhibition on five tested bacteria, and its inhibitory effects were dose-dependent. While n-butanol extract B has no significant inhibition.DPPH radical and hydroxyl radical scavenging ability and reducing power were tested to evaluate the antioxidant activity of extracts from Uncaria scandens. The results showed that activity of ethyl acetate extract A is as good as vitamin C, while petroleum ether extract B shows the lowest activity.This thesis reviews the chemical constitutents and pharmacological activity of the genus Uncaria and describes the phytochemical research, antibacterial and antioxidant activity of Uncaria scandens. This research provides a scientific basis for the further development and utilization of Uncaria plant resources. |
