Cayratia trifolia is a medicinal plant, with a range of traditional uses including anti-microbial, analgesic, anti-inflammatory, hypoglycemic, anticancer, and so on. It could be a potential source of new drug discovery. This study aimed to isolate and purify metabolites of C. trifolia, elucidate their structures, and evaluate analgesic and anti-inflammatory activities. The dried leaves (1.0 kg) of C. trifolia were extracted with methanol which yielded 40.0 g of crude extract. TLC-guided repeated silica-gel column chromatography of the extract with increasing polarity of dichloromethane-ethyl acetate-acetone step gradient yielded compounds CT_01 (577 mg), CT_02 (121 mg), and CT_03 (255 mg). The 1D and 2D-NMR spectra of purified metabolites were recorded on a 400 MHz instrument. Analgesic and anti-inflammatory activities of these isolated compounds were assessed in Swiss albino male mice (n=5/group) using acetic acid-induced writhing and carrageenan-induced paw edema methods, respectively. The structures of the purified metabolites were elucidated with ¹H- and ¹³C-NMR spectral analysis and confirmed by comparing the data with published data in the literature. CT_01, CT_02, and CT_03 were identified as Stigmast-5-en-3-O-β-D-glucoside, oleic acid β-D-glucoside, and campesterol, respectively. The mice were treated orally with several doses of MeOH extract and pure compounds prior to the pain and edema induction. Significant inhibition of pain sensation was observed in MeOH-extract (p<0.01, p<0.0001) and CT_02 (p<0.05, p<0.001) treated mice in a dose-dependent manner and in CT_01 (p<0.05) and CT_03 (p<0.001) treated mice at a lower dose when compared to the mice of negative control. The volume of paw edema was also reduced at a significant level by 70-80% in CT_01 and CT_02 treated mice after one hour (p<0.0001) and two hours (p<0.01), and by 37.5-58.75% and 16.67-44.44% in CT_03 treated mice after one hour (p<0.05, p<0.001) and two hours of carrageenan induction. C. trifolia leaves as well as CT_02 are promising in managing pain and inflammation, warranting further research with it.

Adam Safiullah

Appearances