Anti-inflammatory Activity and Isolation of Luteolin from Plagiochasma appendiculatum Methanol Extract

Abstract

Plagiochasma appendiculatum, a flavonoid rich liverwort, is reported to be used in the treatment of cuts, burns, outside wounds, bacteriostatic, pulmonary tuberculosis, neurasthenia, fractures, convulsions, scalds, uropathy, and inflammation by tribal communities. In the present study, flavonoid luteolin, reported to possess anti-inflammatory potential, is isolated from P. appendiculatum methanol extract and extract is evaluated for anti-inflammatory effect. Anti-inflammatory potential was studied by protein denaturation assay and carrageenan-induced rat paw edema method. Plant flavonoid is isolated from methanol extract by column chromatography, using petroleum ether and ethyl acetate in various proportion, as mobile phase. Further identified by spectroscopic analysis. In vitro studies, at a concentration of 800 μg/ml, P. appendiculatum methanolic extract (PAME) exhibited 74% inhibition while indomethacin showed 79% inhibition at the same concentration. The extract exhibits a decrease in inflammation in rat hind paw when tested with carrageenan-induced paw edema. PAME at a dose of 150 mg/kg displayed the most potent anti-inflammatory activity compared to the other groups during the course of the observation period. The methanol extract yielded a yellow color crystalline compound which is characterized as 2-(3,4-Dihydroxyphenyl)-5,7-dihydroxy-4-chromenone, commonly known as luteolin. Isolation of luteolin from P. appendiculatum is first time reported, which supports the ethnobotanical claims and provides scientific explanation for anti-inflammatory use of mentioned liverwort.