Comparative study on the phenolic content, antioxidant properties and HPLC fingerprinting of the leaf extracts of Clerodendrum volubile P. Beauv

The present study aimed to investigate the phenolic contents and antioxidant properties of the various leaf extracts (methanol, ethanol, ethyl acetate) of Clerodendrum volubile. The total phenol and total flavonoid contents of the extracts were determined. In vitro scavenging activities of the extracts were assessed against 1, 1-diphenyl-2 picrylhydrazyl (DPPH), 2, 2-azinobis (3-ethylbenzo-thiazoline- 6-sulfonate (ABTS) radical scavenging ability. The reducing power ability and high-performance liquid chromatography-diode-array detector (HPLC-DAD) of the extracts were also determined. The results revealed that methanolic extract had the highest total phenol and total flavonoid contents in all the extracts. The methanol extract had the highest reducing power, DPPH and ABTS radicals scavenging activities, followed by ethanol and ethyl acetate extracts. The HPLC-DAD results revealed the presence of both phenolic acids (caffeic acid, gallic acid) and flavonoids (catechin, quercetin, rutin, quercitrin, kaempferol, luteolin, apigenin) as its major bioactive polyphenolics. The difference in scavenging potential of the extracts may be due to variation in the phytoconstituents extracted using various solvents. The result suggests that the methanol leaf extract of Clerodendrum volubile could serve as a potential source of antioxidants and can be explored as a therapeutic agent in free radical induced diseases.