Chemical characterization of Passiflora edulis extracts and their in vitro antioxidant, anti-inflammatory, anti-lipid activities, and ex-vivo vasodilation effect

Abstract

Passion fruit is a dietary plant with the protective proterties against many diseases such as cardiovascular diseases. The aim of this study was to explore the biological properties (anti-oxidant, anti-inflammatory, anti-lipid, and vascular relaxation) of the P. edulis extracts obtained from seed (PSEE) and fruit (PFWE). Thin-layer chromatography (TLC) and HPLC were used to analyze the phytochemical constituents in the extracts. Antioxidant and enzyme inhibition properties were examined. Anti-inflammatory activities of PFWE and PSEE were evaluated in lipopolysaccharide (LPS)-induced macrophages and ex-vivo vascular relaxation were also determined. A high contents of piceatannol and polyphenolic stilbene were found in PSEE extracts. On the other hand, beta-carotene and gamma-tocopherol were predominant in PFWE. PFWE exhibited stronger anti-oxidant activity than PSEE. Both PSEE and PFWE showed significant inhibition of lipase and cholesterol esterase activities. However, only PFWE showed minimal inhibitory effect against HMG-CoA reductase. PSEE and PFWE caused a significant reduction of nitric oxide level in LPS-induced inflammation in RAW264.7 cells. Both extracts also showed ex-vivo vasorelaxation of rat aortic rings. It has been demonstrated that PFWE and PSEE possesses anti-oxidant activity, anti-inflammatory activity, pancreatic lipase and cholesterol esterase, and ex-vivo vasorelaxation of rat aortic rings, however, the activity of HMG-CoA reductase was inhibited by only PFWE. These findings suggest the beneficial effect of PSEE and PFWE against hyperlipidemia thus preventing the development of hypertension. However, further investigations in animal are needed to elucidate.

Keywords

• Passion fruit
• Nitric oxide
• HMG-CoA reductase
• Lipase
• Cholesterol esterase