Phenolic profile and antioxidant activity of thermally processed sponge gourd (Luffa cylindrica) as studied by using high performance thin layer chromatography (HPTLC)

Abstract

The effect of different extracting solvents (methanol, ethanol and butanol) and cooking treatments such as pressure cooking, microwave cooking and frying was studied in regards to phenolic profile and antioxidant activity of Sponge gourd (L. cylindrica). The antioxidant activity was investigated using different assays, namely, ferric thiocyanate test (FTC), thiobarbituric acid test (TBA), ferric reducing antioxidant power (FRAP) and DPPH free radicals scavenging test. A densitometric HPTLC analysis was performed for the analysis of phenolic acids and flavonoids. The inconsistent effect of cooking treatments on antioxidant potential was observed. In general, frying was most potent cooking treatments to retain the maximum antioxidant capacity. Correlation studies indicated that the phenolic compounds including flavonoids were mainly responsible for ferric reducing power, free radical scavenging activity and percent inhibition activity.