Extraction and determination of functional properties of bioactive compounds from lotus leaves, and seed coats

Abstract

In this study, the total phenolic, total flavonoid and tannin contents, and the antioxidant activity of crude extracts from lotus seed coats and leaves using methanol and ethanol solvents were determined. The maximum total phenolic content of lotus leaves’ extract was 60.3 ± 1.4 mg FAE/g DW and that of lotus seed coats’ extract was 84.8 ± 1.1 mg FAE/g DW based on the optimization extraction condition. The total flavonoid content and tannin content of the lotus leaves extract were 53.6 ± 1.2 mg RE/g DW and 129.7 ± 1.6 mg/g DW, respectively, while the lotus seed coats’ extract had 49.3 ± 1.8 mg RE/g DW of total flavonoid and 204.5 ± 1.5 mg/g DW of tannin compounds. The results also indicate that the seed coats’ and leaves’ extracts exhibited strong antioxidant capacity which could reduce free radicals in human bodies. Furthermore, lotus leaves extract had higher inhibitory percentage of alphaglucosidase and also alpha-amylase (27.7 ± 1.4% and 42.03 ± 2.4 %, respectively) compared with lotus seed coats extract (17.95 ± 1.4% and 36.86 ± 2.9 %, respectively). Keywords: Nelumbo nucifera Lotus Total phenolic content Antioxidant activity