Abstract

• The aim of the present work is to investigate the phytoconstituents, the total phenolic contents, antioxidant activity, cytotoxicity, antiarthritic activity, and anti-diabetic activity of Litchi chinensis Sonn. (Lychee) peels. Preliminary phytochemical screening by test tube methods revealed that alkaloids, α-amino acids, carbohydrates, glycosides, organic acids, phenolic compounds, reducing sugars, saponins, starch, steroids, tannins, terpenoids and flavonoids are present and cyanogenic glycosides is absent in the sample. The total phenolic content of ethanol and watery extracts from Lychee peels was determined by the Folin Ciocalteu Reagent (FCR) method. Total phenolic content was found to be the highest in ethanol extract (114.86  0.14) μg/mL. In vitro antioxidant activity of ethanol and watery extracts of Lychee peels was assessed by the DPPH free radical scavenging assay. IC50 values were found to be 86.21 μg/mL for the watery extract and 31.03 μg/mL for the ethanol extract of Lychee peels. The cytotoxicity of the watery and ethanol extracts was evaluated by a brine shrimp lethality bioassay. From these results, the LD50 values of watery and ethanol extracts were found to be non-toxic at the 1000 μg/mL concentration. In vitro antiarthritic activity of watery and ethanol extracts was screened by the egg albumin method. According to the data, ethanol extract (IC50 = 60.56 μg/mL) has more potent antiarthritic activity than the watery extract (IC50 = 86.39 μg/mL). In vitro α-amylase inhibitory effect was determined by the starch-iodine method. The IC50 values were found to be 6.66 μg/mL for the watery extract and 5.83 μg/mL for the EtOH extract of the lychee peels.