Volatile compounds, antioxidants, and anticancer activities of Cape gooseberry fruit (Physalis peruviana L.): An in-vitro study

Abstract

Background/aim Cape gooseberry is golden-colored spherical fruit commercially produced in Egypt. It is primarily used in folk medicine for treating some diseases. To identify the aroma compounds in Cape gooseberry and to evaluate its antioxidant activities as well as its anticancer (for colon and breast cancers) effects in human cell lines. Materials and methods The volatile compounds were identified using gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS). Polyphenols (phenolics and flavonoids) were also determined. Antioxidant activity was determined by three different methods: 2,2΄-diphenyl-1-picrylhydrazyl (DPPH), 2,2-azinobis(3-ethyl-benzothiazoline-6-sulfonic acid) (ABTS), and ferric reducing antioxidant power (FRAP) assays. Anticancer (for colon or breast cancer) activity was determined in cancer cell lines using 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay. Results A total of 34 components of the essential oil were identified by GC and GC-MS. The volatile compounds were grouped in classes of substances, including 11 terpene compounds (six monoterpenoids and five sesquiterpene), 11 esters, five alcohols, two phenolic compounds, two aldehydes, two ketones, and one lactone. Terpenes (monoterpenes and sesquiterpenes) were the most abundant volatile constituents, accounting for the largest portion of the total volatiles (36.09%). The next most abundant compounds were esters, comprising 17.17% of the total volatile components identified. Phenolic compounds were the next most abundant compounds, comprising 16.04% of the total volatiles. Alcohols and aldehydes represented 6.37 and 1.88% of the total volatile compounds, respectively. Ketones and lactones are less abundant in the profile of volatile compounds in Cape gooseberry. Ethanol extract had higher phenolic and flavonoid contents than did hexane extract. As ethanol extract of Cape gooseberry achieved higher antioxidant activity than did hexane extract, it tested as an anticancer (for colon or breast cancer) agent. Cape gooseberry extract was more potent in inhibiting colon cell lines (IC 50 : 142 μg/ml) compared with breast cell line (IC 50 : 371 μg/ml). Conclusion Egyptian Cape gooseberry fruits may be suggested as a potential source of natural antioxidants and anticancer agents.