Nontargeted metabolomics approach to determine metabolites profile and antioxidant study of Tropical Almond (Terminalia catappa L.) fruit peels using GC-QTOF-MS and LC-QTOF-MS

Abstract The objective of the present study was to identify the metabolome pattern and study the biological efficacy of Almond ( Terminalia catappa L.) peels. In the present study, metabolite profiling was carried out using GC-QTOF-MS and LC-QTOF-MS techniques, from the potent extract showed highest antioxidant efficacy. Antioxidant efficacy of the various extracts derived by six different extraction methods was assessed by different assays viz. 2,2-diphenyl-1-picrylhydrazyl, superoxide, 2,2′-Azino-bis-(3-ethyl)benzothiazoline)-6-sulfonic acid diammonium salt radical cation inhibition assays and ferric reducing antioxidant power. The methanolic maceration extract showed significant antioxidant activity in all assays and richest source of flavonoid content. The results showed that the extraction method significantly altered the antioxidant activity. The correlation between the antioxidant activities and total flavonoid content were ranging between 0.939 to 0.628. Methanolic maceration extraction method proved to be the best extraction method for the extraction of antioxidant. During the metabolite profiling employed by GC-QTOF-MS and LC-QTOF-MS and total 24 and 53 compounds belongs to different groups were detected and identified, will help to uncover the relation with potent antioxidant activity.