Phytochemical compositions, antioxidant properties, enzyme inhibitory effects of extracts of four endemic Lathyrus L. taxa from Türkiye and a taxonomic approach

Lathyrus is an economically important genus, with different parts of some species used as foodstuff or animal feed. In this study, phytochemical compositions and bioactivities of Lathyrus brachypterus var. brachypterus, L. brachypterus var. haussknechtii, L. nivalis subsp. sahinii and L. tefennicus taxa which are endemic to Türkiye were investigated. Total phenolic and flavonoid contents (TPC, TFC) of methanolic extracts were detected. Then, phytochemical compositions, antioxidant features (radical scavenging (DPPH: 1,1-diphenyl-2-picrylhydrazyl, ABTS: 2,2'-azino-bis(3 ethylbenzothiazoline) 6 sulfonic acid), reducing power (FRAP:Ferric ion reducing antioxidant power, CUPRAC:Cupric ion reducing antioxidant capacity), metal chelating activity (MCA), and the phosphomolybdenum assays (PDA)) and enzyme inhibitory properties of the extracts were also determined. The highest values were found at L. brachypterus var. brachypterus for TPC, L. brachypterus var. haussknechtii for TFC. The highest antioxidant properties were seen in extracts of L. brachypterus var. brachypterus in DPPH, ABTS, FRAP, CUPRAC and PDA assays, while in extract of L. nivalis subsp. sahinii in MCA. The highest enzyme inhibitory activity was found in extract of L. brachypterus var. brachypterus in tyrosinase and glucosidase assays, while in extracts of L. nivalis subsp. sahinii in AChE (acetylcholinesterase), BChE (butyrylcholinesterase) and amylase. Finally, a taxonomic evaluation was made by considering the phytochemicals.