Chemical composition and antioxidant activity of Allium flavum L. extracts

Members of the genus Allium have been used and cultured for thousands of years for their spiritual meaning, medicinal properties, pungency and characteristic taste. Only two species of genus Allium (A. sativum L. and A. cepa L.) are well researched, while data on the chemical composition and biological activities of other species, including Allium flavum L. are very rare. In the present study we investigated chemical composition and antioxidative properties of methanolic extracts of Allium flavum L. (subgen. Allium/sect. Codonoprasum) from five locations in Serbia. Phytochemical profile was determined by measuring total phenolic, total flavonoid and total anthocyanin content and by HPLC-DAD-MS/MS analysis of methanolic extracts of whole plants and headspace GC/MS analysis of volatile compounds of fresh bulbs. Flavor intensity associated with sulfur compounds was determined by measuring alliinase activity. The antioxidant activity was evaluated by measuring their 2,2-diphenyl-1-pycrylhydrazile (DPPH) radicals scavenging capacity, ferric reducing ability (FRAP) and effect on lipid peroxidation (LP). High contents of total phenolics (5.5–14.0mg gallic acid equivalents/g of dry extract) and total flavonoids (1.9–5.0mg quercetin equivalents/g of dry extract) were found, while anthocianin content was very low (11–33µg cyanidin-3-glucoside equivalents/g of dry extract). Allinase activity was found to be extremely high (28–48mg pyruvic acid/g of dry extract), while amount of volatile compounds was negligibly small. Chemical profile of methanolic extracts of A. flavum from different locations was independent of environmental conditions, only small differences in quantitative composition were found. Dominant flavonoid is dihexosyl quercetin. Investigated extracts exhibited high antioxidant activity.