Melatonin, phenolics content and antioxidant activity of germinated selected legumes and their fractions

Abstract

This study was aimed to evaluate the effects of germination process on melatonin, total phenols, total flavonoids and antioxidant activities of broad beans (Vicia faba L.), lupine seeds (Lupinus albus), chickpea seeds (Cicer arietinum L.), lentil seeds (Lens culimaris), fenugreek seeds (Trigonella foenum-graecum L.) and common beans (Phaseolus vulgaris) fractions (cotyledons, radicles and seed hulls). Radicle length of germinated legumes and sensory properties of legumes after 6 days of germination were also evaluated. Fenugreek and chickpea seeds had higher melatonin (54.22 and 24.42 ng/g), total phenols (5.79 and 5.68 mg gallic acid/g) and total flavonoids (8.86 and 8.43 mg quercetin/g), respectively than other legumes however, common beans showed the lowest values. Broad beans and lentil seeds had the highest antioxidant activities while lupine seeds showed the lowest value among all other legumes. The mean values of melatonin for cotyledons, radicles and seed hulls were increased by 386.26, 261.98 and 183.22%, respectively compared with the third day of germination. The increases in melatonin content of legume fractions were parallel to the increases in radicle lengths, total phenols, total flavonoids and antioxidant activities throughout the germination time. Overall acceptability of legumes had rating scores ranged between like moderately and like very much except for chickpea which had rating score described as like slightly. Keywords: Melatonin, Legumes, Germination, Radicle length, Total phenols