ANTI-NUTRIENTS AND BIOACTIVE COMPOUNDS IN DROUGHT RESPONSIVE NATIVE TEPARY BEANS

Phytonutrients are gaining importance due to their contribution towards healthy nutrition to eliminate the risk of cancer and heart diseases. Food legumes were one of the richest sources of these compounds. Tepary bean is drought tolerant food legume native to USA preferred by various native and international communities and not explored to date for its seed quality traits. Twelve drought responsive cultivars were evaluated to know the content of antinutrients and antioxidants and their interaction with seed coat color (cultivar). The cultivars with brown and black colored seed coats showing high antioxidant activity compared to those with white color. The cultivars showed significant (p<0.0001) variation for total phenolic content (0-6.59 mg of tannic acid equivalent/g), condensed tannins (0- 12.54 % leucocyanad in equivalent), total tannins (0-6.48 mg of tannic acid equivalent/g) and antioxidant activity (0.56- 19.72μmol/Trolox Equivalent/ g).Significant variation among the seed components and the cultivars was observed with high contents in seed coat followed by whole ground soaked seed, bean without seed coat and whole ground dry seed. The cultivars TB 4,7,18, 24, 29 were observed with high contents of phenols, tannins and antioxidant activity. The cultivars with high phenolic content are positively associated with high antioxidant activity and drought tolerance. The contents were high in seed coat compared to bean and whole seed due to accumulation of pigments and phenolic compounds in the seed coat and testa. The significant variation observed among cultivars indicated the genetic control of the trait to utilize in breeding new tepary varieties for these traits to produce healthy food grain by studying the nature of inheritance and heritability.