Physicochemical and structural properties of major protein fractions of two varieties of nea-cowpea (vigna unguiculata l.): a comparative study

Abstract

In both cowpea varieties, the globulin was the major protein fraction followed by albumins, glutelins and prolamins with 48 ± 2 g/100 g, 33 ± 2 g/100 g, 8 ± 1 g/100 g and 2 ± 0.5 g/100 g of the total seed protein content, respectively. Under non-reducing conditions, the CU and CO globulin fractions, showed four major polypeptides with molecular masses of 80 ± 3, 65 ± 3, 56 ± 2 and 52 ± 2 kDa and some polypeptides with molecular masses ranging 45-25 kDa. Albumin and globulin fractions of CU showed the lowest values of enthalpy (H) suggesting an initial partial denaturation. Globulin fraction showed a higher content of aromatic amino acids than the albumin fraction, displaying a more hydrophobic behaviour. Results provide useful data that will be supplemented with further studies on functional properties of these proteins fractions, followed by the development of legume protein products.