Composition of marama bean protein

Abstract

The protein composition of marama beans, an indigenous African oilseed legume, was determined in comparison with soya beans. Marama bean protein contained a substantial amount of tyrosine compared with soya bean protein. It was slightly richer in proline than soya. By SDS-PAGE, marama protein contained fewer protein bands compared with soya. The patterns of these bands in marama under non-reducing and reducing conditions were similar, suggesting an absence of disulphide bonds. The vicilin (7S) and acidic 11S subunits seemed to be absent in marama. This is most unusual in legume proteins. Only a major basic legumin (11S) (20 kDa), medium (63 kDa) and high (148 kDa) molecular weight protein bands were separated for marama. Most polypeptides in the marama proteome map are basic compared with soya. Only one polypeptide match was tentatively identified compared with soya. Marama protein composition is very different from that of soya.