Evaluation of protein quality of sorghum [Sorghum bicolor (L.) Moench]

Abstract

Grain protein content varied from 6.8% to 19.6% in eight sorghum cultivars comprising land races,
\nhybrids, and local cultivars. Amino acid contents and distribution of Landry and Moreaux protein
\nfractions in grains were studied. Two Ethiopian land races had higher concentrations of lysine and
\nthreonine, as well as cystine, isoleucine, and tyrosine. Fraction I, comprising albumin-globulin including
\nnon-protein nitrogen, and fraction V (glutelin) together constituted about 41-55% of the protein
\nin the eight sorghum cultivars. Variation in fraction II (prolamin) and fraction III (cross-linked prolamin)
\ncontents was observed among the cultivars. To elucidate the pattern of synthesis of protein
\nfractions in grain, studies were made at different grain maturity periods, using one cultivar. Fraction
\nI synthesis was initiated at 7 days after anthesis. Prolamin increased from 14 to 28 days and declined
\ntoward maturity. Glutelin did not change beyond 14 days after anthesis until maturity