Antioxidant Capacity of Alcalase Hydrolysates and Protein Profiles of Two Conventional and Seven Low Glycinin Soybean Cultivars

Abstract

Soy protein hydrolysates are considered a potential dietary source of natural antioxidants with important biological activities. This study was conducted to compare the effect of two conventional and seven low glycinin soybean cultivars on the antioxidant capacity (AC) of soy hydrolysates. Nine cultivars were grown in Bloomington, IL, Findlay, OH and Huxley, IA. The hydrolysates were produced enzymatically using alcalase and analyzed for AC using oxygen radical absorbance capacity (ORAC) assay and soluble protein. Statistical differences were observed in the protein profiles and AC among the different cultivars tested (P < 0.05). The hydrolysate from low glycinin cultivar 3 enriched in β-conglycinin, grown in Bloomington, exhibited the highest AC, compared to the other cultivars across all locations. On average, soy cultivars rich in BC and purified BC hydrolysates (36.2 and 31.8μM Trolox equivalents (TE)/μg soluble protein, respectively) (P > 0.05) had higher AC than purified glycinin (GL) hydrolysate (28.5μM TE/μg soluble protein) (P < 0.05). It was possible to select a soybean cultivar that produced a higher antioxidant capacity upon alcalase hydrolysis.