Quantitative Distribution of Tocopherol in Non-Transgenic Soybean Seeds

CARRERA C. S.; SEGUIN P.; LIU W.; FAN S.

Montreal

Conferencia; Canadian Society of Agronomy (CSA) and Canadian Society of Horticultural Science (CSHS) Annual Conference; 2016

Canadian Society of Agronomy (CSA) and the Canadian Society of Horticultural Science (CSHS)

Soybean seed contains several high-value health-beneficial compounds including tocopherols. Seed coats, soy germs, cotyledons, and whole seeds in six soybean cultivars grown at three sites were analyzed by high pressure liquid chromatography for α-, γ-, δ- and total tocopherol concentrations determinations. Cultivars differed in their α-tocopherol concentration as well as in their concentration of other tocopherols, ranking depending on the tocopherol; cultivar performance was, however, stable across sites. Seed parts was the most important source affecting variation for α-tocopherol concentration (71% of total variation), cultivars, and the cultivar × seed part interaction also had a significant effect (P < 0.001) but explained less than 12%. Tocopherol concentrations varied considerably between seed parts, α-, γ-, and total tocopherol concentrations being greater in the soy germ than in cotyledons; these differences were consistent across cultivars and sites. Cotyledons had, in contrast, greater δ-tocopherol concentrations. No tocopherols were detected in seed coats. Soy germs contained 332% more α-tocopherol than cotyledons, while cotyledons exhibited 200% more δ-tocopherol than soy germs and these differences were even higher in high α-tocopherol cultivars than low ones for both isomers. Results suggested that high α-tocopherol cultivars and their soy germs in particular may be a preferred source of α-tocopherol for the nutraceutical and functional food industries. While, their cotyledons with high concentrations of δ-tocopherol (known to exhibit the greatest relative antioxidant efficacy in seed of the four isomers) may protect the polyunsaturated fatty acid of the oil (mainly concentrated in this seed part) from lipid peroxidation.