Analysis of physiochemical composition and antioxidant properties between hulls of the genetically modified glyphosate-tolerant soybean and northeast soybean

In this study, the physiochemical and antioxidant properties of the soybean hulls from the genetically modified glyphosate-tolerant soybeans (line 40-3-2) and local cultivar northeast soybeans were investigated. The levels of fat, total phenolic, total extractable pectin and soluble dietary fiber in northeast soybeans hulls were less than that in glyphosate-tolerant soybeans hulls, respectively. The antioxidant capacity of total phenolic, water soluble pectin, and soluble dietary fiber showed that DPPH free radical scavenging activities of glyphosate-tolerant soybeans hulls were 118.23, 57.34 and 197.22 μg AAE/g, which were 2.3, 1.2 and 9.4 times of northeast soybeans hulls, respectively (p < 0.05), and FRAP of glyphosate-tolerant soybeans hulls were 401.67, 747.51 and 328.53 μg AAE/g, which were 1.8, 8.7 and 4.8 times of northeast soybeans hulls (p < 0.05). Glyphosate-tolerant soybeans hulls extract showed the stronger antioxidant activity, which was positively correlated with total phenolic content (r = 0.890, p = 0.001). It provides evidence on developing value-added utilization of hulls, soybean processing by-products, as nutraceuticals or functional food ingredients.