Phytochemical evaluation of lipoxygenase-free soybean genotypes for human consumption

Abstract The present study aimed to screen genotypes for the presence/absence of lipoxygenases and to evaluate the phytochemical characteristics of lipoxygenase-free genotypes. Progenies derived from the cross between the cultivars IAC PL-2 (with lipoxygenases) and BRS 213 (lipoxygenase-free) generated 114 inbred lines in the F6/7 generation, evaluated by the qualitative colorimetric method, to verify the presence/absence of lipoxygenase isoenzymes L-1, L-2 and L-3. Eight triple-null (lipoxygenase-free) lines were confirmed by visible spectrophotometry. Progenitors and triple-null lines IAC 10-0003-1, IAC 10-0010-1, IAC 10-0010-2, IAC 10-0012, IAC 10-0043, IAC 10-0046, IAC 10-0107-1 and IAC 10-0115-2 were analyzed to assess their contents of protein, oil, phytic acid, tannins, total phenols and total flavonoids. Analyses showed significant differences in protein (from 38.80% to 41.89%) and oil (from 18.86% to 22.88%), consistent with the values observed in commercial soybean cultivars. The new triple-null lines, compared to the BRS 213 standard, showed lower contents of soluble condensed tannins; lower phytic acid in line IAC 10-0043 and greater amount of total phenols in line IAC 10-0115-2; whereas, the lines IAC 10-0010-1, IAC 10-0010-2, IAC 10-0043, IAC 10-0046 e IAC 10-0107-1 stood out with higher values of total flavonoids. The new lines will be potentially useful parents for genetic breeding and for a multiline strategy, aiming at greater phenotypic stability of lipoxygenase-free soybeans for human consumption.