Comparative investigation on metabolites changes in soybean leaves by ethylene and activation of collagen synthesis

Abstract Genistein and daidzein are predominant phytoestrogens for an estrogen alternative due to their higher receptor binding affinity. The present study illustrated the effective method to produce isoflavone riched soybean leaves (IRSL). Notably, ethylene application to soybean leaves under dark condition led a distinctive increase in genistin, daidzin, malonylgenistin and malonyldaidzin, which raised to total 25,911 μg/g of isoflavones in comparison to control leaves (>200 μg/g). Genistin and daidzin derivatives were enhanced with 120-fold (123→14,996 μg/g) and 185-fold (59→10,916 μg/g), respectively. The changes in metabolites by ethylene were systematically identified by UPLC–ESI-TOF/MS to give successfully PLS-DA score and heatmap analysis. The identified nine isoflavones were markedly increased, whereas rest main metabolites, kaempferols and soyasaponins were not affected. Furthermore, in contrast to the control leaves, the IRSL extract showed stimulation of collagen synthesis and induced gene expressions, in particular COL1A1 and COL3A1, in human dermal fibroblast.