Isoflavone 7-O-glucosyltransferase converting daidzein to daidzin, genistein to genistin and formononetin to ononin (PubMed:24700248). Shows some activity toward the chalcone isoliquiritigenin, the flavanones liquiritigenin and naringenin, and the flavone apigenin, but not toward cyanidin, luteolin, kaempferol, quercetin, daidzin and puerarin (PubMed:24700248). a 7-hydroxyisoflavone + UDP-alpha-D-glucose = a 7-hydroxyisoflavone 7-O-beta-D-glucoside + H(+) + UDP kcat is 1.1 sec(-1) with daidzein as substrate. kcat is 1.1 sec(-1) with genistein as substrate. Expressed in roots. Detected in stems and leaves. Up-regulated by methyl jasmonate. Belongs to the UDP-glycosyltransferase family.