A Novel Soy Isoflavone Derivative, 3′-Hydroxyglycitin, with Potent Antioxidant and Anti-α-Glucosidase Activity

This study demonstrated the enzymatic hydroxylation of glycitin to 3′-hydroxyglycitin, confirming the structure by mass and nucleic magnetic resonance spectral analyses. The bioactivity assays further revealed that the new compound possessed over 100-fold higher 1,1-diphenyl-2-picrylhydrazine free-radical scavenging activity than the original glycitin, although its half-time of stability was 22.3 min. Furthermore, the original glycitin lacked anti-α-glucosidase activity, whereas the low-toxic 3′-hydroxyglycitin displayed a 10-fold higher anti-α-glucosidase activity than acarbose, a standard clinical antidiabetic drug. The inhibition mode of 3′-hydroxyglycitin was noncompetitive, with a K(i) value of 0.34 mM. These findings highlight the potential use of the new soy isoflavone 3′-hydroxyglycitin in biotechnology industries in the future.