Jong Hoon Jeong

Platycosides from the Roots of Platycodon grandiflorum and Their Health Benefits

The extracts and pure saponins from the roots of Platycodon grandiflorum (PG) are reported to have a wide range of health benefits. Platycosides (saponins) from the roots of PG are characterized by a structure containing a triterpenoid aglycone and two sugar chains. Saponins are of commercial significance, and their applications are increasing with increasing evidence of their health benefits. The biological effects of saponins include cytotoxic effects against cancer cells, neuroprotective activity, antiviral activity, and cholesterol lowering effects. Saponins with commercial value range from crude plant extracts, which can be used for their foaming properties, to high purity saponins such as platycodin D, which can be used for its health applications (e.g., as a vaccine adjuvant). This review reveals that platycosides have many health benefits and have the potential to be used as a remedy against many of the major health hazards (e.g., cancer, obesity, alzheimer’s) faced by populations around the world. Methods of platycoside purification and analysis are also covered in this review.

Enhancement of 1-deoxynojirimycin content and α-glucosidase inhibitory activity in mulberry leaf using various fermenting microorganisms isolated from Korean traditional fermented food

Mulberry leaf is known to be effective in inhibiting increases in blood glucose levels in diabetic patients. 1-Deoxynojirimycin (DNJ), a α-glucosidase inhibitor, is the major effective component in mulberry leaf. The aim of this study was to evaluate the level of DNJ in mulberry leaves fermented by various microorganisms, including lactic acid bacteria, yeast, and the bacillus isolated from Korean traditional fermented soybean food, and to assess the inhibitory effect of fermented mulberry leaf powder extract (FMLE) on α-glucosidase activity. The DNJ content in unfermented mulberry leaf powder extract (UFMLE), the control, was determined to be 53.2 ± 1.5 mg/100 g (dry weight eq.). Lactobacillus plantarum, Zygosaccharomyces rouxii, Wickerhamomyces anomalus, and Bacillus subtilis remarkably increased the DNJ levels in mulberry leaves by 1.2, 1.5, 2.0, and 1.8-fold, respectively, compared to the control. The inhibitory effects of the FMLEs on α-glucosidase were also examined at various concentrations, and their α-glucosidase inhibitory effects tended to be higher than that in UFMLE. These findings suggest that Korean traditional fermenting microorganisms can be used as starter strains for the development of DNJ-enhanced food products, and that FMLEs have the potential to be used in various functional foods for the prevention of diabetes.