Cucurbitane glycosides from the fruit of Siraitia grosvenori and their effects on glucose uptake in human HepG2 cells in vitro.

The mogrosides in the fruit of Siraitia grosvenori can serve as a sugar substitute for diabetics due to their sweetness, low calorie and positive effects on blood glucose level control. The present study was to purify the mogrosides from the fruit of S. grosvenori and evaluate their enhancement of glucose uptake rate in HepG2 cells in vitro. As a result, eighteen mogrosides were isolated, including six new ones and a known but new naturally occurring compound. The chemical structures of the new compounds were identified by 1D, 2D-NMR and HR-ESI-MS techniques, together with chemical methods. Compared to the positive control (metformin), all the obtained mogrosides showed equivalent or more potent effects on the glucose uptake in HepG2 cells in vitro. These results suggested the mogrosides in the fruit of S. grosvenori were worthy of further research to confirm their potential benefits for obese and diabetic patients.