Investigation into the Glucose-Regulating Activity and Mechanisms of Siraitia grosvenorii Extracts and their Application in the Innovation of Functional Biscuits.

Siraitia grosvenorii (Swingle) C. Jeffrey, a plant belonging to the Cucurbitaceae family, is widely recognized as a food-medicine homologous species in southern China. In this study, bioactive compounds from S. grosvenorii were investigated, and their potential application in developing functional biscuits was explored. Five triterpenoids were isolated from the 70% ethanol extract: 11-oxomogroside V (1), mogroside VIB (2), 11-oxomogroside VI (3), mogroside V (4), and mogrol (5). Among these, mogroside V exhibited the strongest inhibitory effect on α-amylase, with an IC₅₀ value of 0.44 ± 0.009 µM/L, indicating potent enzyme inhibition. Kinetic analyses revealed that compounds 1-5 acted as complex inhibitors of porcine pancreatic α-amylase, interacting with both the enzyme and the PPA-starch complex. Compound 1 functioned as a non-competitive inhibitor, while the others act competitively. Circular dichroism spectroscopy demonstrates that compound 4 induced the most pronounced alteration in the secondary structure of α-amylase, leading to enzyme inhibition. Furthermore, a functional biscuit incorporating S. grosvenorii extract was developed, and texture profile analysis showed that the extract had minimal impact on biscuit texture. These findings highlight the α-amylase inhibitory potential of S. grosvenorii and its promise as a natural sweetener and functional ingredient for improving the nutritional value of baked products.