Cleaning Process of Diosgenin from Dioscorea nipponica

This investigation employed HPLC and LC-MS techniques to elucidate the enzymolysis and acid hydrolysis mechanisms of diosgenin obtained through a cleaning process. The findings revealed that the enzymolysis led to the cleavage and subsequent recombination of the glycosidic bond at the C-26 position of protodioscin, resulting in the formation of dioscin present in the enzymatic hydrolysis filter residue. Leveraging this observation, a streamlined and eco-friendly method for diosgenin extraction was devised. Incorporating the Box-Behnken response surface methodology alongside wastewater assessment, the optimal parameters for the cleaning process were established: a sulfuric acid concentration of 3 mol · L−1, a solid–liquid ratio of 1:10, an acid hydrolysis temperature of 100 °C, and an acid hydrolysis duration of 3 h. Under these parameters, the yield and purity of diosgenin were 31.07±0.56% and 72.30±0.24% respectively. When benchmarked against the direct acid hydrolysis approach, there was an increase of 133.08% in diosgenin yield, 44.08% enhancement in diosgenin purity, 50% reduction in wastewater generation and acid utilization, and an 83.57% decrease in wastewater’s chemical oxygen demand (COD). This optimized cleaning process is viable for large-scale production and offers a sustainable method for diosgenin production.