Ultrasound-enzyme-assisted extraction of flavonoids, polysaccharides, and triterpenes from Gualou and Xiebai: optimization, bioactivity, in vitro digestive stability, and impact on lipid digestion.

Gualou (Trichosanthes kirilowii Maxim) and Xiebai (Allium macrostemon Bunge) have been extensively studied for their diverse active ingredients, which include flavonoids, polysaccharides, and triterpenoids. This study employed a single-factor experiment alongside the Plackett-Burman design and utilized response surface methodology to optimize the ultrasonic-enzyme-assisted extraction (U-EAT) method for the functional components in Gualou and Xiebai (GLXB). The optimal extraction conditions were identified as a solid-to-liquid ratio of 1:11 g/mL, an alcohol concentration of 55%, an enzyme concentration of 1.