Extraction process, structural characterization, and digestive properties of type 3 resistant starch from Angelica Dahurica, and its impact on gut health in obese mice.

This study investigated the anti-obesity effects of type 3 resistant starch from Angelica dahurica (Ad-RS3) based on intestinal health. Response surface methodology was employed to optimize the extraction rate of Angelica dahurica starch (AS). The structural and digestive properties of AS and Ad-RS3 were then compared. Additionally, the anti-obesity activity of Ad-RS3 was investigated by constructing an obese mouse model. The results showed that the extraction rate of AS increased to 44.72 % under optimal conditions. Compared to AS, Ad-RS3 exhibited a higher degree of order (2.684), crystallinity (55.94 %), gelatinization temperature (72-74 °C), and particle size range (0.564-563.7 μm). The high level of resistant starch (82.16 %) was maintained after Ad-RS3 was digested in vitro through the oral-stomach-small intestine, then fermented in the colon. This process significantly increased the levels of Acetic, Propionic, and Butyric acids, as well as the abundance of beneficial bacteria (Muribaculum and Dubosiella). It also reduced the Firmicutes/Bacteroidetes ratio, effectively reducing body weight and improving obesity-related dyslipidemia and liver damage. These results suggest that Ad-RS3 can be used as a holistic, food-based strategy to promote gut health and prevent obesity.