Highly Esterified Starch Citrate Synthesized via Sequential Extrusion and Thermal Curing Attenuates Carbohydrate-Driven Adiposity and Dyslipidemia in Mice

Resistant starch (RS), which is resistant to upper gastrointestinal digestion with minimal postprandial glycemic impact, serves as an effective nutritional strategy for mitigating diet-induced obesity and associated metabolic dysfunctions. In this study, starch citrate with a degree of substitution (0.087) and high RS content (83.7%) was synthesized via sequential reactive extrusion and dry-heat treatment, and its anti-obesity efficacy was evaluated in C57BL/6NCrljOri mice fed a gelatinized high-starch diet (HSD). Mice fed the gelatinized HSD exhibited significant increases in body weight and visceral adiposity alongside impaired glucose tolerance, demonstrating an obesogenic phenotype under the present dietary conditions. Dietary supplementation with starch citrate dose-dependently attenuated excess fat accumulation, suppressed epididymal adipocyte hypertrophy, and preserved systemic glucose homeostasis. Furthermore, starch citrate modulated circulating adipokine levels and improved selected serum lipid profiles, while complete starch citrate substitution significantly downregulated hepatic protein expression associated with de novo lipogenesis and adipogenic transcriptional regulation. Consequently, starch citrate demonstrates significant preventive potential against diet-induced obesity and associated metabolic complications, including dyslipidemia and impaired glucose homeostasis. Overall, these findings suggest that starch citrate may serve as an RS-rich eco-friendly functional food ingredient with the potential to attenuate metabolic dysfunctions and obesity triggered by the consumption of rapidly digestible carbohydrates.