Development of alginate/inulin-based Oral Superabsorbent Hydrogel carrier systems for delivery of white hyacinth bean polysaccharide: Improvement of characteristics and weight management in diet-induced obese mice

White hyacinth bean polysaccharide (WHBP) was demonstrated to be effective in weight control and hypolipidemic regulation. Oral Superabsorbent Hydrogels (OSH), a class of dietary hydrogels capable of absorbing large amounts of water in the gastrointestinal tract, have emerged as an innovative carrier system for treating obesity. Here, combination of sodium alginate and inulin was employed to prepare OSH containing WHBP (named WHBP-OSH). Inulin was selected to improve characteristics of WHBP-OSH, and 5 concentrations of inulin (0–20 %) were tested in this work. Results showed that 10 % inulin was optimal for achieving superior encapsulation efficiency, mechanical properties and swelling capacity. Moreover, digestive behaviors suggested that WHBP-OSH presented significant water absorption and swelling, in addition to stability in both stomach and small intestine regions, thereby achieving colon-targeted delivery of WHBP. Subsequently, a 17-week high-fat diet-induced obesity mouse model was used to address roles of WHBP-OSH in obesity, and results showed that WHBP-OSH resulted in higher levels on weight reduction, Lees index, Body Mass Index (BMI) and adipose index than did OSH alone in obese mice, indicating that WHBP enhanced the anti-obesity effects of OSH. Mechanically, anti-obesity effects of WHBP-OSH were associated with decreasing eating behavior by suppressing the appetite reward and motivation aspects of obese mice. Together, WHBP-OSH containing 10 % inulin could develop a promising colon-targeted OSH, and showed significant potential as a weight management strategy via reducing eating behavior.