Comparative Study of the Effectiveness of Cellulose, Pectin and Citrus Peel Powder in Alleviating Loperamide-Induced Constipation

Constipation is a global health issue, with a prevalence of approximately 16%, and insufficient dietary fiber intake is a major contributing factor. Citrus peel residue contains a high proportion of dietary fiber, accounting for about 20–44% of its composition. In this study, the constipation-relieving effects of three functional components derived from citrus peel residue—cellulose (CEL), pectin (PEC), and citrus peel powder (CPP)—were systematically compared using a loperamide-induced mouse model. All groups were administered an equivalent dose of 200 mg/kg daily. The results showed that supplementation with CEL, PEC, and CPP improved defecation parameters. Among these, PEC effectively modulated the SCF/C-kit and Nrf2/HO-1 pathways. Compared with the model group, PEC increased Akkermansia abundance by approximately 34% and reduced Desulfovibrio abundance by about 26% Additionally, the smaller particle size and improved solubility of PEC promote the production of beneficial metabolites, thereby alleviating constipation. In contrast, CEL primarily alleviates constipation through its physical properties. At equivalent doses, CPP provides less constipation relief due to its lower component concentrations and a primary composition of insoluble dietary fiber. These findings provide preliminary mechanistic insights and support further exploration of citrus by-products as functional food candidates for the management of constipation.