Potential of Herbal Leaf and Fruit Juices as Antidiarrheal Agents, Gut Dysbiosis Modulators, and Prebiotics: A Systematic Review

Background: Diarrhea and gut dysbiosis are closely related gastrointestinal disorders that remain major public health problems worldwide. Herbal-based therapies, particularly leaf and fruit juices, have long been used as complementary treatments. However, recent scientific evidence regarding their mechanisms and clinical relevance remains fragmented. Objective: This systematic review aimed to evaluate recent scientific evidence on the potential of herbal leaf and fruit juices as antidiarrheal agents, modulators of gut dysbiosis, and prebiotics, with a particular focus on Muntingia calabura (cherry tree) leaves and fruits. Methods: A systematic literature search was conducted in PubMed, Scopus, and Google Scholar following PRISMA 2020 guidelines. Studies published between 2021 and 2025 that investigated aqueous extracts or juices of herbal leaves and fruits in relation to diarrhea, gut dysbiosis, or prebiotic activity were included. In vitro, in vivo, food product development studies, and systematic reviews were eligible. Results: A total of 25 studies met the inclusion criteria. Herbal leaves, particularly Muntingia calabura and Psidium guajava leaves, demonstrated antidiarrheal potential through antibacterial, anti-inflammatory, antimotility, and antisecretory mechanisms. In contrast, herbal fruits such as Muntingia calabura fruit, green banana (Musa spp.), and pomegranate (Punica granatum) primarily modulated gut microbiota composition and enhanced short-chain fatty acid (SCFA) production, indicating prebiotic activity. Conclusion: Herbal leaf and fruit juices exhibit complementary roles in diarrhea management and gut health. Leaves appear more effective for acute antidiarrheal effects, while fruits support microbiota restoration and dysbiosis prevention. Further well-designed clinical trials are required to confirm their efficacy and safety in humans.