A review on the gastrointestinal protective effects of tropical fruit polyphenols

AbstractTropical fruits are popular because of their unique, delicious flavors and good nutritional value. Polyphenols are considered to be the main bioactive ingredients in tropical fruits, and these exert a series of beneficial effects on the human gastrointestinal tract that can enhance intestinal health and prevent intestinal diseases. Moreover, they are distinct from the polyphenols in fruits grown in other geographical zones. Thus, the comprehensive effects of polyphenols in tropical fruits on gut health warrant in-depth review. This article reviews, first, the biological characteristics of several representative tropical fruits, including mango, avocado, noni, cashew apple, passion fruit and lychee; second, the types and content of the main polyphenols in these tropical fruits; third, the effects of each of these fruit polyphenols on gastrointestinal health; and, fourth, the protective mechanism of polyphenols. Polyphenols and their metabolites play a crucial role in the regulation of the gut microbiota, increasing intestinal barrier function, reducing oxidative stress, inhibiting the secretion of inflammatory factors and regulating immune function. Thus, review highlights the value of tropical fruits, highlighting their significance for future research on their applications as functional foods that are oriented to gastrointestinal protection.Keywords: Tropical fruitspolyphenolsgut healthmicrobiotainflammatory bowel diseasesfunctional foods Disclosure statementThe authors have no conflicts of interest to declare.CRediT authorship contribution statementQianer Jiang: Writing-original draft preparation. Suvimol Charoensiddhi: Writing - reviewing & editing. Xiaofeng Xue: Conceptualization, Supervision. Biqi Sun: Writing - original draft preparation. Yang Liu: Supervision, Reviewing and Editing. Hesham R. El-Seedi: Supervision, Reviewing and Editing. Kai Wang: Conceptualization, Methodology, Writing - original draft preparation.Additional informationFundingThis work was supported by the National Natural Science Foundation of China under Grant (No. 31702287). We also acknowledge the financial support from Beijing Nova Program and the Youth Innovation Program of the Chinese Academy of Agricultural Sciences (Grant No. Y2022QC09).