Systematic review of the digestive fate of rice phenolic compounds: Insights into bioavailability, influencing factors, encapsulation strategies, and health implications

Abstract

Background

Rice is a staple food for billions worldwide and a rich source of health-promoting phenolic compounds. The availability of phenolic compounds is a critical determinant of their capacity to confer health benefits.

Scope and approach

This study encompasses a systematic review of extant research on the bioaccessibility and bioavailability of rice phenolic compounds, shedding light on approaches to augment phenolic bioaccessibility. This article delves into the potential health benefits of these compounds and identifies current knowledge gaps and future research directions. Following the PRISMA 2020guidelines, a thorough literature search was conducted across the Scopus, ScienceDirect, and Web of Science databases, encompassing the Science Citation Index Expanded (SCIE) and English-language publications spanning approximately 10 years up to February 2, 2024. A thorough analysis of 70 eligible reports was conducted to explore the relationship between rice phenolic compounds and digestive processes.

Key findings and conclusions

The examined literature indicates that rice phenolic compounds transform during digestion and colonic fermentation to lower-molecular-weight phenolics. Various factors, including rice variety and origin, particle size, phenolic structure, gut microbiota, food matrix, and rice processing techniques, influence phenolic bioaccessibility and bioavailability. Encapsulation strategies enhanced the digestive stability of anthocyanins and flavonoids, while the phenolic profile, physicochemical properties, and water solubility of the wall materials influenced their release. Digestion unlocked the biological activities of rice phenolics, including antioxidant, anti-inflammatory, anticancer, antihyperlipidaemic, antihypertensive, antidiabetic, and gut-maintaining properties. These insights will pave the way for the development of functional foods to optimize the health benefits of bioactive compounds.