Abstract
Polysaccharides in the diet have been increasingly recognized as major modulators of gut microbiota and multifunctional ingredients in food systems. Despite extensive research on various polysaccharides regarding their prebiotic activities, a comprehensive approach towards an integration of structural characteristics, chemical modifications, mechanistic degradation pathways, and food processing effects is still limited. This review aims to compile existing knowledge regarding the molecular characteristics of polysaccharides, including their monosaccharide composition, glycosidic linkages, branching, and molecular weight, in relation to their utilization by gut microbiota, production of short-chain fatty acids, and associated metabolic effects in the human body. Furthermore, this review will focus on carbohydrate-active enzymes and cross-feeding effects that play a major role in determining the biological activities of polysaccharides. The effects of food processing and food systems on polysaccharide functionality and utilization will also be considered. Despite promising therapeutic and nutritional potential, existing inconsistencies in research methods and a lack of standardized approaches in studying mechanistic effects are major hurdles in developing novel food systems that are targeted towards modulating gut microbiota.