Recent insights into the physicochemical properties, bioactivities and their relationship of tea polysaccharides

•Unknown of advanced structure limits the study of TPS structure–activity relationship.•The formation of TPS conjugates limits the understanding of physicochemical property.•Most publications believed that TPS exert effects by regulating the gut microbiota.•TPS with good performance in bioactivity often have some similarity in primary structure. Tea polysaccharides (TPS) is receiving global concern in past years due to their therapeutic effects in many diseases such as obesity and diabetes. Many publications imply that the unique physicochemical properties and bioactivities of TPS are prerequisites for its use as a biofilm, drug carrier and emulsifier. Despite numerous healthy benefits, studies on the in-deep structure–activity relationship of TPS still not well explored and explained yet. The main reasons for the research limitation are attributed mainly to the unbreakable advanced structural research technology and the formation of TPS conjugates. The present review also summarizes some similar parameters in primary structure of TPS with better bioactivities, discusses the relationships between their physicochemical properties and bioactivities, and suggests that function-specific TPS would be obtained in the future if the links between preparation methods, physicochemical properties and bioactivities of TPS could be well understood and established.