Structure-activity relationship of barley leaf polysaccharides: Linking extraction methods to antioxidant efficacy and food additive potential

Abstract Barley leaf polysaccharides (BLPs) are key active components of medicine and food homology barley leaves. By comparing various extraction techniques, the relationship between BLPs and their antioxidant properties, as well as their potential functional characteristics were investigated. All BLPs were composed of the same seven monosaccharides and demonstrated excellent emulsifying and oil-holding abilities. Furthermore, antioxidant tests revealed that the fermented barley leaf polysaccharides (BLP-F) exhibited significantly superior efficacy in scavenging ABTS and hydroxyl radicals compared to the other two extraction methods, with scavenging rates of 99.95 ± 0.24% and 72.74 ± 2.90%, respectively. A strong correlation was also observed between antioxidant activity and uronic acid content, molecular weight, and monosaccharide composition. In conclusion, BLPs were distinguished by their unique composition, remarkable antioxidant and emulsifying capabilities, and their versatility as key ingredients in health supplements and food additives, providing a wide range of potential applications.