Palliative Effects of Phenolic, Polysaccharide, and Lipid Extracts of Hulless Barley Grass on Acute Ulcerative...

Hulless barley grass (HBG) is rich in bioactive compounds such as phenolics, polysaccharides, and lipids, and consequently possesses antioxidant, anti-inflammatory, and anti-tumor properties. However, which components contribute to its potential palliative effect on acute ulcerative colitis (AUC) is unknown. In this study, phenolics, polysaccharides, and lipids were extracted separately from HBG, and their antioxidant activities and effects on AUC in vivo were investigated. Compared to the polysaccharide/lipid extracts, phenolic extracts (HBGPE) had much higher antioxidant capacity, with 1,1-diphenyl-2-picrylhydrazyl radical (DPPH·) scavenging capacity of 1.34 ± 0.02 mmol Trolox/100 g. The HBGPE also significantly decreased the body weight loss and colonic condition of dextran sodium sulfate (DSS)-induced AUC mice. The strong anti-inflammatory effects of HBGPE led to a significant reduction in the degree of inflammatory cell infiltration, crypt structure disruption, and mucosal damage, and down-regulated the mRNA expression of tumor necrosis factor (Tnfα), interleukin-6 (Il6), and Il1b. In addition, HBGPE could reduce intestinal flora disorders. Both polysaccharide and lipid extracts led to little reduction in the colon inflammatory condition. This study confirmed that HBG extracts could inhibit inflammatory response, oxidative stress, and gut microbial imbalance, especially HBGPE, which indicated that HBG may have potential for application in dietary prevention of AUC.