Alkaline Extracted Purified Polysaccharide from Hulless Barley Grass and Its Proliferation Inhibitory Effect Against Cancer Cells

Hulless barley (HB) grass is a potential resource of functional food. In this study, the proliferation inhibitory effect against cancer cells of an alkaline extracted polysaccharide (APP) from HB grass (HBG) is analyzed. The yield of crude alkaline extracted polysaccharide (APC) reaches 15.1%. After purification, the purity and polydispersity index (PDI) of the APP are 98.3% and 1.38, respectively. The molecular weight of APP is 5.1 × 10 5 Da, whereas the number-average molecular weight of APP is 3.7 × 10 5 Da. APP is composed of arabinose (37.8%), xylose (41.3%), glucose (4.6%), and galactose (16.3%). According to the infrared spectral analysis, APP is found to contain β-glycosidic bonds. Moreover, APP possesses significant cell proliferation inhibitory effects against various cancer cell lines, such as 4T1, HT29, Caco-2, and CT26.WT in a dose-dependent manner. Notably, the IC50 value of 4T1 reaches 7.56 mg mL −1 , which indicates that APP from HBG has a potential anti-cancer effect in vitro. It may be further investigated as an ingredient or nutraceutical for development and utilization in functional foods to prevent or treat cancer and related diseases.