Extraction, Isolation and in Vitro Immunological Activity of Polysaccharides from Wine Made from Glutinous Rice and Chinese Chestnut

Polysaccharides (CWP) from nutritious wine made from glutinous rice with added Chinese chestnut as a nutritional fortifier using the traditional fermentation process of Chinese rice wine (Huangjiu) were obtained by fractional ethanol precipitation and purified by ultrafiltration into two fractions: CWP-1 (> 100 ku) and CWP-2 (30–100 ku). CWP-1 and CWP-2 were mainly composed of eight monosaccharides, including galactose, mannose, glucose, arabinose, xylose, fucose, galacturonic acid and glucuronic acid. Infrared spectroscopy analysis showed the typical absorption peaks of both polysaccharides and the presence of α- and β-glycosidic bond conformations in CWP-1. In vitro immunological assays showed that CWP-1 and CWP-2 significantly induced the secretion of tumor necrosis factor-α (TNF-α), interleukin 6(IL-6) and nitric oxide (NO) by mouse macrophages RAW 264.7, and their capacity to secrete cytokines was higher than that of lipopolysaccharide (LPS) at the same mass concentration. This study will provide theoretical references for the research and utilization of functional components in chestnut processed Chinese chestnut products and new Huangjiu.