Induction grass polysaccharide with activity and preparation method thereof

The invention discloses induction grass polysaccharide with alpha-glucosidase inhibitory activity and antioxidant activity, monosaccharide of the induction grass polysaccharide comprises xylose, galactose, mannose, glucose and rhamnose, and the molar ratio of the monosaccharides is 1.00: 0.03: 2.00: 1.11: 0.19; the method comprises the following steps: crushing induction grass, extracting induction grass powder for multiple times by using water as an extracting agent at 75-100 DEG C, combining extracting solutions, and concentrating to obtain a concentrated solution; refining the concentrated solution by adopting alcohol precipitation and a deproteinization reagent to obtain the induction grass polysaccharide; the operation method is simple, the induction grass polysaccharide with high alpha-glucosidase inhibitory activity and excellent oxidation resistance is creatively extracted from induction grass plants, the variety of alpha-glucosidase inhibitors and antioxidants extracted from plants is enriched, and t