Structure and Biological Activities in Vitro Analysis of Polysaccharide from Coconut (Cocos nucifera L.) Haustorium

Coconut haustorium polysaccharide (CHP) was prepared by the method of water extraction and alcohol precipitation, its structural characteristics consist of monosaccharide composition, molecular weight size and distribution and infrared spectrum and biological activities in vitro such as antioxidant and hypoglycemic enzyme inhibiting activities were also analyzed. Results showed that CHP was an acidic heteropolysaccharide with the content of neutral sugar and uronic acid of 42.33% and 21.34%, which might contain pyran ring structure. Monosaccharide composition analysis indicated that CHP was mainly composed of fucose, rhamnose, arabinose, galactose, glucose, xylose and galacturonic acid and the molar ratio was 1.00:4.40:21.27:21.07:51.76:7.06:4.33. Molecular weight analysis showed that the CHP was composed of three components, of which peak 3 was the main component with the molecular weight of 1.53×10⁴ g/moL. Besides, DPPH and hydroxyl radical scavenging rate of CHP at 6 mg/mL were 82.49% and 85.83%, respectively. And its inhibition rate on α-glucosidase was 69.91% at 100 mg/mL. These research results could provide data support for the processing and utilization of coconut haustorium in functional food or medicine.