Honeysuckle macroflorum is a medicinal and edible homologous plant in southwest China. Its polysaccharide has various biological activities, but there are few researches on its polysaccharide, and the extraction methods have significant effects on the yield, structure and biological activities of polysaccharide.
Samples of Honeysuckle were collected from Suiyang, Guizhou Province, using analytical chemical reagents and distilled water.
Ultrasonic-assisted extraction and complex enzyme extraction were used to investigate the effects of each factor on polysaccharide yield of Lonicera macroflorum. On this basis, the response surface method was used to optimize the extraction process and determine the best extraction conditions.
There were differences in the chemical composition, monosaccharide composition, molecular weight, structure and microscopic morphology of polysaccharide extracted by the two methods. Ultrasonic-assisted extraction of Honeysuckle polysaccharide showed smaller particle size, more negative zeta potential, stronger water and oil holding capacity, and crystalline structure. Polysaccharide from Lonicera macroflorum extracted by compound enzyme had higher content of uronic acid, micromorphology was porous and in the form of amorphous polymer.
Ultrasound-assisted extraction of Lonicera macrophylla polysaccharide was superior to compound enzyme extraction of Lonicera macrophylla polysaccharide in antioxidant, lipid-lowering, nitrite scavenging and antitumor activities. In the antioxidant experiment, the ultrasonic assisted extraction of honeysuckle polysaccharide had higher scavenging rate of various free radicals. In the experiment of lowering blood lipid, the inhibition rate of porcine pancreatic lipase and the ability of cholic acid binding were stronger. In the nitrite removal experiment, ultrasound-assisted extraction of honeysuckle polysaccharide had better clearance rate and blocking nitrosamine synthesis. In the anti-tumor experiment, the sonic-assisted extraction of Honeysuckle polysaccharide had more significant inhibitory effect on the proliferation of various tumor cells.
Both ultrasound-assisted extraction and complex enzyme extraction can effectively extract polysaccharide from Lonicera macrofloris. The yield of complex enzyme extraction is slightly higher, but the polysaccharide extracted from Honeysuckle Macrofloris by ultrasonic-assisted extraction has better biological activity and more stable structure.
