| This paper systematically studied that extraction, separation, purification and molecule modification (sulfated esterification and carboxymethyl ether and metal ion chelate) of polysaccharide from the leave in Hippohae rhamnoides L.. We studied the antioxidant and bacteriostatic functions on the polysaccharide and molecule modified polysaccharide from the leave in Hippohae rhamnoides L., which established a basis for them in foodstuffs, medicine and health supplies, etc. The main contents are as follows:(1) We made some studies on the extraction process of polysaccharide from the leave in Hippohae rhamnoides L.. In order to study the extract technology of polysaccharide from the leave in Hippohae rhamnoides L., this article used yield as the criterion and compared the follows 3 extraction methods:aqueous extract, microwave-assisted and supersonic-assisted and through response surface analysis on ultrasonic method optimized the best conditions:when the liquid-solid ratio of 52.5:1, ultrasonic power of 607.1 W, ultrasonic time of 42.3min, the polysaccharide yield was maximum with estimated value was 7.74%, and verified value was 7.68%.(2) The best method for deproteinization of polysaccharides from the leave in Hippohae rhamnoides L. was Sevag, which composed with chloroform and butanol (V/V=4:1). After six times deproteinization of polysaccharides, the clearance ratio of protein was 78.96%, then the loss ratio of polysaccharides was only 33.75%. In addition through acute toxicology test, it proved that the polysaccharide from the leave in Hippohae rhamnoides L. are non-toxic lever in actually and the LD50>15000mg-kg-1-bw-1, MTD>30000mg-kg-1·bw-1-d-1.(3) Via removing protein, decolor and removing small molecules, the polysaccharides from the leave in Hippohae rhamnoides L. were convert into three ingredients (SJ-1, SJ-2 and SJ-3) by DEAE-cellulose. Analyzed by the tests of ultraviolet spectroscopy and freezing-thawing, we found that the contents are 11.64%,77.67% and 10.69% in each. In further, we used the technology of gas chromatography to test the contents of the polysaccharides (SJ-2), and we foud that it was comprised of 15.18% of Rhamnose,13.22% of Arabinose,20.38% of Mannose,33.03% of Glucose and18.19% of Galactose.(4) The polysaccharide from the leave in Hippohae rhamnoides L. had certain degree antioxidant capacities in vitro, (Scavenging ability of hydroxyl radical and superoxide anion, Total antioxidant activity). When the concentration of polysaccharide was 1200μg-mL-1, the removal effect towards superoxide anion was of higher than Vc by 18.92%.(5) The optimum sulfated esterifing technics was determined:the volume ratio of chlorosulfonic acid and pyridine was 3:1, esterifing temperature was 60℃, and esterifing reaction time was 2.5h. Under this condition, the substituted ratio of polysaccharide was 0.51. Infrared spectrometry spectra showed that sulfated compounds may be formed sulfate and SJ-2.(6) The optimum etherified technics was determined:the concentration of isopropyl alcohol was 80%, the molare ratio of sodium hydroxide and monochloroacetic acid was 2.5:1, etherification time was 3h, and etherification temperature was 50℃. Under this condition, the substituted ratio of carboxymethyl was 0.73.(7) The optimum chelated technics was determined:the volume ratio of polysaccharide and zinc ion was 5:1, the initial concentration of zinc ion was 6mg/mL, and chelating reaction time was 8h. Under this condition, the chelated volume ratio of polysaccharide was 73.89%.(8) The results tested by the method of agar diffusion showed that the polysaccharide restrainted the growth of Escherichia coli, Bacillus subtilis and Staphylococcus aureus in some certain and the effects would be enhanced after molecular modification. Results showed that the chelated polysaccharide had the best effects towards the three bacterias and sulfated polysaccharide and etherified polysaccharide in next.
|
PDF Full Text Request