The Modification Of Poria Cocos Polysaccharide And Its Antioxidant Activity Evaluation In Vitro

Poria cocos is a kind of medicinal and edible fungus, its main ingredient is β-pachyman, accounts for about 93% of the dry poria cocos. Studies have shown that β-pachyman are a kind of β-(1→3)-D-glucan with a little (1→6)-β-glucan branched chain, which is a tight molecular structure, poorly water-soluble, low biological activity. The key way to exploit and utilize Poria coco-s and pachymose efficiently is to adopt a structure of carboxymethylated modi-fication technology and a new polysaccharide degradation technology, which make pachyman convert to polysaccharides with higher activity and bioavailabi-lity.In this paper, in order to get water soluble pachyman(WSP), carboxymeth-ylated modification and xylanase were used to assisted degrade pachman after irradiation to get a more safety, environmental protection and energy saving of poria cocos polysaccharide modification technique. And on the basis of ori-ginal carboxymethylated modification process in the laboratory, considering the influence factors of viscosity, further optimize the process, in order to obtain high substitution degree, low viscosity of carboxymethyl polysaccharide, and d-esign a simple flow chart of industrialized production device, in order to suita-ble for large-scale industrial production. The main results were as follows:1. On the basis of the original test results in the laboratory, further consid-ering the infuence factors of viscosity, with carboxymethylated polysaccharide substitution degree and viscosity as evaluation index, optimizing the powder pr-ocessing technology of carboxymethylated modification, the optimal carboxym-ethylated modification process conditions was as follows:Swelling when added to the amount of ethanol and raw material ratio of 7:1, swelling of 85%eth-anol concentration, stirring speed of 15 r/min (swelling fluid volume was 70 mL), quaternization reaction temperature 50℃, etherification temperature 60℃, washing 4 times (intense mixing glass rod 20 min), carboxymethyl can be obt-ained under the condition of poria cocos polysaccharide substitution degree is 0.6960, viscosity of 1.168 mPa-S.2. Soluble sugar content in the raw powder 1.3%, soluble sugar content is 5.95% after 27kGy irradiation; After xylanase solution of soluble sugar content of up to 9.23%; In the enzyme solution again after the irradiation of tuckah-oe powder soluble sugar content is 16.93%; Irradiation again after the enzyma-tic hydrolysis of the soluble sugar content in poria cocos powders is 38.84%. The optimum process conditions of xylanase solution for:enzymatic reaction temperature 50℃, pH5.5, enzymatic reaction time of 120 min, enzyme dosage 5.0%.3. Irradiation assisted carboxy methylation modification, irradiation dose for 27 kGy tuckahoe powder, compared with that without irradiation tuckahoe powder in the solubility modification product fairly and other reaction conditio-ns under the condition of same, shorten the reaction time of 3.5 h.4. Infrared spectrum analysis found that:tuckahoe polysaccharide has the general polysaccharide material in infrared spectrogram characteristic structure, types and methods of the glycosidic bond for beta-glycosidic bond; Poria cocos by carbonyl compounds generated after irradiation treatment, irradiation can make tuckahoe polysaccharide is degraded, its molecular weight decreased; Carboxymethylated modification of poria cocos polysaccharide in the N and (or) O a different degree of carboxymethyl is introduced, and the irradiation tr eatment can make carboxymethyl instead of the more obvious.5. After different treatment of poria cocos in vitro antioxidant capacity re-sults show that the water extract of poria cocos after chemical modification, physical degradation and enzymatic hydrolysis, the water extract of poria cocos composite antioxidant ability enhanced, the poria cocos after irradiation, carbo-xymethylated treatment, the water extract of antioxidant activity was significan-tly better than the untreated and after enzymolysis processing poria cocos anti-oxidant activity of water extract.