Research Of Selenium-enriched Yeast High-value Utilization

Selenomethionine in selenium-enriched yeast has the functions,such as slowing down the cancer progression,anti-oxidative and anti-inflammatory effects,and accelerating repair after spinal cord injury.In the cell wall of selenium-enriched yeast,the ?-glucan could enhance the immune response,cholesterol reduction,provide dietary supplements,controlf reshness,antifungal agents,and carry drug delivery.Mannan has effects on immune function and intestinal tract.This topic focuses on the extraction and modification of polysaccharides in cell walls and the method of separation selenomethionine.Extracting by using the enzymatic of ?-glucan from yeast,the purity is 84%,a yield is 11.00%,and the glucan is introduced carboxymethyl,phosphate and phosphate groups.Modified glucan can form a stable solution.The modified glucan is successfully introduced by FI-TR,NMR and SEM spectrum.The substitution degree of CMG is between 0.62 and 0.71,and the content of the substituted degree of PMG is 0.03,the content of the substituted degree of SMG is about 0.30.The substitution degree of CMG in pilot experiment is 0.88.Using the alkaline method to extract mannan,its yield is 4.81%.The effect of carboxymethyl modification on the degree of substitution in different conditions are studied and the results showe that the molar ratio of the reactants,that is,mannan:sodium hydroxide:Chloroacetate 1:2:2,is alkalized for 6 h.At a reaction temperature of 60? and a reaction time of 4 h,an optimal degree of substitution of 1.03 of carboxymethylmannan is obtained,and the characterization shows that the group is successfully bound.In the aspect of Se-Met separation method,the Se-Met content in the selenium-enriched yeast measured using LC-MS is 3.62 mg/g.After enzymatic hydrolysis of the yeast cells,the enzymatic solution is separated by 6kDa and 1KDa hollow fiber membrane and ultrafiltration cup.