Study On Extraction,isolation,purification And Antioxidant Activity Of Active Componend From Lentinus Edodes

Lentinus edodes is a kind of medicinal and edible fungus.It plays an important role in antibacterial,antitumor,enhance immune activity function,which contains amino acid,vitamin,polysaccharide,mineral element and so on.It has high nutritional value and medicinal activity.It is a kind of health and functional food,which worth developing and utilizing.This study was based on the L.edodes fruiting bodies.Firstly,the optimal process conditions for extracting L.edodes polysaccharides were obtained by optimizing traditional hot water extraction process based on response surface design.The crude polysaccharide of L.edodes was extracted by the hot water extraction,ultrasonic assisted extraction,enzyme extraction and microwave assisted extraction,respectively.And compared and analyzed the sugar content,protein content,monosaccharide composition and structure characteristics.The best extraction method was microwave aided the traditional hot water extraction.Based on the single-factor test results,the retention rate of polysaccharides and decolorization rate of H₂O₂,chitosan and activated carbon were compared by orthogonal method.The polysaccharide retention rate and protein removal rate were compared by orthogonal method.In general,activated carbon method is the optimal decolorization method,and hydrochloric acid method is the optimal decolorization method.The optimal method was used to decolor and deproteinate the polysaccharide,and then alcohol precipitation,test the antioxidant activity,select the optimal active part.The technological conditions of extracting mushroom ethanol extracts were optimized by the response surface method,and the author compared the biological activities of different polar parts with each other.The main methods and results in this study were as follows:The optimal technical conditions of hot water extraction have been determined and they are as follows:solid-liquid ratio1:41.39?g/ml?,2.60 h,92.86?.The actual extraction rate is 4.91%,model predictive value is 5.03%,and error is 2.38%.The results showed that the model fit well and the extraction conditions of L.edodes polysaccharides were optimized effectively.L.edodes polysaccharides were extracted by four methods,and the author compared and analyzed the sugar content,protein content,monosaccharide composition and structure characteristics.The polysaccharide prepared by microwave assisted extraction had the highest extraction rate 9.48%and highest purity 43.17%.The extraction rate and sugar content of polysaccharides by hot water extraction were only 4.76%and 18.13%.The sugar content was significantly higher than that of hot water extraction,and the polysaccharides obtained by microwave assisted method had strong antioxidant activity.Considering comprehensively,the author believed that microwave assisted extraction was an ideal method to extract polysaccharide from L.edodes.The decolorization rate of activated carbon was 70.24%and the retention rate of polysaccharides was 73.15%.Compared with undecolorized water extract polysaccharides,the activated carbon had higher decolorization rate and polysaccharide retention rate.Considering comprehensively,the activated carbon method was the optimal decolorization method.The protein removal rate of hydrochloric,trichloroaletic acid method,and sevage method were 70.61%,34.92%and 56.89%,respectively.The polysaccharide retention rate of hydrochloric,trichloroaletic acid method,and sevage method were respectively 50.39%,63.69%,57.71%.The colligation score of hydrochloric,trichloroaletic acid method,and sevage method were respectively 60.50,49.31,57.30.The hydrochloric acid method had high protein removal rate and polysaccharide retention rate.Compared with crude polysaccharides,the DPPH free radical scavenging capacity and hydroxyl radical scavenging capacity of polysaccharides after hydrochloric acid deproteination were significantly enhanced.So the hydrochloric acid method was selected to removal protein.It was found that the antioxidant activity was positively correlated with the sugar content,and the higher sugar content had the stronger activity.The content of polysaccharide was LEP₆₀?72.33%?>LEP₈₀?40.60%?>LEP₃₀?38.51%?,the DPPH free radical scavenging power was LEP₆₀>LEP₈₀>LEP_30,the hydroxyl free radical scavenging power was LEP₃₀>LEP₈₀>LEP_60,and the total reducing power was LEP₆₀>LEP₃₀>LEP₈₀.Considering comprehensively,LEP₆₀0 is the part with strong antioxidant activity in L.edodes polysaccharide,which is worthy of further research and development.The optimal technical conditions of ethanol extracts extraction had been determined:the extraction temperature was 40?,the extraction time was 2.23 h,the solid-liquid was1:9?g/mL?,and the alcohol concentration is 51.50%.The yield of ethanol extract was16.79%,the predictive value was 17.54%,and error value was 4.27%.In general,4kinds of extracts exhibited increasing antioxidant activity with increasing concentration at the ranges of tested dosage,and is close to the activity of ascorbic acid and lentinan polysaccharides.The extraction rate of alcohol extrac was 16.79%,apparently higher than the extraction rate of L.edodes polysaccharides,which can provide some references for the actual production.