Quality Evaluation And Chemical Composition Of Lentinula Edodes

Lentinula edodes（berk.）Pegler is the second largest mushroom in the world,second only to the Pleurotus.It is a kind of delicious food which is essential for people to eat.Through the literature review of mushroom,it is found that the majority of studies on polysaccharides and pharmacological activities of Lentinula edodes are mainly focused on the gas fingerprint of mushroom from different places,liquid fingerprint of polysaccharide extraction technology,SSR Analysis fingerprint of genetic diversity,capillary electrophoresis fingerprint of alkaloid components and SNP fingerprint of cultivated varieties However,there are few reports on the studies of the chemical components of the system and the fingerprint of different media mushroom.In this paper,the GC-MS fingerprint and ¹H-NMR fingerprint of 12 different substrates of Lentinula edodes were studied.The content of formaldehyde in Lentinula edodes was determined,and the chemical components were systematically separated and purified.The quality of Lentinula edodes was analyzed and evaluated from fingerprint,formaldehyde content and components.The GC-MS fingerprints of 12 kinds of Lentinula edodes with different substrates were established for the first time.The similarity between the new fingerprints and the control fingerprints was 77.5%～98.9%.After removing S8,the other 11 kinds of Lentinula edodes were established.The similarity between the new fingerprints and the control fingerprints was 93.1%～99%;The chemical structures of 26 of 30 common peaks were identified;The results of venny2.1.0 showed that there were 9 common components in 12 different substrates of Lentinula edodes,which were hexadecane,2-acetylpyrrole,acetic acid,pentadecane,tetradecane,2,2,4,4,6,8,8,10,10,12,12,14,14-tetradecylcycloheptasiloxane,benzaldehyde,ethylbenzene and n-tridecane;IBM SPSS statistics 26.0 software was used for cluster analysis of the samples,which could be roughly divided into three categories.The matrix S8 was a separate category,the Lentinula edodes of matrix S2,S3,S7 and S12 were classified into one category,and the other samples were roughly classified into one category.The cluster analysis results were consistent with the similarity evaluation results;IBM SPSS statistics 26.0software was used for principal component analysis of the samples.Four principal components were extracted,and the cumulative variance contribution rate was 91.31%.The comprehensive ranking of the samples showed that the Lentinula edodes Cultivated in substrates S5,S9 and S1 were in the top three,indicating that the Lentinula edodes Cultivated in these three substrates had higher content of common peak components and better quality than those cultivated in other substrates.The results showed that the substrate could affect the volatile components in Lentinula edodes,and the substrate of S8 had the lowest similarity because there was no bran added;The effect of corncob and sawdust in the substrate is similar.Hard sawdust can be used instead of sawdust.Adding lime can change the composition of cultivated Lentinula edodes and reduce the similarity.The results showed that the correlation coefficients of H1,H6-H8 and H10 were more than 95%,which indicated that adding at least 50%corncob could make the molecular structure of Lentinula edodes similar to that of adding lime;The results of cluster analysis showed that the samples were roughly divided into three groups.The content of corncob in H2-H5 matrix was less than 50%,and the other components were sawdust,gypsum and wheat bran;H1 and H12 belong to the same category,and the rest belong to the same category;IBM SPSS statistics 26.0 software was used for principal component analysis of the samples,and three principal components were extracted.The cumulative variance contribution rate was 94.548%,which indicated that 94.548%of the information content in Lentinula edodes GC-MS was determined by the three principal components.The comprehensive ranking of samples showed that the top three substrates were H12,H8 and H11,which were composed of sawdust/corncob/hardwood,wheat bran and gypsum respectively,indicating that the three substrates had similar effects.The formaldehyde content in dried and fresh Lentinus edodes was extracted and determined by acetylacetone method.The results showed that the formaldehyde content in dried Lentinus edodes(234.068 mg·kg^-1)was significantly higher than that in fresh Lentinus edodes(25.589 mg·kg^-1).The formaldehyde content in dried Lentinus edodes(25.589 mg·kg^-1)was significantly higher than that in fresh Lentinus edodes 733 mg·kg^-1)and formaldehyde content in mushroom residue(7.749 mg·kg^-1)decreased in turn.The results showed that formaldehyde could volatilize with water vapor,and the effect of open cooking was better.In this paper,silica gel column chromatography and Sephadex are used.The results showed that the five monomers were isolated from acetone extract of mushroom seed,petroleum ether extract of 75%ethanol extract and ethyl acetate extract by LH-20column chromatography,analysis and preparation HPLC.Five monomers were identified by combining physical and chemical properties with various spectral data(¹H NMR and ¹³C-NMR),ergosterol（1）,ergosterol 5α,8α-peroside（2）,mannitol（3）,uridine（4）and nicotinamide（5）.The above experimental methods are stable,simple and reliable.Comprehensive analysis can be used in the quality evaluation of Lentinula edodes and to identify the structural differences of different matrix mushrooms.