Identification And Influencing Factors Of Characteristic Compounds In Morchella Sp. Based On Metabolomics

Morchella,known as a kind of wild edible and medical mushroom worldwidely,has been successfully cultivated in China since 2011.However,the unique natural compositions contributing to Morchella’s bioactivities are rarely reported.The characterization of Morchella,producing by wild-collected and artificial-cultivated,has not yet been clear until now.Besides,there is no study about the relatively overall influences of biochemical compositions by varieties and environment qualities to our knowledge.Therefore,non-targeted metabolimics coupled to molecular networking approaches were developed for the analysis of characteristic compositions in Morchella in the present study.The characterization influenced by growth pattern,varieties and environment qualities were also studied based on the widely targeted metabolomics combined with multiple factor analysis.The study was designed to provide preliminary data for Morchella production and consumption.The main contents and results were as follows:Firstly,an untargeted metabolomics approach based on UPLC-Q-TOF-MS combined with multivariate statistical analysis were employed for screening unique natural products in wild Morchella.The results indicated that Morchella was enriched in fatty acids,especially polyunsaturated fatty acids.Moreover,four peptides,including desferriferricrocin,desferriferrichrome,desferriferrichrome C,and a newly annotated homolog MP-2 were identified based on molecular networking analysis.To the best of our knowledge,this is the first report of four peptides,belonging to hydroxamate siderophore peptides,were identified in Morchella.Furthermore,MP-2 were isolated and purified from M.elata Fr.fruitingbody,then identified by NMR and compared to Scifinder database,proved to be a newly compound.Meanwhile,another new homolog was also purified and identified,namely MP-1.The five hydroxamic-acid-structure cyclopeptides can significantly inhibit the number of Caco-2/Hep G2 cells proliferation.Secondly,the compositional differences of Morchella between wild-collected and artificial-cultivated were analysed by UPLC-Q-TOF-MS.Results indicated that hydroxamatesiderophore peptides and lipids were two major kinds of characteristic compounds.The new identified MP-2 which was abundant in wild Morchella could be used as a biomarker for the distinction with cultivated Morchella.PUFAs were enriched in wild Morchella,whereas LPCs were abundant in cultivated samples.In addition,flavor amino acids were rich in wild Morchella,but taste active values of bitter amino acids were higher in cultivated Morchella.Thirdly,the characteristic components influenced by varieties(M.importuna and M.sextelata)were investigated by widely targeted metabolomic analysis.The samples were obtained by field experiments.M.importuna was abundant in lipids,carbohydrates and their derivants.The feature taste compounds of Morchella,including γ-aminobutyric acid(GABA),D-(+)-galactose and malic acid,were all higher in M.importuna.Desferriferrichrocin and γ-glutamyl peptides with biological activities were also enriched in M.importuna.However,nucleosides were more abundant in M.sextelata,such as guanine,vernine,inosine.These results would provide a theoretical basis for the breed of varity.Fourthly,the characteristic components influenced by environment conditions were also studied by widely targeted metabolomic analysis.The samples were acquired by field experiments from six firms in six provinces.Results showed that four kinds of metabolisms were more affected,including amino acids,organic acids,nucleosides and saccharides(alcohols),especially amino acids.Lipids,also a kind of characterization in Morchella,only had a notablely negative correlation with altitude.Five environmental factors,including temperature,latitude,altitude,longitude and organic matter content,had greater influence for the accumulation of metabolites of Morchella.The feature of high altitude and low latitude in Yunnan was beneficial to the accumulation of metabolites,especially amino acids and their derivants,whereas the super-high altitude in Qinghai leaded to down-regulated of metabolites,excepting for a few varieties of nucleosides and amino acids.These results would provide essential information for regional brand building,and also give a new idea for the improvement of cultivated techniques.