Influence Of Incubation Time On Metabolome Of Isaria Cicadae And Metabolomic Difference Between Isaria Cicadae And Cordyceps

To understand the metabolome difference between Cordyceps cicadae and it’s anamorph Isaria cicadae, their metabolome were determined by HPLC-MS, and the metabolomic differences were identified with multivariate analysis methods. The results will provide a theoretical basis for Cordyceps cicadae and Isaria cicadae development, utilization and quality control, meanwhile, it will provide scientific data for researches on chemical ecology of entomogenous fungi and relationship between fungi and insects. At the same time, metabolomic difference between mycelia of different incubation time were also analysed, the results will provide theoretical basis for fermentatin time selection and processing optimization. The studies can also help us to reveal metabolism of Isaria cicadae which can be theoretical basis for metaboltes regulation and products quality control.1 Metabolome differences between Cordyceps cicadae and it’s anamorph Isaria cicadaeCordyceps cicadae is a traditional Chinese medicine. It’s anamorph Isaria cicadae has multiple pharmacological activities which has been authenticated by modern pharmacological studies, however their metabolome differences are not report yet. In this study we use metabolomic method to study metabolome difference between Cordyceps cicadae and it’s anamorph Isaria cicadae. Principal Components Analysis(PCA) demonstrate that metabolomic difference between wild fruiting body(WFB) and wild insect body(WIB), between artificial fruiting body(AFB) and artificial insect body(AIB) are significant. At the same time, there is also ralative significant difference between wild and artificial samples, Fermented mycelia(FMY) have a great difference, and there is great difference between wild Cordyceps cicadae and artificial Cordyceps cicadae, however, There is less differerce between FMY and WFB or AFB than that between WIB and AIB. We use Orthogonal Projection on Latent Structure-Discriminant Analysis(OPLS-DA) to identify metabolome differences. Hierarchical Clustering Analysis(HCA) indicate that chang of growth conditions can srsult in metabolites change which may be caused through some gene expression upward or downward, result in. Metabolic pathways analysis revealed that different growth conditions can cause changes of many metabolic pathways, such as Purine metabolism, Nicotinamide metabolism, Beauvericin synthesis, Sphingolipid metabolism, Fatty acid metabolism, Amino acid and mannose metabolism and so on. WFB, WIB, AIB containe higher concentration of enniatin B, enniatin B4, beauvericin, beauvericin E, beauvericin G2, beauvericin D, beauvericin B, lateritin, streptimidone, anisomycin, paeciloxazine, myrtucommulone B, 3’-deoxy-hanasanagin, α-tocotrienol, tocopherol and so on, which poissess physiological functions such as antibacterial, antioxidant, anticancer and so on. Therefore, WFB, WIB and AIB have drugs development potential. We also find AFB and FMY have variety of physiological active substances, such as 3’-deoxy-hanasanagin, a-tocotrienol, tocopherol, myrtucommulone B, gingerenone A, antibiotic CV1,10-membered macrolides, cycloserine, niacin, pantothenic acid、choline, valine, glutamate, histidine, leucine, arginine, tyrosine, tryptophan, pro line, carnitine, acetylcarnitine, mannitol, trehalose, PA, PE, PC, PS and so on, and meanwhile there were no common fungi toxic substances detected, therefore, AFB and FMY have the potential to be developed as health products.2 Metabolomic analysis of the mycelia of Isaria cicadae after incubation for different timeMetabolites in the mycelia of Isaria cicadae at different incubation time were determined by LC-MS, and the metabolite differences were identified with multivariate analysis methods such as PCA and OPLS-DA. PCA and OPLS-DA demonstrated that the metabolites in mycelia of Isaria cicadae varied significantly at different incubation time. According to the metabolites in the mycelia of Isaria cicadae analyzed both in positive mode and in negative mode, the incubation time can be divided into three periods, i.e. prophase, metaphase, anaphase. In the prophase, Isaria cicadae produced higher content of cytochalasin E, inositol, GABA, acetylcarnitine, linoleic acid and so on, which possess the functions of infecting the host, early signal transducting and oxidating for energy. In the metaphase, the mycelia of Isaria cicadae had higher contents of mannitol, trehalose, linolenic acid, citric acid, pyruvic acid,7,8-dihydroxy-oleic acid and so on, which have the functions of stress tolerance and antioxidant activities. There were also two antibiotics torularhodin and 5-aminolevulinic acid reached the maximum at this period. In the anaphase, the mycelia of Isaria cicadae contained higher contents of pro line,2,4-diaminobutyric acid,3’-deoxy- hanasanagin, ulvaline, gibberellin, niacinamide and so on, which have the functions of stress tolerence, antioxidant activity, cytoprotectivity, and sporogenesis. We found that niacinamide were possibly related to the change of vegetative growth to reproductive growth and sporogenesis in Isaria cicadae. The metabolites of gibberellin, ulvaline and δ-aminolevulinic acid were possibly related to sporogenesis or spore maturation. It is worth of further studying that gibberellin was produced and accumulated very swiftly at the anaphase. According to metabolic characteristics of Isaria cicadae, it is recommended that the fungus could be incubated for 7-11 days for maximum production of pharmaceutical or healthy metabolites.