Metabolic Differences Of Cynomorium Songaricum In Different Developmental Stages And The Relationship With Dominant Endophytic Fungi

Cynomorium songaricum Rupr.,a holoparasitic plant that grows in the desert and has important dietetic and medical value.Modern pharmacological studies have shown that C.songaricum has the functions of promoting anti-cancer,anti-fatigue,anti-aging,anti-stress,scavenging free radicals,and has no side effects.This benefited from a variety of unique bioactive components,such as flavonoids,triterpenoids,organic acids and polysaccharides based on pharmacological studies.However,the medicinal efficacy of C.songaricum collected in different seasons varies greatly,and it is still unclear that the difference in the transformation and accumulation of its main metabolites.In this paper,UPLC-QTOF/MS and NMR were used to study the metabolomics of C.songaricum in different growth stages,so as to explore the metabolic differences and regularity of C.songaricum in different phenological periods during one cycle.Meanwhile,through the analysis of genome sequencing and ITS2 diversity to study the endophytic fungi of C.songaricum in different developmental stages,and the core endophytic fungi in each developmental stage of C.songaricum were screened to analyze the correlation with the differential metabolites based on UPLC-QTOF/MS analysis.The results of metabolomics study showed that there were thirty and sixteen compounds with significant differences based on UPLC-QTOF/MS and NMR,respectively,which were distributed in flavonoids,organic acids,sugars and amino acids.Among them,the content of secondary metabolites such as catechins and procyanidins accumulated more in the unearthing and maturing stages,while other differential compounds accumulated more in the tubercle,sprouting and atrophy stages.The differential metabolic pathways of C.songaricum in different stages involved in flavonoids,sugar,amino acid and other pathways.The analysis of genome sequencing and diversity ITS2 of endophytic fungi showed that some shared endophytic fungi existed in every developmental stage of C.songaricum,while some endophytic fungi only existed in a certain developmental stage.According to the total abundance,ten dominant strains were selected,and eight of them were identified,which were Aspergillus,Dothideomycetes,Sordariomycetes,Fusarium,Gibberella,Lentinula,Plectosphaerellaceae and Candida,respectively.The analysis of the correlation with dominant strains and differential metabolites showed that there was a significant correlation between core endophytic fungi and differential secondary metabolites,which indicated that core endophytic fungi played an important role in the accumulation,production and other life activities of C.songaricum in different developmental stages.The endophytic fungi of C.songaricum in different developmental stages have the functions of improving the antibacterial,antiviral and antioxidant activities,but when C.songaricum enters Atrophy stage,it will cause diseases and accelerate the decline of C.songaricum.This study provides scientific basis for people to understand the metabolic differences and the correlation with dominant endophytic fungi of C.songaricum in different developmental stages,which showed that the advantage of using combination of UPLC-QTOF/MS and NMR metabolic platforms to give complementary,objective,comprehensive and accurate data,and may provide help for people to establish new ideas and methods for the production,collection,quality evaluation and use as medicinal materials of C.songaricum in different developmental stages.