Secondary Metabolites And Bioactivities Of Deep Sea Cold-spring-derived Fungal Strains Aspergillus Nidulans And Talaromyces Funiculosus

Since the beginning of the 20^th century,researchers at home and abroad have successively isolated a large number of secondary metabolites from marine fungi.Most of these natural compounds have special structural characteristics and diverse biological activities,which can not only provide scientific guidance for the development and utilization of marine microbial resources,but also play an important role in the mechanism research and new drug development.As time goes on,the secondary metabolites produced by microorganisms in more extreme living environment become an important focus of exploration.Cold spring microorganisms have unique metabolic pathway and genetic background due to their adaptation to special growth environment.For the abundant of diversities of biological species and chemical types of metabolites,it is more likely to find novel chemical structures with application values.Therefore,the study selected cold spring microorganism to study,in order to explore natural products with better activity as alternative lead compounds for drug development,so as to enrich sources of drug lead compounds.In this paper,two cold-spring-derived fungi,Aspergillus nidulans SD-531 and Thalanomyces funiculosus SD-523,were selected to find their secondary metabolites and explore their biological activities.In the systematic separation of crude extracts,a variety of chromatography methods were used as the separation methods and TLC and HPLC analysis were used as detection methods.Including thiodiletpiperazine,peroxides,oxaxanthone,terpenes,etc,thierty-four compounds were isolated and identified,while four new structures were found.Twenty eight compounds(AK1*-AK28)were isolated from fungus A.nidulans SD-531.Four of them were new compounds,including three thiodiketpiperazines(AK1*-AK3*)and one peroxide(AK4*).Six known compounds(TF1-TF6)were isolated from T.funiculosus SD-523.Some of the isolated compounds were evaluated for antibacterial,antifungi and antitumor activities.Compounds AK1*-AK3*and AK5-AK7 had cytotoxic activity against the tumor cell line Huh 7.5,with IC₅₀ values ranging from 0.25-19.0?mol/L.AK1*-AK19 had antimicrobial activities against 11bacterium and 8 fungi with MIC values ranging from 0.5-64?g/m L,while AK5,AK8and AK10 displayed broad spectrum and significant activities among the tested samples.In this paper,the new compounds were isolated and identified from the extracts of cold spring fungi.The diversity of secondary metabolites was enriched and the activities of the compounds were preliminarily explored.It provides a scientific reference for the effective exploration and application of cold spring microbial resources.