一株红树林来源放线菌的抗菌活性物质OA北大核心CSTPCD

Mangrove-derived microorganism is a promising and important resource of novel natural products and lead compounds for drug discovery.This study aimed to find microbial secondary metabolites with novel structures.Based on the bioactive-guided screening of mangrove-derived actinomycetes,Streptomyces sp.GP3T5 was studied owing to its antibacterial,antibiofilm and anti-fungi activities.Three compounds(1-3)were isolated from the fermentation broth by organic solvent extraction,reversed-phase chromatography,Sephadex LH20 gel chromatography,and preparative high-performance liquid chromatography.Their structures were identified as pyrisulfoxin A(compound 1),collismycin A(compound 2),and echinomycin A(compound 3),respectively,via high resolution electrospray ionization mass spectroscopy(HRESIMS),nuclear magnetic resonance(NMR),ultraviolet(UV)spectroscopy.The activity evaluation of compounds 1-3 revealed that all three compounds showed antibacterial and antibiofilm activities.Compound 3 showed potent antibacterial activity against foodborne pathogens with minimum inhibitory concentrations(ρMIC)of 0.06 µg/mL for Listeria monocytogenes and Streptococcus agalactiae.The minimum biofilm inhibitory concentrations(ρMBIC)of compounds 1-3 against Acinetobacter baumannii were 32 µg/mL,16 µg/mL,and 1 µg/mL,respectively.Compounds 2 and 3 showed good antifungal activity against plant pathogenic fungi,with half maximal inhibitory concentrations(IC50)≤10 µg/mL and≤1 µg/mL,respectively.In conclusion,these results on strain GP3T5 derived from mangroves provide valuable insights for further exploration of bioactive compounds from mangrove soil microorganisms.