Isolation And Identification Of The Secondary Metabolites With Antimicrobial Activity From Achromobacter Sp.

Soil microbial natural products are important sources for the discovery of new antibiotics.In this paper,strains were isolated from soil environments of different sources,and a strain of H6 with good antimicrobial activity was obtained by screening antimicrobial activity.At the same time,the strain identification and culture conditions were explored,and the active metabolites were isolated,purified and structurally identified.Finally,the isolated natural products were tested for antimicrobial activity and antitumor activity analysis.1.Isolation and identification of H6 strain:The isolates of 56 strains were analyzed for antimicrobial activity against Candida albicans,Staphylococcus aureus,Aeromonas veronii,Erwinia,Aeromonas hydrophila and other strains.Through initial screening,four strains of microorganism exhibited antimicrobial activity Among which,H6 strain displayed the most strong antimicrobial activity.At the same time,HPLC analysis of the metabolites of the strains revealed that two of the metabolites were identical to the H6 strain and the other had fewer metabolites.Therefore,the H6 strain was further studied in this study.By 16S rRNA gene sequence analysis,morphological observation,culture characteristics,physiological and biochemical characteristics,strain H6 was identified as Achromobacter sp.2.The exploration of culture conditions of strain H6 and the analysis of physicochemical properties of secondary metabolites:After preliminary fermentation optimization experiments,the number of days of fermentation was determined to be 5 days.The analysis of physical and chemical properties of the metabolites showed that the active ingredients were stable to heat,2-butanone it has the best extraction effect and has certain solubility in various organic solvents.3.Isolation,Purification and Identification of antimicrobial Active Substances of H6 Strain:Five compounds were isolated from 10L of Achromobacter sp.H6 fermentation broth by centrifugation,solvent extraction,rotary evaporation,analytical HPLC and preparative HPLC.The structure of the compound was analyzed by MS and NMR.The structural compound A in which two active compounds are obtained is phenazine-1-carboxamide,and the compound B is phenazine-1-carboxylic acid.and other compounds structures are being analyzed.4.Compounds A and B acted on mouse melanoma cells B16.The results showed that both compounds could change the morphology of B16 cells,and the effect of compound B was more obvious.Phenazine-1-carboxamide and phenazine-1-carboxylic acid are all phenazine compounds,which not only have antimicrobial activity,but also have antitumor activity.