Antibacterial compound produced by Pseudomonas aeruginosa strain UICC B-40, an endophytic bacterium isolated from Neesia altissima

Abstract

This study's aim was to determine the identity of antibacterial compounds produced by Pseudomonas aeruginosa strain UICC B-40 and describe the antibacterial compounds' mechanisms of action for damaging pathogenic bacteria cells. Isolation and identification of the compounds were carried out using thin layer chromatography (TLC), nuclear magnetic resonance (NMR) spectroscopy and liquid chromatography mass spectrometry (LC-MS) analyses. Antibacterial activity was assayed via minimum inhibitory concentration (MIC) and the antibacterial compound mechanism was observed morphologically through scanning electron microscopy (SEM). This study successfully identified the (2E,5E)-phenyltetradeca-2,5-dienoate antibacterial compound (molecular weight 300 g/mol), composed of a phenolic ester, fatty acid and long chain of aliphatic group structures. MIC values for this compound were determined at 62.5 μg/ml against Staphylococcus aureus strain ATCC 25923. The mechanism of the compound involved breaking down the bacterial cell walls through the lysis process. The (2E,5E)-phenyltetradeca-2,5-dienoate compound exhibited inhibitory activity on the growth of Gram-positive bacteria.

Isolation and structure elucidation of phenazine derivative from Streptomyces sp. strain UICC B-92 isolated from Neesia altissima (Malvaceae)

“…In addition, the differences between the gene clusters responsible for the phenazines biosynthesis among different Streptomyces species (13) that may lead to the diverse phenazine structural derivatives produced by the bacteria at different levels (39). Although phenazines are generally isolated from Pseudomonas, Streptomyces and several other microbial genera from soil and marine habitats, however, many endophytic Streptomyces species associated with various plants are also capable in producing this secondary metabolite compounds (12,13). This suggests that the endophytic microbial group is one source of potential natural sources in the discovery of new antimicrobial compounds.…”

“…Isolation of bioactive compound. Isolation of antibacterial compound from actinomycetes was conducted according to the method described by Pratiwi et al (12) and Saha et al (22) as follows: selected endophytic actinomycetes strain that showed highest antagonistic activity was sub-cultured on ISP2 medium and incubated for 7 days. Spores of the endophytic actinomycetes strain were inoculated into 500 mL of ISP2 broth medium (pH 6.75) in a 1 L Erlenmeyer flask and incubated in shaking incubator (100 rpm) at room temperature for 5 days.…”

“…The antibacterial activity assay was conducted using the disc diffusion method described by Pratiwi et al (12) and Schwalbe et al (25). Pathogenic bacterial isolates were inoculated onto 50 mL NB medium (Merck) in a 250 mL Erlenmeyer flask and were incubated at 37 ºC for 18 h. 200 µL of 10 5 CFU/mL of each pathogenic bacterial cultures was applied to the surface of the NA plate (15 cm diam.).…”

“…Our previous study on discovery of new compound from microbial endophytes associated with N. altissima reported that three endophytic bacterial strains, viz, Pseudomonas aeruginosa strain UICC B-40 and strain UICC B-93, and Pseudomonas azotoformans strain UICC B-91, exhibited antibacterial activities against Bacillus cereus ATCC 10876, Escherichia coli ATCC 25922, Salmonella Typhimurium ATCC 25241, Shigella flexneri ATCC 12022, and Staphylococcus aureus ATCC 25923 (11). The (2E,5E)-phenyltetradeca-2,5-dienoate (MW = 300 g/mol) bioactive com-pound was isolated and determined from fermentation extract of P. aeruginosa strain UICC B-40, a bacterial endophyte strain from N. altissima (12).…”

Bacterial endophytes from mangrove leaves with antibacterial and enzymatic activities

“…Member of Pseudomonas are described as non allergenic, non-pathogenic, and non toxic toward people, wild life or domestic animal. Pseudomonas also has great potential on producing antibiotic bioactive potential such as indole derivatives, phenazines, pyrrolnitrin-type antibiotics, glycolipids, another substances (Pratiwi et al, 2017). Wu et al (2018) evaluated P. aeruginosa L10 as biosurfactant producing and excellent hydrocarbondegrading bacteria isolated from roots, stems and leaves of a Reed Phragmites australis).…”