ABSTRACT
In this study, the anti-biofilm compound of 2,6-Di-tert-butyl, 1,4-benzoquinone was purified from Nocardiopsis synnemataformans (N. synnemataformans) RMN 4 (MN061002). To confirm the compound, various spectroscopy analyses were done including ultraviolet (UV) spectrometer, Fourier transform infrared spectroscopy (FTIR), analytical high-performance liquid chromatography (HPLC), preparative HPLC, gas chromatography-mass spectroscopy (GC-MS), liquid chromatography-mass spectroscopy (LC-MS), and 2D nuclear magnetic resonance (NMR). Furthermore, the purified compound was shown 94% inhibition against biofilm-producing Proteus mirabilis (P. mirabilis) (MN396686) at 70 µg/mL concentrations. Furthermore, the metabolic activity, exopolysaccharide damage, and hydrophobicity degradation results of identified compound exhibited excellent inhibition at 100 µg/mL concentration. Furthermore, the confocal laser scanning electron microscope (CLSM) and scanning electron microscope (SEM) results were shown with intracellular damages and architectural changes in bacteria. Consecutively, the in vivo toxicity effect of the compound against Artemia franciscana (A. franciscana) was shown to have a low mortality rate at 100 µg/mL. Finally, the molecular docking interaction between the quorum sensing (QS) genes and identified compound clearly suggested that the identified compound 2,6-Di-tert-butyl, 1,4-benzoquinone has anti-quorum sensing and anti-biofilm activities against P. mirabilis (MN396686).
ABSTRACT
BACKGROUND: Worldwide, multi-drug resistant Klebsiella pneumoniae (K. pneumonia) and their virulence's were contributed more in the multi-drug resistant effect. According to the World Health organization report, it is an emerging thread in developing countries and also comes under first ever critical list. In this context, the current study was concentrated on detection of extended spectrum beta lactamase (ESBL) producing strain and their antimicrobial susceptibility study of K. pneumoniae. MATERIALS AND METHODS: Firstly, the multi-drug resistant effect of the K. pneumoniae was identified from specific CLSI guidelines recommended antibiotics by disc diffusion method. Consecutively, the primary ESBL identification test was performed using ceftazidime and cefotaxime, followed by double disc combination and phenotypic confirmation tests using ceftazidime/clavulanic acid and cefotaxime/clavulanic acid. Finally, the minimum inhibition concentration of some important sensitive antibiotics were performed against selected K. pneumoniae was confirmed by micro broth dilution method. RESULTS AND CONCLUSIONS: The current result was most favorable to selected K. pneumoniae with more multi drug resistant characteristic nature. All the performed antibiotics were almost more sensitive to selected K. pneumoniae. The effective antibiotics of piperacillin was also exhibited more resistant effect against tested bacteria and it cleaved the bacterial enzyme clearly. The present result of primary ESBL identification test result was exhibited with ≤22 mm and ≤27 mm against ceftazidime and cefotaxime were observed respectively. Followed result of double disc combination and phenotypic confirmation experiments results were clearly stated that the selected K. pneumoniae was ESBL producer. The ceftazidime, cefotaxime and ceftazidime/clavulanic acid and cefotaxime/clavulanic acid were exhibited with merged zones and ≥5 mm zones around the combination disc when compared with disc alone were observed. All the ESBL detection test results were clearly indicated that the selected K. pneumoniae strain was ESBL producer.
