Background: Suppression of quorum sensing (QS) that regulates many virulence factors, including antimicrobial resistance, in bacteria may subject the pathogenic microbes to the harmful consequences of the antibiotics, increasing their susceptibility to such drugs. Aim: The current study aimed to make an aqueous crude extract from the soil Proteus mirabilis isolate with the use of the gas chromatography-mass spectrometry (GC-MS) technique for its analysis, and then, study the impact of the extract on clinical isolates of Pseudomonas aeruginosa. Methods: Preparation of crude extracts from P. mirabilis (both organic and aqueous), which were then analyzed by GC-MS to detect the bioactive ingredients. Furthermore, the extract’s capability to interfere with both the expression of the QS of P. aeruginosa and its antibacterial resistance was examined. Results: The highest GC-MS peak (37.11%.) appeared for 1,3-benzodioxole, 4-methoxy-6-(2-propenyl), along with the presence of other components of antibacterial activities. When the aqueous extract was added to the culture of two multi-drug resistant (MDR) P. aeruginosa, a significant reduction in the expression of the QS regulatory gene LasI occurred, indicating its interference with QS. Moreover, upon adding the extract to the culture of P. aeruginosa (MDR) and then subjecting it to Amikacin and Colistin, already not effective on the bacteria, the isolates became more susceptible to these antibiotics showing zones of inhibition of 25 and 17 mm, respectively. Conclusion: The crude aqueous extract of the soil P. mirabilis isolate might be a potential producer of QS inhibitors with antibacterial activities that render the MDR P. aeruginosa more susceptible to antibiotics to whom they already exerted resistance.
Background: Alternative natural therapy by plants extracts had opened wide door for the use of natural products as an alternative therapy instead of many antibiotics and drugs , which had many harmful side effects.Also, an increased interest has been centered on the industrial wastes, especially plant raw materials which contain phenols (e.g. Pomegranate peel and Bay leaves) which is a sources of natural antioxidants ,which are on the contrary of synthetic antioxidants that had restrict use due to their health risks , carcinogenesis and toxicity .
Objectives :This study was done to fi
... Show MoreThe present study was undertaken in order to investigate the role of gentamicin in the gene expression of toxA in Pseudomonas aeruginosa isolated from cow mastitis. A total of ten P. aeruginosa strains originally isolated from cows infected with mastitis. Agar dilution methodology was performed to determine the minimal inhibitory concentration of gentamicin, all of which developed resistance toward gentamicin. The findings presented here demonstrated that all these strains harboured toxA depending on PCR-based assay. Nonetheless, RT-PCR technique revealed a wide variation in expression of toxA. Moreover, the cultivation of P. aeruginosa in the presence of gentamicin, significantly (P< 0.05), induced the expression of toxA, in addition to th
... Show MoreFifty isolates of Psel.ldomonas aeruginosa were obtained from
(170) isoiates of ctlinical cases. Sensitivity of the isolates t() antibiotic leveled showed a high resistance to cefotaxime, ceftazidime, gentamicin and tobramycin. To less extent was the resistance to· amikacin and ciprofloxacine. All isolates of Pseudomonas aeru,ginosa were highly sensitive tocefepime and imipenem.
Eighty six perce
... Show MorePseudomonas aeruginosa produces an extracellular bioï¬lm matrix that consists of nucleic acids, exopolysaccharides, lipid vesicles, and proteins. Alginate, Psl and Pel are three exopolysaccharides that constitute the main components in biofilm matrix, with many biological functions attributed to them, especially concerning the protection of the bacterial cell from antimicrobial agents and immune responses. A total of 25 gentamicin-resistant P. aeruginosa selected isolates were enrolled in this study. Biofilm development was observed in 96% of the isolates. In addition, the present results clarified the presence of pelA and pslA in all the studied isolates. The expression of these genes was very low. Even though all biof
... Show MorePseudomonas aeruginosa produces an extracellular bioï¬lm matrix that consists of nucleic acids, exopolysaccharides, lipid vesicles, and proteins. Alginate, Psl and Pel are three exopolysaccharides that constitute the main components in biofilm matrix, with many biological functions attributed to them, especially concerning the protection of the bacterial cell from antimicrobial agents and immune responses. A total of 25 gentamicin-resistant P. aeruginosa selected isolates were enrolled in this study. Biofilm development was observed in 96% of the isolates. In addition, the present results clarified the presence of pelA and pslA in all the studied isolates. The expression of
... Show MoreFifteen local isolates of Pseudomonas were obtained from several sources such as soil, water and some high-fat foods (Meat, olives, coconuts, etc.). The ability of isolates to produce lipase was measured by the size of clear zone on Tween 20 solid medium and by measuring the enzymatic activity and specific activity. Isolate M3 (as named in this study) was found to be the most efficient for the production of the lipase with enzymatic activity reached 56.6 U/ml and specific activity of 305.94 U/mg. This isolate was identified through genetic analysis of the 16S rRNA gene. and it was shown that the isolate M3 belongs to Pseudomonas aeruginosa with 99% similarity. The DNA of isolate M3 was extracted and lipase gene was amplified through PCR tec
... Show MoreThe aim of this research is to evaluate the effect of glucose and sodium chloride on biofilm formation by bacteria causing wound infection. For this purpose, 1% and 2% concentration of each of glucose and sodium chloride were used to test the biofilm formation potential of Staphylococcus aureus and Pseudomonas aeruginosa, which were the most common abundant bacteria that cause infection by biofilm. Each of the concentrations was kept in contact with the pathogenic bacteria for 24 hours. After the period of incubation, the concentration of 1% of glucose enhanced moderate biofilm formation capacity for (66% and 80%) on both bacteria respectively. The concentration of 2% glucose, on the other hand, led to a weak biofilm fo
... Show MoreThe results of the phytochemical analysis of the crude aqueous and
methanolicextracts of Myrtle (Myrtuscommunis), peppermint (Menthapiperita) and
Sweet basil(Ocimumbasilicum) contain active compounds : Phenols, Flavonoids and
Tannins and missing of Steroids and Coumarines in all extract but Saponins and
Alkaloids found in methanolicextract only, while terpens were present in peppermint
and basiland absent in Myrtle. Administratingto animals with different extracts
showed no effect on serum Acetylcholinesterase (AchE) compared withthese fed on
ethanol liquid diet, Methanolicand aqueous extracts of Myrtle, peppermint and
basilin the serum of decreased Acetylcholinesterase level significantly(p≤0.05)[(1.25
ΔpH/
Klebsiella pneumoniae is one of common hospital-acquired bacteria causing nosocomial pneumonia, urinary tract infections, and intra-abdominal infections. The aim of this study is investigating the Modulation effect of Zinc Oxide nanoparticles (ZnO NPs) against multidrug resistant K. pneumonia which was isolated from Respiratory Tract Infections (RTIs). The results of isolation and characterization of bacterial specimens showed that 20.81% of RTIs were Klebsiella pneumoniae. The strongest isolate showed resistant for most usable antibiotics selected. Simultaneously, ZnO NPs were produced by an aqueous extract of Green Tea leaves as a reducing and stabilizer agent. The Ultraviolet-Visible (UV-Vis) spectrum was indicated a successful produc
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