The purpose of this study to synthesize and characterize silver nanoparticles using phenolic compounds obtained from Camellia sinensis, to test the antibacterial properties of biosynthesized nanoparticles on the formation of biofilms in multidrug-resistant Pseudomonas aeruginosa. Ten isolates of P. aeruginosa were obtained from the Genetic Engineering and Biotechnology Institute laboratories of the University of Baghdad. By using the VITEK-2 system and culturing the isolates on cetrimide agar, the diagnosis was confirmed. Camellia sinensis silver nanoparticles (CAgNPs) were created using an extract of the plant's aqueous and methanolic leaves. Based on the results of the nanoparticle synthesis, spherical nanoparticles that may be single or mixed were included in both the aqueous and methanolic extracts of silver nanoparticles. By comparing their retention times to those of the reference compounds, the HPLC findings revealed that two phenolic compounds (gallic acid and caffeine) had been discovered. Utilising the disc diffusion technique, the antibacterial activity of (CAgNPs) was assessed. The results indicated that the methanolic (CAgNPs) extract was more effective than the aqueous (CAgNPs) extract at 375 and 750 ppm, giving the highest inhibition zone 17.67 and 21.33 mm, respectively, when compared to the aqueous (CAgNPs) extract, which produced inhibitory zones 13.00 and 16.33 mm, respectively. The MIC findings indicated that the methanolic CAgNPs extract was more effective than the aqueous CAgNPs extract; the MIC of the methanolic CAgNPs extract was 23.43 μg/ml in all P. aeruginosa isolates, except the isolates No. 9 and 10, which was 11.718 μg/ml. While in the aqueous extract, the MIC in all P. aeruginosa isolates was 187.5 μg/ml, with the exception of isolates No. 9 and 10, which was 93.75 μg/ml. Additionally, the methanolic CAgNPs extract entirely inhibited P. aeruginosa from building a biofilm when used at 23.43 μg/ml. However, at 46.87 μg/ml of the aqueous CAgNPs extract, totally reduced the biofilm forming activity on P. aeruginosa isolates
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The 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
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The aim of this study is to synthesize an easy, non-toxic and eco-friendly method. Silver nanoparticles which were synthesized by leaf extract of mint were characterized by UV-Visible Spectroscopy which appears UVVisible spectrum of demonstrated a peak 448 nm corresponding to surface Plasmon resonance of silver nanoparticles, Fourier Transform Infrared Spectroscopy (FTIR); functional groups involved in the silver nanoparticles synthesis were identified, the presence of silver nanoparticles was confirmed by X-ray diffraction (XRD) and Atomic Force Microscope (AFM) analysis clearly illustrated that the shape of silver nanoparticles was spherical and the size of the silver nanoparticles has been measured as 55- 85 nm. Evaluation of its antimic
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A laboratory experiment studied the effects of the green tea (Camellia sinensis L.) aqueous extract at concentrations of 10, 20, and 30 ppm on the germination and growth traits of the mung bean (Vigna radiata L.), carried out in 2021 at the Department of Biology, College of Education for Pure Sciences, Ibn Al-Haitham, University of Baghdad, Iraq. The results showed that Camellia sinensis green tea extracts played a vital role by significantly boosting all the examined characteristics compared with the control treatment. The aqueous extract of Green tea at concentrations of 10 and 20 ppm gave the best performance in increasing germination rates, germination speed, plant promoter indicator, and seedling strength compared with the control trea
... Show MoreNutrient agar medium with various concentrations of cefotaxime was used for isolation spontaneous mutants from wild type strain of P.aeruginosa PHA-1. Eighty-two mutants were successfully isolated with the viable count 52×107 , these mutants were confirmed as spontaneous not physiological adaption mutants by reculture on the same medium. Then, wild type PHA-1 and mutants were examined for production pyocyanin; a blue greenish pigment was clearly noticed on King A medium. Remarkably the mutant strain named S300-8 was distinguished in productivity in comparison with wild type strain PHA-1; the amount of pigment was 56.0667mg/l and 74.53mg/l respectively. In addition, pyocyanin produced by mutant strain S300-8 revealed a potent efficacy again
... 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
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Owing to high antibacterial resistance of Pseudomonas aeruginosa, it could be considered as the main reason behind the nosocomial infections. P. aeruginosa has a well-known biofilm forming ability. The expression of polysaccharide encoding locus (pelA gene) by P. aeruginosa is essential for this ability. The purpose of the current research was to determine the biofilm formation in P. aeruginosa isolated from clinical samples and to evaluate the role of the selected PelA gene in biofilm formation using PCR method in Iraqi patients. Results revealed that 24 (96%) isolates were found to have the ability to form biofilm that was remarkably related to gentamicin resistance. Moreover, the pelA gene was found in all biofilm-producers. In c
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