Chemical pesticides have an impact on other living organisms in addition to their intended target organisms. Any chemical pesticide is therefore made safe for use by examining its biological characteristics and side effects. The present study was aimed at determining the resistance efficiency of six bacterial isolates obtained from malathion-contaminated soils. Bacteria were isolated from soil samples collected in Adhamiya, Baghdad, Iraq. Biochemical tests and VITEK 2 compact equipment were used to identify the bacterial isolates. Primary and secondary screening tests were conducted on the bacterial isolates for resistance against malathion pesticides. The optimal bacterial growth conditions were determined in malathion-contaminated media. The results demonstrated that the bacterial isolates 1, 3, 4, and 8 grew best on malathion-contaminated (100 mgL-1) mineral salt medium (MSM). Isolates 1 and 2 had a MIC of 500 mgL-1, where they continued to grow until the seventh day of incubation. Pseudomonas aeruginosa, Pseudomonas putida, Aeromonas hydrophilia, and Escherichia coli were the identified bacterial isolates. These isolates showed optimal bacterial growth in the test conditions (temperature, incubation period, and pH), indicating their efficiency and ability to degrade malathion. The highest average growth of P. aeruginosa at 35 °C was 70.08 mm, while that of P. putida was 40.10 mm during the 7-day incubation period. Also, the highest values of average growth were observed in the same bacteria at pH 7, with a value of 26.98 mm. The findings of this study reveal that Pseudomonas aeruginosa and Pseudomonas putida were the best bacterial isolates for biodegrading malathion.
In this study, we investigated the prevalence of aminoglycosides modifying enzymes (AMEs)-encoding genes, including aac(3′)-ΙΙ, ant(3′′)-Ι, aph(3′)-VΙ, and aac(6′)-Ιb-cr and their potential effect on the development of resistance to aminoglycosides and fluoroquinolones in clinical isolates of Klebsiella pneumoniae. According to the phenotypic and biochemical characteristics of 150 clinical samples, 50 (33%) isolates were identified as K. pneumoniae. These isolates were collected from different clinical sources, including urine (15, 30%), blood (12, 24%), sputum (9, 18%), wounds (9, 18%), and burns (5, 10%). The minimum inhibitory conce
... Show MoreAn experiment was conducted to study the effect of four isolates of Pseudomonas spp. on the growth of two plants Radish & Cowpea and on the concentrations of macro elements & microelements . This experiment included two parts , the 1st. part included isolation and characterization of 4 isolates of Pseudomonas bacteria from local Iraqi soils Baghdad . The 2nd part included planting two plants Radish & Cowpea in plastic pots size 5Kg -soil in the green house Biology Dept. College of Science , after planting we added the isolates to the pots , and after 50 days, the growth parameters length , fresh and dry weight , percentage of ger
... Show MoreThe aim of this study is to evaluating the antibacterial activity of Laurus nobilis leaves extract on E. coli isolates. Maceration and Soxhlet apparatus were used to prepare aqueous and methanolic extracts; total phenolic content and 2,2-diphenyl-1-picrylhydrazyl (DPPH) were conducted to determine the active compounds in the extracts. The results showed that both Laurus nobilis methanolic and aqueous extracts have a noticeable effect on scavenging free radicals. Free radical scavenging activity. The total phenolic contents were 28.60 ±0.12 and 16.58 ±0.11mg/g in 50 mg/ml, in methanolic and aqueous extracts respectively. The antibacterial activity of Laurus nobilis leaves extracts showed that the methanolic extract was more effective than
... Show MoreThis study investigated the prevalence of quinolones resistance proteins encoding genes (qnr genes) and co-resistance for fluoroquinolones and β-lactams among clinical isolates of Klebsiella pneumoniae. Out of 150 clinical samples, 50 isolates of K. pneumoniae were identified according to morphological and biochemical properties. These isolates were collected from different clinical samples, including 15 (30%) urine, 12 (24%) blood, 9 (18%) sputum, 9 (18%) wound, and 5 (10%) burn. The minimum inhibitory concentrations (MICs) assay revealed that 15 (30%) of isolates were resistant to ciprofloxacin (≥4µg/ml), 11 (22%) of isolates were resistant to levofloxacin (≥8 µg/ml), 21 (42%) of isolates were re
... Show MoreThe development of new cephalosporins with improved activity against resistant microbes, such as, MRSA (methicillin resistant Staph. aureus), P. aeruginosa, is of high potential. Chemical synthesis of two new series of thiadiazole linked to cysteine (series 1) and cephalosporins containing thiadiazole linked to cysteine through disulfide bond (series 2) were achieved. The chemical structures of the synthesized compounds were confirmed using spectral (FT-IR, 1H-NMR) and elemental microanalysis. The incorporation of privileged chemical moieties, such as, thiadiazole, Schiff base, cysteine and sulfonamide, has been found to have great contribution to the antimicrobial activities. Compounds of series 1 (1
... Show MoreSome Factors determining the virulence of Escherichia coli ( E. coli ) isolates were studied ,of 25 isolates , 17(group A) uropathogenic E. coli ,6 (group B) infected gastrointestinal tract , 2 (group C) infected wound , beside these group we use the standard strain E. coli HB101 as control group. The twenty five isolates were tested for adherence capability to human buccal cavity epithelial cells by in vitro experiment . The results showed that all isolates have different adhesion capability with mean ranging from (14.35±11.39) to (33.80 ± 22.68) bacteria / epithelial cell It was noticed that isolates EU9, ES6, EW17 displayed high adhesive capability with mean value (33.80 ± 22.68), (32.60 ± 21.19), (29.90±22.50) bacteria /epithelial
... Show MoreLactobacillus is one of Lactic Acid Bacteria group, they are known to exhibit antagonistic activity against pathogenic organisms. This study evaluates the protective effect of Lactobacillus acidophilus Crud Bacteriocin like substance against growth of some food borne pathogenic bacteria. Antimicrobial effect of crud bacteriocin like substance was tested against the growth of S. typhi and S. aureus that isolated from food samples by agar well diffusion assay.
The results showed that the crud extract of bacteriocin like substance had antibacterial activity against the two tested bacteria, and the effect against S. typhi was greater than that of S. aureus , the zone of inhibition was (15)mm against S.&n