World Journal of Experimental Biosciences
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Antibacterial Activity of Gaultheria procumbens, Thymus vulgaris, Peganum harmala, and Bergamot (Citrus bergamia) Essential Oils against Enterococcus raffinosus Isolated from Urinary Tract Infections
Get PDFThe discovery of alternative antimicrobial agents against resistant bacteria has been a major target for microbiologists and physicians, especially in recent years, because the resistance to antibiotics has increased. No previous study has investigated the antibacterial effects of essential oils prepared from Gaultheria procumbens, Thymus vulgaris, Peganum harmala, and Bergamot (Citrus bergamia) against Enterococcus raffinosus. The present study aims to investigate the antibacterial activity of the essential oils of the above medicinal plants against E. raffinosus in vitro. In the present study, essential oils were extracted from the above four medicinal plants. For evaluating the antibacterial effect of the essential oils, three isolates of E. raffinosus were isolated from 44 urine samples collected from patients with urinary tract infections (UTIs). Only one isolate was multidrug-resistant (MDR) to commonly used antibiotics. The microdilution method on microtiter plates and the agar diffusion method were used to check the susceptibility of E. raffinosus to the essential oils. The study showed that the essential oil of T. vulgaris showed the highest antibacterial activity against E. raffinosus, followed by P. harmala. The present study showed a moderate antibacterial effect of G. procumbens essential oil against E. raffinosus. The present study showed no antibacterial effect of the essential oil of Bergamot against E. raffinosus. It can be concluded from the study that the antibacterial effect of the essential oils prepared from G. procumbens, T. vulgaris, and P. harmala against MDR-E. raffinosus, that is why these oils can serve as a novel antibacterial agent against E. raffinosus infections. 
Extraction and purification of chitinase from Bacillus subtilis
Get PDFFour isolates of Bacillus subtilis produced chitinase were isolated from soil. The bacterial isolates were grown in liquid medium supported with different salts and nitrogen sources. The highest produced isolate was selected for further experiments. Different method was used to purify the enzyme. The optimum condition for enzyme activity was evaluated in present study. B. subtilis A3 gave the highest enzyme production. The different purification steps were followed to purified casein from B. subtilis A3. The produced enzyme was precipitated at 80% of saturated solution of ammonium sulphate. The salt was eradicated by dialyzed the yielded enzyme with distilled water. Finally, the enzyme solution was run through ion-exchange chromatography (Sephadex G-100 column). The maximum specific activity (5.1 U/mg of protein) was observed in liquid medium supported with casein and incubated in 30 oC with pH 8
Molecular Frontiers in Modest Labs: Phage Research in Low-Income Settings
Get PDFThe establishment of the World Journal of Experimental Biosciences marks a significant milestone for researchers worldwide. For those of us working in low-income countries, it offers a rare platform to voice not only our scientific findings but also the silent struggles behind them. As a former PhD student in India and now a mentor in Ethiopia (Africa), I write this editorial to reflect on the challenges and quiet triumphs of conducting molecular microbiology, especially phage research, in modest laboratories
Antagonistic Interactions Between Soil-Isolated Actinomycetes and Pathogenic Bacterial Strains
Get PDFBacterial resistance to commonly used antibiotics for treating infections is the biggest challenge facing clinicians. Previous research on antibiotic-producing actinomycetes has been limited. This study aims to explore the potential of identifying actinomycete isolates that may produce antibiotics more effective than current treatments for bacterial infections. Fifty soil samples were collected from various regions in central Iraq to isolate actinomycetes. Ten clinical bacterial isolates of Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, and Enterococcus faecalis, which were resistant to multiple antibiotics, were obtained and maintained for use in experiments. The double-layer of agar and spot assay was used to detect antagonistic interactions between actinomycete and pathogenic bacterial isolates (ten isolates). The Kirby-Bauer method was employed to evaluate the response of these isolates to four different antibiotics (ofloxacin (OF), gentamicin (CN), amoxicillin (AX), vancomycin (VA). The experiments demonstrated successful isolation of actinomycetes and validated the effectiveness of the employed method. The results indicated that the clinical isolates were highly resistant to the antibiotics tested. Nine out of ten isolates showed antagonistic reactions to actinomycete bacteria. This suggests that soil-derived actinomycetes can be isolated and possess strong antagonistic activity against bacteria resistant to various antibiotics. Such isolates could potentially be used to develop more effective antibiotics than those tested in this study.
 
Exploring the Effects of Hydrogen Peroxide on Biofilm Development and Antibiotic Susceptibility
Get PDFHydrogen peroxide is one of the most important chemical compounds that affect the formation of biofilm of microorganisms and response to antimicrobial agents which can be used in war against pathogenic microorganisms in healthcare institutions. The current study aims to highlight the mechanism of the effect of H2O2 on biofilm formation, in addition to the possibility of using it to enhance the ability of antimicrobials to reduce the outbreak of infectious disease. In this review article, the impact of hydrogen peroxide on the susceptibility of pathogenic bacteria to antibiotics will be screened through the role of H2O2 in reducing biofilm formation. Here, the mechanism of the effect of H2O2 on the body of pathogenic bacteria through oxidation stress, eradication of biofilm, destruction of microbial membrane, and inhibition of microbial enzymes. The effect of hydrogen peroxide on biofilm formation depends on the concentration of hydrogen peroxide and the duration of exposure of microorganisms. In some time the low concentrations of H2O2 induce biofilm formation and high concentrations may reduce the biofilm formation (and that may be dependent on the species of microorganism). The effect of H2O2 on biofilm formation is through reducing initial attachment as well as interfering with the maturation and maintenance of biofilm. Hydrogen peroxide has an important role in enhancing antibacterial agents and this may contribute to redrawing the therapeutic strategy in the future. It can be concluded from the present study that H2O2 has a role in reducing the outbreak of infectious diseases and helps in enhancing the antibacterial war, which contributes to enhancing public health.
 
Climate Change Induces Shifts in Infectious Disease Dynamics: Emerging Global Threats
Get PDFClimate change and infectious diseases have been topics of interest for professionals such as Environmental Scientists, Ecologists, Public Health professionals, and Social Psychologists. The relationship between climate change and infectious diseases is complex, affecting the environment, social and economic conditions, and human health. It affects pathogens, vectors, transmission routes, and the human population\u27s susceptibility to diseases. Infectious diseases like malaria, dengue fever, cholera, and influenza are sensitive to climate change, and scientists are focusing on better modeling, preemptive warnings, and new technologies like biosurveillance, artificial intelligence, and vaccine development to reduce the consequences of climate change for new and re-emerging diseases. A combination of multi-level and multi-sectoral efforts and a global approach is required to monitor and respond to future outbreaks. This paper will explore effective measures in preventing diseases related to climate change and the existing scientific evidence to prove its impact on infectious diseases.
 
Study the Effect of Lemongrass and Rosemary Extracts against Bacterial Pathogens
Get PDFThe study aims to study the antibacterial effects of lemongrass and rosemary extracts against different types of bacteria. According to studies, rosemary extract has antibacterial properties against both Gram-positive and Gram-negative bacteria, such as Pseudomonas aeruginosa, Escherichia coli, and Staphylococcus aureus. Bioactive substances including rosmarinic acid and carnosic acid are responsible for the antibacterial properties of rosemary extract. Salmonella enterica, Listeria monocytogenes, and Bacillus cereus are just a few of the microorganisms that lemongrass extract has been shown to have antibacterial activity against. Citral a significant part of the essential oil, is the main cause of lemongrass\u27s antibacterial qualities. It has also been discovered that combining the extracts of lemongrass and rosemary has a synergistic effect that increases the antibacterial action against specific bacteria. It is thought that the various modes of action of the bioactive substances included in these extracts are what cause this synergistic impact. All things considered, the data that is now available points to the possibility of using extracts of rosemary and lemongrass as natural antibacterial agents against a range of harmful microorganisms.
 
Emerging Patterns of Meropenem Resistance in Pseudomonas aeruginosa from Burn Patients: Epidemiological Data from Central Iraq
Get PDFInfected burns are among the most serious clinical cases with high mortality rates, especially when infected with multidrug-resistant (MDR) bacteria. Pseudomonas aeruginosa infection in burns significantly contributes to the high mortality associated with bacterial burn infections. This study aimed to conduct a bio-surveillance of burn cases infected with P. aeruginosa and their resistance to meropenem. A total of 305 burn cases were examined, with samples collected from the burn and wound hospital in Baghdad. Of these, 180 samples came from skin and soft tissue infections (SSTIs) associated with systemic sepsis, 100 from SSTIs, and 25 from minor burn injuries. P. aeruginosa was isolated and identified using biochemical methods. The Kirby–Bauer disk diffusion method was used to assess the response of the bacterial isolates to meropenem. Results showed that out of 82 P. aeruginosa infection cases. The percentage of isolates resistant to meropenem was 62.19%, sensitive was 34.14%, and those with intermediate response was 3.6%. The highest resistance to meropenem was observed in SSTIs with systemic sepsis. The study concludes that the incidence of P. aeruginosa infection is high, and resistance to meropenem is correlated with the severity of the infection.
 
Prevalence and Antibiotic Susceptibility of Enterococcus faecalis Isolated from Urine Samples of Iraqi Women with Urinary Tract Infections
Get PDFEnterococcus faecalis is one of the most important pathogens associated with urinary tract infections (UTIs) in women. The literature on the incidence of UTI infections caused by E. faecalis in Iraq is limited. The increasing antibiotic resistance of this bacterium is one of the main challenges facing clinicians. This study aims to investigate the prevalence of E. faecalis UTIs in Iraq and to assess the response pattern to three commonly used antibiotics in Iraq: nitrofurantoin, ampicillin, and ceftriaxone. A total of 83 urine samples were collected from women suffering from UTIs. Morphological and biochemical methods were used to identify the isolates, and VITIK II technology was employed to confirm bacterial identification. The microdilution in microtiter plates was used to measure the susceptibility of E. faecalis to the three antibiotics. The results showed that the rate of UTI caused by E. faecalis was moderate, at 12.04%. The resistance to ampicillin was 100%, while resistance to nitrofurantoin was 50%. The response to ceftriaxone was also moderate. In conclusion, the study found that the incidence of UTI with E. faecalis among patients was moderate, and the effectiveness of nitrofurantoin was 50%.
 
Impact of Biofilm Formation on Antibiotic Resistance in Escherichia coli
Get PDFEscherichia coli is a main nonpathogenic bacterium naturally present in the human gut. However, certain strains have adapted to cause infections, leading to illnesses in the gastrointestinal tract, urinary system, or central nervous system, even in otherwise healthy individuals. The study focused on the role of biofilm formation on resistant isolate of E. coli. Biofilms can be defined as groups of microorganisms attached to a surface. In this study 25 strains of E. coli have been used, the isolates have been detected by using Gram-stained, biochemical test and VITEC 2 system, As for antibiotic resistance, six antibiotics have been used, nitrofurantoin, piperacillin, amikacin, ceftriaxone, chloramphenicol, and Vancomycin. The concentrations have been used according to the clinical and Laboratory Standard Institute (CLSI). Biofilm Assay Protocol was used. All isolates exhibited sensitivity to nitrofurantoin and chloramphenicol, but they were resistant to piperacillin (100%), vancomycin (100%), and ceftriaxone (50%), followed by amikacin (50%). Biofilm production of 25 E. coli isolates showed that 25 isolates were able to form a biofilm, 11 isolates indicated a strong reaction, 6 were medium and 8 of them were weak biofilm production. Among isolations creating biofilm more than 44 % of bacteria exhibit strong biofilm production, 24% moderate, and less than 32 % weak biofilm production.