In this work, Pseudomonas aeruginosa was used to produce pyocholin as siderphores compound. This biosynthesis to get this type of siderphorses were performed by force these organisms by some metal ions such as Fe3+, Ni2+, Cd2+, and La3+. The produced siderphoreses were extracted and characterized by FTIR and 1H-NMR. Beside this biosynthesis, the analog siderphorses compound (ethyl (Z)-2-(2-(4-bromobenzylidene) hydrazinyl)-4-methylthiazole-5-carboxylate) was synthesized to study its coordination chemistry with Fe3+, Cd2+, and La2+ by complexation processes. This ligand was synthesized and characterized by FTIR spectroscopy, 1H-NMR spectroscopy, and UV-Vis spectrometry. It was found that the synthesized ligand was a bidentate ligand that was expected geometry as octahedral for the Fe (III) and La (III) complexes while tetrahedral geometry for the Ni (II) and Cd (II) complexes. The importance of the study lies in the creation of compounds capable of mimicking the action of bacterial extracts, which can be applied in several fields including toxic, and heavy metal remediation, iron overload diseases, ẞ thalassemia, iron chelators, anti-malarial, biocontrol agent, and cancer. The synthetic compounds were identified also using IR spectroscopy, 1H-NMR, and UV-Vis spectrometry. This work may contribute to open the door to show the probability using siderphores or their analogues to reduce toxic metals levels, pollutants, and waste of crude oil such as cadmium and mercury in Iraq by microbial organisms.

It is believed that the marine animals contain many compounds that could be beneficial for the treatment of many diseases. In this study, the acetone extract of Stichopus hermanni was fractionated by a liquid chromatography and then fractions were assayed for terpenoids. The fraction C18 that received a positive response for terpenoids was purified further and characterized by the liquid chromatography, mass spectral, and Thin-layer chromatography analysis. A terpenoid compound, squalene, was identified as the constituent of the bioactive extract fraction. Antimicrobial activity of C18-3 was tested against Bacillus subtilis, Bacillus cereus, Pseudomonas aeruginosa, Salmonella typhi, Proteus vulgaris, Escherichia coli, Klebsiella pneumonia, Staphylococcus aureus, and Nocardia brasiliensis pathogens. The lowest MIC and MBC values were observed in the Bacillus cereus (50 µg/mL) and Staphylococcus aureus (500 µg/mL), MIC and MFC the fungal pathogen Candida albicans (400 and 2000 μg/mL) and was cytotoxic against KB/ C152 and HUT-78/C185 cells (IC50 6. 1 μg/mL and 6. 29 μg/mL). This research suggests S. hermanni can be used as an alternative source for the separation and purification of squalene compound as a medicinal supplement.

Pseudomonas aeruginosa (P. aeruginosa) have a considerable risk to public health in the world, due to its high ability to develop resistance to different classes of antibiotics. It has been discovered as a prevalent coinfection pathogen that causes sickness exacerbation in COVID-19 patients. This study aimed to determine the prevalence of P. aeruginosa from COVID-19 patients in Al Diwaniyah province, Iraq and to identify its genetic resistance pattern. 70 clinical samples were obtained from severe cases of patients (RT-PCR positive for SARS-COV-2 on a nasopharyngeal swab) who attended Al Diwaniyah Academic Hospital. 50 P. aeruginosa bacterial isolates were detected via microscopic examination, routine cultured and biochemical testing, then validated by the VITEK-2 compact system. VITEK reported 30 positive results, which later confirmed through molecular detection using 16s RNA specific for detection and a phylogenetic tree. 20 isolates had positive PCR findings and 5 isolates submitted to GenBank with accession numbers OL314557. 1, OL314556. 1, OL314555. 1, OL314554. 1, OL314553. 1. For antibiotic resistance genes, the number of the isolates containing blaOXA-1 and blaCTX-M 18 (90 percent) and 16 (80 percent) respectively. To study its adaptation in a SARS-CoV-2 infected environment, genomic sequencing investigations were undertaken with phenotypic validation. In conclusion, we demonstrate that multidrug resistant P. aeruginosa play an important role in in vivo colonization in COVID-19 patients and could be one of the causes of death of these patients which indicates the great challenge to clinicians in the facing of this serious disease.

One of the main causes of soil pollution is the release of crude oil into the environment. Indigenous microorganisms with the capability of biodegrading hydrocarbon components can be used to improve the efficiency of microbial bioremediation technology. Here, oil-contaminated soils were collected from five oil refineries (Abadan, Isfahan, Tehran, Tabriz and Shiraz) for screening and isolation of geographically adaptive indigenous oil-degrading bacteria. Bacterial colonies from oil-contaminated soil samples were isolated, which were able to grow in a medium containing crude oil, light, and heavy diesel, as a sole carbon source. Twelve strains were isolated, purified, and identified, using the 16S rRNA gene sequencing analysis. The isolates belonged to five species, including Achromobacter spanius, Klebsiella quasipneumoniae, Ochrobactrum intermedium, Citrobacter amalonaticus, Pseudomonas aeruginosa. These bacterial strains were capable of growing in media containing crude oil, light and heavy diesel for 7 to 9 days and had the potential for biosurfactant production. These bacterial strains can be considered as geographically adaptive bacteria, creating preliminary data for further research to utilize their bioremediation potential.

OBJECTIVE: Keffir is known as one of the sour milk products that originated in the north of caucasus.Up to now it hasnt been studied about its antimicrobial and antifungal effects. In general, keffir contains the following microorganisms: Lactic acid streptococci, lactiobacilli-mesophilic lactic acid, lactose fermenting and non-fermenting yeasts and lacetic acid bacteria.The objective of this study was to determine therapeutical effects of keffir. METHODS: This study was performed on bacteria such as stapihylococcus aureus, E. coli, Pseudomonas aeruginosa, salmonella typhi, and three species of fungi: candida albicans , trichophyton mentagrophytes and microsporum canis.The antimicrobial effects of eight extracts of common yoghurt and extract of keffir in the 200c and 370c at two times of 24 and 48 hour fermentation in invitro on four species of bacteria and three species of fungi were studied by cup plate and serial dilution method.FINDINGS: From extracts of common and keffir voghurt in the 20 and 37oc at two times of 24 and 48 hour, keffie had the most effect on p.aeruginosa in the 37oc with 48 hour fermentation time with 75 mg/ml concentration.CONCLUSION: Kerfir have the antimicrobial effect on some of pathogenic bacteria as P. aenuginosa.

Studies describing antagonistic activity and disease resistance efficacy of potential probiotics towards lactococcosis caused by Lactococcus garvieae, Lactococcus lactis, Lactococcus piscium, and Lactococcus raffinolactis are limited. Most studies have focused on lactic acid bacteria (LAB), and less attention has been paid to Bacillus probiotics or other gram-positive or gram-negative members. Lactobacillus, Lactococcus, Leuconostoc, and Enterococcus are the most common genera of LAB tested towards L. garvieae either in in vitro or in vivo assays, and the obtained results are promising. Although strains of Flavobacterium, Pseudomonas, Aeromonas, and Vibrio genera have shown antibacterial activity against L. garvieae, further work is required to confirm such inhibition activity, particularly by disease resistance bioassays. recently, gram-positive or gram-negative bacteria strains have demonstrated antimicrobial inhibition towards L. garvieae in postbiotics, but details of their mode of action warranted further studies. This review addresses the probiotic therapy for lactococcosis in aquaculture and discusses the present gaps.

In recent years, bimetallic nanoparticles have gained prominence in medical science due to their biomedical properties. This research aimed to develop an eco-friendly, simple and facile process to synthesizing green silver nanoparticles (AgNPs) using Trachyspermum ammi fruit extract. The synthesized silver nanoparticles were characterized using FT-IR, UV-Vis spectroscopy, XRD, DLS, and TEM. The minimum inhibitory concentration (MIC) values of the synthesized AgNPs and T. ammi extract for five standard bacteria strains were determined by the broth microdilution method. The obtained AgNPs exhibited Surface Plasmon Resonance centered at approximately 415 nm, with an average particle size calculated to be 50 nm. The mean particle size and surface charge of biosynthesized AgNPs using T. ammi extract investigated by DLS and zeta potential were 26.78±1.24 nm and -13.96 mV, respectively. Furthermore, green synthesized AgNPs showed high and efficient antibacterial activity against E. coli ATCC 25922, P. aeruginosa ATCC 27853, K. pneumonia ATCC 9997, S. aureus ATCC 25923, and E. faecalis ATCC 29212 with MIC values of 19, 19.5, 75, 150, and 39 µg/ml, respectively. Notably, the antibacterial results illustrated that green synthesized AgNPs possess significantly higher antibacterial potency than chemically produced silver nanoparticles. Our findings highlight the effective and efficient synthesis of silver nanoparticles by T. ammi fruit extract and its significant antibacterial activities.   

Introduction: In this study, the chemical composition and antimicrobial activity of essential oil of Ziziphora clinopodiodes and its potential application as a natural preservative in reducing the indigenous microbial population of hamburger were investigated. Method: Essential oil of Ziziphora clinopodiodes cultivated in Iran was obtained by Hydro-distillation method (HDM). Chemical composition of the oil was determined by gas chromatography/mass spectrometry (GC-MS) analysis. Antimicrobial activity of the essential oil was checked against Staphylococcus aureus, Escherichia coli, Bacillus subtilis, Salmonella typhi, Listeria monocytogenes, Pseudomonas aeruginosa, by using Agar dilution method (ADM). Minimum Inhibitory Concentration (MIC) values of each active oil concentration were determined and its potential application as a natural preservative in reducing the indigenous microbial population of hamburger was investigated. Results: The major components were carvacrol (54.31%), thymol (12.51%), octadecane (9.51%) and pulegone (4.88%). The results showed a significant activity against the tested strains (gram-positive and gram-negative bacteria). Addition of essential oil in concentration higher than MIC values reduced the microbial population of hamburgers stored at 25°C, 4°C and -12°C. In samples refrigerated at 4°C, differences between the controls and samples treated with essential oil at MIC values (0.20 and 0.4 mg/ml)  were  not  significant  during the first 24 h (p> 0.05), but higher concentration of essential oil resulted in about 2 to 3 log reduction in total microorganisms. Conclusion: This study showed that the Ziziphora clinopodiodes essential oil can be added to the ingredients of foods as the natural antibacterial agent.

Antibiotic resistance has contrived the use of medicinal plants with fewer side effects instead of common drugs. Garlic has sulfur-containing organic compounds and has broad antimicrobial properties against bacteria, even in the lowest concentrations. Allicin or diallyl disulfide is the main garlic sulfur compound with antimicrobial activity. This research investigated the different impacts of nitrogen (N) and selenium (Se) concentrations on garlic clove antioxidant and antibacterial activity. Three concentrations of Se, such as 0, 5, and 10 mg/l sodium selenate and N, containing 0, 50, 100, and 150 Kg/ha, were examined on garlic's antioxidant and antimicrobial properties. The results showed that the antioxidant activity (66.77%) improved in four nitrogen concentrations. Selenium decreased the allicin content of garlic clove. The highest inhibition of the growth rate was observed in Escherichia coli at 12.00 mm, Pseudomonas aeruginosa at 1.73 mm, Bacillus subtilis at 8.95 mm, and Staphylococcus aureus at 10.90 mm were obtained in 150 kg/ha N coupled with 10 mg/l sodium selenate. The lowest inhibitor of the growth of all four bacteria was observed in the control treatment. According to the results, an increase in antioxidant activity was associated with an increase in the antimicrobial properties of garlic. The use of selenium and nitrogen increased the inhibitory influence of bacterial growth.