Diatoms are considered a potentially new and valuable source of biologically active compounds including those with antimicrobial properties; so, this study was conducted to evaluate the antibacterial activity of Navicula incerta. The diatom was isolated from the salt water of Sawa Lake, southern of Iraq, it was cultivated in salt water then was adapted and cultivated in freshwater environment; the harvested and dried biomass was extracted, and the antibacterial activity of each extract was evaluated against several species of pathogenic bacteria. The chemical constituents of the extracts were also analyzed using Gas chromatography/Mass spectrometry technique. Generally, the result showed that fresh water extract of N. incerta has higher antibacterial activity than salt water extract; Furthermore, the diatom extract inhibited the growth of Staphylococcus aureus strain that was resistant to five different antibiotics; moreover, the chemical constituents of N. incerta in salt water were different from the same diatom when cultivated in fresh water.
In recent years, infectious diseases are increasingly being encountered in clinical settings. Due to the development of antibiotic resistance and the outbreak of these diseases caused by resistant pathogenic bacteria, the pharmaceutical companies and the researchers are now searching for new unconventional antibacterial agents. Recently, in this field, the application of nanoparticles is an emerging area of nanoscience and nanotechnology. For this reason, nanotechnology has a great deal of attention from the scientific community and may provide solutions to technological and environmental challenges. A common feature that these nanoparticles exhibit their antimicrobial behavior against pathogenic bacteria. In this report, we evaluate
... Show MoreSilver nanoparticles synthesized from aqueoes extract for mushroom pleurotus ostreatus. Silver nanoparticles were showing good antibacterial activity. The antibacterial activity conducted against different pathogenic bacteria such as Serratia marcescens, Pseudomonas fluorescens, Listeria, Methicillin-resistant Staphylococcus aureus (MARSA), Proteus mirabilis, Proteus vulgaris and Klebsiella pneumoniae. The maximum inhibition zone was observed against S. marcesance. However, the lowest inhibition zone was found against P. fluorescens.
Honey is one of the most products has been used as an antimicrobial agent since the ancient times. The potential antimicrobial activity of honey is arise from its physiochemical proprieties such as high osmotic pressure, low pH, in addition to other factors and enzymes that work as antimicrobial agents. All these components and characteristics of honey led to consider it as one of the most efficient, useful and natural antimicrobial agents. From this point of view, recent study aim to evaluate the antibacterial activity of bee honey on some common species of pathogenic bacteria. The study included some of both gram-positive (Staphylococcus aureus, Staphylococcus epidermidis and Streptococcus spp.)
... Show MoreAbstract Background: Multidrug-resistant bacteria (MDR) often contaminate hospital environment and cause serious illnesses. Quorum Sensing (QS) regulates a variety of downstream cellular processes, including antibiotics resistance mechanisms and biofilm formation, and causes harm to the host. This study investigates antibacterial susceptibility and biofilm formation of pathogenic bacteria in hospital environment. Methods: Hundred bacterial isolates were collected from various environments in the Medical City hospital. The antimicrobial susceptibility technique was evaluated through disk diffusion method. Next, biofilms formation was detected by the microliter plate assay. Finally, PCR was used to analyze the frequency of QS system gene
... Show MoreIn the current study, three types of algae namely Tetradesmus nygaardi (MZ801740), Scenedesmus quadricauda (MZ801741) and Coelastrella sp (MZ801742) were extracted by 95% ethanol and hexane against two types of gram positive and two types of gram negative bacteria by wells diffusion methods. Eleven concentrations from the extract of algae (2, 5, 10, 15, 20, 25, 30, 35, 40, 45 and 50 mg/ml) were utilized. It was noticed that ethanolic extraction was more effective than hexane in Scenedesmus quadricauda than the two other mentioned algal species against all pathogenic bacteria, Acintobacter baumanii (ATCC: 19606), Klebsiella pneumonia (ATCC: 13883) Enterococcus faecalis (ATCC: 29212) and Staphylococc
... Show MoreAntibiotic resistance increment is a major problem for the human society nowadays which encourages the efforts to look for new therapeutic alternatives from natural defenses. Synergistic antibacterial activity of epidermin and staphylolysin LasA A against Staphylococcus aureus (Staph aureus), Escherichia coli (E. coli) and Pseudomonas aeruginosa (Ps. aeruginosa) was evaluated. The antibacterial activities of epidermin from Staphylococcus epidermidis (Staph epidermidis) and Staphylolysin (LasA) from Ps. aeruginosa using the agar well diffusion assay were evaluated, and then using the micro dilution method to evaluate the minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC). The checkerboard method and fract
... Show MoreThe aim of present study is to investigate the antagonistic activity of Spirogyra micropunctata against multidrug resistant human pathogens. The test organisms include 3 Gram negative bacteria such as Echerichia coli, Klebsiella pneumoniae, Salmonella typhi and 2 Gram positive bacteria such as Staphylococcus aureus and Staphylococcus epidermidis. The algal cell mass was extracted in 90% Methanol and 90% Ethanol and further concentrations of 0.5, 1, 3, 5, 10, 20 mg/ml were made for each extract. Antagonistic effect was tested by using agar well-diffusion method. Methanolic crude extract showed strong antibacterial activity against all tested bacteria, while ethanolic crude extract showed moderate activity. These findings suggest the possi
... Show MoreAntibacterial activity of CNSs against Staphylococcus aureus and Escherichia coli was estimated. Higher inhibition zone of 18 mm and 20 mm were observed against S. aureus and E.coli, respectively, at a concentration of 2 mg/ml of carbon nanosphere after 24 hrs of incubation at 37 ºC. In vitro cytotoxicity experiment was performed on two parasite strains of Leishmania donovani and Leishmania tropica by using MTT assay. L. donovani revealed more sensitiv to the CNSs than L. tropica. An intermediate level of cytotoxicity of 51.31 % was observed when 2.4 mg/ml of CNSs was incubated with L. donovani, while weak cytotoxicity of 37.20 % was shown when the
... Show MoreNosocomial infection is acquired contamination of hospitals and health care units caused by multidrug resistant bacteria. Currently, bacterial resistance to antimicrobial medication represents a complicated public health problem. Recent studies on the antimicrobial activity of silver nanoparticles (AgNPs) attracted researchers worldwide to focus on the safe synthesis of AgNPs as antimicrobial agents against multidrug resistant bacteria. The antimicrobial efficacy of AgNPs on pathogenic bacteria isolated from clinical cases of acquired hospital infection was targeted in this project. Fifty specimens of stool were collected through private laboratories in Baghdad from patients who suffered diarrheal symptoms. Bacterial isolation, identific
... Show MoreAn increasing trend to use probiotic and study their effects on the pathogens has been conductor where they are defined as live micro-organisms that give a health benefit to the host when ingested in sufficient quantities, including the yeast Saccharomyces boulardii In addition research show that a magnetic field (MF) has a biological effect. This study aims to investigate the effects of magnetic field on the inhibitory action of Saccharomyces boulardii against bacteria isolated from urinary tract infection, Study the sensitivity of bacterial isolates to antibiotics after diagnosis by microscopic, Cultural and biochemical examinations as well as Api20 E examinations were used gram negative bacteria , Most isolates were resistant to an
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