Fourty three isolates ( 20.7%) characterized as Staphylococcus aureus , were isolated from 207 different clinical sources (blood , nose, , wound , urine , vaginal, ear and eye) in different percentages (30.23, 18.60, 16.28, 13.95, 15.15, 6.96 and 2.33 %), respectively. The staphyloxanthin (STX) production of S. aureus isolate was estimated 72.1% .The optimal conditions for pigment production by S. aureus AE36 , were detected and was noticed that the milk agar medium revealed the highest production of pigment which was estimated to be 165.21unit/cell, at pH 8 for 72 hr at 370C. The Staphyloxanthin pigment was extracted using methanol and was purified partially by organic solvents and Thin Layer Chromatography (TLC). The results revealed three peaks with a highest peak at 450 nm .No antibacterial activity of STX was detected against the bacteria used in this study (Staphylococcus epidermidis, Pseudomonas aeruginosa, Salmonella spp., Shigella spp., Escherichia coli, Klebsiella spp , Proteus spp. Pseudomonas fluorescens , Pseudomonas putida , Staphylococcus aureus).
The microbial production of substances that have the ability to inhibit the growth of other microorganisms is possibly the most common defense strategy developed in nature. Microorganisms produce a variable collection of microbial defense systems, which include antibiotics, metabolic by-products, lytic agents, bacteriocins and others. The aim of the present study was to isolate and identify Enterococcus spp. and its most prevalent species from food samples and determine its antibacterial activity against Staphylococcus aureus isolates. A total of 50 food samples from different sources (dairy products (20 samples) and vegetables and fish (15 samples each)) were collected from different local markets in Baghdad and
... Show MoreThe inhibitory effect of Eucalyptus rostrata leaves extraction was investigated on multiple-antibiotic-resistant pathogenic bacteria (E.coli and S. aureus), isolated from Iraqi patients. The minimum inhibitory concentrations in a final concentration of 10 mg/ml. Tow fold dilutions was done from (12.5- 100) mg/ ml to examine the antibacterial effect of different concentrations of the plant extract on both bacteria. The study results revealed that Eucalyptus rostrata extract has a potential inhibitory effect on both gram negative and gram positive species. The current study supports the traditional approach of using Eucalyptus rostrata leaves extraction in treatment trails against bacterial infections.
A total of nine swab samples were collected from inflamed teeth and gingiva of human’soral cavity from a dentist clinic in Baghdad. All specimens were cultured in Mitis Salivarius agar medium and the isolated bacterial pure colonies werethen identified by using VITEK2. Three samples were diagnosed and identified as Staphylococcus lentus. One of the three isolates which showed a distinctive heavy growth on the media was selected for further analysis in this study. Paper disk diffusion method was used to detect the antibacterial activityof three of mouthwash solutions (Zak, Colgate and Listerine). The results showed that “Colgate†was the most active solution with antibacterial activity compared with the other two soluti
... Show MoreAbstract A total of 207 specimens were collected from different sources including patients, health care staff and hospital environment in Ibb city, Yemen. The study used the bacteriocin produced from active producer strains in typing of Staphylococcus aureus. Depending on the morphological, cultural and biochemical characteristics, 54 (26.09%) isolates of Staphylococcus aureus were identified. An antibiotic sensitivity test was done for the bacterial isolates, and the results showed that there were multiple resistant antibiotics. The Staphylococcin production of these isolates has been detected by using wells assay. Fifty one isolates were Staphylococcin producer. Four isolates (staph19, staph25, staph28 and staph43) were chosen as go
... Show MoreIntroduction and Aim: Bacteriocins are antimicrobial peptides that have bactericidal and/or bacteriostatic activity against other bacteria. The aim of this study was to assess the antibacterial efficiency of Klebocin a K. pneumoniae bacteriocin, against biofilm formation by clinical isolates of methicillin resistant Staphylococcus aureus MRSA. Materials and Methods: S. aureus isolated from clinical samples was identified according to vitek 2 system Antibiotic susceptibility test was performed according to disc diffusion method. Vitek 2 compact system was also used to detect MRSA strains. Agar well diffusion method was used to evaluate the antibacterial activity of klebocin from K. pneumoniae towards 11 strains of S. aureus by
... Show MoreThe increasing use of antiseptic compounds creates selective pressure cause emergence of antiseptic resistance among Staphylococcus aureus .Resistance mechanism of antiseptic is driven mainly by multi drug resistant (MDR) efflux protein.Sixty five isolates of S.aureuswere collected from different clinical sources and subjected to 11 antibiotics most of them are recognized by efflux systems as extruded substrates. Range of efflux activity was estimated using cartwheel method. Simultaneous discrimination of antiseptic coding genes (qacA/B, smr and norA)as well as nuc and mecA genes among multidrug resistantS.aureus(MRSA) isolates was preformed using multiplex PCR assay
... Show MoreRosemary is a well-known aromatic and medicinal plant used to treat various ailments. This study evaluated Rosmarinus officinalis essential oil for its phytochemical and antibacterial properties. The essential oil was analysed by using a gas chromatography-mass Spectrometry (GC-MS) that revealed the common chemicals containing verbenone 36.20% and 1,8-cineol (Eucalyptol) 12.14%. Extracted essential oils were tested for antibacterial activity against vancomycin intermediate Staphylococcus aureus (VISA), a strain of bacteria obtained locally from bacteremia patients. Three isolates were found to be VISA positive using the E-test (strips) and the population analysis profile method (PAP). VISA showed lower resist
... Show MoreLactiplantibacillus plantarum, one of lactic acid bacteria (LAB), is found in various foods, including dairy products, meat, and vegetables, and most of these bacteria offer beneficial effects to humans and animals as potential probiotics with broad-spectrum antimicrobial activities. The aim of this study was evaluating the antibacterial efficacy of L. plantarum against some foodborne bacteria isolated from dairy products. This research involved 34 dairy products, including local and imported milk, cheese, and yogurt sold locally in Baghdad province, Iraq, during May 2022. For the isolation of L. plantarum, a special medium called MRS (de Man Rogosa and Sharpe) was applied. Colonie
... Show MoreStaphylococcus aureus, which includes the methicillin-resistant S. aureus (MRSA), is a significant human pathogen producing different toxins and results in many different infection types, which include bacteremia, soft-tissue infections, as well as staphylococcal food poisoning. S. aureus is an important food-borne pathogen of humans due to ingestion of food containing enterotoxigenic strains. Detecting S. aureus femA and mecA genes was evaluated with the use of a Loop-mediated Isothermal Amplification Method (LAMP). The accuracy of this approach was similar to that attained using the approach of the conventional polymerase chain (PCR). Those two methods characterized 43 isolates of MRSA which
... Show MoreProbiotic bacteria using in commercially produced foods are at most members of the genera Lactobacillus and Bifidobacterium. This research was aimed to study the antimicrobial effect of lactobacillus bacteria as probiotic against some pathogenic bacteria, strains of lactobacillus bacteria were isolated from two types of yoghurt in Baquba city, Iraq . Total of 60 yoghurt samples from 2 origins (30 locally and 30 commercial produced yoghurt) were used to isolate probiotic bacteria which were identified phenotypically and biochemically. 30 (100%) of locally produced yoghurt samples include with probiotic bacteria while 12 (40%) commercially types of yoghurt samples were contained with probiotic, the method of modi
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