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Background and Objective: Uropathogenic strains of Escherichia coli (UPEC) are the most common cause of urinary tract infections. UPEC strains possess an arsenal of virulence factors including fimH, iucD, iroN and hlyA which increase their ability to cause urinary tract infections. This study was done to determine the relationship between phylogenetic group and distribution of virulence genes of Escherichia coli isolated from patients with urinary tract infection. Methods: This descriptive - analytic study was performed on 100 isolates Escherichia coli which collected from patients with UTIs. DNA was extracted from all isolates by the boiling method and subsequently DNA was used to determine the presence of genes encoding virulence factors by Multiplex-PCR. In addition, determination of phylogenetic group, A, B1, B2 and D, was performed by determination of present or absent of of yjaA and chuA genes and DNA fragment TSPE4.C2 using Triple-PCR. Results: The frequency of virulence factors, fimH, iucD, iroN and hlyA were 95%, 69%, 29% and 32%, respectively. In all isolates, the frequency of phylogeny of groups A, B1, B2 and D were 17%, 6%, 55% and 22%, respectively. A significant correlation was found between the presence of virulence encoding genes and the B2 phylogenetic group (P<0.05). Conclusion: Virulence genes were common in phylogenetic group B2 isolates among all phylogenetic groups.

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Background and Objective: Enterotoxigenic Escherichia coli (ETEC) are the most common agent which causes diarrhea, worldwide. ETEC is colonized along the cells and then producing heat-labile (LT) and heat-stable enterotoxigenic which enter into intestinal epithelial cells and causes water and electrolyte loss from intestinal epithelial cells and eventually cause diarrhea.This study was done to detect the heat-labile toxin in Enterotoxigenic Escherichia coli using PCR-ELISA technique. Methods: In this descriptive study, DIG-labeled PCR products were bounded to streptoavidin-coated wells of a microtiter plate and detected by anti-DIG–peroxidase conjugate. The biotin-labeled internal probe was used for verification of PCR products. Results: Heat-labile toxin was detected by PCR-ELISA method. The sensitivity of heat-labile toxin was 1.9 ng. This method did not cross-react with bacteria from this variety. Conclusion: PCR-ELISA method is 100 times more sensitive than conventional PCR method and due to lack of agarose gel and electrophoresis device it can be a good alternative to traditional method.

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Background and Objective: Mycoplasma pneumoniae bacteria, is one of the most important factor in causing of respiratory infections. Serological and molecular detection methods have their own limitation. Due to this limitation, the application of these methods in all diagnostic laboratories is not possible. Therefore this study was done to determine the rapid detection of Mycoplasma pneumonia by loop mediated isothermal amplification (LAMP). Methods: In this descriptive laboratory study, nasopharynx samples were collected from 92 patients with atypical pneumonia. DNA sample were extracted by boiling method. Six specific primer pairs were designed for LAMP technique by primer explorer ver 4 software. LAMP product identified by adding SYBR Green. Limit of detection and specificity tests have been done for optimizing LAMP test and optimized test carry out for each sample. Results: The LAMP test was optimized using the large Bst enzyme fragment at 66 degree temperature for 1 hour. The detection limit of the test obtained 1 CFU and the DNA replication does not observed in non of the examined pathogenic factors. Out of 92 clinical samples using LAMP technique, 73 cases were negative (80%) and 19 cases were positive (20%). Conclusion: The loop-mediated isothermal amplification technique is simple, convenient and available method for detection of Mycoplasma pneumoniae.

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Background and Objective: Probiotics are beneficial organisms therapeutic within microbial flora. Shigella, Escherichia coli and Salmonella are the most common cause of intestinal infectious diseases that lead to morbidity and mortality in infant and children worldwide. The aim of this study was to evaluate anti-microbial activity of Lactobacillus acidophillus and Lactobacillus ruteri against entero-pathoges by in vitro and in vivo methods. Methods: In this experimental study, the therapeutic effect of the lactobacillus acidophilus ATCC 4356 and ruteri ATCC 23272 against Shigella sonnei ATCC 9290, Escherichia coli ATCC 25922 and Salmonella enterica BAA-708 were evaluated by in vitro (spot agar) and in vivo (BALB/c mice) methods. Weight improvment and survival rate in mice were recorded. Results: Lactobacillus acidophillus and ruteri had protective and therapeutic effect against diarrhea caused by pathogenic bacteria. Probiotics reduced the weight, colonization of pathogens and increased the survival rate of animals (P<0.05). Conclusion: Lactobacillus acidophillus and ruteri has anti-microbial activity and their consumption can be effective in the prevention and also the treatment of intestinal disease.

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Background and Objective: Mycoplasma Hominis is the smallest pathogenic bacteria, with no cell wall and free living organisms. It grows slowly and the conventional clinical microbiology techniques can not be applied due to difficulties in cultivation in particular slow growth incubation. This study was done to compare the culture and PCR methods for diagnosis of vaginal infection due to Mycoplasma Hominis. Methods: This laboratory test evaluation study was done on 150 patients with bacterial vaginosis and 50 healthy people with no infection as control, whom refereed to Imam Khomeini and Imam Zaman Hospitals in Tehran. Samples were collected in PPLO culture for growth and PBS to perform PCR method. Results: 35.3% and 76% of patients were positive using culture and PCR methods, respectively. Using PCR method 8% of control subjects was positive. There was no significant association between PCR method with abortion, place of residence and also level of educations. There was a significant association between the age (P<0.05), times of changing under wear cloths (P<0.05) and parity (P<0.05). Conclusion: PCR method is a more reliable technique to detect the vaginal infection due to Mycoplasma Hominis compared to culturing.

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Background and Objective: Wound infection treatment, particularly in chronic and bacterial poly cases, is difficult and entails heavy costs. This study was done to determine the prevalence of poly bacterial infection and antimicrobial susceptibility of wound samples from different wards. Methods: In this descriptive study, wound sampling was prepared from 336 patients admitted to different wards of Baqiatallah Hospital in Tehran, Iran. Identification was performed based on biochemical tests including oxidase test, TSI, IMVIC, lysine decarboxylase, phenylalanine deaminase, urea, motility, catalase, coagulase, mannitol fermentation, optochin sensitivity, susceptibility to bacitracin and sulfamethoxazole, growth in Bile esculin and DNase production. Antibiotic resistance pattern of isolates was determined using disk diffusion method for 14 important antibiotics. Results: 294 samples were positive for bacterial culture, from which 364 isolates including 11 different isolates were obtained. Out of 294 positive samples, 245 samples were mono bacterial and 54 were poly bacterial including two-bacterial (45 samples), three-bacterial (7 samples), and four-bacteral (2 samples). S. aureus (29.7%), Enterococci (15.6%), and E. coli (15.6%) were the most prevalent isolates. S. aureus-Enterococci pattern was the most common two-bacterial pattern (33%), and majority of polybacterial patterns belonging to gram negative bacteria was in surgery ward (32.5%). Antibiogram results showed high levels of antibiotic resistance in the isolates. Imipenem and amikacin were the most effective antibiotics against Gram negative isolates, and vancomycin for Gram positive isolates. Also, 71% of S. aureus isolates were resistant to oxacillin. Conclusion: Variation of bacterial isolates was similar to other studies. Most of poly-bacterial wound infections were due to common nosocomial pathogens and their high rates of antibiotic resistance are extremely alarming.

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Background and Objective: Resistance of Staphylococcus aureus to antibiotics is one of the major global health problems in human societies. Thus, evaluation of pattern of antibiotic resistance in its different strains is very important. This study was carried out to evaluate the antibiotic resistance in Staphylococcus aureus isolated from clinical samples by disk diffusion and PCR methods.

Methods: In this laboratory- descriptive study, 50 isolates of Staphylococcus aureus to be identified from clinical specimens. Methicillin resistance was examined using PCR and antibiotic susceptibility of isolates was tested by disk diffusion method.

Results: 50 isolates were resistant to methicillin, ampicillin and penicillin. The resistance of isolates to erythromycin, Gentamicin, Clindamycin and Ciprofloxacin were 48%, 34%, 34%, 34%, respectively. The PCR method showed that 98% of Methicillin Resistance of Staphylococcus aureus isolates carried the methicillin resistant gene.

Conclusion: This study indicated that 98% isolates harbor mecA genes and more resistant to methicillin related mecA genes.

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Background and Objective: Yersinia is a gram-negative bacillus that cause diarrhea through consumption of contaminated food and water.  This study was performed to identify the atypical Yersinia virulence markers isolated from children with diarrhea.

Methods: This descriptive cross -sectional study was done on 384 fecal samples of 0- 14 years old children admitted at children medical center from August 2011 to August of 2012. Fecal samples, for the enrichment, after 21 days of incubation in alkaline buffer with pH=7.2 at 4degree C, on days 7, 14 and 21 samples were cultured on CIN agar and Mac agar and then confirm the differentiation atypical Yersinia from other typical Yersinia species from fermentation of different sugars. Isolates were tested for marker of virulence including calcium dependence, auto agglutination, Congo red uptake and binding of crystal violet.

Results: Out of 384 stool samples, 4 (1.04%) were infected with Yersinia (Yersinia frederikseni, Yersinia kristensenii and Yersinia enterocolitica). Out of these three, only two samples in association was positive with virulence markers.

Conclusion: Phenotypic markers can be used to study the properties of phenotypic strains of Yersinia.

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Background and Objective: The rise of antibiotic resistance particulary Methicillin resistance in pathogenic bacteria such as Staphylococcus aureus is found to be an emerging threat to human health especially in hospitals. Heavy metal nanoparticles such as Ag used for inhibition of this bacterium. This study was done to determine of minimum inhibitory concentration (MIC) Ag nanoparticle against Staphylococcus aureus which isolated in Gorgan, north of Iran and its relation with Methicillin resistance and source of bacteria.

Methods: In this descriptive – analytical study, the MIC Ag nanoparticle in 183 isolates of Staphylococcus aureus by microdilution method was determined. 30 isolates, based on mecA gene was considered as MRSA. Samples were collected from patients, nose of healthy carriers and foods. Compare the MIC of isolates based on Methicillin resistance, source of the bacteria and resistance to other antibiotics were assessed.

Results: Out of 183 samples MIC was varied from 1 to 16 µg/ml, and mean±std was 2.9±1.89 µg/ml. MIC mean of silver nanoparticles in isolated from foods were 2±0.7, isolared from healthy carriers were 4.1±2.4 and from patients were 3.4±2.1 µg/ml and were statically significant (P<0.05). MIC mean of silver nanoparticles in MSSA isolates are 3.9±2.3 and in MRSA isolates are 2.4±1.4 µg/ml that were statically significant (P<0.05). MIC mean of gentamycin resistant isolate were lower than sensitive one. But between MIC of silver nanoparticles and other antibiotics resistance was not significant statistically.

Conclusion: There is a relation between silver nanoparticle MIC, source of sample isolation, Methicillin and gentamycin resistance. Since MIC of silver nanoparticles on isolates of Methicillin resistant is low, the possibility of its use in the control of MRSA in hospital infections can be considered as a prime attention the Gentamycine.

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Background and Objective: Probiotc bacteria have benefical effect on consumer health. This study was done to investigate the antimicrobial effect of several probiotic in combinations with different prebiotics against food patoghenic bacteria including Staphylococcus aureus and Listeria monocytogenes.

Methods: In this descriptive - analytical study, probiotics including Lactobacillus plantarum, L. acidophilus, L. fermntum, L. casei and L. rhamnosus with prebiotics (1%) including raffinose, lactulose, inulin and trehalose were cultured in MRS broth for 24 hours at 30ºC in anaerobic conditions. Antimicrobial property of them was determined with well diffusion plate's method.

Results: Probiotics in the presence of prebiotics indicated the higher antimicrobial effect compared to probiotics alone (P<0.05). The application of prebiotics such as L. casei with raffinose showed higher antimicrobial property against Listeria monocytogenes than the free prebiotics consumption. The diameter of inhibitory growth zone in the presence of raffinose as a prebiotics was 14.66 mm and its absence reduced to 11.75 mm.

Conclusion: Antimicrobial effect of probiotics in combination with prebiotics against Staphylococcus aureus and Listeria monocytogenes was higher than probiotics consumption alone.

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Background and Objective: Iran remains a major stronghold for glanders in the Middle East. In Iran, the non-indigenous Burkholderia mallei Razi 325 strain is used in manufacturing of the mallein, required for malleination of animals. Multi Locus Variable number tandem repeat analysis is currently the standard globally accepted genotyping system for Burkholderia mallei. This study was done to survey the genomic structure of Burkholderia mallei Razi 325, the strain used for industrial production of Mallein.

Methods: In this descriptive study, a MLVA genotyping system with 4 previously-characterized loci VNTR140, VNTR1367, VNTR2065, VNTR2971 along with two new loci of VNTR24, VNTR41 was used.

Results: Optimization of PCRs resulted in a single protocol that enabled simultaneous amplification of all the six loci. Sequencing of PCR products revealed there were 2, 3, 12, 6, 1 and 2 copies of the unit repeat hold in the genome of the Burkholderia mallei Razi 325 strain. This observation was extended to include the already-whole genome sequenced Chinese Burkholderia mallei ATCC 23344 and Burkholderia mallei BMQ and also Burkholderia mallei SAVP1 strains.

Conclusion: The Burkholderia mallei Razi 325 strain is distinguishable from the other three strains through MLVA genotyping method.

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Background and Objective: Extended-Spectrum Beta Lactamase enzymes (ESBLs) are the most important factor for antimicrobial resistance in Enterobacteriaceae The resistance to beta-lactam antibiotics is the main problem in the bacterial infections therapy. This study was done to determine the prevalence of Extended-Spectrum Beta Lactamase enzymes in clinical isolates of Enterobacteriaceae family.

Methods: In this descriptive study, 240 isolates of Enterobacteriaceae family were collected from clinical specimens obtained in Shohada, Rahimi and Madani hospitals in Khorramabad city, Iran. Antibiotic susceptibility of isolates was performed by disk diffusion method. ESBLs production in all isolates was determined using the combination disk method.

Results: Bacteria strains isolated in this study were Escherichia coli (76%), Klebsiella pneumonia (16.2%), Citrobacter (5.4%), Enterobacter spp. (0.83%) and Proteus (1.6%). The results of antimicrobial susceptibility of isolates showed that the highest rate of antibiotic resistance was toward Ampicillin (88%) and Cefotaxime (43%) and the lowest rate was observed to Amikacin (2.5%). According to the results of the phenotypic tests, 141(59%) isolates out of 240 Enterobacteriaceae were beta-lactamase producers.

Conclusion: ESBL producer isolates and antibiotic resistant due to of Enterobacteriaceae isolated from clinical samples from hospitals are high prevalence in Khorramabad city, Iran.

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Background and Objective: Beta-lactamase enzymes are the most important resistance factors among Gram-negative bacteria to the beta-lactam group of antibiotics. This study was conducted to determine the prevalence of extended-spectrum beta-lactamases (ESBL) in Escherichia coli isolates using PCR method.

Methods: This descriptive – analytic study was conducted on 120 Escherichia coli samples isolated in hospitals in Sari in northern Iran during 2013. Antibiogram was conducted using combined disk method to determine the sample resistance. The presence of β- lactamase gene of CTX-M-15 in ESBL was assessed using PCR method.

Results: Out of 120 Escherichia coli, 98 (81.6%), 15 (12.5%) and 7 (5.8%) bacteria isolated from urinary tract, blood and wound, respectively. Multiple drug resistance were seen in 98% of urine samples, 12.7% of blood samples and 3.6% of wound samples (P<0.05). 18.3% of multiple drug resistance samples were positive for CTX-M-15 β -lactamases resistance gene. The probable presence of CTX-M-15 were detected in blood sample (20%), urine sample and wounds (14.3%) (P<0.05).

Conclusion: Beta-lactamase enzymes were detected in high percent of Escherichia coli isolated from urine samples.

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Background and Objective: Hypericin is found in different species of Hypericum genus, as a main compound with antimicrobial, antiviral, nonspecific kinas inhibition and dopamin β-hydroxilase inhibitoring effects. This study was done to compare the hypericin content, antioxidant, antimicrobial and cytotoxic activities of Hypericum perforatum L. from three geographic regions of Iran.

Methods: In this descriptive study, Hypericin content of aerial parts of H. perforatum L. was assessed using UV-Vis spectrometric method. Antioxidant activity was measured using DPPH and β-carotene bleaching assay. Cytotoxicity was evaluated via brine shrimp lethality assay. Antimicrobial activity was determined using inhibition zone diameter evaluation via disc diffusion method and measuring minimum inhibitory concentration (MIC) value.

Results: Hypericin content of aerial parts of H. perforatum L. from Qom, Golestan and Kurdestan provinces were 673, 1223 and 1568 ppm, respectively. Antioxidant and cytotoxic activities in samples from Kurdestan was more than samples from Qom and Golestan. Antimicrobial activity, as far as the number of sensitive microorganisms was evaluated. In this way the order of Golestan>Kurdestan>Qom was exhibited, however the extract of the plant from Kurdestan had the highest activity for two staphylococcus species with the inhibition zone diameter of 17 and 19 mm for S. aureus and S.epidermidis, respectively and MIC value of 250 µg/mL.

Conclusion: Hypericin content was more from samples of Kurdistan province with cold climate. Antimicrobial, antioxidant and cytotoxic activities of aerial parts of all samples were high. There is a relationship between hypericin content of aerial parts of H. perforatum L. and biological activities.

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Background and Objective: Enterococci is gram positive bacteria which is the inhabitants of gastrointestinal tract. Hospital infections and antibiotic resistance to enterococci is increased. This study was done to determine the molecular evaluation of vanA and vanB genes of enterococci isolates resistant to Vancomycin and Teicoplanin.

Methods: In this descriptive study, 113 isolates samples were collected and identified according to biochemical test and cultural characteristics in Ali ibn Abi Talib hospital in Zahedan, Iran. Antibiogram test was done to determine antibiotic resistance pattern. E-test strip was used to evaluate the minimum inhibitory of concentration (MIC). PCR was used to detect the vanA and vanB genotype in Vancomycin and Teicoplanin resistance enterococci.

Results: 92%, 6.2% and 1.8% of isolated samles collocted from urine, blood culture and pleura fluid, respectively. According to phenotype, 18.6% and 17.69% were resistance to Vancomycin and Teicoplanin, respectively. Resistance was observed in strains of Enterococcus faecalis and Enterococcus faecium. VanA genotype was seen in all of the resistance isolated species.

Conclusion: This study showed that strains of Enterococcus faecalis and Enterococcus faecium have more antibiotic resistance to the Vancomycin and Teicoplanin, morever vanA genotype precence in all of resistance isolated samples.

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Background and Objective: Pseudomonas aeruginosa is an opportunistic pathogen with numerous virulence factors such as phospholipase and type IV pili. The emergence of multidrug resistant Pseudomonas aeruginosa has become a serious public health threat worldwide. This study was done to determine the frequency of plcH, plcN, pilA and pilB genes in multi-drug resistant Pseudomonas aeruginosa isolated from clinical samples.

Methods: In this cross-sectional study, 93 isolates of Pseudomonas aeruginosa collected from different clinical samples from hospitals of Zanjan, Iran during 2013-14. After identification of isolates by biochemical tests, antibiotic susceptibility testing (Kirby-Bauer) was performed according to CLSI guidelines. Total DNA extracted and PCR was done to detect of plcH, plcN, pilA and pilB genes.

Results: Among 93 of Pseudomonas aeruginosa isolates, the highest antibiotic resistance related to Erythromycin and Cefoxitin (95.6%) and the lowest resistance related to Amikacin (26.8%). 80.6% of isolates were multidrug resistant (MDR). Out of 75 MDR isolates, the frequency of plcH, plcN, pilA and pilB genes was 97.4%, 49.3%, 26.6% and 17.3%, respectively.

Conclusion: According to high frequency of phospholipase C gene (plcH) in MDR Pseudomonas aeruginosa isolates which isolated from different clinical samples, presumably this virulence factor plays an important role in pathogenesis of this bacterium.

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Background and Objective: Nowadays, microorganisms have high resistance to antibiotics due to indiscriminate and unnecessary consumption. Treatment of infections caused by resistant bacteria has become difficult and expensive. Galls wild rose created by wasp's species Diplolepis mayri. This study was done to evaluate antibacterial activity of methanol, acetone and aqueous extracts of Wild Rose gall against Staphylococcus aureus and Enterococcus faecalis.
Methods: In this experimental laboratory study, the methanol, acetone and aqueous extracts of wild rose galls in 15.6, 31.3, 62.5, 125, 250 and 500 mg/dl were prepared by Soxhlet apparatus. Antibacterial activity of extracts was determined using well diffusion. MIC and MBC were determined by microdilution method. The active compounds of gall were evaluated by GC-MS.
Results: The inhibition zone of 500 mg/ml methanol, acetone and aqueous extracts of wild rose gall were 27.3, 26.7 and 20.0, respectively. The inhibition zone of wild rose gall was similar to imipenem (antibiotics). The extract concentration was related with antibacterial activity. The gall rose methanol extract showed the highest antibacterial effect. The MIC and MBC of methanol extract against Staphylococcus aureus and Enterococcus faecalis was 62.5, 31.3 mg/ml, respectively.
Conclusion: This study showed that aqueous, methanol and acetone extracts of wild rose galls have strong antibacterial activity.

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Background and Objective: Mupirocin is a secreted antibiotic inhibitor of Isoleucine-tRNA, a bacterial synthetase that is used against yellow wounds from Streptococcus pyogenic and Staphylococcus aureus. This study was carried out to determine the plasmid resistance of mupirocin in Staphylococcus aureus strains isolated from clinical specimens of the skin of hospital employees and hospitalized patients.
Methods: This descriptive study was performed on 150 strains of Staphylococcus aureus isolated from clinical specimens of the skin of patients and employees of three hospitals in Qom, Iran during
2014-15. In order to confirm the identity of Staphylococcus aureus isolates, conventional biochemical methods were used. Also, PCR of srRNA16 was used for molecular confirmation of isolates. The presence of mupA (iles-2) and mupB plasmid genes was investigated using PCR method and AluI enzyme digestion plan was performed for them. Disc diffusion method was used to demonstrate resistance to mupirocin.
Results: Seven isolated samples (4.66%) were resistant to mupirocin. All Mupirocin-resistant isolates possessed PCR-positive mupacysin mupirocidal genes (iles-2) and mupB, and all plasmid genes were resistant to all resistant specimens. Genotyping of mupB gene was able to isolate samples from patients and staff as well as male and female.
Conclusion: The prevalence of mupirocin-resistant Staphylococcus aureus isolated from skin specimens was low.

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Background and Objective: Salmonella is one of the most important zoonotic pathogens responsible for food-borne infections all over the world. Poultry products are widely acknowledged to be a significant reservoir for Salmonella. This study was done to evaluate the antibiotic resistant of Salmonella enterica producer of beta lactamase spectrum in poultry.
Methods: In this descriptive – laboratort study 70 Salmonella enterica serotypes were collected from poultry. All Salmonella isolates were tested to antimicrobial susceptibility testing by the Kirby-Bauer disk diffusion according to Clinical Laboratory Standards Institute (CLSI). Twenty-nine antibiotics were used in this study. Klebsiella pneumoniae; ATCC 700603 was used as quality control strains. The isolates were determined to be ESBL-producing Salmonella by the conventional double-disk synergy and genotypic method.
Results: Among 70 salmonella isolates, the most prevalent serotypes were S.typhimurium and S.enteritidis. All serotypes were susceptible to gentamicin, ciprofloxacin, oflaxacin, imipenem, enrofloxacin. The common resistance was observed to cephalexin (96%), cefazolin (96%) and cephalotin (65%). Among the 70 Salmonella isolates studied, multi-drug resistance was observed in 59 (84%) isolates. Forty-seven (67%) isolates were found to be ESBL-producing isolates. PCR assay of all isolates showed that 17 isolates (33.3%) carried bala CMY2 gene.
Conclusion: This study showed that antibiotic resistance to Salmonella enterica serotypes is due to beta lactamase enzyme in this strain is considerably increased in poultry.

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Background and Objective: Biofilms caused by pathogenic microorganisms that plays an important role against human health. Due to their resistance to detergents and antimicrobial agent, treatment response of affected patients with these bacteria is difficult. This study was done to evaluate the effect of methanol extract of Nasturtium officinale plant on growth and biofilm formation of Pseudomonas aeruginosa.
Methods: In this descriptive - laboratory study, the extraction was done by Maceration in 80% methanol and by rotary evaporator. The minimum inhibitory concentration (MIC) of Nasturtium officinale extracts were determined by broth microdilution method. Biofilm formation was investigated using the microtiter plate and stained with crystal violet.
Results: The minimum inhibitory concentration of Nasturtium officinale against Pseudomonas aeruginosa was 0.625 mg/ml and the Minimum bactericidal concentration of this extract was 1.25 mg/ml. PAO1 strain and 5 clinical strains were able to biofilm formation. Inhibition of biofilm formation by extract of Nasturtium officinale plant was dependent to concentration. The highest percentage of inhibition of biofilm formation was in the concentration of 7.5 mg/ml and the lowest percentage of inhibition of biofilm formation was in the concentration of 0.11 mg/ml. The mean of Pseudomonas aeruginosa biofilm inhibition by Nasturtium officinale extracts was 72.69±22.27 %. In the concentrations of 7.5, 0.93, 0.46, 0.23 and 0.11 mg/ml, there was a significant difference between clinical strains and PAO1 strain (P<0.05).
Conclusion: Methanolic extracts of Nasturtium officinale plant has anti-bacterial and anti-biofilm effect against Pseudomonas aeruginosa.