Background:The extended-spectrum beta-lactamase (ESBL) -producing Escherichia coli isolates make many serious infections, especially urinary tract infections.Objectives:The purpose of this study was to determine the antibacterial activities of some natural plant extracts against ESBL-producing E. coli isolates, which harbor the TEM gene in urine samples of the patients who have urinary tract infections.Materials and Methods:Evaluation has to be exactly determined for both methods of disk diffusion test and polymerase chain reaction (PCR), separately. We evaluated 120 strains of E. coli isolates from the urine culture of the patients in Boo-Ali Hospital (Zahedan, south-eastern Iran) who were suffering from urinary tract infections. The ESBL-producing E. coli isolates were evaluated by disk diffusion test and PCR through TEM gene detection. The minimal inhibitory concentration (MIC) of commonly used antibiotics including ceftazidime, ceftriaxon, amikacin, gentamicin and ciprofloxacin along with the MIC of the alcoholic extract of different natural plants including Myrtus communis L (Myrtaceae), Amaranthus retraflexus (Amaranthaceae), Cyminum cuminum L (Apiaceae), Marrubium vulgare (Laminaceae) and Peganum. harmala (Zygrophyllaceae) against the ESBL-producing E. coli isolates, which harbor the TEM genes, were determined using the microdulition method.Results:Results of this study showed that in disk diffusion method, 80 samples of E. coli produced ESBLs. In PCR method, the TEM gene distribution in the isolated ESBL-producing organisms was 50 (41.6%). Amikacin was the most effective anti-bacterial agent and ciprofloxacin was the least effective against E. coli isolates. All the natural plant extracts mentioned above, especially P. harmala, were effective against the selected isolates of ESBL-producing E. coli. The most frequent ESBL rate producing E. coli isolates (32 out of 50) had MIC of 2.5 mg/mL in ethanol extract of P. harmala.Conclusions:The alcoholic extract of P. harmala was very effective against the selected ESBL-producing E. coli isolates harboring the TEM gene. Therefore, it could be suggested as an antibacterial agent in the future. More researches are necessary for detecting the mechanism of this plant’s behavior and its pharmacological effects.

In conclusion, it seems that Z. multiflora and M. longifolia extracts could inhibit the growth of all of the mentioned bacteria.

Background:Trachyspermum ammi or Carum copticum, commonly known as Ajowan or Ajwain is a plant used as a spice. Thymol, the major phenolic compound present in Ajowan is known as a strong germicide and anti-spasmodic. It is also used for cleaning the wounds and treating skin infections. Objectives: Here, we aimed to study the inhibitory effects of Ajowan essential oil on microorganisms like Escherichia coli (E. coli), Klebsiella, and Staphylococcus aureus growth. Material and Methods: Antibacterial activities of Ajowan essential oil (AEO) have been evaluated against two gram negative bacteria; Klebsiella and E. coli and one gram positive bacteria; Staphylococcus aureus (S. aureus). Minimum inhibitory concentration (MIC) value was determined against all mentioned bacteria. Results: The antibacterial activity of AEO was assessed against all selected pathogens and different MIC levels were observed. The essential oil was effective for S. aureus with MIC of 1.25 mg/mL, followed by, E. coli with MIC of 2.5 mg/mL and Klebsiella with MIC of 5 mg/mL. Conclusions:The results of the present study showed that the AEO has antibacterial effects against human pathogens that are resistant to antibiotics. More studies should be performed to demonstrate the detailed mechanism of this antimicrobial effect.

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Background: Development of antibiotic resistance among pathogenic bacteria motivates the researchers to search for newer antimicrobial agents. Objectives: In the present study, antibacterial effects of Cuminum cyminum Linn. essential oil against multidrug resistant (MDR) Escherichia coli strains isolated from urinary tract infections were studied, using microdilution method. Materials and Methods:: A total of 12 E. coli strains were isolated from urine cultures of hospitalized patients (Zabol, southeastern Iran) suffering from urinary tract infection during 2011-2012. After bacteriological confirmatory tests, minimum inhibitory concentrations (MICs) of the essential oil of C. cyminum Linn. were determined using microdilution method. Essential oil of C. cyminum Linn. was obtained by hydro-distillation and the MICs were investigated to characterize the oil antimicrobial activities. Results: All of E. coli isolates were resistant to four of the antibiotics including ceftazidime (50%), cefixime (41.6%), tetracycline (75%) and erythromycin (58.3%). The highest MIC value (250 ppm) was observed against two antibiotics and the lowest (10 ppm) against one antibiotic. Conclusions: C. cyminum Linn essential oil has a potent antimicrobial activity against E. coli MDR strains. Our study confirms the use of this essential oil as an antibacterial agent. However, further research will be required before its therapeutic application.

Background: Emergence of bacterial resistance is critically an alarming situation in the health care industries. The medicinal plants have been used in the folk medicine to treat diseases without knowing their active compounds. Objectives: The aim of present study was to screening the antibacterial activities of Withania somnifera leaf extract against antibiotic resistant strains of Staphylococcus aureus. Patients and Methods:In this cross-sectional study, a total of 17 strains of S. aureus were isolated from hospitalized patients (Boo-Ali, Nabi-Akram and Imam-Ali hospitals, Zahedan, South-Eastern Iran) suffering from urinary tract infections during the years 2011 -2012. The extract of W. somnifera obtained by rotary and the minimum inhibitory concentrations were investigated to characterize the antimicrobial activities of this extract. Results: Overall, S. aureus showed resistance to 6 antibiotics including oxacillin (83.3%), ceftazidime (66.6%), penicillin (50%), trimethoprimsulfamethoxazol (41.6%), cefixime (33.3%) and vancomycin (8.3%). The highest minimum inhibitory concentrations (MIC) values of extract were found to be 250 ppm against 12 strains and the least value was 63 ppm against 2 strains. Conclusions: Ethanol extract of W. somnifera leaf might be exploited as natural drug for the treatment of several infectious diseases caused by this pathogen.

Background: Scientists are seeking an appropriate alternative method for curing infections caused by resistant bacteria, since drug resistance is continually increasing. Objectives: This research aims to discover the function of some medicine plants on pestiferous Pseudomonas aeruginosa and Escherichia coli in humans. Materials and Methods: Bacterial strains were obtained from a standard laboratory. The strains of Pseudomonas aeruginosa ATCC27853 and E.coli ATCC25922 bacteria were used for antimicrobial testing of the extractions. Results: Our results showed that Teucrium polium extracts have the minimum density of inhibitory for Escherichia coli, 25 ppm, whereas the maximum of this is for Peganum harmala and Prangos ferulaceae with 100 ppm. The lowest minimum concentration inhibitory value of extracts P. harmala, T. polium, T. pratensis and Rumex was found in 25 ppm against P.aeruginosa. Conclusions:The results of our study showed that plant extracts have good antibacterial properties against Pseudomonas aeruginosa and Escherichia coli.

Background: Many efforts have been made by researchers to find new antibiotics which are clinically useful against bacteria and drug resistant microorganisms. Objectives: We aimed to evaluate the antimicrobial effects of hydroalcoholic extracts of leaves and seeds of the Portulaca oleracea plant in traditional medicine of Sistan region, southeast of Iran. Materials and Methods:In this cross-sectional and descriptive study, from January 2010 to January 2012, we studied the antibacterial activity of P. oleracea extract using nine bacteria (Gram-positive and Gram-negative bacterial strains) which were resistant to standard antibiotics such as erythromycin, cefixime, ceftazidime, tetracycline, ampicillin and amikacin. Bacterial strains were obtained from a standard laboratory. Broth microdilution method was used to determine the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC). Results: The hydroalcoholic extract of P. oleracea L. leave and seed had antibacterial effects on selected drug resistant bacterial strains. Conclusions:The leaves and seeds extract of P. oleracea has a remarkable antibacterial effect and it can be a good alternative when we are faced with drug resistance bacteria. However, more studies are required.