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Background:Pneumonia and respiratory tract infections, is associated with high mortality and complications in humans. Current antibiotics are used to treat this infectious disease, but may lead to many problems such as unwanted side effects and resistance to antibiotics. This study investigated the antibacterial activity of the hydro alcoholic extracts of the native medicinal plants Peganum harmala, Mentha pulegium and Alcea rosea, in Baku, as a natural alternative to antibiotics, on antibiotic-resistant Streptococcus pneumoniae and Klebsiella pneumoniae,the main bacteria that cause pneumonia. Materials and Methods: Antibacterial activity of the hydro alcoholic extracts of medicinal part of these plants was evaluated by the disk diffusion susceptibility test method and the broth dilution test method on bacteria. Results: The rate of MIC of P. harmala, M. pulegium and A. rosea extracts of  S. pneumoniae were 80, 110 and 375μgμL^-1  and for K. pneumoniae were 150, 230 and 680μgμL^-1 respectively,  and the rate of MBC were 120, 165 and 550μgμL^-1 for S. pneumoniae and 210, 315 and 800μgμL^-1 forK. pneumonia respectively; The maximum amount of inhibition zone diameter in500μgμL^-1 concentration  ofP. harmala, M. pulegium and A. rosea extracts  for S. pneumoniae were 21.2mm, 17.2mm, 6.9mmand  for  K. pneumonia were10.1mm, 8.1mm, 3.2mm, respectively. Conclusion: This work showed that substances in the hydro-alcoholic extracts of medicinal plants prevented the growth of bacteria. So these plants with having effective ingredients can be used as an affordable and available source for medicinal purposes.

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The use of synthetic antioxidants has reduced due to its harmful effects on consumer health. The present study was conducted to evaluate the antioxidant properties of Mentha pulegium as a source of natural antioxidants. In order to prepare extracts of Mentha pulegium from a methanol solution, a ratio of 5: 1 was used. The levels of tocopherol and phenolic compounds of the extracts were measured by spectrophotometric methods. Finally, methanolic extract of Mentha pulegium at concentrations of 400 ppm and 800 ppm was added to canola oil, and after heating for 24 hours at 180°C, color index, conjugated dienes value, acid value and peroxide value were evaluated to comparison with the sample containing TBHQ. The results showed that extract at concentration of 800ppm has thermal stabilization efficiency comparable to TBHQ(p<0.05). Therefore, Mentha extracts can be recommended as a potent source of natural antioxidants for the stabilization of canola oil or other unsaturated vegetable oils.
 

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In traditional medicine, Mentha pulegium was used for sinusitis treatment, gastrointestinal disorders, respiratory disorders and food detoxity. In this research, Mentha pulegium essential oil (MPEO) antibacterial activity on some foodborne pathogens was considered. For research on MPEO interaction with chloramphenicol and gentamicin antibiotic, sub-minimum inhibitory concentration was used. The results showed that in growth medium MPEO able to control pathogen microorganisms. The inhibition zone diameter (IZD), in disk diffusion method for Listeria innocua, Staphylococus aureus, Escherchia coli, Salmonella typhi, Pseudomonas aeruginosa bacteria was 16/50, 14/60, 10, 14, 10 mm respectively. The mean of IZD in well diffusion method for Listeria innocua, Staphylococus aureus, Escherchia coli, Salmonella typhi, Pseudomonas aeruginosa bacteria was 14/40, 16, 12, 14/30, 10, 10/10 mm respectively. The results showed that in combination of MPEO with gentamicin antibiotic, for all bacteria, synergistic was observed. In combination of MPEO, with chloramphenicol antibiotic in Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, synergistic state was observed. Minimum inhibitory concentration in MPEO for all bacteria was 6/25 mg/ml. In general, with regard to acquired results, one can use MPEO for pathogenic microorganisms growth control in foods.

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The chemical constituents of n-hexane extract of Mentha arvensis (wild mint) native to Meshginshahr and Namin region, and the antimicrobial effect of the extract against Pseudomonas aeruginosa (ATCC 27853) and Bacillus cereus (ATCC 11778) were studied in this research using broth and agar dilution methods (assessment of minimum inhibitory concentration, MIC, and minimum bactericidal concentration, MBC) and disk diffusion method. The results showed that cis-piperitone epoxide, piperitenone oxide and pulegone were the main components of the extracts. In addition, the MICs and MBCs of the n-hexane extracts of the wild mint in the various regions against P. aeruginosa were similar (20 mg/mL). Moreover, the MIC and MBC of the n-hexane extracts of the wild mint in Meshginshahr against B. cereus were 5 and 10 μg/mL, respectively, whereas the corresponding values against B. cereus were similar (10 mg/mL). Furthermore, the results of the disk diffusion test interpretation revealed that the inhibition zone diameters (IZDs) of the n-hexane extract in the samples obtained from Meshginshahr against both bacterial species were larger than those of the samples taken from Namin.