فهرست مطالب

International Journal of Molecular and Clinical Microbiology
Volume:8 Issue: 2, Summer and Autumn 2018

  • تاریخ انتشار: 1397/09/29
  • تعداد عناوین: 10
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  • Mohammad Faezi *, Samere Javanbakht, Farzaneh Aziz Mohseni, Fatemeh Alikhani Pages 982-992
    In this study, a total 108 bacterial strains with potential of antibacterial activity were isolated from 145 shoreline water samples of Caspian Sea. The isolated bacteria were: Gram negative and positive bacilli, Gram negative and positive cocci and Gram negative coccoid. Amongst 108 isolated bacterial strains, 12 strains (11%) showed significant antibacterial activity against 10 reference strains. Morphological, physiological, biochemical features and 16S rRNA analysis were used to identify the isolated strains with antibacterial activity. Amongst the isolated strains, six isolates possessed typical cellular, colonial morphologies, physiological, biochemical and nutritional features that resembled Bacillus spp. Four strains were identified as Bacillus cereus. The two other isolates belonged to Bacillus subtilis group. Two gram positive rod shape isolates were identified as Exiguobacterium acetylicum. The rest of isolates with antibacterial potency were gram negative bacteria. They were identified as Pseudomonas aeruginosa (3isolate) and Alcaligenes faecalis (one isolate). Crude extracts of Pseudomonas aeruginosa strains showed significant antimicrobial activity against all reference strains. Also, E.acetylicum and A. faecalis showed antibacterial activity against some reference strains such as Escherichia coli PTCC 1533, Shigella flexneri PTCC 1234 and Salmonella enterica subsp.enterica Paratyphi B PTCC 1231. The crude extracts of four isolates with wide antibacterial activity were used in TLC autobiography overlay assay. The TLC autobiographic overlay assay implied that the antimicrobial metabolites produced by the strains with wide antimicrobial spectrum were different.
    Keywords: Caspian Sea, antibacterial activity, isolation, marine bacteria, characterization
  • Shiva Mohammad, Gholamreza Amin, Mohammad Hassan Pouriayevali, Masoud Parsania * Pages 993-1000
    Herpes simplex virus type 1 (HSV-1) leads to various clinical manifestations in humans. Due to drug resistance, the use of herbs extracts for treatment has been considered as a significant solution. One of these compounds is Chelidonium majus L. herb extracts which is known as Mamiran in Iran. In this study, two aqueous and hexane extracts of Chelidonium majus L. were used to investigate the antiviral effects against HSV-1. The toxicity of hexane and aqueous extracts on HeLa cells was determined by MTT assay. Anti-viral effects of the extracts were evaluated directly, at different concentrations and times. The effect of the aforementioned extracts on reducing the virus replication was evaluated by quantitative Real-time PCR based on the glycoprotein D (gD) gene expression level of the herpes simplex virus. We observed that a 3500 μg/ml concentration of aqueous extract of C.majus and 600 μg/ml concentration of hexane extract were not toxic to HeLa cells. None of the extracts had a direct anti-viral effect on the virus. The aqueous extract at the above concentrations after 1, 2, 4, and 8 h of adsorption significantly reduced on virus replication. In contrast, the hexanic extract of this plant had no viral and inhibitory effect on HSV-1 replication. The aqueous extract of C.majus has an antiviral effect on HSV-1 compared to the hexane extract.
    Keywords: HSV-1, Chelidonium majus, Hexane Extract, Aqueous extract, Real-time PCR
  • Parisa Abedi, Hossein Dabiri *, Ehsan Nazemalhosseini, Sama Rezasoltani, HAMID Asadzadeh, Ramin Pouriran, Mohammad Javad Pages 1001-1005

    Colorectal cancer (CRC) has defined as the uncontrolled growth of cells in the colon or rectum. The human colon contains the greatest number of microbes Therefore, microbes may play an important role in the development of colorectal cancer. Recent studies have shown an association between the microbial infection and the risk of colorectal cancer. However, the results of these studies are controversial. The nobility of the present study was to assess the prevalence of Helicobacter pylori infection in the colorectal cancer in Iran. The biopsy were done and the samples were obtained from patients suspected with colorectal cancer, from 2015 to 2017.Secondary, DNA of Helicobacter pylori was extracted by Commercial kit. PCR was performed for Helicobacter pylori glmM gene eventually, the data was analysed. A total of 86 patients in which 68 of them confirmed with CRC and 17 patients considered as controls. Of 68 biopsy specimens and control group, all of them were negative for Helicobacter pylori. It was ultimately attained that in colorectal cancer, there was no presence of Helicobacter pylori.

    Keywords: Colorectal cancer, Helicobacter pylori, gastrointestinal diseases, PCR, Iran
  • Rezvan Eftekhari, Monir Doudi *, Gholamreza Amiri Pages 1006-1015
    Attention to the use of microorganisms, including fungi in nanoparticles production is due to their cleanliness, high adaptability to the environment and easily manufacturing. The aim of this study was biosynthesis of copper nanoparticles by fungi isolated from soil and industrial wastewaters and characterization of the synthesized nanoparticles. Sampling was carried out from the soil and waste water of several coppersmiths and plating plants in Isfahan. After analysis of chemical and biological parameters of samples, Czapek Dox medium containing CuSO4 was used for isolation of fungi. Minimum inhibitory concentration of copper ions on the selected fungi was assessed by agar diffusion method. The most resistant fungi were identified based on morphology and molecular detection. In the second step, copper nonoparticle production by selected fungi was investigated and the characteristics of the bionanoparticles were analyzed by X-ray diffraction (XRD), UV-visible spectroscopy and transmission electron microscopy (TEM). Among the Cu-resistant fungi, Fusarium solani CBS490.63 and paecilomyces variotii BAB-1547 possessed the highest resistance to copper with MIC of 4.5 mM and 4 mM, respectively. The results of UV-visible spectroscopy showed an absorption peak after applying the heat at 800 ⁰C in the wavelength of 400 nm. X-ray diffraction and TEM results showed that the copper nanoparticles were in the form of hexahedron with the diameter of 17-29 nm. The isolated fungi were efficient for biological synthesis of copper nanoparticles which have been detected with minimal environmental contamination and less toxicity than nanoparticles synthesis by physical and chemical methods.
    Keywords: biosynthesis, Copper nanoparticles, Fungi, XRD, UV-visible spectroscopy, TEM
  • Azar Sabokbar *, Marziyeh Motevalibashi, Somayeh Talebi Pages 1016-1022
    Background/
    objective
    In this study, the prevalence of potential Aspergillus flavus producing aflatoxin B1 in three different types of pepper in Tehran grocery has been investigated.
    Materials and Methods
    The experiments were performed on 90 samples of pepper, including 30 black pepper, 30 white pepper and 30 chilli peppers, and cultivated on Sabouraud dextrose agar. The isolation of the genus and species of fungi was performed by macroscopy and microscopy examination. In order to confirmation of A. flavus diagnosis, polymerase chain reaction (PCR) was performed using specific species primers. The ability to produce aflatoxin B1 was determined by specific primers to detect four genes from the aflatoxin B1 biosynthesis pathway.
    Results
    The results showed that the isolated fungi of red pepper samples consisted of 93.3% of Mucor species, 16.6% of Aspergillus niger and 3. 3% of A. flavus. Also isolated fungi from black pepper samples were 36.6% of Mucor species, 33.3% of A. flavus and 30% of A. niger. The results on white pepper represented 40% of Mucor species, 36.6% of A. niger and 33.3% of A. flavus. The results of PCR showed that all A. flavus possesses nor-1, ver-1, omt-1 and afR1 genes and potentially produced aflatoxin B1. Only one sample of white pepper and one sample of black pepper lacked the omt-1 and aflR gene, which are therefore unable to produce aflatoxin.
    Conclusion
    The presence of toxigenic fungi such as A. flavus in pepper can produce mycotoxin that affects the quality of pepper and causes human disorder.
    Keywords: Pepper, Aflatoxin B1, Aspergillus niger, Aspergillus flavus, PCR
  • Fatemeh Asghari, Masoumeh Anvari * Pages 1023-1031
    The purpose of this study was to evaluate the effect of drying on the survival and performance of probiotics in dried fruits. In this study, banana, apple, cucumber and apricot fruits and four probiotic strains including Lactobacillus acidophilus, Lactobacillus plantarum, Lactobacillus rhamnosus and Lactobacillus lactis were studied. The antimicrobial properties of Lactobacillus products before and after drying were investigated on four bacterial pathogens including Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa and Bacillus subtilis using batch fermentation system. Data analysis was analysis using Minitab software and the effect of different variables such as type of bacteria, temperature, drying time and type of fruit on the survival and probiotics function was evaluated using Taguchi experimental design.Lactobacillus spp. showed antimicrobial properties against pathogenic bacteria before and after drying. Also, data analysis showed that drying did not threaten the survival of probiotics, the highest growth rate for Lactobacillus rhamnosus was observed after 68 hours, indicating that, after drying, probiotics were retained for up to hours and were able to grow up. Finally, the analysis of the data showed that the bacterial species and different temperatures had a significant relationship with the survival of lactobacillus after drying. Therefore, probiotic dried fruits are proposed as a new idea in the food industry.
    Keywords: probiotic, Antimicrobial Activity, drying, discontinuation, Lactobacillus
  • Mahnaz Farahmand *, Elham Azizi, Mohammad Hassan Shahhosseini Pages 1032-1038
    L Glutaminase and L- methioninase, therapeutic enzyme obtained from microbial source have been considered in the treatment of cancer. A total 20 water samples were obtained from the Yale Gonbad hot spring in Qazvin province, Iran. Production capabilities L Glutaminase and L- methioninase were tested on m9 and mcd plates, respectively. Enzyme-producing isolates were identified by conventional test and then confirmed using molecular methods. The PCR amplicons were directed for sequencing and Phylogenetic tree were drawn using Mega version 6 software. Twelve colonies were obtained from all tested samples. Three extratermophilic isolates showed L-glutaminase activity in M9 medium but only 1 isolates have L-methioninase activity in MCD medium. The phylogenetic tree drawn from the 16 S rRNA gene sequence showed were 100% similar to B. licheniformis and strains of S. epidermidis and L. sphaericus. In this study, Bacillus licheniformis was identified as a dominant and a native strain for the production of L-glutaminase and L-methioninase.
    Keywords: extremophilic bacteria, L-glutaminase, L- Methioninas, anticancer, Iran
  • Nazanin Pasandideh, Masoumeh Anvari * Pages 1039-1047
    Antibacterial activity has recently been demonstrated in olive products. This antibacterial effect was correlated with the presence of different substances such as oleuropein. In present work antibacterial activity of different olive products was examined and their oleuropein content were determined. Also, the effect of different factors on antimicrobial activity were assayed by Taguchi methodology. Three varieties of fruit, leaves, and unrefined olive oil were purchased from Roodbar in Guilan province and ethanolic extract was examined. Antimicrobial activity of leaves and olive fruits were performed by disk and well diffusion, and pore plating method. Also, according to Taguchi methodology, effect of different factors such as incubation time, bacterial suspension concentration, type of bacteria, and type of extracts on antibacterial activity were evaluated. HPLC was performed to measure the oleuropein content at the Science and Technology Park of Guilan. Data analyzes were performed by using Minitab software. Leaves, fruits, and oil olive extract had significant impact on E. coli, S. aureus, and P. aeruginosa. Data analysis showed that exposure time and type of extracts had a significant antimicrobial effect on pathogen bacteria. Also, fruit extract had greater antimicrobial activity than olive oil. Eventually, S. aureus was (susceptible) than E. coli and P. aeruginosa to olive extracts. In current study, HPLC confirmed oleuropein as main antimicrobial ingredient of olive at 2.63ppm. In this study, antimicrobial activity of olives products against E. coli, S. aureus, and P. aeruginosa demonstrated that different extracts of olive have potential for preparation herbal medicines.
    Keywords: disk diffusion, Olive, ethanol, HPLC, E. coli
  • Alireza Mokhtari *, Saeed Hosseini, Shahnaz Pourhossein, Nahid Soleimanifard Pages 1048-1061
    Fusarium is one of the most important pathogens of cereals; the fungal infection has increased in recent years due to ecological changes and soil nitrogen content increase. In the current study the effect of cumin oil essence on fusarium verticillioides by molecular method was investigated. The study included 14 isolates, 11 isolates of fusarium verticillioides and 3 Fusarium non verticillioides samples (negative control) were tested. For testing MIC and MFC, the RPMI1640 culture in microplate was used. After a week, the cultured RNA samples using the RNA extraction kit of Fermentas company (Purification Mini Kit GeneJET Plant RNA) was extracted from fungal biomass and the RT-PCR test along with the FUM1 gene was performed. The RT-PCR analysis displayed that FUM1 gene was expressed in fungal samples that were not under the effects of oil essence, but the gene was not expressed in samples after the cumin impact and there was not any band in agarose gel. the B1 fumonisin toxin which was produced by the fungus fusarium verticillioides contains several genes. The gene FUM1was involved toxin gene synthesis pathway of this toxin as the most essential gene.
    Keywords: Fusarium verticillioides, Fumonisin, cumin, FUM1, ITS
  • Elmira Shakiba, Hadi Koohsari *, Mehr Ali Mahmoodjanloo Pages 1062-1073
    The biological activities of bee products vary according to plant origin, geographical region and climatic characteristics. This study aimed to investigate the antibacterial activity of honey and propolis samples from different geographical regions with different climate. Samples included three honey samples and three propolis samples were collected from three areas of the Plain, Mountain and Forest of Golestan province in north of Iran. Antibacterial activity was evaluated by agar well diffusion method and MIC and MBC were determined by broth macrodilution tube method.  The results of the present study revealed that antibacterial activity of the honey collected from forest areas is higher than other honey samples so that the MIC of this honey sample was in the range of 12.5 to 25%. The propolis collected from plain areas showed the highest antibacterial activity with MBC in the range of 12.5 to 50 mg/ml. The gram-positive bacteria in comparison of gram-negative bacteria and standard strains in comparison of native isolates were showed more sensitive to these bee products. The standard strain of S. aureus and the native isolate of P. aeroginosa were the most sensitive and the most resistant of the bacteria respectively. Difference and variation of antibacterial activity of bee products can be due to the difference in the various plants that bees have fed. Due to the complications associated with antimicrobial chemical compounds, identifying of effective compounds of these products can hope for us to introduce a natural drug combination or a natural food additive.
    Keywords: Honey, Propolis, Antibacterial activity, Geographical regions, Golestan Province