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Molecular and Clinical Microbiology - Volume:7 Issue: 2, Summer and Autumn 2017

International Journal of Molecular and Clinical Microbiology
Volume:7 Issue: 2, Summer and Autumn 2017

  • تاریخ انتشار: 1396/10/10
  • تعداد عناوین: 10
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  • Meira Erawati *_Megah Andriany_Niken S. D Kusumaningrum Pages 816-823
    Tuberculosis is an infectious disease which occurs widely in the world and becomes one of the top 10 causes of death worldwide. Mutations of the RpoB gene cause the resistance of Mycobacterium tuberculosis to rifampicin that contributes to the occurrence of MDR-TB. This study aimed to determine the pattern of rpoB gene polymorphisms in the MDR M. tuberculosis in Semarang, Indonesia. Most mutations occurred at codon Ser531Leu (13 isolates), codon Gln490Lys (7 isolates) and codon 526 (5 isolates). Variations of mutation mostly occurred at codon 526 with 4 variations of nucleotide changes, including His490Leu, His490Cys, His490Ser and His490Tyr. The types of mutation were missense mutations (30 mutations) and silent mutation (1 mutation). The mutations in the rpoB gene of MDR M. tuberculosis isolates in Semarang showed genetic variations that caused high levels of resistance to rifampicin.
    Keywords: MDRTB, M Tuberculosis, rpoB gene, mutation, rifampicin
  • Alireza Massiha *, Mohammad Reza Majid Khoshkholgh Pahlaviani Pages 824-833
    The main purpose of the study is to determine resistance pattern of bacterial isolates to selected antibiotics among 88 dyspeptic patients in Iran. Frequency of infection among these patients have been evaluated among dyspeptic patients old (45 boys and 43 girls, aged 5-18 years) from 2016 to 2017.Eighty-eight patients with gastroduodenal disorders were included in the study. Urease test modified Giemsa stain, culture isolation and histopathology of H.pylori isolates were performed as per standard guidelines. H.pylori ATCC 43504 was used as reference strain. Susceptibility of HP isolates to amoxicillin, tetracycline, metronidazole, clarithromycin and levofloxacin was determined using EUCAST break points by E-test method. Antral gastritis caused by H pylori infection (15.91%) with or without extension into the duodenum was prominent endoscopic finding. The study revealed modified Giemsa stain positivity of 13.6%, urease test positivity 23.9%, and culture positivity rate of 18.2%. The three tests Culture, Giemsa, and Urease test found to be significant statistically (P
    Keywords: Gastrointestinal disorders, Helicobacter pylori, Antibiotic resistant, E-test, Iran
  • Adeleh Attar, Hesam Mirshahabi, Fakhri Haghi, Habib Zeighami * Pages 834-840
    Sub Minimal Inhibitory concentrations (sub-MIC) of antibiotics, although not able to kill bacteria, can be effect on their physico- chemical characteristics and functions. This study aimed to investigate the effect of sub-MIC of imipenem and piperacillin on the transcriptional expression of virulence related genes algD and lasB in Pseudomonas auroginosa. Five clinical isolates of P. aeruginosa were screened for the presence of algD and lasB genes and minimum inhibitory concentration (MIC) of imipenem and piperacillin was determined using tube dilution method. The expression level of algD and lasB at sub-MIC concentrations of antibiotics was measured by real-time PCR. Our results showed that the expression of the lasB strongly decreased at all sub-MIC of piperacillin, especially at concentrations 0.125 and 2 µg/ml (P
    Keywords: Subinhibitory concentrations, Pseudomonas aeruginosa, algD, lasB, Imipenem, Piperacillin
  • N. Nikoei, Nima Bahador * Pages 841-848
    Cyanobacteria are major group of microorganism with capability to produce different types of toxin. Indeed, anthropogenic eutrophication of surface water is the main reason for acceleration of their growth and ecological problems. Therefore, the present study tried to isolate toxic cyanobacteria from Kor River, Fars province. For this purpose, 18 water samples were collected from three sampling stations of Kor River, namely: Rah-Ahan Bridge, Esfandaran and Khan Bridge stations. The samples were serially diluted and cultivated on BG11 media under illumination of 1500 to 2000 lux with 12/12 h light/dark regime at 28 ± 2 °C. Then the colonies were purified and molecularly identified using three sets of primers. The toxins were extracted according to Anjos protocols and confirmed by HPLC. Finally, effect of titanium dioxide under ultraviolet lights with a wavelength of 450-330 nm for half an hour evaluated. The results obtained from this study indicated that 4 different isolates were detected from sampling sites. The isolates had capability to produce toxins ( Microcystin, Cylindrospermopsin) and their presence were confirmed by HPLC. In addition, the toxins were affected by titanium dioxide. Although the titanium dioxide has detoxifying ability, evaluation of different concentration of titanium dioxide on different types of toxins is suggesting.
    Keywords: Cyanobacteria, Molecular identification, Toxins, Tianium dioxide, Kor River
  • Soheila Bagherzadeh, Khosro Issazadeh * Pages 849-854
    Urinary tract infection is one of the most common bacterial infections of human. The most common agent of urinary tract infection is Escherichia coli . This study aims to determine the prevalence of uropathogenic E. coli urinary infection in human with different antimicrobial resistance, and quantitive and qualitative study of siderophore production and their association with the ability to cause infection with the isolated E. coli. All of these studies have been done in Aria hospital at Rasht city (Iran). One hundred thirty samples from patients with urinary tract infection were collected. Serotyping was performed according to agglutination on the slide. Qualitative measurements of siderophore were performed by colorimetric or liquid assay and determination of the type of produced siderophore was also done by Csaky’s Assay and Arnow’s Assay. Different antibiotics sensitivity tests performed with Kirby Bauer and disk diffusion. From the 130 samples, 33 cases of urinary tract infections were related to E.coli. Among them they showed the most susceptibility to nitrofurantoin antibiotic. Most of the serotypes were O1, O29, O126, and O159. It was revealed that 87.5 % of the samples, were positive for siderophore and according to the OD, the samples of enterobactin siderophore were more than the aerobactin siderophore in all isolates. In general this study showes that most of the strains produce siderophore and shows that the nitrofurantoin is the best antibiotic to treat urinary tract infections caused by E. coli.
    Keywords: E. coli, urinary infection, siderophore, antibiotic, serotype
  • Jamshid Raheb*, Seyed Abolghassem Mohammadi Bondarkhilli, Mehdi Mohmmadi, Kambiz Akbari, Hossein Shahbani, Arefeh Alipour Pages 855-868
    Today, efforts go towards the replacement of chemical surfactants by natural biological biosurfactants (biosurfactant), as these materials are not carcinogenic and highly compatibile with the environment. One of the main classes of biosurfactants is rhamnose containing glycolipid biosurfactant (rhamnolipids). This type of biosurfactants can be applied in many industries such as oil industry, pharmaceutical industry, food industry and esc. In the present study, with elimination of regulatory elements of monorhamnolipid operon, the suitable construct was made and transformed to E. coli BL12 and E. coli DH5α competent cells. Then the production of monorhamnolipid in recombinant E. coli BL12 harboring pET 12a vector and mono and di-rhamnolipid biosurfactant in recombinant E. coli DH5α harboring pTrc 99A evaluated by CTAB plate and thin layer chromatography (TLC). The relative production of mono and dirhamnolipid biosurfactant was determined by oil spreading method. Finally, the efficiency of the extracted biosurfactant was verified by E12 method in different salinity and pH conditions.
    Keywords: Biosurfactant, Rhamnolipid, E. coli BL12, E. coli DH5α Transformation
  • Sevil Nematollahi *, Mitra Sayidi Pages 869-874
    Increasing public concerns about fungicide residues have prompted interests in biological control especially use of herb extracts derived from several medicinal plants as an alternative strategy for disease management. Recently tomato leaf spot disease caused by Alternaria alternata has become epidemic in almost areas of Iran. This study was conducted for the identification of the effect of antifungal activity of two medicinal plants extracts; Mentha pulegium L. and Urtica dioica L. against A. alternata. Both plant extracts exhibited antifungal potential against the pathogenic fungus. The Nettle extract showed a more degree of inhibition with 59.78% and 77.81% inhibition rate at concentration of 1000 and 1500 ppm, respectively. The inhibition of the mycelial growth was strongly reduced in the concentration of 1500 ppm of both plant extracts. The results of this study confirm that extracts of the selected medicinal plants can be used as an alternative fungicide in control of this pathogenic fungus.
    Keywords: antifungal activity, extracts, medicinal plants, tomato, Alternaria
  • Narges Vaseghi, Mansour Bayat *, Arash Chaichi Nosrati, Mahmood Ghorannevis, Jamal Hashemi Pages 875-889
    Mycotoxins such as Citrinin are small toxic molecules produced by a great variety of microorganism, which encompass several classes of secondary metabolites with no common chemical structure or mode of action. Citrinin produces by different species of Penicillium. Today, the cold atmospheric pressure plasma (CAPP) method has a potential for mycotoxin detoxification. In this study, a new and promising approach involving the use of cold atmospheric pressure plasma is considered, which may overcome multiple weaknesses associated with the classical methods.
    In this study, samples included wheat, corn; rice and Barley were obtained from northern parts of Iran (Lahijan). Initially, the output of the power supply was set to 50 kV, 100 watts, and the electron frequency of 30 kHz (optimal conditions to effective plasma). Then, the effect of cold atmospheric jet plasma (argon) on gas was investigated in 30, 60 and 360 seconds (gas flow rate of 6 liters per minute).
    The results showed us that the cold atmospheric pressure plasma method effectively production pure mycotoxins. The rate of various mycotoxins destruction varies according to their structure. It was also shown in the study that the combination of mycotoxins in foods would reduce the plasma's effect, but not prevent them from degrading. Finally, in this study, descendants in all samples were performed successfully.
    The atmospheric pressure plasma method has a natural biodegradation effect and has the least negative effect on food products in comparison with conventional methods of disinfection of food products in addition to the detoxification characteristics.
    Keywords: Citrinin, Penicillium, Mycotoxin, Cold Atmospheric Pressure Plasma, detoxification
  • Mostafa Noorizadeh *, Orkideh Hajipour Pages 890-895
    Brilliant blue is largely found in ice cream, canned processed peas, packet soups, blue raspberry flavored products, dairy products, sweets and drinks. It is also used in soaps, shampoos, mouthwash and other hygiene and cosmetics applications (Archived from Florida). This study was aimed to investigate the antimicrobial effects of Brilliant blue on Bacillus subtilis as a gram positive bacterial strain and Pseudomonas aeruginosa as a gram negative bacterial strain with MIC, MBC, and disk diffusion assay. MIC values of Brilliant blue against Bacillus subtilis was 5µg/ml, and MBC values was 60 µg/ml and MIC values of Brilliant blue against Pseudomonas aeruginosa are 10 µg/ml, and MBC values was 80 µg/ mL. In this study Brilliant blue had only a bacteriostatic effect on two bacterial strains. The result of disk diffusion assay showed that Brilliant blue (0.625, 1.25, and 1.875 µg) has not antimicrobial activity against Bacillus subtilis and Pseudomonas aeruginosa. It can be concluded that Brilliant blue might not pose a potential risk for our bacterial flora. However, it must be evaluated with different new studies.
    Keywords: Brilliant Blue, Food Dye, Antimicrobial effect, Bacillus subtilis, Pseudomonas aeruginosa
  • Zahra Mahdavi Niaki, Majid Alipour *, Yousef Yahyapour, Fatemeh Mahdavi Niaki Pages 896-902
    Staphylococcus aureus is colonized in the human nasal cavity and would contaminate hospital and therapeutic environments. This bacterium has a genetic diversity in terms of resistance to antimicrobial agents. Therefore, the purpose of this study was identificatied of Methicillin and Vancomycin resistant genes in Staphylococcus aureus strains which has been isolated from the nasal cavity. 189 patients referred to Amol city health center were sampled. Staphylococcus aureus identification was performed by standard methods. Resistance to antibiotics of Vancomycin, Methicillin, Cefpime, Ceftriaxone, Cefixime, nalidixic acid, Cefazolin, Stiffenoxime, Cefotaxime, Ceftazidime, Imipenem and Ciprofloxacin were identified by disk diffusion method and recommendations of the Laboratory and Clinical Standardization Organization (CLSI). Polymerase chain reaction was performed to detect mecA, vanA and femB genes. 32.2% of the patients were carriers of Staphylococcus aureus in their nose. In this research, 68.85% of the isolates were resistant to Methicillin. 100% resistance to Cefixime and Nalidixic acid antibiotics was observed. Subsequently, the highest amounts of resistance belonged to Cefazolin (96.72%) and Cefepime (86.88%). Resistance to Vancomycin was 70.49%. The lowest amounts of resistance were observed in the two antibiotics Ciprofloxacin and Imipenem, with incidences of 6.55% and 9.83% in isolates, respectively. Genetically, no resistance was observed for Vancomycin and none of the tested isolates were carried vanA gene. Of 61 separated Staphylococcus aureus, 77.04% of them carried mecA gene and 90.16% of them had femB gene. This study showed that the main resistance to Penicillin, Oxacillin and Methicillin in Amol city is due to mecA and femB genes.
    Keywords: Staphylococcus aureus, Methicillin, Vancomycin, PCR, resistant, nasal cavity