Microbiol. Res., Volume 8, Issue 2 (November 2017) – 13 articles

Campylobacter species are the most important pathogens that cause bacterial gastroenteritis being spread through food with animal origin. Given such fact, the current study aimed at investigate the prevalence of Campylobacter based on phenotypic and genotypic analysis of poultry meat and edible offal in Western Azerbaijan. To conduct the study, a total of 552 chicken samples including meat (samples), liver (138 samples), gizzard (138 samples) and hearts (138 samples) were randomly collected from poultry slaughterhouses at West Azerbaijan province from April 2014 to September 2014. Based on the culture tests, 208 samples (37/7%) were contaminated with Campylobacter species. The highest range of Campylobacter species out breaks was observed in poultry liver (49/2%), followed by gizzard (42/8%), heart (33/3%) and meat (25/4%). Among the isolated Campylobacter, C. jejuni was the most prevalent (78/4%) and the rest were C. coli species (21/6%). All 208 species of Campylobacter isolated as C. jejuni and C. coli from species culturing were also approved by m.PCR. The results of the study pinpointed to the chicken edible offal importance as a potential source of Campylobacterial contamination. Full article

With the increase of patients suffering from immune deficiency infections also increased pulmonary fungi even in people with defective immune system can cause fatal and lethal candidiasis. The timely diagnosis of pulmonary candidiasis is one of the problems that has been detected. Polymerase chain reaction (PCR) test and Loop mediated isothermal amplification (LAMP) method optimized on the basis of α INT1 gene and then sensitivity and specificity were evaluated. LAMP is a novel nucleic acid amplification technique with high specificity and sensitivity which has been done under isothermal condition. Samples were the bronchoalveolar lavage suspected of tuberculosis (TB) reviews for TB disease negative have been reported. DNA extraction carried out by standard phenol/chloroform method on samples and PCR test and LAMP was done. PCR and LAMP testing was performed on samples and products of 441 bp were amplified and observed with agarose gel electrophoresis. At the end of the LAMP reaction, SYBR Green was used for identifying negative and positive results. Among the 60 quantities sera, only 7 cases were PCR positive but 8 cases were LAMP positive. In comparison, between LAMP and PCR, the LAMP technique in spite of its simplicity, high sensitivity and specificity, could be an appropriate replacement for PCR. Full article

Enteric fever, Dengue and malaria still remain diseases of public health importance in the tropics. Individuals residing in endemic areas are at risk of contracting these infections either concurrently or an acute infection superimposed on a chronic one. This study was undertaken to document patients showing co seropositivity for Enteric fever, Malaria and Dengue and to record the baseline Salmonella antibody titer in voluntary blood donors who represent general population of the area. The present study was conducted in the Department of Microbiology, J.J.M. Medical College, Davangere. Among the 824 febrile patients enrolled with positive serological test for either Typhoid, Dengue or Malaria, 189 patients were found to have co seropositivity to any two of the above diseases on subjecting their serum to Widal test, Dengue ELISA and malaria antigen detection by immunochromatography. A total of 189 patients showed co seropositivity for any of the above mentioned diseases accounting for 22.90%. Typhoid-Dengue was found in 9.83% Typhoid-Malaria in 6.67% and all the three in 0.48%. Dengue- Malaria co-seropositivity was recorded in 5.94%. The basal titer in healthy population was found to be <1:20. The co seropositivity rate in our study is 22.9% which poses a challenge in the diagnosis and treatment of such patients. As the gold standards culture and microscopy are time consuming and molecular diagnostic tools not a practical reality in many rural and developing primary health centers, simple, rapid and sensitive serological methods are being used as an alternative diagnostic tool in diagnosing atypical co infections which in some instance leads to overwhelming diagnosis of co infections and improper treatment. Full article

The indoleacetic acid produced by symbiotic bacteria is an important phytohormone signaling microbe-plant interaction, being therefore essential for rhizoremediation. In this study, the effect of different concentrations of copper ions on the bacterial growth and indoleacetic acid production was investigated in two strains of Mesorhizobium loti in in vitro conditions, aiming to determine critical concentrations of this heavy metal for rhizoremediation of contaminated soils using this bacterium. The experiment consisted on a control culture without copper and three treatments supplemented with 10 mg.L^-1, 20 mg.L^-1 or 50 mg.L^-1 of CuSO₄. For both strains, the growth stopped after 48h and no significant difference was observed across treatments. The production of indoleacetic acid by the control treatment without copper was significantly higher in comparison to the copper- containing treatments. Mesorhizobium loti SEMIA806 and SEMIA816 are resistant to up to 50 mg.L^-1 of CuSO₄ in the culture medium, presenting effective growth. The synthesis of indoleacetic acid was strongly reduced but not excluded by ions copper in the medium. So, it is expected that environmental copper found in the soil up to the concentration of 50 mg.L^-1 will not preclude the symbiotic interaction between M. loti and leguminous host plant in rhizoremediation enterprises. Full article

Lack of proper hygiene and using from low quality raw materials cause high presence of food-borne pathogens in ready to eat foods. Shiga toxin producing Escherichia coli is one of the most common cause of food-borne diseases in the world. The present research was done to study the prevalence and distribution of virulence factors in the STEC strains isolated from various types of ready to eat food samples. Seven-hundred and twenty food samples were collected and cultured. Isolated E. coli bacteria were approved another time using the 16S rRNA-based PCR amplification. Approved strains were subjected to multiplex PCR for identification of putative virulence factors. Twenty-six out of 720 food samples (5.20%) were positive for E. coli. Salad (15%), candy (12.50%) and barbecue (10%) were the most commonly contaminated. Prevalence of STEC strains was 2.63%. Prevalence of EHEC and AEEC subtypes were 36.84% and 52.63%, respectively. EHEC strains harbored all three stx1, eae and ehly genes. High presence of EHEC strains besides the considerable distribution of multiple virulence factors showed an important public health issue regarding the consumption of ready to eat foods. Full article

Various rhizobacteria strains are isolated and tested worldwide for their plant growth promoting activities. A strain is said to be a plant growth promoter if it has the ability to influence plant growth directly or indirectly. Though the main focus has always been to realize the plant growth promoting traits of rhizobacteria and use them as biofertilizers, but the disadvantages or deleterious effects of such plant growth promoting rhizobacteria (PGPR) if any have also been ignored to a greater extent. The present study deals with the characterization of both promoting as well as deleterious activities of an isolated strain of Pseudomonas aeruginosa on plants. The bacterium was isolated from the soil of the college campus of Babasaheb Bhimrao Ambedkar University, Lucknow, Uttar Pradesh and was characterized as P. aeruginosa by various positive biochemical tests such as oxidase, catalase, citrate tests and confirmed by MALDI-TOF-MS. Its growth as well as IAA producing ability at different salt (NaCl) concentrations was tested. Tests examining HCN, Ammonia and siderophore production, flocculation ability, phosphate and zinc solubilization by the strain were carried out. Its anti-microbial property was tested against three phytopathogenic fungi: Fusarium solani, Aspergillus niger and Curvularia lunata and two bacterial strains - Klebsiella pneumoniae and E. coli. Its effect over seed germination of Triticum aestivum and Zea mays was inspected in plates as well as in pots. The strain showed a great potential as a plant growth promoter growing up to 10% NaCl concentration and producing considerable amount of IAA upto 8% NaCl concentration. It showed antagonistic nature against the three phytopathogenic fungi, solubilized phosphate and produced siderophore and NH3. Though supernatant of the bacterial culture did not show any deleterious effect over seed (of the test plants T. aestivum and Z. mays) germination but the seeds inoculated with the strain itself, failed to germinate. The seed turned dormant and grew a pale brown color showing bacterial growth over it. Thus it maybe concluded that the isolated strain of P. aeruginosa has abilities to both promote and at the same time inhibit plant growth (by inhibiting seed germination). Full article

Packaging using chitosan-based edible films incorporated with natural essential oils is a safe and economic way to increase the shelf-life and acceptability of food products and especially chicken meat. Trachyspermum ammi is a natural medicinal plant with high antimicrobial effects cultivated in Iran. The present research was done to study the antimicrobial effects of chitosan-based edible film containing T. ammi essential oil on shelf-life of chicken meat. T. ammi fruits were collected and dried. Essential oil was extracted from plants using the Clevenger’s apparatus. High molecular weight chitosan with 1% and 2% concentrations of T. ammi essential oil were used for coating of chicken fillets. Treatments were stored at 4 °C for 12 days. Count of the total aerobic, total psychrophilic and coliform bacteria had ranges of 3.8 ± 0.25 to 8.32 ± 0.26, 4 ± 0.23 to 8.65 ± 0.28 and 1.8 ± 0.09 to 5.62 ± 0.16 CFU/g during the storage period. Antimicrobial effects were significantly increased with the incorporation of T. ammi essential oil (p < 0.05). Antimicrobial effects were also depended on the concentration of T. ammi essential oil (p < 0.05). Chitosan film incorporated with 2% T. ammi essential oil had the highest inhibitory effects on total aerobic, total psychrophilic and coliform bacteria (p < 0.05). Our results pointed out that the incorporation of T. ammi essential oil at 2% concentration has potential for using the developed chitosan edible film as an active packaging of chicken meat. Full article

Antibiotic resistance in Escherichia coli is a global health concern. We studied all possible routes of cross contamination of broiler meat with resistant E. coli from broiler feces at poultry shops. Various sample categories namely poultry feces, meat (n = 225 for each), slaughterer hands, consumer hands, slaughterer knife, canister, tap water, carcass, feed and drinking water (n = 50 for each) were collected from local poultry processing market. Samples were screened for prevalence of E. coli, resistance of isolates against ten antibiotics and presence of tetracycline- resistance genes in the isolates. Fecal samples had greatest colony count (4.1 × 10⁴ CFU/g) as compared to meat (1.9 × 10⁴ CFU/g) samples. Samples of consumer hands (6%) and tap water (12%) had less prevalence percentages of E. coli as compared to slaughterer hands (92%) and drinking water of broiler (86%). Isolates of eight sample categories had high resistant rate (≥90%) against oxytetracycline. On average, about 94% of the isolates from various sample categories possessed multidrug-resistance (MDR). Tetracycline-resistance genes (tetA and tetB) were identified in all sample categories except isolates of consumer hands and tap water. The distribution of tetracycline-resistance genes was significantly greater in fecal isolates (42%) than meat isolates (25%). The study depicted the spread of resistant E. coli in broiler meat through all studied routes of contamination of slaughtering periphery. This problem can be mitigated by strict monitoring of antibiotics use at poultry farms, prevention of cross contamination by adopting hygienic slaughter and vigorously screening the market meat for resistant E. coli. Full article

High occurrence of antibiotic resistance in pathogenic bacteria is caused by the use of natural medicinal plants to eliminate risk of infectious diseases. Glycine max is on the most popular and nutritious foods with high antimicrobial effects. The present research was done to study the antibacterial effects of the methanolic extract of G. max against Gram-negative and positive bacteria. G. max seeds of M7 and M9 varieties were purchased and their methanolic extracts were collected. Diameter of the zone of growth inhibition of extracts were measured for pathogenic bacteria using the CLSI guidelines. Antimicrobial effects of G. max extracts were also compared with several antibiotics. Diameter of the inhibition zone of tested bacteria against different treatments of G. max had a ranges of 5.93 ± 0.18 to 22.61 ± 1.80 mm. M7 variety had a higher antimicrobial effects on tested bacteria (p < 0.05). The highest diameter of the zone of growth inhibition was seen for L. monocytogenes (22.61 ± 1.80 mm) and S. aureus (19.33 ± 1.56 mm). Antimicrobial effects of the methanolic extract of the G. max was also dose-dependent (p < 0.05). Diameter of the inhibition zone of tested bacteria against different antibiotic agents had a ranges of 5.94 ± 0.38 to 24.95 ± 2.11 mm. Ciprofloxacin, penicillin G tetracycline, gentamicin and azithromycin antibiotic agents exhibited the highest diameter of zone of the growth inhibition for K. pneumoniae (15.71 ± 1.46 mm), L. monocytogenes (23.94 ± 2.03 mm), L. monocytogenes (20.55 ± 1.95 mm), S. aureus (14.27 ± 1.36 mm) and L. monocytogenes (24.95 ± 2.11 mm), respectively. Formulation of antibiotic agent using the 100 mg/mL concentration of the M7 variety of G. max has been recommended for treatment of the cases of infectious diseases. Full article

A direct transfer of plasmid pBP517 from C600 to J53 Escherichia coli K12 strains by electroporation, either by the standard method, or in the presence of 20 μg/mL of DNAse was carried out. In a standard experiment, donor and recipient bacteria were mixed and subjected to the electroporation procedure, about 2700 (range 1600–3700) recombinants were found, while no colonies were detected from non treated bacteria. When the same tests were performed at the presence of DNAse the number of recombinants fell to about 200 (range 183–218). This difference between the number of colonies found in the presence or in absence of DNAse was observed every time the tests were repeated. According to these observations, plasmid DNA has been transferred from donor to recipient cells via electroporation also when DNAse was added. Since the free genetic material is destroyed by the enzyme and recombination takes place it has been hypothesized that there must be a direct contact between the partner cells. Full article

Pseudomonas aeruginosa is one of the most important opportunistic pathogens responsible for various types of hospital infections. High prevalence of antibiotic resistance in P. aeruginosa strains of human clinical samples cause more severe diseases for a longer period of time. The current research was done in order to study the distribution of blaIMP-1 gene among the imipenem-resistant P. aeruginosa strains isolated from burn and urinary tract infections of hospitalized patients. Two-hundred and forty-three P. aeruginosa isolates recovered from the cases of burn and urinary tract infections of inpatients and outpatients were analysis for antibiotic resistance pattern using the disk diffusion method. Then, imipenem-resistant isolates were further analyzed for distribution of blaIMP-1 gene using the PCR. Of 243 P. aeruginosa isolates, 146 strains (60.08%) were taken from outpatients and 97 strains (39.91%) were taken from inpatients. P. aeruginosa isolates harbored the highest levels of resistance against streptomycin (100%), nalidixic acid (100%), aztreonam (100%), cotrimoxazole (95.47%), ciprofloxacin (88.47%), cefotaxime (84.36%) and gentamycin (83.95%). Inpatients had a relatively higher levels of antibiotic resistance. One-hundred and twenty-one out of 126 (96.03%) imipenem-resistant P. aeruginosa isolates harbored the blaIMP-1 gene. Inpatients also had a relatively higher prevalence of blaIMP-1 gene. High prevalence of blaIMP-1 gene and also imipenemresistant P. aeruginosa are important public health issue. Clinical laboratories should consider the detection of the blaIMP-1 gene among the P. aeruginosa isolates of clinical samples. Full article

In despite of the high clinical impact of Helicobacter pylori, its exact sources and routes of transmission are unknown. Dogs may play an imperative role in the transmission of H. pylori to humans. The current investigation was done to study the status of vacA and cagA genotypes in the H. pylori strains of dogs. One-hundred and fifty fecal samples were collected from healthy and complicated household dogs. Genomic DNA was extracted from fecal samples and presence of 16S rRNA gene was studied using the PCR amplification. Distribution of vacA and cagA genotypes were studied by the multiplex PCR. Thirteen out of 150 fecal samples (8.66%) were positive for H. pylori 16S rRNA gene. Prevalence of H. pylori in healthy and complicated dogs were 5.55% and 8.57%, respectively. Male had the higher prevalence of H. pylori (P=0.038). The most commonly detected genotypes among the H. pylori strains were vacAs1A (61.53%), cagA (38.46%), vacAm1a (38.46%), vacAs2 (30.76%) and vacAm2 (30.76%). The most commonly detected combined genotypes were s1aCagA (30.76%), s1am1a (23.07%), s2m1a (23.07%) and s2CagA (23.07%). Iranian household dogs harbor H. pylori in their fecal samples similar in genotypes of the vacA and cagA alleles which suggest that complicated and even healthy dogs may be the latent host of the H. pylori and its genotypes. However, supplementary studies are required to found the exact role of dogs as a definitive host of the H. pylori. Full article

Notwithstanding the substantial clinical impact of Helicobacter pylori, its convinced routes of transmission and sources have not been reported. Based on the quarrelsome hypothesis, foods and especially dairy products play an authoritative role in the transmission of H. pylori to humans. The current investigation was done to study the prevalence rate and distribution of vacA genotypes in the H. pylori strains isolated from the raw milk and traditional dairy products. Three-hundred milk and dairy samples were collected and directly transported to laboratory. Samples were cultured and H. pylori isolates were approved using the 16s rRNAbased PCR amplification. Positive strains were tested for distribution of vacA genotypes using the multiplex-PCR. Sixty out of 300 samples (20%) harbored H. pylori. Prevalence of H. pylori in milk and traditional dairy products were 38.75% and 13.18%, respectively. Ovine milk (45%) and traditional cheese (40%) had the highest prevalence of H. pylori. VacAs1a (91.66%), vacAm1a (61.61%) vacAs2 (36.66%) and vacAm2 (31.66%) were the most commonly detected genotypes. Ovine milk and traditional cheese had the most diverse genotypes. S1am1a (41.66%), s2m1a (25%), s1am2 (16.66%) and s2m2 (13.33%) were the most commonly detected combined genotypes. Raw milk and traditional dairy products are latent sources of H. pylori. Similarity in the genotyping pattern of H. pylori strains of various samples represents their similar sources of infection. Further studies are required to found the exact sources of H. pylori strains in raw milk and traditional dairy products. Full article