Open Access Minireview Article

Commensals and Foodborne Pathogens can Arbitrate Epithelial-carcinogenesis

Yvon Woappi, Om V. Singh

Microbiology Research Journal International, Page 1-11
DOI: 10.9734/BMRJ/2016/26690

Major shifts in intestinal commensal bacteria often result in changes in CD4+ T lymphocyte populations, leading to an influx of Th17 cells, chronic inflammation, and eventually cancer. Consequently, the inappropriate propagation of certain commensal species in the gut has been associated with mucosal inflammatory diseases and cancer development. Recent experiments investigating the relationships between food-borne pathogens, enteric bacteria, and cancer have exposed the ability of certain bacterial species to significantly reduce tumor size and tumor progression in mice. In similar studies, pro-inflammatory Th17 and Th1 cells were at times found present along with anti-inflammatory Treg populations in the intestinal mucosa. This antitumor response was mediated by a balanced production of pro- and anti-inflammatory cytokines, resulting in a controlled threshold of mucosal immunity largely moderated by CD4+ T lymphocyte populations, through a dendritic cell-dependent pathway. These findings provide new evidence that certain species of bacteria can help manage subcutaneous tumor development by calibrating mucosal and, in some instances, systemic thresholds of innate and adaptive immunity.

Open Access Original Research Article

Incidence of Heat-Labile Toxin (LT) Producing Enterotoxigenic Escherichia coli Mediated Diarrheal Disease in Egyptian Children under 5 Years Presenting to Tanta University Hospital

M. A. Abd El-Wahab, M. A. Shams eldin, M. A. Naiem

Microbiology Research Journal International, Page 1-13
DOI: 10.9734/BMRJ/2016/26138

Background: Enterotoxigenic E. coli (ETEC) is under recognized but an important cause of diarrhea in the developing countries. It is the most frequent bacterial cause of diarrhea in children and adults living in these areas but is most frequently seen in children. We aimed to determine the incidence of LT producing ETEC in cases of acute diarrhea in children under 5 years, to detect the phenotypic characters of LT producing ETEC and to investigate the presence of the heat labile toxigenicity gene in isolated E. coli strains.

Methodology: This study was carried out on 100 children with acute diarrhea. After history taking and clinical examination, diarrheal stool was used for phenotypic characterization of ETEC through isolation of E. coli by culture followed by microscopic examination then biochemical reactions using API 20 E. LT producing ETEC strains were detected using Phadebact R ETEC-LT test. Antibiotic sensitivity of the positive strains was done followed by genotypic characterization through detection of heat-labile toxigenecity gene (elt) in isolated E. coli strains by polymerase chain reaction.

Results: LT producing ETEC was isolated in (8%) of studied children with a higher sensitivity of PCR than coagglutination test. There was no significant effect on ETEC incidence regarding sex or age; it was significantly lower in breast fed infants with a seasonal peak during summer and early autumn. It showed sensitivity to ceftriaxone (87.5%) and resistance to trimethoprim-sulphamethoxazole (75%), ampicillin (62.5%) and gentamycin (50%).

Conclusion: Rapid screening test is a useful addition to laboratory diagnostic procedures in regions where ETEC is endemic. PCR has high levels of sensitivity and specificity and able of detecting both expressed and silent genes. Sensitivity of isolates to ceftriaxone (87.5%) suggests that this antibiotic is a rational choice for the treatment of prolonged childhood diarrhea in which ETEC is a primary etiologic causative agent.

Open Access Original Research Article

The Effect of E-waste Dumpsite Soil on Cultured Tilapia Fish and Associated Microorganisms

Adegunloye Deke Victoria, Sanusi Adeyemi Isaac

Microbiology Research Journal International, Page 1-12
DOI: 10.9734/BMRJ/2016/20412

Aim: To evaluate the toxicological effect of e-waste on cultured tilapia and identifying microorganisms associated with the tilapia aquaria polluted with soil from e-waste dumpsite.

Study Design: The soil samples, water from the polluted aquaria and the harvested fish were then subjected to physicochemical, microbiological, proximate and toxicological analyses.

Place and Duration of Study: Lagos State and the study were undertaken for five weeks.

Methodology: The organic contents were determined using gravimetric techniques, nitrogen content was determined using kjeldhal method, exchangeable bases were determined using flame emission spectrometry and EDTA classical methods titration, heavy metals determination were estimated using atomic absorption spectrometer, the toxicological study and the microbiological analyses were carried out using standard methods.

Results: The physiochemical parameters of the soil samples differs with higher heavy metals values in e-waste soil sample. Some of microorganisms isolated were of the genera; Bacillus, Proteus, Listeria, Pseudomonas, Lactobacillus, Aspergillus, Articolospora, Penicillium, Rhizopus, Mucor, and Zoopage. The types and number of microorganisms from the e-waste dumpsite soil, aquaria polluted with soil from e-waste dumpsite differs from those from controls. The ash content (9.68a±0.08 - 14.29e±0.51) showed improvement over the control (9.49a±0.20). Rise in fibre content of the tissue (0.86b±0.02 - 0.98c±0.01) was also observed over the control. Deformities of the gills and livers of the fish were observed while the packed cell volume, haemoglobin, oxygen carrying capacity and the red blood cell of fish from polluted aquaria were lower than that of fish from unpolluted aquaria. Immunological responses were also observed.

Conclusion: The histopathological and the haematological effects alongside the effect on the proximate composition and the microbial isolate variation in the soil samples and aquaria showed the adverse effect of the e-waste on the fish and its environment.

Open Access Original Research Article

Suppression of Phytopathogenic Fungi by Plant Extract of Some Weeds and the Possible Mode of Action

Mohamed Hashem, Saad A. Alamri, Ashia A. Shathan, Sulaiman A. Alrumman, Mahmoud F. M. Moustafa

Microbiology Research Journal International, Page 1-13
DOI: 10.9734/BMRJ/2016/26629

Aims: The goal of this work was to emulate the antifungal properties of some newly collected weeds against important phytopathogenic fungi: Pythium ultimum, Penicillium expansum and Fusarium solani. The mode of action through which the extracts could affect the target fungi was studied.

Place and Duration of Study: Department of Biology, Faculty of Science, King Khalid University, Saudi Arabia, between February, 2014 and May, 2015.

Methodology: Ten plant species were obtained from Aseer region. The plant extract obtained by ground dry plant material to be a fine powder and shaking in chloroform, ethanol or hexane. Screening of antifungal activity of the plant extracts was carried out against the phytopathogenic fungi grown on Czapek’s agar medium using disc diffusion method and the minimum inhibitory concentration was determined. The treated fungal samples were examined and photographed using the scanning electron microscope to define the alteration and malformation in the fungal hyphae. The chemical composition of the most active plant extracts was determined using gas chromatography–mass spectrometry (GC–MS).

Results: Preliminarily test of the crude extract of the weed plants showed antifungal activity against all organisms but in various extent. The crude extract of Foeniculum vulgare showed the highest antifungal activity against the three phytopathogens. Scan electron microscopy (SEM) approved a clear morphological malformation in the hyphae and spores supported the assumption that the mechanism involved in killing the fungus includes the altering of cell membrane permeability that leads to the plasmolysis of the cells and changing their shape. Gas chromatography–mass spectrometry (GC-MS) analysis results showed that many aliphatic and aromatic compounds were identified in the different extracts. The main observation was the number and types of the detected compounds have greatly depended on the type of the extract. We assume that many compounds in each extract act in synergetic effect to destruct the fungal cell integrity and involved in their death.

Conclusion: The plant extract of Foeniculum vulgare is a promising natural product that could be applied in control of many phytopathogenic fungi as an alternative to hazard chemical fungicides.

Open Access Original Research Article

Partial Purification and Characterization of a Haloalkaline Protease from Pseudomonas aeruginosa

S. Palpperumal, S. Sankaralingam, D. Kathiresan, B. Harinathan, T. Shankar, D. Prabhu

Microbiology Research Journal International, Page 1-7
DOI: 10.9734/BMRJ/2016/26289

A study was conducted to partially purify and characterize a haloalkaline protease isolated from Pseudomonas aeruginosa. The enzyme was purified in a two-step procedure involving acetone precipitation and chromatography. The enzyme was shown to have a relatively low molecular weight of 30 kDa. The haloalkaline protease enzyme was purified 2.2-fold with a relative activity of 67.25%. The maximum activity of the enzyme was noticed at 35°C at pH 9, with casein as a substrate. The partially purified enzyme was almost 100% stable at 5% sodium chloride supplemented medium even after 1hr of incubation. The effect of sodium dodecyl sulphate on partially purified protease activity revealed that the maximum activity was found to be at 50 mM. The impact of ethylene diamine tetra acetic acid on the partially purified protease activity revealed that the maximum activity was found to be at 50 mM. The compatibility of the enzyme was studied with commercial and local detergents. The partially purified enzyme has improved the sanitization power of the detergents tested.

Open Access Original Research Article

Seroprevalence of Hepatitis C Virus amongst Blood Donors in Parts of North Central Nigeria

E. I. Bigwan, H. I. Inabo, S. A. Ado, E. D. Jatau

Microbiology Research Journal International, Page 1-6
DOI: 10.9734/BMRJ/2016/26530

Background: Hepatitis C virus is one of the blood borne transmissible infections of public health significance. It can easily be transmitted to a wider population through transfusion of contaminated blood or blood products.

Aim: To determine the seroprevalence of HCV antibodies amongst potential blood donors in the study area.

Materials and Methods: Seven hundred and ten (710) samples were collected from consented blood donors in the study area and were examined for anti-HCV antibody using a third generation enzyme-linked immunosorbent assay (ELISA) Test kit (Autobio Diagnostics, China) based on the manufacturer’s instructions. Structured questionnaires were administered to the participants and results were analyzed using SPSS version, 23.0 statistical software package.

Results: Of the 710 samples of voluntary blood donors examined, 7.0% were positive for anti-HCV antibody. Male participants had a higher prevalence of 7.1% than females who had 6.7% (p= .88). The age group 41-50 years had the highest seroprevalence of 10.9%, followed by age groups 10- 20, 21-30 and 31-40 with a prevalence of 8.8%, 7.7%, 4.7% respectively ,while the age groups above 50 showed no evidence of HCV antibodies(p= .46).

Conclusion: The seroprevalence of HCV infections is evident amongst potential blood donors and this call for health care providers and policy makers to ensure that there is proper screening for HCV in all health facilities in the area before any blood transfusion in order to minimize the spread of the infection in the area and Nigeria at large.