Open Access Short Research Article

Detection of Carbapenem Resistance in Salmonella Species from a Tertiary Hospital in Eastern Cape, South Africa

M. A. Bisi-Johnson, C. L. Obi

Microbiology Research Journal International, Page 1-6
DOI: 10.9734/BMRJ/2015/18586

Aims: Broad-spectrum carbapenem group is the current therapy for strains of Enterobacteriaceae that express extended spectrum beta-lactamases (ESBLs). However, recent reports of therapeutic failures of carbapenems with strains that produce multiple β-lactamases are being documented. This study profiled antibiotic resistance in clinical isolates of Salmonella species in a tertiary hospital in the Eastern Cape of South Africa with the aim of identifying the status of Salmonella therapy in the region.

Study Design: This is an analytical study.

Place and Duration of Study: Salmonella isolates (119) from 96 blood and 23 stool specimens of patients attending Nelson Mandela Academic Hospital Complex (NMAHC) and surrounding clinics, Eastern Cape, South Africa collected for surveillance purposes over a period of 3 years (2006 – 2009) were obtained from National Institute of Communicable Diseases, (NICD), for analysis between 2010 and 2011.

Methodology: Preliminary identification and serotyping were done at the NICD. The identification and antimicrobial susceptibility profile of isolates were confirmed with an Autoscan-4 antimicrobial susceptibility system. The MIC of ertapenem and imipenem tested for all Salmonella spp. were ≥2 mg/L and ≥4 mg/L respectively.

Results: A considerable portion of the isolates 59/119 (49.6%) showed pentavalent resistance to some antibiotics including ampicillin and amoxicillin. Of the 59 multiply resistant isolates, 14 (23.7%) were resistant to 1 or more of the carbapenems examined. The phenotypic determination of ESBLs resulted in 25 (21.0%) ESBL-positive Salmonella isolates. Using Fisher's exact test, the proportion of carbapenem resistance isolates was significant at P value 0.032.

Conclusion: The growing resistance of Salmonella isolates to carbapenem drugs in this setting call for caution in usage since this is a pointer to fewer options in the choice of drugs for ESBL’s therapy. Contact precautions should be put in place to forestall further transmission.


Open Access Original Research Article

Detection of Virulence Genes in Staphylococcus aureus and Streptococcus agalactiae Isolated from Mastitis in the Middle East

Ayman El-Behiry, Mohamed Elsayed, Eman Marzouk, Yaser Bathich

Microbiology Research Journal International, Page 1-9
DOI: 10.9734/BMRJ/2015/19237

Aims: The current study was carried out to genotypically characterize Staphylococcus aureus (S. aureus) and Streptococcus agalactiae (S. agalactiae) isolated from clinical and subclincal cases of bovine mastitis.

Study Design: The S. aureus and S. agalactiae strains were characterized phenotypically, and were further characterized genotypically by polymerase chain reaction (PCR) using oligonucleotide primers that amplified genes encoding the fibronectin-binding proteins A (fnbA), the clumping factors A (clfA), the surface protein A (spa) and the coagulase (coa) genes for S. aureus and the surface immunogenic protein (sip), hyluronidase (hyl), CAMP factor (cfb), surface enzyme (scpB), β-hemolysin/cytolysin (cylE) and alpha-C-protein (bca) for S. agalactiae.

Place and Duration of Study: A total of 61 S. aureus and 43 S. agalactiae isolates were obtained from milk samples collected from 160 apparently healthy cows and 54 clinical cases during a survey conducted for six months at different localities in El-Behira province, Egypt and Al-Qassim region, Kingdom of Saudi Arabia.

Results: 59 (~97%) of S. aureus isolates illustrated a positive coagulase-test and 100% were positive when tested with the BBL™ Staphyloslide™ Latex. All identified strains of S. aureus were PCR positive for thefnbAclfAspa (x-region) and spa (IgG Binding region) genes which displayed a single size amplicon of approximately 1226 bp (73.77%), 1000 bp (88.52%), 500 bp (80.32%) and 300 bp (19.67%), respectively. In contrast, the amplification of the coa-gene exhibited three dissimilar size polymorphisms with around 500 bp (57.37%), 600 bp for (8.19%) and 900 bp (8.19%). Furthermore, 42 (~98%) out of 43 S. agalactiae isolates were positive by agglutination of the blue latex particles within 20 second in the test circle and 100% demonstrated a positive results in the CAMP test. All confirmed S. agalactiae isolates were also PCR positive for the sip gene (90.69%), hyl gene (81.39%), cfb gene (93.02%), cylE gene (90.69%), scpB gene (67.44%) and bca gene (20.93%).

Conclusion: The high frequency of virulence genes detected in the current study will help in the understanding of the distribution of infectious S. aureus and S. agalactiae strains in the Middle East and contribute to the establishment of preventive approaches to reduce the spread of infection.


Open Access Original Research Article

Prevalence of Multidrug Resistant Bacteria Isolated from Biomedical Waste Generated in Makurdi Metropolis, Benue State, Nigeria

V. T. Omoni, O. A. Makinde, S. O. Abutu

Microbiology Research Journal International, Page 1-10
DOI: 10.9734/BMRJ/2015/17384

Multiple drug resistance bacteria in solid and liquid wastes in public and private hospitals were investigated between December, 2013 and February, 2014. Solid and liquid wastes were collected from discharged sites from different wards of both hospital environments. The antibiotic susceptibility patterns of the different isolates to commonly used antibiotic using multi-antibiotic disc at different concentrations were determined. A hundred and twenty-four bacterial isolates were identified from the collected samples, 36 (29.0%) and 88 (70.9%), of which were from liquid and solid wastes respectively. The bacteria isolated were Escherichia coli (E. coli) 23 (18.6%), Staphylococcus aureus 20 (16.1%), Enterobacter sp 18 (14.5%), Pseudomonas sp 15 (12%), Proteus sp 12 (9.7%), Shigella sp 11 (8.9%), Klebsiella sp 8 (6.5%), Salmonella sp 7 (5.7%), Bacillus sp 5 (4.0%), Citrobacter sp 3 (2.4%), and Serratia sp 2 (1.6%). The results showed that E. colihad the highest percentage of 18.6%; followed by Staphyloccocus aureus (16.1%) from the total number of bacterial species identified from the solid and liquid wastes. Serratia sp had the least percentage of 1.6% and Citrobacter sp with 2.4%. E. coli were 100% resistant to ciproflox and ampicillin while Klebsiella pneumoniae and Shigella sp were highly resistance to ampicillin with 87.5% and 81.8%, respectively. Among the gram-positive isolates, Staphylococcus aureus was found to be resistant to floxapen (70%) followed by erythromycin (60%) while Bacillus sp was resistant to erythromycin (80%), norfloxacin (60%) and floxapen (60%). The studied area showed high occurrence of multiple drug resistance patterns in both the public and private hospitals to the commonly used antibiotics tested on the isolated organisms.


Open Access Original Research Article

Prevalence and Diversity of Coliphages in Dhaka, Bangladesh and Their Lytic Potentials against Pathogenic Bacteria

Saadlee Shehreen, Ruhul H. Kuddus, Md. Aftab Uddin

Microbiology Research Journal International, Page 1-11
DOI: 10.9734/BMRJ/2015/20392

Aim: Dhaka is a flood-prone city with a high prevalence of diarrhoeal diseases. This study investigated the natural reservoirs and diversity of coliphages in Dhaka to establish phage strains of potential use in antidiarrhoeal therapy.

Materials and Methods: 296 surface water samples and 20 faecal samples of hospitalised diarrhoea patients were collected during April-September 2012 and phages isolated were used in infecting 67 strains of Escherichia coli, 20 strains of Shigella sp., and 10 strains of Vibrio cholerae. Phage isolates were grouped by plaque morphology and representative morphotypes were characterised by restriction fragment length polymorphism (RFLP) analysis and Southern blot hybridisation.

Results: Bacteriophage diversity and titers were higher during the beginning of the flood season (June-August) and lower in other months (April, May, and September), indicating that seasonal run-off affects phage diversity and abundance. The 98 phage isolates fell into nine distinct morphotypes designated as coliphage-Dhaka (CPD) 11-19. Host range, RFLP patterns, and the estimated genome size indicated that the morphotypes were distinct except that CPD13 and CPD19 have identical RFLP pattern. Southern blot analysis indicated that all the morphotypes except CPD14 and CPD15 are genetically related. A colony blot hybridisation screening of 500 different colonies of 97 different strains of three different bacterial species indicated that none of the phage isolates is lysogenic. Lytic infection of the 87 bacterial strains indicated that most morphotypes have a limited host range except CPD12 and CPD15. These two morphotypes infected and lysed 30-70% of the test bacterial strains.

Conclusions: Of the nine coliphage morphotypes characterised in this study, CPD12 and CPD15 have the potentials for developing therapeutic phage strains.


Open Access Original Research Article

Proximate and Anti-nutrient Contents of Kersting’s Groundnut (Macrotyloma geocarpum) Subjected to Different Fermentation Methods

C. Abiola, V. O. Oyetayo

Microbiology Research Journal International, Page 1-10
DOI: 10.9734/BMRJ/2015/19735

Aim: The study aimed to ascertain the effect of different fermentation methods and time on the proximate and reduced the anti-nutrient contents Kersting’s groundnut (Macrotyloma geocarpum).

Design of the Study: A comparative effect of different fermentation methods on the proximate and anti-nutrient content was evaluated.

Place and Duration of Study: Department of Microbiology and Central Science Laboratory, Federal University of Technology, Akure, Nigeria, between March 2013 and June 2014.

Methodology: The seeds were de-husked and sorted to remove extraneous matters. Liquid and solid fermentation were carried out using standard analytical methods. The proximate and anti-nutrients (trypsin inhibitor, tannin, oxalate, phytate) of the fermenting samples were analysed every 24 h during fermentation.

Results: Proximate analysis revealed that moisture content significantly (P=0.05) decreased from 6.25±0.14% to 4.69±0.06% and 4.89±0.02% after 24 h of liquid and solid fermentation respectively. Liquid fermentation significantly (P=0.05) increased the protein content of the groundnut from 18.11±0.50% to 21.10±0.49% and 22.47±0.48% after 24 h and 48 h respectively. No significant difference (P=0.05) was observed after 72 h of fermentation. While solid fermentation significantly (P=0.05) increased protein content from 18.11±0.50% to 19.08±0.01% after 72 h. Both fermentation methods significantly (P=0.05) reduced crude fibre and increased fat content respectively. Soluble carbohydrate decreased significantly (P=0.05) from 63.72±0.39% to 58.17±0.87% after 48 h of liquid fermentation. Anti-nutrient (trypsin inhibitor, tannin, oxalate and phytate) contents decreased significantly (P=0.05) more in liquid state fermentation than in solid state fermentation. Trypsin inhibitor unit significantly (P=0.05) reduced from 72.18±0.00 mg/g to 12.28±0.38 mg/g and 24.17±0.01 mg/g after 24 h of liquid and solid fermentation respectively. However, a significant (P=0.05) increase was observed in trypsin inhibitor content after 48 h of both fermentation methods.

Conclusion: The research has revealed that 24 and 72 h liquid and solid fermentation of Kersting’s groundnut significantly (P=0.05) enhanced the proximate content. The anti-nutrient contents also reduced significantly (P=0.05) in liquid fermentation.


Open Access Original Research Article

In vitro Investigation of Antimicrobial, Antitumor and DPPH Reduction Capacity of the Methanolic Extract of Scoparia dulcis

A. K. M. Riasat-ul-Islam, Prawej Ansari, Awale Yusuf Mousa, S. M. Nazmul Haque, Nasrin Sultana, Md. Nasir Uddin, Mahmuda Sultana

Microbiology Research Journal International, Page 1-9
DOI: 10.9734/BMRJ/2015/19437

Scoparia dulcis belongs to the family Plantaginaceae. It is a flowering plant and locally common in the treatment of gastrointestinal upset and malaria. The aim of this study was to investigate the antimicrobial, antitumor and antioxidant activity of methanolic leaf extract of S. dulcis. The DPPH free radical scavenging assay was used to evaluate antioxidant property. The disk diffusion method and brine shrimp lethality bioassay were used to determine antibacterial and cytotoxic activity, respectively. In the evaluation of antioxidant property IC50 was found to be 196.66 µg/ml, in cytotoxicity testing, it was found that the plant extract has 29.868 µg/ml of LC50. The methanolic extract of S. dulcis leaves also have efficiency in bacterial growth inhibition; this extract is effective against both gram negative and positive bacteria. The zones of inhibition at 500 µg/ml dose in E. coli and S. aureus culture were 20 mm and 22 mm, respectively. In thin layer chromatography analysis, presence of non-polar and polar compounds, three non-chromatophoric compounds were found. We conclude that the S. dulcis is a potent antibacterial, antioxidant and cytotoxic medicinal plant.