Open Access Original Research Article

Molecular Screening of Fungal Isolates of Palm Oil from South Eastern Nigeria for Aflatoxin and Ochratoxin Biosynthetic Genes Using Multiplex Polymerase Chain Reaction (mPCR)

I. N. Nwachukwu, E. S. Amadi, U. C. Ogwo, S. I. Umeh, C. C. Opurum, E. C. Chinakwe, N. U. Nwaogwugu, I. E. Ochiagha, H. D. Ogbuagu, F. N. Ujowundu

Microbiology Research Journal International, Page 1-9
DOI: 10.9734/mrji/2019/v28i530142

In Nigeria and many other developing countries of the world, the incidence of mycotoxin- contamination of foods and food products has attracted attention and stirred a lot of concern for food safety. This work aims at detection of aflatoxigenic and ochratoxigenic synthetic genes from fungal isolates of palm oil as a veritable means for the evaluation of foods for possible mycotoxin contamination.  In this study, fungal isolates from palm oil samples collected from the five states of South-east geopolitical zone in Nigeria were screened for  aflatoxin and ochratoxin biosynthetic genes using Multiplex Polymerase Chain Reaction (mPCR). The assay relied on three sets of primers that amplify aflatoxgenic Aspergillus, ochratoxigenic Aspergillus and Penicillium species under optimized PCR conditions. Optimum multiplex PCR assay was standardized for simultaneous detection of toxigenic Aspergillus and ochratoxin producing Penicillium species targeting AflR, AflS and pks genes involved in aflatoxin and ochratoxin metabolic pathways respectively. AflR primer pair gave specific amplification for aflatoxigenic A. flavus but did not give amplification for A. niger and P. chrysogenum. While AflS and pks gave amplification for only aflatoxigenic and ochratoxigenic A. niger and P. chrysogenum. In the evaluation and monitoring of mycotoxin-producing fungi during the processing of food and feed commodities, Multiplex PCR approach could be a veritable tool to supplement the conventional analytical techniques.

Open Access Original Research Article

Molecular Detection of Methicillin Resistance Genes from Clinical Sources and Hospital Environments

O. C. Adekunle, T. O. Oyakeye, Y. O. Adesiji

Microbiology Research Journal International, Page 1-7
DOI: 10.9734/mrji/2019/v28i530143

Infections associated with Staphylococcus aureus have high mortality rate and lead to economic loss with a long stay in the hospital. Methicillin-resistant S. aureus (MRSA) is one of the major nosocomial pathogens which are acquired in the health care facilities.  The objective of the study was to investigate the presence of MRSA in clinical sources and hospital environments. Samples were collected, cultured and identified. Also, the antibiotic susceptibility profile was done. Polymerase chain reaction (PCR) amplification of identification gene nuc- and the resistant gene, mecA were conducted. Sixty-three isolates were positive for S. aureus out of 370 clinical samples (urine, wound, nasal swabs and pus) and 37 positives out of 262 samples from hospital environments. Majority of the isolates were sensitive to cefoxitin, novobiocin and majority were resistant to ceftazidine, cloxacillin and augmentin. Seventy-one to ninety- five percent and 51-72% exhibited multi-drug resistance among clinical samples and hospital environments respectively. Both samples were positive for nuc and mec A genes. The detection of MRSA in hospital environments may pose a great danger to patients especially those of compromised status.

Open Access Original Research Article

Chronic Osteomyelitis among Children Attending Orthopedic Services at Mbarara Regional Referral Hospital: Prevalence, Etiological Agents and Their Drug Susceptibility Patterns

Tayebwa Edson, Kisitu Kyengera, Baguma Andrew, Bazira Joel

Microbiology Research Journal International, Page 1-14
DOI: 10.9734/mrji/2019/v28i530144

Background: This cross-sectional study was conducted to determine prevalence, causative agents and their drug susceptibility patterns of chronic osteomyelitis children among 766 children attending orthopedic services at Mbarara Regional Referral Hospital between October 2016 and June 2017.

Methods: Seventy-four consented patients were consecutively enrolled and their demographic characteristics, clinical and radiological data collected. Superficial and deep bone pus swabs were collected and processed as per standard operative procedures. Susceptibility testing was done using the Kirby Bauer disc diffusion technique. Data was analyzed using Stata version 13.0.

Results: The prevalence of children with COM was 9.7%.  The female: Male ratio was 1:1.2 with a mean age of 11 years. The most infected bone was the tibia followed by the femur. The common clinical presentations were chronic bone pain and discharging sinus tracts whereas the most imminent radiological features were sequestrum and involcrum. Pus swabs were taken off from both the discharging sinuses and the deep intra osseous abscesses for culture and sensitivity studies. The concordance rate of the microorganisms between the superficial and the deep swabs was 62.5%. Staphylococcus aureus was the most predominant microorganism isolated (85%). All the microorganism isolates were sensitive to gentamycin. However, all Staphylococcus aureus isolated were resistant to penicillin.

Conclusion: Prevalence of Chronic osteomyelitis among children with orthopedic conditions presenting to MRRH is high. The isolated microorganisms are resistant to antibiotics we commonly use in our settings.

Open Access Original Research Article

Comparative Efficacy of Different Brands of Baker’s Yeast Used in Bread Production in Jos Metropolis, Nigeria

A. I. Onaji, B. E. Agbo, R. A. Asiru, Tarfena, Yoila Amapu

Microbiology Research Journal International, Page 1-6
DOI: 10.9734/mrji/2019/v28i530145

Consumption of bread and other baked aerated wheat flour products has spurred the needs to determine the leavening ability of different brands of baker’s yeast used in bread production. In this study we assessed the leaving ability of different brands of baker’s yeast in production of quality bread and the flour used in baking test was Dangote flour. Seven brands of different commercial baker’s yeast were collected from the 13 different brands sold in Jos market. These brands includes: Angel instant active dry yeast (ANGY), Saf-instant active dry yeast (SAFY), Food mont instant active dry yeast (FOMY), Pasha instant active dry yeast (PASY), STK- Royal active dry yeast (ROYA), Vahine active dry yeast (VAHY) and Fermipan active dry yeast (FEMY). The results of the viability tests for the different brands of active dry yeast indicated that six out of the seven brands were 100% viable while one had only one dead cell. Statistical analysis (one-sample-t- test) revealed that there was significant different among the different brands of yeasts used (p<0.05), however ANGY had the highest performance viability (p<0.002) and PASY had the least (p<0.039) as shown in Table 3 in appendix. The result of the pH variation as function of time at 260C shows steady decrease in pH values of all the different brands of yeast suspension. Using regression analysis, pH at 150 minutes contribute  96 percent to the leavening ability of different brands of baker’s yeast used in  bread production and 30 minutes contribute the lowest 9.1 percent as shown in the Table 4 in the appendix. It was concluded that all the seven brands of baker’s yeast tested were suitable for use in bread production when compared with the standard.

Open Access Original Research Article

Flocculating Properties of a Bioflocculant Purified from Bacillus Subtilis Isolated from the Stream Sediments of Onyearugbulem Market, Akure, Nigeria

F. O. Ekundayo, F. B. Omiyale, E. R. Omomo

Microbiology Research Journal International, Page 1-16
DOI: 10.9734/mrji/2019/v28i530146

Soil samples (sediments of stream, its bank and abattoir soil) were collected from Onyearugbulem market abattoir, Akure, Ondo State, Nigeria. Bacteria were isolated from the above soil samples by dilution and pour plate methods. Screening for best bioflocculating bacteria was also performed. Effects of metal ions (such as Mg2+, Ca2+ and Al3+), temperature and pH on flocculating activities of the bioflocculant were also determined. Six bacterial isolates producing flocculating substances were isolated and the isolate with the best flocculating property was selected. The identified bioflocculant producing bacteria are Bacillus anthracis, B. subtilis, B. thuringiensis, B. cereus, Streptomyces griseus and S. somaliensis. The best bioflocculant producing bacterium was Bacillus subtilis and the flocculating activity of its bioflocculant was stimulated in the presence of Mg2+, Ca2+and Al3+. This bioflocculant was thermostable and retained more than 80% of its flocculating activity after being heated at 100ºC for 25 minutes. It had the highest flocculating activity of 85% at pH 6 with optimum bioflocculant dosage of 0.8 mL. This study suggests soil samples from Onyearugbulem market abattoir as a potential source of bioflocculant-producing bacteria with good bioflocculating properties.