Open Access Original Research Article

Isolation and Identification of Microbial Deteriogens of Fresh Tomatoes Stored at Ambient Temperature

G. M. Obunukwu, K. S. Dike, G. E. Nwakwasi

Microbiology Research Journal International, Page 1-8
DOI: 10.9734/MRJI/2018/45193

This study investigated the microorganisms associated with the deterioration of fresh tomato, Lycopersicum esculentum, stored at ambient temperature. A total of 60 tomatoes obtained from three different markets in Owerri metropolis, Nigeria were sampled and a total of 134 bacteria isolates and 140 fungal isolates were encountered. Bacteria isolated and identified were Bacillus spp, Pseudomonas spp, Escherichia coli, Klebsiella spp and Salmonella spp. The most prevalent bacteria isolate was Bacillus spp with 52.24% while Salmonella spp was the lowest prevailing isolate with 1.49%. The fungal isolates were Fusarium spp, Aspergillus spp, Rhizopus spp, Saccharomyces spp. Whereas Aspergillus spp was the most prevalent with 60.71% and was found in tomato sample from all the market, Rhizopus spp had the least prevalence of 0.71%. The presence of toxin producing fungi, Aspergillus spp and Fusarium spp which are capable of causing food poisoning as well as some bacterial isolates, raises concern over public health risks that may be associated with the consumption of unwholesome tomato.

Open Access Original Research Article

Monitoring Fungal Biodegradation of Low-density Polyethylene [LDPE] from Plastic Wastes Dump Sites Using FT-IR Spectra

Babatunde I. Aderiye, Richard O. Akinyeye, Adebisi Sulaimon, Olusola A. Oluwole, Fayokemi J. Kehinde, Oluwadamilola E. Ojo, Sunday O. Bamiteko

Microbiology Research Journal International, Page 1-15
DOI: 10.9734/MRJI/2018/44851

Introduction: Polyethylene is the most commonly used synthetic plastic and is poorly degraded in natural environments, thus causing serious environmental problems.

Aim of the Study: This study was designed to investigate the polyethylene degrading potentials of fungal strains recovered from several plastic polluted sites.

Place and Duration of Study: Department of Microbiology, Ekiti State University, Ado-Ekiti between January 2016 and October 2017.

Methodology: Soil and buried water sachet samples were analysed for polyethylene degrading bacteria. Their abilities were monitored using dry weight, radial mycelial growth and Fourier
transform infrared (FTIR) spectroscopy.

Results: The Ekiti State Waste Management Board site had the highest number of fungi isolates [28.75 x 104 and 16 x 104 hyphal cells/propagules per ml] obtained from the soil and polyethylene waste samples respectively. Five of the nineteen fungal isolates utilised low density polyethylene [LDPE] and were identified via molecular techniques as Aspergillus flavus KMBF 1501, Penicillium simplicissimum YK 18, Alternaria alternata strain 20UPMNR, Aspergillus sp.  and an unknown isolate Ps. 10 which could not be identified due to its low amplicon size. The FT-IR spectra revealed a carbonyl absorption band in Aspergillus flavus KMBF 1501 and Penicillium simplicissium YK 18 degraded polyethylene powder with vibration [Vfh] of C=O at 1726.35 cm-1 normally observed at the frequency range of 1750 cm-1 – 1710 cm-1 denoting the formation of ketone or aldehyde group. A new Vfh of O-H stretch with H-bonded structure at 3286.81cm-1 was formed by the degrading ability of Aspergillus flavus KMBF 1501 suggesting the formation of a new functional group usually at frequency range of 3500 and 3200cm-1 as alcohol or phenol. A slight decrease in the Vfh of O-H bend from 931.65 cm-1 to 929.72 cm-1, indicating carboxylic acid was also observed. However, a slight increase in the Vfh of C=C stretch from 1635.69 cm-1 to 1639.55 cm-1 represent an alkene while its O-H stretch gave a carboxylic acid group with no significant change when compared to the control sample.

Conclusion: The FT-IR analyses demonstrated the ability of the fungal isolates to colonise and modify LDPE films.

Open Access Original Research Article

Microbiological Quality and Shelf Life of Pickled African Walnut (Tetracarpidium conophorum) Preserved with Lactic and Citric Acids

V. C. Eze, N. Maduka, I. Ahaotu, N. N. Odu

Microbiology Research Journal International, Page 1-18
DOI: 10.9734/MRJI/2018/45226

The short shelf life of locally processed ready-to-eat African walnut is a challenge limiting its utilisation. Pickling is an ancient traditional practice of preserving certain types of food. Therefore, the addition of organic acids to African walnut pickle is aimed at elongating shelf life of the product. In this study, raw African walnut was prepared, then pickled using brine solution (5 % NaCl) that separately contain 1 %, 3 %, 5 % citric and 1 %, 3 % and 5 % lactic acid. The samples were stored for 6 Weeks at room temperature (28±2ºC). Total bacterial and fungal counts of the product were monitored weekly using standard methods. Microbiological challenge test study of the pickles using Bacillus cereus and Staphylococcus aureus isolated from fresh African walnut was also performed. Pickle without organic acid was the control sample. Using molecular identification methods, Bacillus cereus strain EV-1 (KY689737), Ochrobactrum ciceri strain EV-2 (KY689738) and Bacillus amyloliquefaciens strain EV-3 (KY689739) were isolated from the pickles. Fungi isolated were Penicillium sp. and Fusarium sp. Total bacterial and fungal count of the pickles range between 3.52-7.34 log10cfu/g and 3.48-5.73 log10cfu/g, respectively was higher than that of the control sample. Importantly, lactic acid demonstrated more antibacterial effect than citric acid in preserving African walnut pickles. The challenge test result revealed that B. cereus was more dominant than S. aureus. Based on Microbiological Guidelines for Ready-to-Eat Food that B. cereus and S. aureus must be less than 5 log10cfu/g and 4 log10cfu/g, respectively, the developed pickle is best consumed within 2 weeks.

Open Access Original Research Article

Review on Emerging and Reemerging Infectious Diseases and Their Origins

M. S. Abdallah

Microbiology Research Journal International, Page 1-5
DOI: 10.9734/MRJI/2018/39953

Emerging infectious diseases are diseases with an incidence rate that increased in the past 20 years and could increase in the near future. There are two categories of infectious diseases namely; emerging and reemerging infectious diseases. As such, are diseases that are recognized in the human host for the first time and diseases that historically have infected humans, but continue to appear in new locations or drug-resistant forms. Certain factors resulted in the emergence of emerging and reemerging infectious diseases, which include; ecological factors, human demographic changes and behaviour; travel and commerce; as well as; technology and industry. Moreover, they are also widespread in the universe despite the awareness of preventive measures across the globe.

Open Access Original Research Article

Evaluation of MecA Gene Occurrence of Gram Positive Bacteria Isolated from Patients with Otitis

Ömer Akgül, Yunus Çetin, Gülhan Bora, Yaser Çetin, Müzeyyen Kaya

Microbiology Research Journal International, Page 1-8
DOI: 10.9734/MRJI/2018/45565

Otitis externa (OE) and Otitis media (OM) are two important diseases that affects a significant portion of the communinities in developing countries. The prevalance of otitis media and externa in Easthern Turkey, the proportion of the implicated bacteria that are Gram positive, and their antibiotics resistance profiles was investigated in this study. Ear swab samples were collected from 2000 patients (1000 women and 1000 men) at the Van Training and Research Hospital Department of Otorhinolaryngology, Turkey. The Patients were between the ages of 0 to 80 years. Microbiological analysis was carried out on the samples in the Pharmaceutical Microbiology laboratory, Faculty of Pharmacy, Van Yüzüncü Yıl University, Turkey. The presence of Gram positive bacteria was observed in 1,225 ear swab samples. Staphylococcus aureus was found to be the most common isolated bacterium in male and female patients with otitis. Streptococcus pyogenes and Streptococcus pneumoniae were the second most common isolated bacteria, respectively, in male and female patients with otitis. Gram positive bacteria isolated from male patients with otitis showed the highest resistance to Cefoxitin, while those isolated from female patients with otitis showed the highest resistance to Erythromycin. Oxacilin resistance was determined for of the S. aureus isolates, of which 22 were from the male patients and 14 from the female patients. According to the results of Polymerase Chain Reaction (PCR) the 36 isolates were positive for mecA gene. It is thought that the data obtained from this study will contribute to the elaboration of OE and OM diseases in the Easthern Region of Turkey.