Open Access Minireview Article

Foodborne Diseases and Intoxication in Nigeria: Prevalence of Escherichia coli 0157:H7, Salmonella, Shigella and Staphylococcus aureus

Samuel Ekene Odo, Chidiebere Francis Uchechukwu, Ugochi Rita Ezemadu

Journal of Advances in Microbiology, Page 84-94
DOI: 10.9734/jamb/2020/v20i1230312

The prevalence of foodborne diseases in Nigeria is alarming despite efforts by Government and Non-governmental Organizations to prevent the spread of foodborne pathogens. Health and socio-economic implications of foodborne diseases are enormous, including loss of productivity and low quality of life. In Nigeria, most people eat food at least once outside their homes every day. Food is an indispensable basic need of all humans and animals to sustain a healthy, reproductive and productive life. Humans are very active and highly productive when they consume safe food and are in a state of good health; however, consuming food already contaminated with microbial pathogens or its products such as Escherichia coli  0157:H7, Salmonella spp., Shigella spp., Clostridium spp., Campylobacter spp., and Staphylococcus aureus-toxin to a harmful level can cause severe illnesses and even progress to death. Therefore, it is essential for food handlers and vendors to maintain proper personal hygiene, undergo regular health checks, constantly improve environmental sanitation and adequately prepare food to prevent the spread of foodborne diseases. Consumers of ready-to-eat foods and food products should consider the overall safety of the food; environment where the food was prepared, where and how the food is distributed in order to mitigate likely foodborne infections and diseases. Water used in preparing food and watering animals should be clean and safe.

Open Access Original Research Article

Percentage Bioremediation Assessment of Spent Mushroom Substrate (SMS) and Mucor racemosus in Hydrocarbon Contaminated Soil

D. N. Ogbonna, S. A. Ngah, R. N. Okparanma, O. Ule, R. R. Nrior

Journal of Advances in Microbiology, Page 1-21
DOI: 10.9734/jamb/2020/v20i1230305

Aim: The aim of the study was to assess Percentage Bioremediation of Spent Mushroom Substrate (SMS) and Mucor racemosus in hydrocarbon contaminated soil

Place and Duration of Study: A portion of Rivers State University demonstration farmland in Nkpolu-Oroworukwo, Mile 3 Diobu area of Port Harcourt, Rivers State was used for this study. The piece of land is situated at Longitude 4°48’18.50’’N and Latitude 6o58’39.12’’E measuring 5.4864 m x 5.1816 m with a total area of 28.4283 m2. Bioremediation monitoring lasted for 56 days, analysis carried out weekly (per 7 days’ interval).

Methodology: Five (5) experimental plots employing the Randomized Block Design were used each having dimensions of 100 x 50 x 30 cm (Length x Breadth x Height) = 150,000cm3. Baseline study of the uncontaminated and the deliberately contaminated agricultural soil was investigated for its microbiota and physico-chemical properties. Two of these plots were designated as pristine (Unpolluted soil) (CTRL 1) and crude oil contaminated soil without nutrient organics and bioaugmenting microbes (CTRL 2); these two serve as controls. Each of the experimental plots, except the control (CTRL 1), was contaminated with 2500 cm3 (2122.25 g) of crude oil giving initial Total Petroleum Hydrocarbon (TPH) value of 8729.00 mg/kg. The crude oil polluted soil in Plot 3 was further treated with 750 ml of Mucor racemosus broth (CS+Muc), Plot 4 was treated with 3000 g of Spent Mushroom Substrate (CS+SMS) while plot 5 was treated with the combination of both (CS+Muc+SMS). The plots were left for 7 days to ensure even distribution and soil-oil bonding. Sampling was done at seven-day interval (Day 1, 7, 14, 21, 28, 35, 42, 49, 56).  Physicochemical parameters monitored were pH, Temperature, Nitrogen, Phosphorus, Potassium, and Total Petroleum Hydrocarbon (TPH) throughout the experimental period. Microbial parameters monitored were Total Heterotrophic Bacteria (THB), Total Heterotrophic Fungi (THF), Hydrocarbon Utilizing Bacteria (HUB) and Hydrocarbon Utilizing Fungi (HUF). Percentage (%) Bioremediation was estimated from percentage (%) reduction of Total Petroleum Hydrocarbon (TPH) from day 1 to day 56 in relation to control plots.  Net % Bioremediation were also assessed to ascertain the actual potential of treatment agents singly or combined.

Results: Total Heterotrophic Bacteria (THB) (CFU/g) recorded on day 7 and day 56 of the bioremediation were; day 7; CTRL 1 – US (1.07 x109), CTRL- CS (5.4 x108), CS+Muc (3.0 x108), CS+SMS (4.6 x108) and CS+Muc+SMS (5.0 x108). On day 56, data obtained were CTRL 1 –US (9.4 x108), CTRL 2 –CS (7.2 x109), CS+Muc (3.7 x108), CS+SMS (8.1x108) and CS+Muc+SMS (6.8 x108). The increase in number in the treated plots is a depiction of an increase in activity of the organism and the stimulating effect of bio-organics SMS while the untreated plot CTRL 1-US showed decrease in population at day 56. Similar trend showed for Total Heterotrophic Fungi. Generally, it was observed that the highest growth/ count was recorded at the 7th and 8th week (day 42 or day 49), at the 9th week there was an observable decrease; probably due to depletion of nutrients and other factors such as rainfall and seepage. The Net Percentage Hydrocarbon Utilizing Bacteria and Fungi (Net %HUB and Net %HUF) were highest in Crude Oil contaminated plot treated with Spent Mushroom Substrate (SMS) singly; that is (CS+SMS) (11.02% and 12.07%) and lowest in the uncontaminated soil – Control (CTRL 1 –US) (5.41% and 9.26%) respectively. The trend in decreasing order of Net % Hydrocarbon Utilizing Bacteria were as follows: CS+SMS (11.02%) > CS+Muc+SMS (10.14%) > CS+Muc (9.43%) > CTRL 2 –CS (8.1%) > CTRL 1 –US (5.41%) while Net % Hydrocarbon Utilizing Fungi followed similar trend and were: CS+SMS (12.07%) > CS+Muc+SMS (11.76%) = CS+Muc (11.76%) > CTRL 2 –CS (11.05%) > CTRL 1 –US (9.26%). Evaluation of Amount of Crude Oil or Hydrocarbon remediated and Net %Bioremediation revealed Crude Oil contaminated plot augmented with Mucor racemosus broth singly (CS+Muc) as having the highest bioremediation potential while the least is the untreated soil. The trend is as follows:  CS+Muc (8599.19 mg/kg; 33.93%) > CS+Muc+SMS (8298.95 mg/kg; 32.74%) > CS+SMS (8197.03 mg/kg; 32.34%) > CTRL 2 –CS (166.54 mg/kg; 0.66%) > CTRL 1 –US (85.48 mg/kg; 0.34%)

Conclusion: This shows that a single nutrient substrate or augmenting microorganism applied appropriately may have a more positive result, that is; higher bioremediation potential than combined or multiple mixed treatments. It was further observed that microbial counts decreased with time in treatments with augmenting organisms alone but increased considerably in treatments supplement with organics having its peak on the 49th day.   It is therefore recommended that bioremediation of crude oil-polluted soil using bio-augmenting microorganism should be applied appropriately noting the volume: area ratio and be supplemented with efficient nutrient organics after every 49-day interval.

Open Access Original Research Article

Assessment of Physicochemical and Microbiological Quality of Table Water Sold in School Campuses of the University of Port Harcourt, Nigeria

Stephenson Danagogo Lawson, Abiye Anthony Ibiene, Victoria Amadi, Stella Ogbonnie Enyinnaya, Lasbry Chidi Nnodim, Gift Atumatuchukwu Uzah

Journal of Advances in Microbiology, Page 22-33
DOI: 10.9734/jamb/2020/v20i1230306

Water is the elixir of life which is essential for proper metabolic processes to take place. The quest for cheap and readily available source of potable water has led to the emergence of sachet and bottle water which the sale and consumption continue to grow astronomically and rapidly in most countries of the world. This study was aimed at assessing the microbial and physicochemical water quality of table water sold on School campuses. Standard microbiological procedures were used to isolate and identify various microbial genera associated with the water samples using morphological, microscopic and biochemical characterization method. The bacterial genera identified were Escherichia sp., Streptococcus sp., Micrococcus sp., Vibrio cholera., Staphylococcus sp. and Bacillus sp. with Choba campus having the highest microbial contamination of packaged water. However, the results of the physicochemical properties from this study were all below the WHO recommended limits. The temperature and pH ranged between 26-27°C and 6.98-7.08, respectively. The values of the electrical conductivity ranged from 0.080 to 0.150 µs/cm; turbidity ranged between 0.40-1.40 NTU; chloride ranged between 1.187-2.103 mg/l, nitrate was within the range of 0.01 to 0.14 mg/l; BOD ranged from 0.02-0.04 mg/l, COD was between 0.00-0.08 mg/l and the total soluble solids were between the ranges of 0.04-0.10 mg/l. Therefore, this study suggests the improvement of water-borne disease preventive and control measures, and monitoring of water quality by the regulatory agencies to ensure good manufacturing practices by the water bottling companies which will result in reduction of health hazards associated with water borne diseases.

Open Access Original Research Article

Citric Acid Production from Waste Substrate by Using Some Fungi

Shrishti Sharma, Suruchi Parkhey, Ashish Saraf, Sachin Das

Journal of Advances in Microbiology, Page 34-56
DOI: 10.9734/jamb/2020/v20i1230307

Citric acid is one of the most commonly used and easily available multifunctional organic acids. This is widely used in different industrial applications. Citric acid is 2hydroxyl 1,2,3 propanetricarboxylic acid. It is present in many fruits and vegetables. Citric acid is usually found in lemon. The global demand for Citric acid is about 6.08x105per year its uses are increasing day by day. Aspergillus niger and Aspergillus flavus organisms are used for citric acid production. In this present study citric acid production from the different waste substrates such as Banana peels, Coconut husk, and Rice straw were carried out using Aspergillus niger and Aspergillus flavus isolated from soil sample. Characterization and identification were done with the help of microscopic examination based on lactophenol cotton blue staining. Aspergillus niger and Aspergillus flavus are appeared as branched hypae with conidial spore. The production of citric acid was performed by solid state fermentation and estimated on the different fermentation days, different pH and different concentration of substrate. We observed that high level of citric acid production was on 9th day of fermentation as compared to others days of fermentation.

Open Access Original Research Article

Changes in Acid-pH Resistance of Food Spoilage and Pathogens Spore-Forming Bacteria in Cameroonian Indigenous Sorghum-Based Acidic Beers before and after Sublethal Thermal Stresses

James Ronald Bayoï, Roger Djoulde Darman, Francois-Xavier Etoa

Journal of Advances in Microbiology, Page 57-69
DOI: 10.9734/jamb/2020/v20i1230308

Fermented alcoholic beverages play a major role in the socio-cultural lives of people of Northern Cameroon. However, reports of shelf-life and health problems associated with indigenous sorghum-based alcoholic beverages are a major call for concern. This study aimed to highlight the additional effects of sublethal temperatures (no thermal treatment and 10, 45, 50 and 60°C for 45, 90, 180 min) and acidic pH of beers (2.79 and 2.63 for 45, 90, 180 min) on fate of four food spoilage and pathogens spore-forming bacteria. The experiments were carried out on real food products formed by two indigenous sorghum-based alcoholic beverages. Pasteurized traditional beers were significantly efficient on all unstressed bacterial spores after 180 minutes of treatment. In addition, spores of B. megapterium and G. stearothermophilus were more sensitive in white beer pH 2.79 and red beer pH 2.63 respectively. Previous thermal treatments of spores at certain sublethal temperatures have significantly (P=0.05) decreased the effect of both acidic beers on stressed spores. It was noticed that the spores of B. subtilis  stressed at 10°C, G. stearothermophilus (former Bacillus stearothermophilus) spores submitted at 45°C and the spores of B. cereus thermally stressed at 50°C and 60°C for 45, 90, 180 minutes were significantly (P=0.05)  less affected by the white beer at pH 2.79. Whereas, in the red beer at pH 2.63, the spores of B. subtilis sublethally stressed at 10°C and the spores of B. cereus stressed at 45°C, 50°C and 60°C were more acid resistant and very weakly affected by acid pH of the alcoholic beverages. The study delivered some overview on the potential microbial (stability and safety) consequences of the current tendency towards milder cold and heat treatments which are greatly used in the food-grade industry.

Open Access Original Research Article

Salmonella Serotypes Isolated from Beef Carcass Samples from Eswatini

B. N. Dlamini, C. Mudyanavana, T. H. Gadaga, M. T. Masarirambi

Journal of Advances in Microbiology, Page 70-76
DOI: 10.9734/jamb/2020/v20i1230309

Aim: The objective of this study was to determine the prevalence of Salmonella serovars isolated in beef carcasses slaughtered in Eswatini from 2017 to 2020.

Methods: Data analysed was officially recorded microbiological data from 2017 to 2020. Sterile broth moistened swabs were used aseptically to obtain carcass swab samples by using the non-destructive carcass sampling method. The method required that bacteriological sampling of carcasses be undertaken in the slaughterhouse without obtaining pieces of tissue samples from the sampling sites.

Results: A total of 1095 swab samples were analysed for Salmonella spp. A total of 25 Salmonella serovar isolates were identified during the study period. The predominant serovar was Salmonella Shwarzengrund (N=14; 56%). The second most frequently detected serovar was Salmonella Heidelberg (N=5; 20%). In addition, six other serovars were isolated and identified on carcasses. Each with a mean frequency of occurrence on the carcasses of N=1(4%).

Conclusion: This preliminary study has shown that various Salmonella serovars are present on beef carcasses slaughtered in Eswatini. About 25 Salmonella serovars were detected during the study period with the most prevalent being S. shwarzengrund and S. heidelberg. It is recommended that further studies should be carried out to determine the antimicrobial resistance of Salmonella strains on beef carcasses in Eswatini.

Open Access Original Research Article

Comparative Study on Effectiveness of Commercial Antibiotic Discs in Federal Capital Territory (FCT), Nigeria

Mercy I. Aboh, Yakubu Ya’aba, Shehu B. Mohammed, Peters O. Oladosu

Journal of Advances in Microbiology, Page 77-83
DOI: 10.9734/jamb/2020/v20i1230311

Clinically, antimicrobial susceptibility testing results provide guidance in the choice of antimicrobial agents in patient care. The accuracy of results from antimicrobial susceptibility testing can be affected by multiple factors including the media, antimicrobial discs or preparations, inoculum’s size, plate reading and incubation conditions. Misleading results from antimicrobial susceptibility test leads to the indiscriminate and irrational use of antibiotics and have impacted grossly to the global challenge of antimicrobial resistance. The objectives of this study were to compare the efficacy of different brands of locally and foreign manufactured multi-antibiotic discs on bacteria and assess any significant variation. Two brands each of locally and foreign manufactured multi-antibiotic discs were purchased from retail stores within the FCT. The antibacterial susceptibility of Staphylococcus aureus ATCC 25923, Salmonella typhi ATCC 9150, Klebsiella pneumonia, Pseudomonas aeruginosa, Bacillus subtilis, Escherichia coli ATCC 25922 and Streptococcus pyogenes were carried out using agar diffusion method. There were differences between the diameter zones of inhibition produced by the local brands and the foreign brands of antibiotic discs. Amoxicillin/clavulanic acid (30 µg) disc produced the highest variation within the four brands with zones of inhibition range 12.0 – 20.0 mm against the test organisms. There is need for regulatory bodies like NAFDAC and SON to routinely validate and assess the qualities of these products in the market.

Open Access Original Research Article

Neutrophil Gelatinase-Associated Lipocalin (NGAL): An Early Dual Biomarker in Diagnosis of Ascitic Fluid Infection and Acute Kidney Injury in Liver Cirrhosis in a Tertiary Centre, Egypt

Dalia Kamal Nassar, Mohammed Fouad Elkenawy, Mohammed Mahmoud El-Naggar, El-Sayed Abdul-Maksoud Khalil, Ghada Ibrahim Barakat

Journal of Advances in Microbiology, Page 95-107
DOI: 10.9734/jamb/2020/v20i1230313

Background: This study aimed to evaluate the ascitic Neutrophil gelatinase-associated lipocalin (NGAL) as a diagnostic biomarker for bacterial translocation or bactDNA translocation in ascites of cirrhotic patients and to evaluate the urinary NGAL for identifying renal dysfunction in patients with liver cirrhosis.

Methods: This study included 44 patients with ascites.  Study participants were divided into two groups. Group (1) had 22 patients with neutrocytic ascites and/or positive ascitic fluid (AF) culture while group (2) included 22 patients with culture negative non neutrocytic ascites (CNNNA), recruited as controls. AF and urine samples were collected from all studied participants. ELISA kit was used for measurement of NGAL levels in AF and urine. DNA extraction and PCR were done.

Results: Values of NGAL in ascitic fluid were statistically significantly higher in bactDNA positive group. At cutoff 143.9 ng/ml, ascites NGAL had 86.4% sensitivity, 45.5% specificity, 61.3% positive predictive value (PPV) and 76.9% negative predictive value (NPV). When comparing ascites NGAL between bactDNA positive and negative group, NGAL has a sensitivity of 86.2% and a specificity of 46.7%, PPV of 75.8%, NPV of 63.6%. As for urine NGAL, patients with AKI had statistically significant higher levels of NGAL. Urine NGAL achieved sensitivity of 77.3%, specificity of 50%, PPV of 60.7%, NPV of 68.75%.

Conclusion: Early and accurate diagnosis of BT or bactDNA translocation  can be aided by utilizing NGAL especially in ruling out infection in those reported to have negative culture results, besides, it can help in early detection of complication of cirrhosis and infection especially AKI helping in the improving the prognosis of cirrhotic patients. It is an advantage that a single marker can detect both infection and kidney injury.