Open Access Short communication

Serological Evidence of Hepatitis E Virus in Dromedary Camels in the Sahelian Zone of West Africa

Jean Bienvenue Ouoba, Anne Ouedraogo, Kuan Abdoulaye Traore, Bruno L. Ouoba, Hortense Rouamba, Lamouni Habibata Zerbo, Sidi Moctar, Amadou Traore, Pierre Roques, Nicolas Barro

Journal of Advances in Microbiology, Page 1-7
DOI: 10.9734/jamb/2019/v15i430110

Aim: This study was undertaken to determine the sero-epidemiological information and associated risk factors, of Hepatitis E virus (HEV) among dromedaries in Sub-sahelian region.

Study Design: Cross sectional epidemiological survey.

Place and Duration: The study was carried out in three countries of West Africa (Burkina Faso, Mali and Niger), over a two month period from February to March 2015.

Methodology: A total of 133 serum samples collected from dromedaries (Camelus dromedarius) were examined for the detection of anti-DcHEV total antibody by a mammals targeted ELISA kit (ID vet, France), using a multispecies conjugate.

Results: Eleven of the 133 (8.33%; 95%CI [3.6 – 13.0]) dromedaries were positive for anti-DcHEV antibodies. Positive cases had a random geographic distribution (p˃0.05) and all seropositive dromedaries were in close contact with other domestic animals.

Conclusion: This study highlight the circulation of HEV in West African mammals and specifically in dromedaries. This is the first study reporting HEV circulation in dromedaries in West Africa. Further studies is needed to identify the HEV genotype involved in the dromedary camel infection, and evaluation of potential transmission to dromedary’s care keepers.

Open Access Original Research Article

Response of Soil Microorganisms to Oilfield Wastewater

Aleruchi Owhonka, Obire, Omokaro

Journal of Advances in Microbiology, Page 1-8
DOI: 10.9734/jamb/2019/v15i430107

Environmental pollution resulting from oil exploitation and exploration has impacted negatively on the biodiversity of the affected areas. Therefore, this study investigated the response of soil microorganisms to oilfield wastewater. The oilfield wastewater and soil samples were collected from an onshore oil producing platform fortnightly for a period of three months and microbiological analyses were performed using standard methods. Soil around pond average counts for THB and HUB (Log10 CFU/g) were 7.32 to 7.35 and 4.16 to 4.22 respectively. Soil 80 m away from pond average range for THB and HUB were 7.38 to 7.40 and 3.32 to 3.34 respectively. For TF and HUF, Soil around the pond mean recorded 4.65 to 4.85 and 4.12 to 4.16 (Log10 CFU/g) respectively. Mean monthly counts for soil 80m away TF and HUF (Log10 CFU/g) were 5.03 to 5.05 and 3.26 to 3.34 respectively. Soil around the pond recorded lower total heterotrophic bacteria count and total fungi count but higher hydrocarbon utilizing bacteria and hydrocarbon utilizing fungi than soil 80 m away.

There was significant difference (P<0.05) between the THB and HUB in the various samples. For the fungi count there was no significant difference (P>0.05) between TF and HUF in all the samples except in sample obtained from soil 80 m away from pond.

Bacteria species isolated from the study include: Bacillus, Aeromonas, Micrococcus, Staphylococcus, Chryseomonas, Proteus, Pseudomonas, Klebsiella. Apart from Aeromonas and Chryseomonas the rest of the isolate were identified also as hydrocarbon utilizing bacteria. While fungi species isolated includes: Aspergillus fumigates, Aspergillus niger, Aspergillus flavus, Saccharomyces cerevisiae, Geotricum, Trichoderma, Fusarium and Penicillium. Hydrocarbon utilizing fungi that occurred includes: Aspergillus niger, Aspergillus flavus, Fusarium, Penicillium and Saccharomyces cerevisiae. The response of these microorganisms in the oil polluted environment suggests that the isolated bacteria and fungi could utilize the oil as energy and carbon source and could be effective in the cleanup of the polluted sites.

Open Access Original Research Article

Influence of Pesticides on Azospirillum sp. Population and Its Nitrogen Fixation in Groundnut (Arachis hypogaea L.) Soils

A. Madhavi, B. Anuradha, V. Rangaswamy

Journal of Advances in Microbiology, Page 1-12
DOI: 10.9734/jamb/2019/v15i430108

Aim: To study the impact of selected pesticides on Azospirillum sp. population and its nitrification in groundnut (Arachis hypogaea L.) soils.  

Study Design: Black clay and red sandy loam soils with known pesticide history were collected from groundnut (Arachis hypogaea L.) cultivated fields and were investigated to elucidate the impact of pesticides on Azospirillum sp. population and its nitrification in both the soils.

Place and Duration of Study: The soil samples were collected from groundnut cultivated fields of Anantapur District, Andhra Pradesh (A.P) and the study was carried out for 3 months.

Methodology: Ten gram portions of each soil sample were placed in (25 × 150 mm) test tubes and treated with different concentrations of pesticides, (10, 25, 50, 75 and 100 µg g-1 soil) which were equivalent - 1.0, 2.5, 5.0, 7.5 and 10 kg ha-1. Soil samples without pesticides served as controls. The soils with and without pesticides were incubated at room temperature (28 ± 4°C) in the laboratory and moisture content was maintained at 60% water holding capacity (WHC) throughout the experimental period. After 7 and 14 days of incubation, triplicate soil samples were used to estimate the population size of Azospirillum sp. using the MPN method. Five ml aliquots of semi – solid malate medium were added to five MPN tubes and inoculated with 0.5 ml of a soil suspension from 10-1 to 10-5 soil dilutions, and incubated at 37°C.

Results: The population of Azospirillum sp. in both soils increased when pesticides were applied @ 2.5 - 5.0 kg ha-1 and incongruity, when the pesticides concentration increased from 7.5 - 10.0 kg ha-1, the Azospirillum sp. population gradually decreased in both soils.

Conclusion: The present study aimed at determining the influence of selected pesticides such as oxydemeton methyl, emamectin benzoate, dithane Z-78 and benomyl on the population of Azospirillum sp. and nitrogen fixation in black clay soil and red sandy loam soils in groundnut cultivated fields of Anantapur District, Andhra Pradesh, India. Insecticides and fungicides applied up to 5.0 kg ha-1, enhanced the population of Azospirillum sp. and its nitrogen fixation also increased significantly after 7 and 14 days of incubation in both soils. However, the population of Azospirillum sp., decreased with increasing period of soil incubation in both treated and untreated soils.

Open Access Original Research Article

Effect of Soil Microbes on Nitrate, Phosphate and Total Hydrocarbon Content of Various Concentrations of Oilfield Wastewater

Aleruchi Owhonka, Obire, Omokaro

Journal of Advances in Microbiology, Page 1-5
DOI: 10.9734/jamb/2019/v15i430109

The effects of soil microbes on nitrate, phosphate and total hydrocarbon content of various concentrations of oilfield wastewater were investigated for a period of 28 days using standard methods. Periodic sampling of the treatment options from each flask were carried out after 24 hrs and subsequently at 7 days interval for nitrate, phosphate and total hydrocarbon content analysis. The nitrate, phosphate and total hydrocarbon content were higher in all the treatment options than in the control (0%). The concentration of nitrate and phosphate in the soil treatment options reduced significantly at day 28. Total hydrocarbon content of the 0% (control) on 24 hrs was 48 mg/kg and 26 mg/kg on 28th day, while 10, 25, 50 and 75 (%) were 160 and 98, 162 and 94, 163 and 98, 163 and 96 mg/kg respectively. There was significant reduction between the incubation period (24 hr and 28 days) in the various treatment option including the control.  The results revealed that nutrients (nitrate and phosphate) were been utilized by the soil microbes and further enhanced microbial utilization of hydrocarbons. This suggests that oilfield wastewater could serve as nutrient enhancement medium for indigenous soil microbes in bioremediation process.

Open Access Original Research Article

Occurrence, Distribution and Antibiotic Sensitivity Pattern of Bacteria Isolated from Some Selected Fishes Sold in Bodija Market, Ibadan, Nigeria

O. B. Balogun, O. Ogunsanmi, I. O. Olutimehin

Journal of Advances in Microbiology, Page 1-7
DOI: 10.9734/jamb/2019/v15i430111

Fish constitutes the cheapest source of animal protein in the world. The nutritional qualities and the shelf ability of fish can be affected due to microbial contamination after harvesting. Hence, this study is designed to investigate the microbiological analysis of fish and the antibiotic sensitivity pattern of the isolated bacteria from some selected fish sold in Bodija Market in Ibadan, Nigeria. Three different fish samples: Catfish (Clarias gariepinus), Sabalo fish (Prochilodus lineatus) and Tadpole fish (Raniceps raninus) were bought from Bodija market in an ice packed bag and then transported to Microbiology laboratory for further analyses. Microbial analysis were carried out using serial dilution and pour plate methods. The antibiotic sensitivity pattern on the bacteria isolates were carried out using commercial antibiotics. E. coli, Pseudomonas aureginosa, Staphylococcus aureus, Serratia spp, Klebsiella spp, Salmonella spp, Shigella spp were isolated. Gram negative bacteria were more susceptible to most of the antibiotics used than gram positive bacteria. E. coli showed the highest susceptibility to all the antibiotics with varied zone of inhibitions. Salmonella spp show the highest susceptibility to septrin with the lowest zone of inhibition to pefloxacin. Shigella spp had the lowest zone of inhibition to gentamycin, rocephin, septrin and erythromycin when compared to other bacterial isolates. Serratia spp exhibited highest zone of inhibition to gentamycin. Fish contamination can be averted by employing good environmental conditions and preservation methods to avoid spoilage. The antibiotics sensitivity showed that all the bacteria isolated were more susceptible to antibiotics, thereby developing a resistant strain.