Identification of the Bacterial Community Responsible for Decontaminating Eleme Petrochemical Industrial Effluent Using 16s RDNA PCR Denaturing Gradient Gel Electrophoresis

Identification of bacteria community responsible for decontaminating Eleme petrochemical industrial effluent using 16S PCR denaturing gradient gel electrophoresis (DGGE) was determined. Gene profiles were determined by extracting DNA from bacterial isolates and amplified by polymerase chain reaction (PCR) using 16S rDNA eubacterial primers with a GC clamp. PCR amplified DNA was separated by Denaturing Gradient Gel Electrophoresis (DGGE) analysis. Comparative evaluation of primers for PCR amplification of DNA revealed that V6V8F and V6V8R primers were most suitable for amplification DNA. Denaturing gradient gel ratio of 20% : 80% was most suitable for differentiation of bacterial profiles. Sequencing and phylogenetic analysis of DGGE products were successful displaying 88% -100% similarity and homology to Roseococcus sp. LW5(FM956480.1). Dendograms and similarity matrix revealed 81.5% -100% from sampling points.http://dx.doi.org/10.4314/njt.v33i4.

Lead Contamination and Microbial Lead Tolerance in Soils at Major Road Junctions in Benin City

Lead pollution and lead tolerance levels of microbes in soil at major road junctions in Benin City were investigated. Results revealed that distance from the road junctions affected the concentrations of lead in soil,as well as the microbial population density and types of microbes present in the soil. The highest concentrations of lead were recorded with soil samples obtained at 0 and 10m distance closer to road junctions, while the lowest concentrations were recorded with soil samples obtained at 30m distance away from road junctions. The highest concentrationsrecorded for lead, copper and iron were 32 x 101 mg kg-1, 8 x 10-1 mg kg-1 6.3 x 10-1 respectively. All these levels decreased rapidly as the distance from the road increased. Bacterial counts increased as the distance from the road junctions increased. While fungal counts decreased as distance from road junctions increased. Lead tolerance range ofbacterial and fungal isolates was between 10 to 1000 mg 1-1. Non-significant, negative correlation was found between lead concentration and microbal counts. The bacteria and fungi most frequently isolated at 0 and 10m distance were Pseudomonas sp., Micrococcus sp., Bacillus sp., Candida utilis, Penicillium sp and the yeast Saccharromyces cerevisiae. @JASE

Effect of x-rays on the electrolyte concentration of bovine aqueous and vitreous humour

The eye interacts constantly with a wide range of physically occurring materials like x-rays, air pollutants and toxins. The purpose of this study was to investigate the effects of X-rays on the electrolyte concentration of bovine aqueous and vitreous humour. Aqueous and vitreous humours were obtained from the eyes of certified healthy cows freshly slaughtered in the government abattoir at Ikpoba Slope, Benin City, Edo State, Nigeria. These cows’ eyes were enucleated within 2 hours after the death of the animals, and the right eyes were separated from the left eyes. The aqueous humour (AH) and vitreous humour (VH) samples were collected using a 12ml syringe and a needle through scleral puncture made on the lateral canthus and the total extractable aqueous or vitreous humour aspirated from each eye separately. The eyes were transferred to the University of Benin Teaching Hospital (UBTH) Radiology Department where they were irradiated with X-rays machine (VARIAN Medical System model 93061 -7t). Before irradiation, the eyes were removed from ice and allowed to thaw for about 3 minutes. Determination of electrolyte concentration were determined using E110111 flame Photometer (Antex Diagnostics, Beijing, China). Results show that radiation had no statistically significant effect on the mean concentrations of cations and anions in both AH and VH in this study (p > {0.05}). It is therefore concluded that radiation had no statistically significant effect on the mean concentrations of potassium ion and chloride ion in both AH and VH.Keywords: X-rays, electrolyte concentration, Bovine humours, radiatio

Level of Organochlorine pesticide residues in selected consumable vegetables commonly sold in Benin City Markets

This research studied the levels and human health risk assessment of pesticide residues in consumable vegetables such as watermelon, cucumber and onions commonly sold in Benin City markets. A total of twenty-five organochlorine pesticide (OCP) residues in these samples were analyzed using with gas chromatography- electron captured detector (ECD).The estimated acceptable daily intake (EADI) of gamma lindane concentration in fruit vegetable (watermelon, onions and cucumber) was determined based on European union (EU) and United States Agency of Toxic Substances and Disease Registry (ATSDR) standards, using two population age groups (child and adult). The results revealed the levels of organochlorine pesticide residues among the fruit vegetables (watermelon, onions and cucumber). Gamma lindane had the highest value of 0.0002mg/kg among the OCP residues detected in fruit vegetable (watermelon). Onions and cucumber were below detection limit (0.00±0.00). The study, thus suggest that OCPs concentration (gamma lindane) in watermelon is unsafe for human. The study therefore calls for continuous monitoring of agricultural farmlands because continuous exposure to pesticide contaminated food products sold in Benin City markets (watermelon) could affect the health of consumers.Keywords: Pesticide residues, watermelon, cucumber, onion

Effects of Dumpsite Leachates on Soil Biological Sentinels in Benin City, Nigeria

In this study, an attempt was made to examine the effects of dumpsite leachate on soil biological sentinels by collecting leachate samples from Ikhueniro and Otofure dumpsites in Benin City Nigeria, and analyzed using standard methods. The parameters include pH, chemical oxygen demand, biochemical oxygen demand, phosphate, sulphate, chloride, nitrate, chromium, cadmium and lead. The mean results showed pH (8.30 ±0.14), BOD (566 mg/l), COD (1713 mg/l), Phosphate (7.73 ± 0.14 mg/l), Sulphate (22.40 ± 0.75 mg/l), Chloride (187.5 ± 1.12 mg/l), Nitrate (1.47 V 0.06 mg/l), Chromium (0.06 ± 0.1 mg/l), Cadmium (0.20 ± 0.1 mg/l), Lead (1.03 ± 0.04) for Ikhueniro and pH (8.0 ± 0.1), BOD (315 mg/l), COD (1095 mg/l), Phosphate (5.85 ± 0.19 mg/l), Sulphate (31.70 ± 0.73 mg/l), Chloride (135.25 ± 1.59 mg/l), Nitrate (0.93 ± 0.09 mg/l), Chromium (0.06 ± 0.1mg/l), Cadmium (0.109 ± 0.1mg/l), Lead (0.015 ± 0.005 mg/l)for Otofure respectively. Different concentrations of leachate ranging between 25% and 100% was used and the growth of Nitrosomonas sp reduced from 6.4×104(cfu/ml) – 2.9×104(cfu/ml), when compared to the control which increased from 6.4×104(cfu/ml) – 1.0×105 (cfu/ml). The percentage survival of Lumbricus terrestris was 2.19%,  1.14%, 3.42%, 6.69%, with varying concentrations of 25%, 50%, 75%, and 100% respectively. The method implored for analysis shows the leachate sample was toxic to both test organisms. Nitrosomonas sp and Lumbricus terrestris may be used as indicator organisms for leachate toxicity in the soil.Keywords: toxic leachate effects, heavy metals leachate, soil sentinels, earthworm assa

Effects of automobile battery wastes on physicochemical properties of soil in Benin City, Edo State

Difference in soil qualities has been noticeable in many soils due to anthropogenic sources, especially of automobile battery wastes. This study examines the effects of automobile battery wastes on the physicochemical properties of the soil. Soil samples for this study were collected in triplicates from three battery chargers’ workshops: Adolor, Edaiken and Uwelu in Benin City, Edo State at 0-15cm depth, in the months of August, September and October. The soil physicochemical parameters analyzed indicate variations of values in the contaminated soil over uncontaminated soil (control). Among the parameters examined, conductivity was significantly (P<0.01) higher in the contaminated soil (59.3- 184mho/cm) than in the uncontaminated soil. Notably, a more acidic pH value of 3.7-4.5 was also recorded beyond standard limits of 6.5~8.5. Meanwhile phosphorus was relatively high (1.95-3.35) and nitrogen (0.08-0.15) was low as against the control value of 2.71 and 0.18 respectively. Heavy metals such as Lead (Pb), Zinc (Zn), Cadmium (Cd), Chromium (Cr) and Copper (Cu) were present in different concentrations in contaminated soil sample which ranges from far above acceptable standard limit between (0.288-0.875, 0.757- 1.342, 0.108-0.279, 0.718-1.062 and 0.272-0.518 mg/kg) compared to their values in the control soil sample having 0.003, 0.125, 0, 0 and 0.063 mg/kg respectively. Battery wastes were found to be significant sources of Cadmium and Chromium, as none of both was detected in the control soil sample. The daily activities of auto-mechanic battery workshops have negative impacts on soil physicochemical properties. Note, the soil in mechanic battery workshops needs urgent cleanup to minimize contamination of ecological materials and public health implication. This work will prove valuable in providing baseline information for further soil quality monitoring studies in study areaKEYWORDS: Physicochemical, Heavy metals, Battery wastes, Contaminated and uncontaminated soil

Antibiotic Resistance and Plasmid Profiles of Bacteria Isolated from Abattoir Effluents around Ikpoba River in Benin City, Nigeria

Abattoirs are known all over the world to pollute the environment either directly or indirectly from their various processes. The aim of this work is to determine the bacterial load, antibiotic resistance and plasmid profile of resistant bacteria isolated from government and private abattoirs around in Ikpoba River in Benin City. Bacteria and coliform count were done using pour plating method. The total viable bacteria counts ranged 4.2x105±1.8 - 1.5x106± 0.7 cfu/ml and 1.3x106± 0.1-3.1 x 106 ± 0.5cfu/ml for government and private abattoir respectively, The coliform count ranged from 2.7x105± 0.1 - 3.8x105±1.4 cfu/ml and 5.5x105±0.3 - 9:2x105±0.4 cfu/ml for government and private abattoir respectively. Escherichia coli, Streptococcus faecalis, Pseudomonas aeriginosa, Enterobacter aerogenes, Micrococcus luteus, Bacillus subtills and Staphylococcus aureuswere isolated and identified by cultural, morphological and biochemical characteristics. Susceptibility of the microbes was determined. The isolates were resistant to most of the commonly used antibiotics. Plasmid profile of isolates was also determined. The profile study shows that all resistant bacterial isolates harbored plasmid mediated resistance to antibiotics which was confirmed by plasmid curing. Therefore this research showed contamination of abattoirs effluents with antibiotic resistant bacterial isolates. This specially calls for treatment of the wastewater before discharging into the river.Keywords: Effluent, abattoir, antbiotic resistance, plasmid profile

A study of the microbiology and polycyclic aromatic hydrocarbons (PAHs) compositional profile and sources in drill cuttings from Ologbo oilfield wells at Edo State, Nigeria

A study was carried out on the drill cuttings from three different oil and gas wells located at Ologbo Community at Edo State with respect to their  microbiology and polycyclic aromatic hydrocarbons (PAHs) compositional profile and sources. Isolation and enumeration of heterotrophic bacteria and fungi was carried out using pour plate techniques. pH and electrical  conductivity were monitored using single electrode meters. Polycyclic Aromatic Hydrocarbon was determined using gas chromatography, oil and  grease concentration was analyzed using spectrophotometric method. Results of total heterotrophic bacterial counts ranged between 5.4 x 105 cfu/g at well 2 to 7.23 x 105 cfu/g while the heterotrophic fungal counts  ranged from 3.7 x 104 cfu/g to 3.0 x 105 cfu/g. Total heterotrophic  anaerobic bacterial counts also ranged from 0.8 x 102 cfu/g to 1.7 x 102 cfu/g. The most predominant bacterial isolates were Clostridium spp.  (16.6%) and Mycobacterium spp. (14.5%). Species of Aspergillus (16.6) and Penicillium (14.2) also had the highest frequency of occurrence among the fungi isolates. The pH ranged from 5.42 to 5.78. The highest electrical  conductivity value was 383 ìS/cm. The range for oil and grease was from 8352 to 9654.61 mg/kg. Of the heavy metals iron had the highest concentration (126 ppm) while least concentration was observed in zinc (61 ppm). The 3-ring PAHs had the highest percentage composition for  samples from the three (3) different wells (53, 73 and 89 for well 1, 2 and 3 respectively). The source identification by isomer ratios of PAHs revealed that drill cuttings from Wells 1 - 2 were of pyrogenic origins, while cuttings from well 3 indicated both petrogenic and pyrogenic origin. It was quite clear that drill cuttings emanating from Ologbo oilfield wells were unsafe for disposal and therefore will require a strict adherence of the procedures and instructions described for oil drilling exploration and procedure (E and P) waste management in Nigeria.Keywords: : drill-cuttings, muds, microbial qualities, PAHs, heavy metals

Eco-toxicological effects of pesticide residues on soil biological sentinels

This research studied the eco-toxicological effects of pesticide residues on soil biological sentinels. Nitrobacter and Nitrosomonas sp. was isolated from Soil samples gotten from dumpsite in Benin City and cultured using Winogradsky medium. The bacterial isolate was characterized and identified based on its cultural, morphological and biochemical characteristics. After 4 to 5 days of growth, Nitrobacter and Nitrosomonas Counts obtained from Winogradsky medium ranged from 1.87±0.95 to 2.43 ± 1.1 x 104cfu/g. The pesticides were observed to have negative effect on the growth of Nitrobacter and Nitrosomas sp. in broth culture media. The effective and lethal concentration (EC50) and (LC50) for each of the pesticides were observed to decrease with increase in the time of exposure and the effects of the two pesticides on both nitrite oxidations by Nitrobacter sp. and ammonia oxidation by Nitrosomonas sp. were similar. The results also showed that earthworms had weight loss and death at different concentration of the pesticide and time of exposure, with the lethal concentration (LC50) of aldrin being 2.84mg/ml while that of lindane was 3.54mg/ml after 48hr of exposure period. More so, the result obtained from this study suggest that autotrophic transformation by nitrifying bacteria and earthworm which enhances soil fertility (hence significant in crop production) may be hindered in an ecosystem polluted with these pesticide formulations, as nitrification processes will be reduced. Thus, more efforts should be geared at reducing the indiscriminate and illegal use of pesticides (banned or approved).Keywords: Pesticide residues, nitrobacter sp, nitrosomonas sp, Winogradsky mediu

Comparison of the Etest and the routine multi-disc agar diffusion susceptibility of Staphylococcus species

Aims: The present study, tend to evaluate the validity and accuracy of Etest as a method for performing in-vitro antimicrobial susceptibility testing of Staphylococcus with comparison to the routine multi disc agar diffusion. This is because the Etest susceptibility method is not yet known as a rapid, simple reliable technique in developing countries as it combine the functions of both dilution and diffusion technique. Materials and methods: Ninety-seven Staphylococcus aureus and eightythree Staphylococcus epidermidis isolates were obtained from wound samples and identified according to standard morphological and biochemical methods. The antibiotics susceptibility patterns were determined both by agar disc diffusion and Etest methods in accordance to NCCLS (1997) criteria and manufacturer (AB Biodisk Sweden) respectively. Results: On the Etest strips, Staph aureus was 83.5% sensitive to ciprofloxacin, 52.6% to gentamicin, 48.5% to ampicillin and 8.2% to chloramphenicol while on the multi-disc agar diffusion plates 80.4% of Staph aureus were sensitive to ciprofloxacin, 49.5% to gentamicin, 39.2% to ampicillin and 12.4% to chloramphenicol.. On the Etest strips, 80.7% of Staph epidermidis were sensitive to ciprofloxacin, 34.9% to gentamicin, 25.3% to ampicillin and 15.7% to chloramphenicol while on the multi- disc agar diffusion plates 89.2% of Staph epidermidis were sensitive to ciprofloxacin, 34.9% to gentamicin, 25.3% to ampicillin and 32.5% to chloramphenicol. Conclusion: The sensitivity patterns between the two methods were essentially similar, however, the Etest method clearly demonstrated intermediate sensitivities which to an extent were absent in routine multi-disc agar diffusion method. Most of the isolates Etest MICs clustered around the sensitive and resistance break points. Etest also demonstrated the MIC and diffusion results on the same strips. Keywords: antibiotic resistance, antimicrobial, gram-positive, chemotherapy.Sudan Journal of Medical Sciences Vol. 3 (2) 2008: pp.121-12