Total Aerobic Heterotrophic Bacteria Research Articles

Investigation of the Levels of Bio-Indicator Bacteria in the Kınalıada Coastal Area, Istanbul, Turkey

Coastal areas have an important place in island ecosystems. These areas, which may be fragile depending on the impact of human activities exposed and other environmental factors and in addition to domestic, agricultural and industrial activities, it hosts intensive touristic use in spring and summer. In this study, the closest contact with the shores of a mainland like Istanbul, among the Prince Islands in the Marmara Sea which is under the influence of the vast majority of the pollution load Kınalıada has been selected as a research area. Total heterotrophic aerobic bacteria (HAB) levels were analyzed using spreading plate method. The levels of fecal coliform (FC), total coliform (TC) and intestinal streptococci (IS) examined using Membrane Filtration Technique in the surface water samples. Variable environmental parameters (dissolved oxygen, pH, salinity, temperature) were recorded periodically using the Multiparameter (YSI 556 MPS) with seawater samples. Nutrient salts (nitrite nitrogen, nitrate nitrogen, ammonium nitrogen, phosphate phosphor), trophic level indicator Chlorophyll-a were analyzed using spectrophotometric methods. While the highest TC, FC and IS level detected as 96x103 CFU/100 ml, 49x103 CFU/100 ml, 82x103 CFU/100 ml, respectively. The highest HAB level was determined as 92x1011CFU /ml .Variable environmental parameters recorded for seawater temperature between 25.7-6.89˚C, pH 11.55 -3.60, dissolved oxygen 19.98 -1.66 mg /l and salinity ‰ 29.11-21.18 during the study period. Nutrient salts; nitrite nitrogen detected to be 0.21-0.01 mg/l; nitrate nitrogen detected to be 9.90-0.13 mg/l; ammonium nitrogen detected to be 4.80-0.02 mg/l; phosphate phosphor detected to be 22.45-0.01 mg/l. The levels of FC, TC and IS determined in Kınalıada coastal area fluctuate depending on the seasons, but these levels are determined above the legal limits. The presence of bio-indicator bacteria detected above the border throughout the sampling shows that it poses a serious risk for ecosystem health and public health.

Molecular Characterization and Antibiogram of Selected Pathogens Isolated from Streams and Wells Water Sources in Three Local Government Areas of Rivers State, Nigeria

Aims: Reliance on unhealthy water sources such as hand dug wells and streams have led to the occurrence of waterborne diseases such as amoebic dysentery, gastroenteritis, typhoid fever and cholera among several communities in Rivers State. This study tends to identify selected multidrug resistant pathogens isolated from streams and wells water sources in three Local Government Areas of Rivers State using molecular techniques.
 Methodology: A total of 48 well and stream water samples were collected aseptically from 24 sampling sites in Ikwerre, Emohua and Etche Local Government Areas of Rivers State. Samples were analysed using membrane filtration technique for total heterotrophic bacterial count and total coliform count. The well and stream water samples were also cultured for E. coli, Salmonella and Vibrio sp. Antibiotic sensitivity test of the isolates was carried out using the disk diffusion method and multidrug resistant isolates were identified using PCR-based techniques (16S rRNA).
 Results: The results of this study showed that total aerobic heterotrophic bacteria count occurred more in Emohua LGA for both well and stream water sources with bacterial count of 1.71 x104 cfu/ml for well water samples and 2.35 x 104 cfu/ml for stream water samples. The mean fungal count of the stream water samples was highest in Emohua LGA with 2.55 x 104 cfu/ml followed by Ikwerre LGA which had 4.20 x 103 cfu/ml and Etche LGA with the least count of 1.80 x 102 cfu/ml. All the isolated bacteria species were found to be resistant to more than 50% of the antibiotics used with highest Multi Antibiotic Resistant Index of 0.625. multidrug resistant bacterial isolates identified include Vibrio sp strain 201707CJKOP-Y162 (MG593726), Bacillus sbtilis clone N55 (JQ622582), Chryseobacterium sp strain CB2915-325-DE_0621 (MH512534), Enterobacter sp strain AB55 (MF407145), Klebsiella pneumonia strain M792-16(MH680830), Shigella sonnei strain AR_0030(CP032523), Escherichia coli strain WECHEC025943(CP027205) and Salmonella bongori strain KC153129.116 (MG663494).
 Conclusion: Access to good quality or potable drinking water and efficient sanitary practices are fundamental to human health and economic development. The occurrence of multidrug resistant pathogenic bacterial isolates in natural water sources requires serious routine evaluation in order to forestall the outbreak of waterborne disease epidemics.

Bacteriological examination of the water and sediments in Palhi and Salog rivers in Western Leyte, Philippines

Rivers around the world are threatened by destruction caused by anthropogenic activities despite the important services they provide for humanity. This study was conducted to determine the water classification and recommended beneficial uses of Palhi and Salog Rivers based on the most probable numbers of total coliforms, and also to evaluate the abundance of heterotrophic bacteria present in the water and sediments of the rivers as potential indicators of environmental disturbance. A Multiple-tube fermentation test was conducted to determine the most probable number of total coliforms in the river waters. Heterotrophic plate count of total aerobic heterotrophic bacteria was determined by counting the colony-forming units that grew on nutrient agar. Geometric most probable number means of total coliforms revealed that only the upstream of Palhi and Salog Rivers could be used for contact recreational activities. The midstream and downstream of both rivers are recommended for non-contact recreational activities only, due to elevated total coliforms. The heterotrophic plate count of total aerobic heterotrophic bacteria of water and sediment samples for the three stations in Palhi River were not significantly different while in Salog River higher numbers of total aerobic heterotrophic bacteria occurred in the downstream compared to the upstream. However, no significant differences on the heterotrophic plate count of total aerobic heterotrophic bacteria levels were found between the water and sediments for the two rivers. The results of this study imply that monitoring and proper management of the rivers should be done by all sectors of the community for the protection of these invaluable resources.

Intestinal Microbial Ecology and Fillet Metal Chemistry of Wild Grey Mullets Reflect the Variability of the Aquatic Environment in a Western Mediterranean Coastal Lagoon (Santa Giusta, Sardinia, Italy)

Fish populations play an active role in the maintenance of aquatic ecosystems biodiversity. Their intestinal microbiota and fillet chemistry depend on abiotic and biotic factors of the water environments that they inhabit. The present study investigated the grey mullets’ gut microbiota from a transitional aquatic ecosystem (Santa Giusta Lagoon, Sardinia, Italy) by a multidisciplinary approach which refers the results of (1) gut cultivable microbiota analyses (MA), (2) the trace metal assessment of fish muscle (TM), (3) the physico-chemical water monitoring (PC). MA detected the greatest number of total aerobic heterotrophic bacteria, Enterobacteriaceae and coliforms in Autumn (mean values 1.3 × 105, 2.4 × 104, 1.1 × 104 cfu g−1, respectively) when the accumulated rain and mean values of nutrients (reactive phosphorous and silica) were the highest. Marine bacteria were more numerous in Summer (mean value 7.4 × 105 cfu g−1) when the highest mean values of water temperature and salinity were registered. The gut bacteria were identified as Pseudomonas spp. (64%), Aeromonas spp. (17%), Ochrobactrum pseudogrignonense (10%), Providencia spp. (5%), Enterobacter ludwigii (2%) and Kocuria tytonicola (2%). TM showed that Ca, Na, B and Ni increased their concentrations in Winter while maxima of P, Zn, Cu and Fe were found in muscles of fish sampled in Summer. This study highlighted that the fish intestinal microbiota and metal composition of the fillet reflected the seasonal aquatic environmental variability.

The Bacteriological Risk Transported to Seas by Rivers; the Example of Çırpıcı River, the Sea of Marmara

The identification of bacteriologically characters of coastal areas is important due to the fact that bacteriological pollution, transported to seas via rivers is a potential threat for ecosystem, animal and human health. In this study, bacteriological load of Çırpıcı River transporting to the Sea of Marmara from Zeytinburnu location in Istanbul and its relationship with primary hydrographic parameters investigated. The levels of fecal coliform (FC), total coliform (TC), fecal streptococci (FS) and total heterotrophic aerobic bacteria (HPC) tested using Membrane Filtration Technique in the surface water samples. Seawater temperature, pH, salinity, dissolved oxygen were recorded in-situ using multiparameter (YSI556 MPS). While the highest TC detected to be 13x107 CFU/100 ml, the highest FC was 14x106 CFU/100 ml. The lowest FC recorded as 25x10 CFU/100 ml. While the highest FS level was determined to be 73x105 CFU/100 ml, the highest HPC was 14x106 CFU / ml. Variable environmental parameters recorded for seawater temperature between 10.3-29.5˚C; pH 6.0-8.38; dissolved oxygen 0.34- 10.71 mg /l and salinity 16.50-26.57 psu during the study period. Significant correlation between the temperature and FC, FS and THAB detected. The levels of bacteria detected at the spot where the Çırpıcı River poured into the Sea of Marmara were found higher than the station at the 800 m open of the Sea of Marmara. It was determined that the Çırpıcı River carried 103 CFU bacterial loads at 100 ml for TC to the Sea of Marmara. The FC and FS counts carried to the Marmara Sea from Çırpıcı River recorded to be 102/100 ml and 103/100 ml, respectively. The fact that FC and TC levels were above the limit values during the study indicate the stability of pollution sources in the region and that the Çırpıcı Stream carries a bacteriological risk in terms of human, animal, and environmental health.

Investigation of the Incidence of Legionella and Free-Living Amoebae in Swimming Pool Waters and Biofilm Specimens in Istanbul by Different Methods

Legionella bacteria living in free form or in biofilm and free-living amoebae (FLA) can infect humans through swimming pools and can cause various diseases. FLA may also threaten the health of swimmers because they are capable of being hosts for Legionella and some other bacteria. The aim of this study was to investigate the presence of total aerobic heterotrophic bacteria (TAHB), FLA and Legionella bacteria in swimming pool waters and biofilm samples in Istanbul by using culture and FISH methods. Water plate count agar (wPCA), buffered charcoal yeast extract (BCYE) agar supplemented with glycinevancomycin-polymyxin-cycloheximide (GVPC) and Escherichia coli cultivated non-nutrient agar (NNA) were used for the culture of TAHB, Legionella and FLA. For the FISH method analysis , Leg 705 and Leg PNE1 probes labeled with fluorescent dye for Legionella and ACANTHA probe for Acanthamoeba genus FLA were used. Legionella pneumophila serogroup 1 ATCC 33152, L.pneumophila serogroup 3 ATCC 33155 and Acanthamoeba castellani ATCC 50373 were used as positive controls. TAHB were grown in 92% and 84% of water and biofilm samples. Although Legionella bacteria could not be grown in any of the water samples, it was detected in 6 (24%) water samples by FISH method. Although these bacteria could be grown in 1 (4%) of biofilm samples, 7 (28%) were detected by FISH method. FLA were found to be 16% by culture in water samples and 28% by FISH analysis. These amoebae were detected 8% and 20% in biofilm samples by culture and FISH method, respectively. It was determined that one of the isolates of FLA had thermotolerant activity (potentially pathogenic). L.pneumophila serogroup 1 was detected in one water sample and in four biofilm samples. According to the culture method, TAHB and FLA were found to be more common in water samples than in biofilm samples and Legionella bacteria were more common in biofilm samples than in water samples (p≤ 0.05). In the detection of Legionella bacteria, the superiority of FISH method compared to culture method was found to be statistically significant (p≤ 0.05). In this study, it was found that the number of TAHB in the controlled swimming pools was within the limits determined by the Ministry of Health (≤ 200 cfu/ml). It will be appropriate to examine both water and biofilm samples for the investigation of TAHB, FLA and Legionella. It may be appropriate to use both culture and FISH methods to detect the presence of FLA in water and biofilm samples. This study is the first study to investigate the presence of Legionella and FLA in swimming pools in Istanbul, and further studies are needed to examine more pool water and biofilm samples. With the data obtained, the health principles and controls of swimming pools will be re-considered and will be contributed to public health.

Depth-Dependent Response of Fecal Indicator Bacteria in Sediments to Changes in Water Column Nutrient Levels.

Concentrations of in bottom sediments can influence the assessment of microbial stream water quality. Runoff events bring nutrients to streams that can support the growth of in sediments. The objective of this work was to evaluate depth-dependent changes in populations after nutrients are introduced to the water column. Bovine feces were collected fresh and mixed into sediment. Studies were performed in a microcosm system with continuous flow of synthetic stream water over inoculated sediment. Dilutions of autoclaved bovine manure were added to water on Day 16 at two concentrations, and KBr tracer was introduced into the water column to evaluate ion diffusion. Concentrations of , total coliforms, and total aerobic heterotrophic bacteria, along with orthophosphate-P and ammonium N, were monitored in water and sediment for 32 d. Sediment samples were analyzed in 0- to 1-cm and 1- to 3-cm sectioned depths. Concentrations of and total coliforms in top sediments were approximately one order of magnitude greater than in bottom sediments throughout the experiment. Introduction of nutrients to the water column triggered an increase of nutrient levels in both top and bottom sediments and increased concentrations of bacteria in the water. However, the added nutrients had a limited effect on in sediment where bacterial inactivation continued. Vertical gradients of concentrations in sediments persisted during the inactivation periods both before and after nutrient addition to the water column.

Influence of environmental disturbances on the bacteriological quality of Pagbanganan river in Baybay City, Leyte, Philippines

Microorganisms like bacteria are frequently used as indicators of water quality in freshwater ecosystems. Thus, this study was conducted to evaluate the total coliforms (TC) and total aerobic heterotrophic bacteria (TAHB) present in the upstream (Kantagnos), midstream (lgang), and downstream (Kan-ipa) of Pagbanganan River. The most probable number (MPN/100 mL) of TC was determined through multiple tube fermentation test while counts of TAHB present in both water and sediments were enumerated by serial dilution and plating methods. MPN of TC revealed that the river water should not be used as a source of public water supply and as a venue for contact recreational activities like bathing and swimming. Furthermore, TAHB in the sediments of the river did not differ significantly across sites although their values showed a decreasing trend. Conversely, TAHB in the water column of the river significantly increased from upstream to downstream. These results are most probably influenced by the quarrying activities present in the area. In the upstream where there is no quarrying activity, TAHB was higher in sediment than in the water, while in the downstream where quarrying activities are present, it is otherwise. Because of these significant differences, it is believed that the ratios of TAHB present in the water column and sediments are potential indicators of sediment disturbance in the aquatic environment. The results of this study imply that proper management of Pagbanganan River by all sectors of the community is needed to keep it sustainable for safe use.

Inhibitory action of thymol on fecal microbial activity in Tamandua tetradactyla and its effect on glucocorticoid metabolite measurement

Faecal glucocorticoid measurement is a potentially important tool for improving wildlife conservation, but its use is still limited by methodological issues including the need to avoid modifications of steroids by faecal microorganisms during storage. The freezing of faeces is recommended as a means of avoiding such alterations, but this is costly under non-controlled environmental conditions. The present study was designed to determine whether the application of thymol reduced the proliferation of microorganisms in the faeces of Tamandua tetradactyla and whether it influenced faecal glucocorticoid metabolite (FGM) measurements. Tamandua tetradactyla faeces were individually collected after defaecation, divided into fractions (5.5 g each) and kept in sealed glass Petri dishes at 22 ± 2 °C. A thymol solution (550 µL; 5 mg g−1 feces; 80% ethanol) or an 80% ethanol solution (550 µL, control) was added before storage of faeces. Negative controls for FGM consisted of samples without thymol or ethanol solutions. All samples were evaluated at 0, 24, 48 and 72 h post-defaecation. Thymol was first incubated with a glucocorticoid standard in a faeces-free tube or in a faecal sample in order to determine whether it interfered with FGM measurements. Data showed that thymol did not affect FGM measurements. Post-defaecation time caused a significant reduction in FGM measurements in the negative control, an increment at 48 h in the control, and no change in FGM measurements in thymol treatment. FGM measurements were significantly different between groups (negative control > control – treatment). Thymol caused a significant reduction of up to three orders of magnitude in total coliforms, total aerobic and anaerobic heterotrophic mesophilic bacteria, mold and yeast per gram of faeces at 24, 48 and 72 h. The reduction in microbial activity presumably contributed to the stability of FGM over time. Spore-forming bacteria (SFB) in faeces were not reduced by thymol. We propose thymol as an alternative to freezing since it stabilizes FGMs for at least 3 days after collection in the faeces of Tamandua tetradactyla.

Isolation and characterization of microorganisms of Ejamah-Ebubu oil spill site

The study was designed to evaluate the bacterial diversity of crude oil contaminated site. Sediments samples collected at different georeferenced sampling point; Nwata A, Nwata B, Nwata 3, Ochani and Eyeyaro in Ejamah-Ebubu were analyzed for microbiological and biochemical qualities using the basic biological method. Our results show that the total aerobic heterotrophic bacteria (HUB) of the five sampling points range from 1.0x105 - 1.7x106cfu/g. Total aerobic hydrocarbon utilizing bacteria (HUB) range from 1.0x10 4- 7.2x105cfu/g while sulphate reducing bacteria (SRB) ranged between 2.2x104-1.6x105 cell/ml. Careful phenotypic and biochemical test revealed twenty oil degrader belonging to five genera; Bacilus, Citrobacter, Micrococcus, Enterobacter and Pseudomonas . The frequency of occurrence of the microbial isolate revealed Bacillus (40%), Citrobacter, (25%) Pseudomonas (15%), Enterobacter and Micrococcus (10%) . This study indicates that the contaminated sediment samples contain a diverse population of oil degrading bacteria and the use of sediment-associated microorganism has the potential for bioremediation of crude oil contaminated sites. Keywords : Georeferenced, crude oil, diversity, Bacillus, sulphate reducing bacteria

Modulation of growth performance, immunity, and disease resistance in narrow-clawed crayfish, Astacus leptodactylus leptodactylus (Eschscholtz, 1823) upon synbiotic feeding

In the present study, a 126-day experiment was carried out under controlled conditions to compare the effects of prebiotic (galactooligosaccharide), probiotics (Enterococcus faecalis and Pediococcus acidilactici), and synbiotics (galactooligosaccharide+Enterococcus faecalis and galactooligosaccharide+Pediococcus acidilactici) on the growth performance, indices of nutritional efficiency, in vivo apparent digestibility coefficients of nutrients, digestive enzymes, hemolymph indices, and biological responses of juvenile crayfish Astacus leptodactylus leptodactylus (6.18±0.31g) against 48-h Aeromonas hydrophila exposure challenge. The maximum specific growth rate (2.32%day−1), voluntary feed intake (2.68%bodyweightday−1), and survival rate (93.67%) as well as the minimum feed conversion ratio (2.07) were observed in the juvenile crayfish fed with the galactooligosaccharide+Enterococcus faecalis diet. The highest means of in vivo apparent digestibility coefficients of organic matter (85.33%), crude protein (91.67%), crude fat (82.33%), and gross energy (83.67%) were measured in the crayfish fed with the galactooligosaccharide+Enterococcus faecalis diet (p<0.05). Moreover, the highest ratios of presumptive autochthonous lactic acid bacteria to total viable aerobic heterotrophic bacteria were observed in the crayfish fed with the synbiotic diets (p<0.05). It was found that feeding crayfish with the galactooligosaccharide+Enterococcus faecalis diet indicated the highest activities of phenoloxidase, superoxide dismutase, lysozyme, and nitric oxide synthase (p<0.05). The mean survival rate of Aeromonas hydrophila injected crayfish fed with the galactooligosaccharide+Enterococcus faecalis diet (77.67%) was higher than that of the crayfish fed with the control (8.33%) and other diets (58.33–72.33%) (p<0.05). Finally, considering all the tested levels, 7.53logCFUE.faecalisg−1+10gkg−1 galactooligosaccharide used in the diet was observed to be the optimum diet.

The effects of storage on the bacteriological quality of sachet water produced, sold and consumed within Owerri Metropolis, Imo State, Nigeria

The sale and consumption of sachet water is common in Owerri metropolis because the consumers believed it was safer than tap or borehole water.The aim of this study was to assess the effects of storage on the bacteriological quality of sachet water produced, sold and consumed within Owerri metropolis, Imo State, Nigeria. Fifteen sachet water brands were investigated for a period of four months. They were collected within 24 hours of production and stored at ambient temperature for four months. Samples were taken on monthly basis for enumeration of total aerobic heterotrophic bacteria and indicator organisms using APHA and WHO analytical methods. Bacteriological analysis showed that Clets brand had the highest Total heterotrophic bacterial count of 5.7X101cfu/ml, followed by Elevated and Crystal while Ricano had the least count of 3.2x101cfu/ml. Total heterotrophic bacteria and total coliform count decreased gradually in all brands throughout this period. Escherichia coli was isolated in three brands. Results from the research indicates that 60% of the brands analyzed met the WHO guideline limit for drinking when stored at ambient temperature within eight weeks period. However, storage beyond this period led to diminished potability of sachet water

Bioremediation Potential of Rhodococcus pyridinivorans NT2 in Nitrotoluene-Contaminated Soils: The Effectiveness of Natural Attenuation, Biostimulation and Bioaugmentation Approaches

ABSTRACTThis work evaluated the effect of bioremediation treatments including natural attenuation, bioaugmentation, biostimulation as well as combined biostimulation and bioaugmentation on degradation of 4-nitrotoluene (4-NT), 2,4-dinitrotoluene (2,4-DNT) and 2,6-dinitrotoluene (2,6-DNT) in soil microcosms. Bioaugmentation with a previously isolated NTs-degrading bacterium, Rhodococcus pyridinivorans NT2, showed an 86–88% decrease in 4-NT, 2,4-DNT or 2,6-DNT after 60 days. Irrespective of the substrate types, least degradation (6–6.5%) was observed in abiotic control. The addition of β-cyclodextrin or rhamnolipid significantly improved NTs degradation efficiency in soil (18.5–74%) than natural attenuation (22–25%). Exogenous addition of preselected bacterial isolate NT2 along with β-cyclodextrin/rhamnolipid resulted in the greatest number (1.8× and 2.5× high) of total heterotrophic aerobic bacteria and NT degraders, respectively, compared to natural attenuation. Irrespective of the treatment types, the population of NT degraders increased steadily in the first 5 weeks of incubation followed by a plateau within the next few weeks. The treatment BABS2 (Soil + rhamnolipid + NT2) yielded highest microbial-C and -N and dehydrogenase activity, consistent with results of NTs degradation and microbial counts in combined bioaugmentation and biostimulation. Thus the results of this study suggest that bioaugmentation by R. pyridinivorans NT2 may be a promising bioremediation strategy for nitroaromatics-contaminated soils.

Enhancing antimicrobial properties of fly ash mortars specimens through nanophase modification

Three different types of nanophase modified fly ash mortar specimens were prepared to evaluate the antimicrobial properties in seawater. Two percentage of OPC was replaced by 50-80nm and 50-70nm sized TiO2 (FAT) and CaCO3 (FAC) nanoparticles respectively. In the third type of mortar specimens a 2% of the OPC was replaced by mixture of both nanoparticles in same ratio (FATC). All the nanophase modified specimens along with FA specimens were cured in water for 28 days and exposed in seawater for a month. Specimens were withdrawn at different intervals for post-exposure analysis. Detailed microbiological characterization involving density of total heterotrophic aerobic bacteria, slime formers, anaerobic bacteria, manganese-oxidizing bacteria, fungus, sulfur oxidizing bacteria and biofilm imaging using epifluorescence microscopy, total dissolved and suspended solids in biofilm were carried out. pH reduction of the surface of the specimens were measured by flat surface electrode. Results demonstrated lesser pH reduction and enhanced antibacterial activity on the surface of FAT and FATC mortar specimens under the influence of TiO2 nanoparticles.

Occurrence of hydrocarbon degrading bacteria in soil in Kukawa, Borno State

Soil samples were collected from five sites covering petroleum exploration station in Kukawa, Kukawa Local Government Area of Borno State, Nigeria between October, 2012 and February, 2013 at two different depths (0-10cm and 10-20cm) to enumerate and identify hydrocarbon degrading bacteria in the soil. Total aerobic heterotrophic bacteria (TAHB) were enumerated on Nutrient agar (NA), and Hydrocarbon utilizing bacteria (HUB) enumerated on Oil agar (OA). The bacterial isolates were identified using morphological and biochemical tests. It was observed that the microorganisms (TAHB, and HUB) were more densely populated at 10cm depth. (TAHB: 5.3×108 - 11.4×108cfu/g, and HUB: 2.4×105 - 5.3×105 cfu/g, than at 20 cm depth (TAHB: 3.0×108 - 5.7×108 cfu/g, and HUB: 2.1×105 - 4.8×105 cfu/g). The HUB was identified as species of Bacillus, Pseudomonas, Klebsiella, Lactobacillus, Micrococcus, Corynebacterium, and Actinomyces. Bacillus, and Pseudomonas species were more constantly isolated than other isolates and they constitute 100% of total bacterial isolates. The potential of hydrocarbon utilizing bacteria isolated to degrade hydrocarbon was studied. Nineteen (19) bacterial species was screened, Bacillus subtilis, Pseudomonas aeruginosa, Bacillus cereus, Klebsiella pneumoniae, Micrococcus leteus,and Lactobacillus casei, utilized and degrade crude oil at considerably high rates after 21 days of incubation. The degradation efficiency was confirmed by GC-MS analysis, which indicated that the bacterial isolates utilized most of the crude oil components particularly straight chain alkanes and cycloalkanes DOI: http://dx.doi.org/10.3126/ije.v3i2.10503 International Journal of the Environment Vol.3(2) 2014: 36-47

Management induced changes of antibiotic resistant strains of heterotrophic bacteria in shrimp farming ponds

Antibiotic resistant strains of heterotrophic bacteria and total aerobic heterotrophic bacteria were enumerated along with important water quality parameters in water and sediment samples collected from 3 shrimp farming ponds used for the monoculture of Penaeus monodon as well as from a control pond located outside the shrimp farm. The resistant strains of heterotrophic bacteria were screened against 3 antibiotics (ampicillin, chloramphenicol and oxytetracycline) at 25 and 50 μg/l. The counts of antibiotic resistant bacteria tended to rise in shrimp ponds with progressive rise in the days of culture, but were specially high during the period when both antibiotics and feed were applied in the system. It appears that antibiotics exerted a selective pressure in favour of antibiotic resistant bacterial strains and widespread use of antibiotics should be forbidden in shrimp ponds.

Assessment of &lt;i&gt;in-situ&lt;/i&gt; abundance dynamics of enterobacteria and total heterotrophic aerobic bacteria in groundwater in the equatorial region of Central Africa

Assessment of &lt;i&gt;in-situ&lt;/i&gt; abundance dynamics of enterobacteria and total heterotrophic aerobic bacteria in groundwater in the equatorial region of Central Africa

Investigating water meter performance in developing countries: A case study of Kampala, Uganda

The main purpose of this investigation was to assess, in situ, the hourly abundance dynamics of enterobacteria and total heterotrophic aerobic bacteria (THAB), over a daily period, in 3 wells in Yaounde region, Cameroon. Sampling was done weekly, for 4 months. Water samples were collected in sterile glass bottles and incubated in situ for 2 h, 4 h, 6 h, 8 h, 10 h and 12 h. Isolation and enumeration of enterobacteria and THAB were performed on MacConkey agar (Bio-Rad) and standard agar (Bio-Rad) media, respectively, using the plate count method. Using a linear regression model, ln(number of CFUs) was plotted against time. The slope of each regression line was considered as the apparent increase or decrease in cell number. Concentrations of THAB and enterobacteria varied from 9.90 to 14.19 and 4.09 to 9.59 ln units·ml-1, respectively, in W1, from 9.90 to 14.25 and 3.00 to 5.39 ln units·ml-1 in W2, and from 9.90 to 14.00 and 6.55 to 11.51 ln units·ml-1 in W3. For the first 6-hour incubation period at all of the sampling points, the cell apparent growth rate (CAGR) varied from 0.023 to 0.262 h-1 for THAB and from 0.001 to 0.315 h-1 for enterobacteria; cell apparent inhibition rate (CAIR) varied from 0.015 to 0.615 h-1 for THAB and from 0.015 to 0.604 h-1 for enterobacteria. In the second 6-h incubation period, the CAGR varied from 0.010 to 0.822 h-1 for THAB and from 0.015 to 0.771 h-1 for enterobacteria; the CAIR varied from 0.015 to 0.260 h-1 for THAB and from 0.007 to 0.338 h-1 for enterobacteria. The values of physico-chemical parameters recorded before incubation displayed temporal and spatial variation over the sampling period. Bacterial abundance dynamics in some cases was significantly correlated to some of these abiotic factors. The abundance of the microorganisms decreased initially but later increased.

Antimicrobial Effects of Essential Oils ofCinnamosma fragranson the Bacterial Communities in the Rearing Water ofPenaeus monodonLarvae

Farmed shrimps are vectors of various Vibrio species that are considered a potential health hazard. Previous study has shown that Vibrio parahaemolyticus, Vibrio vulnificus, and Vibrio alginolyticus dominated in the water and larval samples of shrimp hatchery (Randrianarivelo et al. 2010 ). The effects of two essential oils (EOs) of Cinnamosma fragrans, an endemic plant to Madagascar (B8: linalool-type and B143: 1,8-cineole-type), were determined on the total heterotrophic aerobic bacteria and the Vibrio concentrations in the rearing water of Penaeus monodon hatchery. The assays took place in OSO Farming's shrimp hatchery in Madagascar. EOs were directly added to the water tank. The bacterial concentrations of water tank were assessed on marine agar and thiosulfate citrate bile sucrose agar. The larvae culture corresponded to four replicates each of B8, B143, erythromycin (E), and control (oil and antibiotic free). The bacterial concentration of the rearing water in B8, B143, and antibiotic (E) tanks were significantly lower (p < 0.05) than in the control. Further, there was no significant difference (p > 0.05) between the three treatments B8, B143, and E. This study demonstrated that both EOs of C. fragrans, like antibiotic, inhibited bacterial growth in the rearing water of P. monodon larvae. The potential of C. fragrans EO to control the bacterial load in in vivo conditions of P. monodon hatchery makes it a relevant option for producers to minimize risk of Vibrio growth in the rearing water of larvae, which is the primary source of colonization of shrimp larvae.

Bacterial Contamination of Surface Water in and Around Beed District, Maharashtra, India

The drinking, dams and rivers water in the Beed district of Maharashtra, India area has been studied in three different seasons. The bacterial parameters like Total aerobic Heterotrophic Bacteria (THB), Total Coliform Count (TCC) and Faecal Coliform Count (FCC) have been monitored. In water samples from all the sites, bacterial count exceeded the recommended permissible level of WHO. The TCC and FCC also crossed the permissible limits prescribed by BIS. Pathogenic bacteria were isolated from the water samples. Introduction of sewage into the surface water was the main reason for the bacterial contamination. Various techniques for this destruction/removal of pathogenic bacteria are therefore advisable before consumption. Bacterial Contamination of Surface Water in and Around Beed District, Maharashtra, India