Assessment of the prevalence of faecal coliforms and Escherichia coli o157:h7 in the final effluents of two wastewater treatment plants in Amahlathi Local Municipality of Eastern Cape Province, South Africa
- Authors: Ajibade, Adefisoye Martins
- Date: 2014
- Subjects: Sewage disposal plants , Escherichia coli -- South Africa -- Eastern Cape , Escherichia coli O157:H7 , Escherichia coli , Effluent quality -- Testing , Whole effluent toxicity testing , Water -- Purification
- Language: English
- Type: Thesis , Masters , MSc (Microbiology)
- Identifier: vital:11283 , http://hdl.handle.net/10353/d1016166 , Sewage disposal plants , Escherichia coli -- South Africa -- Eastern Cape , Escherichia coli O157:H7 , Escherichia coli , Effluent quality -- Testing , Whole effluent toxicity testing , Water -- Purification
- Description: The production of final effluents that meet discharged requirements and guidelines remain a major challenge particularly in the developing world with the resultant problem of surface water pollution. This study assessed the physicochemical and microbiological qualities of two wastewater treatment works in the Eastern Cape Province of South Africa in terms of the prevalence of faecal coliforms and Escherichia coli O157:H7 over a five month period. All physicochemical and microbiological analyses were carried out using standard methods. Data were collected in triplicates and analysed statistically using IBM SPSS version 20.0. The ranges of some of the physicochemical parameters that complied with set guidelines include pH (6.7 – 7.6), TDS (107 – 171 mg/L), EC (168 – 266 μS/cm), Temperature (15 – 24oC), NO3- (0 – 8.2 mg/L), NO2- (0.14 – 0.71 mg/L) and PO4 (1.05 – 4.50 mg/L). Others including Turbidity (2.64 – 58.00 NTU), Free Cl (0.13 – 0.65 mg/L), DO (2.20 – 8.48 mg/L), BOD (0.13 – 6.85 mg/L) and COD (40 – 482 mg/L) did not comply with set guidelines. The microbiological parameters ranged 0 – 2.7 × 104 CFU/100 ml for FC and 0 – 9.3 × 103 for EHEC CFU/100 ml, an indication of non-compliance with set guidelines. Preliminary identification of 40 randomly selected presumptive enterohemorrhagic E. coli isolates by Gram’s staining and oxidase test shows 100% (all 40 selected isolates) to be Gram positive while 90% (36 randomly selected isolates) were oxidase negative. Statistical correlation between the physicochemical and the microbiological parameters were generally weak except in the case of free chlorine and DO where they showed inverse correlation with the microbiological parameters. The recovery of EHEC showed the inefficiency of the treatment processes to effectively inactivate the bacteria, and possibly other pathogenic bacteria that may be present in the treated wastewater. The assessment suggested the need for proper monitoring and a review of the treatment procedures used at these treatment works.
- Full Text:
- Authors: Ajibade, Adefisoye Martins
- Date: 2014
- Subjects: Sewage disposal plants , Escherichia coli -- South Africa -- Eastern Cape , Escherichia coli O157:H7 , Escherichia coli , Effluent quality -- Testing , Whole effluent toxicity testing , Water -- Purification
- Language: English
- Type: Thesis , Masters , MSc (Microbiology)
- Identifier: vital:11283 , http://hdl.handle.net/10353/d1016166 , Sewage disposal plants , Escherichia coli -- South Africa -- Eastern Cape , Escherichia coli O157:H7 , Escherichia coli , Effluent quality -- Testing , Whole effluent toxicity testing , Water -- Purification
- Description: The production of final effluents that meet discharged requirements and guidelines remain a major challenge particularly in the developing world with the resultant problem of surface water pollution. This study assessed the physicochemical and microbiological qualities of two wastewater treatment works in the Eastern Cape Province of South Africa in terms of the prevalence of faecal coliforms and Escherichia coli O157:H7 over a five month period. All physicochemical and microbiological analyses were carried out using standard methods. Data were collected in triplicates and analysed statistically using IBM SPSS version 20.0. The ranges of some of the physicochemical parameters that complied with set guidelines include pH (6.7 – 7.6), TDS (107 – 171 mg/L), EC (168 – 266 μS/cm), Temperature (15 – 24oC), NO3- (0 – 8.2 mg/L), NO2- (0.14 – 0.71 mg/L) and PO4 (1.05 – 4.50 mg/L). Others including Turbidity (2.64 – 58.00 NTU), Free Cl (0.13 – 0.65 mg/L), DO (2.20 – 8.48 mg/L), BOD (0.13 – 6.85 mg/L) and COD (40 – 482 mg/L) did not comply with set guidelines. The microbiological parameters ranged 0 – 2.7 × 104 CFU/100 ml for FC and 0 – 9.3 × 103 for EHEC CFU/100 ml, an indication of non-compliance with set guidelines. Preliminary identification of 40 randomly selected presumptive enterohemorrhagic E. coli isolates by Gram’s staining and oxidase test shows 100% (all 40 selected isolates) to be Gram positive while 90% (36 randomly selected isolates) were oxidase negative. Statistical correlation between the physicochemical and the microbiological parameters were generally weak except in the case of free chlorine and DO where they showed inverse correlation with the microbiological parameters. The recovery of EHEC showed the inefficiency of the treatment processes to effectively inactivate the bacteria, and possibly other pathogenic bacteria that may be present in the treated wastewater. The assessment suggested the need for proper monitoring and a review of the treatment procedures used at these treatment works.
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Molecular study of mycobacterium tuberculosis complex (MTBC) DNA from Port Elizabeth
- Authors: Londiwe, Bhembe Nolwazi
- Date: 2014
- Subjects: Mycobacterium tuberculosis
- Language: English
- Type: Thesis , Masters , MSc (Microbiology)
- Identifier: vital:11281 , http://hdl.handle.net/10353/d1016163 , Mycobacterium tuberculosis
- Description: Mycobacterium tuberculosis complex (MTBC) is a causative agent of tuberculosis (TB) in humans and animals. The burden of tuberculosis in South Africa is worsened by the concurrent epidemic of HIV. The dynamic of TB epidemics has been investigated and yet little data has been given about the Eastern Cape, particularly Port Elizabeth. The study aimed to investigate the prevalence of drug resistant MTBC and to determine the mutations causing resistance in Port Elizabeth. One hundred and ninety (190) DNA samples isolated from sputum specimen in humans suspected of having TB were amplified using the Seeplex® MTB Nested ACE detection assay. To differentiate Mycobacterium tuberculosis complex (MTBC) members for surveillance purposes a multiplex polymerase chain reaction (PCR) method was done based on genomic regions of differences such as RD1, RD1mic, RD2seal, RD4, RD9 and RD12. Target genes known to confer resistance to first and second-line drugs were amplified and the amplicons sequenced using Big Dye Terminator DNA sequencing kit v3.1 (Applied Biosystems, UK). The patient’s demographic profiles were obtained from the National Health Laboratory Service (NHLS). All hundred and ninety DNA samples tested positive for MTBC using the Seeplex® MTB Nested ACE assay. Results show a high prevalence of extensive drug resistant TB in Port Elizabeth, Eastern Cape Province. One hundred and eighty four (184) DNA isolates were used in the identification of different MTBC species. We ended up working with 184 DNA isolates because we ran out of DNA, and we could not go back to isolate DNA from the affected individuals due to the fact that some patients died, while some have been released to go to their homes. From the 184 DNA isolates 45 (24.5%) isolates were identified to be M. tuberculosis, 94 isolates (51.1%) to be M. bovis BCG and 3 isolates (1.6%) to be M. cannetti. Sequencing results show the position of mutation in each DNA isolate; however in the study we got resistance to MDR to be 100% and 42% pre-XDR while 58% was XDR. These results raise an alarm for the prevalence MDR in MTBC from Port Elizabeth. This is a serious health concern which calls for a need to strategise on the identification of extensive drug resistant TB patients from multi-drug resistant TB patients and ensure monitoring of their treatment.
- Full Text:
- Authors: Londiwe, Bhembe Nolwazi
- Date: 2014
- Subjects: Mycobacterium tuberculosis
- Language: English
- Type: Thesis , Masters , MSc (Microbiology)
- Identifier: vital:11281 , http://hdl.handle.net/10353/d1016163 , Mycobacterium tuberculosis
- Description: Mycobacterium tuberculosis complex (MTBC) is a causative agent of tuberculosis (TB) in humans and animals. The burden of tuberculosis in South Africa is worsened by the concurrent epidemic of HIV. The dynamic of TB epidemics has been investigated and yet little data has been given about the Eastern Cape, particularly Port Elizabeth. The study aimed to investigate the prevalence of drug resistant MTBC and to determine the mutations causing resistance in Port Elizabeth. One hundred and ninety (190) DNA samples isolated from sputum specimen in humans suspected of having TB were amplified using the Seeplex® MTB Nested ACE detection assay. To differentiate Mycobacterium tuberculosis complex (MTBC) members for surveillance purposes a multiplex polymerase chain reaction (PCR) method was done based on genomic regions of differences such as RD1, RD1mic, RD2seal, RD4, RD9 and RD12. Target genes known to confer resistance to first and second-line drugs were amplified and the amplicons sequenced using Big Dye Terminator DNA sequencing kit v3.1 (Applied Biosystems, UK). The patient’s demographic profiles were obtained from the National Health Laboratory Service (NHLS). All hundred and ninety DNA samples tested positive for MTBC using the Seeplex® MTB Nested ACE assay. Results show a high prevalence of extensive drug resistant TB in Port Elizabeth, Eastern Cape Province. One hundred and eighty four (184) DNA isolates were used in the identification of different MTBC species. We ended up working with 184 DNA isolates because we ran out of DNA, and we could not go back to isolate DNA from the affected individuals due to the fact that some patients died, while some have been released to go to their homes. From the 184 DNA isolates 45 (24.5%) isolates were identified to be M. tuberculosis, 94 isolates (51.1%) to be M. bovis BCG and 3 isolates (1.6%) to be M. cannetti. Sequencing results show the position of mutation in each DNA isolate; however in the study we got resistance to MDR to be 100% and 42% pre-XDR while 58% was XDR. These results raise an alarm for the prevalence MDR in MTBC from Port Elizabeth. This is a serious health concern which calls for a need to strategise on the identification of extensive drug resistant TB patients from multi-drug resistant TB patients and ensure monitoring of their treatment.
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Synthesis, characterization & comparative evaluation of photo-catalytic & antimicrobial activity of Ag2O and TiO2 immobilized on nanofibres for treatment
- Authors: Gxumisa, Xoliswa
- Date: 2014
- Subjects: Pollution http://id.loc.gov/authorities/subjects/sh85104530 , Titanium dioxide http://id.loc.gov/authorities/subjects/sh85135627 , Photocatalysis http://id.loc.gov/authorities/subjects/sh93001301
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/19545 , vital:43138
- Description: Water is a very essential substance for the existence of organisms and the environment where it functions as a transport medium for valuable chemicals, minerals, nutrients and also as a reaction medium. However, the remarkable water properties are not just limited to the dissolution of biological valuable substances, but also to harmful entities during pollution. This has led to research in the improvement and development of new techniques for water treatment. In this study, titanium dioxide (TiO2) and silver oxide (Ag2O) were prepared using the sol gel process and precipitation method respectively. The TiO2 was doped using a sol gel process with carbon and nitrogen so as to reduce the band gap. TiO2/Ag2O, N-TiO2/Ag2O and C-TiO2/Ag2O composites were also prepared using a precipitation method. The average particle size of prepared TiO2, C-TiO2, N-TiO2, Ag2O, TiO2/Ag2O, N-TiO2/Ag2O and CTiO2/Ag2O was found to be 13nm, 7nm, 10nm, 23nm, 28nm, 24nm and 21nm respectively as measured by TEM analysis. The photo-catalysts, Ag2O and TiO2 and their composites were immobilized on stabilized nanofibres using the electrospinning process to allow subsequent separation and reconciliation of the photo-catalyst after use in water treatment. The photocatalytic and antimicrobial activities of photo-catalysts were also evaluated using water contaminated with phenol red dye and Escherichia coli. The prepared materials were characterized by XRD, TEM, HRSEM, DRS, EDX, FT-IR, and TGA. Carbon was found to be more effective as a dopant than nitrogen. It reduced the band gap by 0.4 while nitrogen doping showed a reduction in band gap of 0.2 compared to undoped titanium dioxide. The doped TiO2 exhibited higher photo-catalytic and antimicrobial activity than the undoped TiO2. Introduction of Ag2O allowed utilization of visible light by the TiO2- Ag2O nano-composite leading to an improved rate of photo-degradation of phenol red and inactivation of E coli. Photo-catalytic properties showed that carbon doped materials have a higher photo-catalytic activity than nitrogen doped materials, while for antimicrobial v properties it is vice-versa. The immobilization of photo-catalysts on support material made it less effective towards the degradation of phenol red. The rate of photo-oxidation of phenol red was three times faster using powder TiO2 compared to immobilized TiO2. Therefore, this study suggests that photo-catalysis can be used as an effective method for water disinfection and production of potable and pathogen free drinking water even though better methods of immobilization should be sought. , Thesis (MSc) (Chemistry) -- University of Fort Hare, 2014
- Full Text:
- Authors: Gxumisa, Xoliswa
- Date: 2014
- Subjects: Pollution http://id.loc.gov/authorities/subjects/sh85104530 , Titanium dioxide http://id.loc.gov/authorities/subjects/sh85135627 , Photocatalysis http://id.loc.gov/authorities/subjects/sh93001301
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/19545 , vital:43138
- Description: Water is a very essential substance for the existence of organisms and the environment where it functions as a transport medium for valuable chemicals, minerals, nutrients and also as a reaction medium. However, the remarkable water properties are not just limited to the dissolution of biological valuable substances, but also to harmful entities during pollution. This has led to research in the improvement and development of new techniques for water treatment. In this study, titanium dioxide (TiO2) and silver oxide (Ag2O) were prepared using the sol gel process and precipitation method respectively. The TiO2 was doped using a sol gel process with carbon and nitrogen so as to reduce the band gap. TiO2/Ag2O, N-TiO2/Ag2O and C-TiO2/Ag2O composites were also prepared using a precipitation method. The average particle size of prepared TiO2, C-TiO2, N-TiO2, Ag2O, TiO2/Ag2O, N-TiO2/Ag2O and CTiO2/Ag2O was found to be 13nm, 7nm, 10nm, 23nm, 28nm, 24nm and 21nm respectively as measured by TEM analysis. The photo-catalysts, Ag2O and TiO2 and their composites were immobilized on stabilized nanofibres using the electrospinning process to allow subsequent separation and reconciliation of the photo-catalyst after use in water treatment. The photocatalytic and antimicrobial activities of photo-catalysts were also evaluated using water contaminated with phenol red dye and Escherichia coli. The prepared materials were characterized by XRD, TEM, HRSEM, DRS, EDX, FT-IR, and TGA. Carbon was found to be more effective as a dopant than nitrogen. It reduced the band gap by 0.4 while nitrogen doping showed a reduction in band gap of 0.2 compared to undoped titanium dioxide. The doped TiO2 exhibited higher photo-catalytic and antimicrobial activity than the undoped TiO2. Introduction of Ag2O allowed utilization of visible light by the TiO2- Ag2O nano-composite leading to an improved rate of photo-degradation of phenol red and inactivation of E coli. Photo-catalytic properties showed that carbon doped materials have a higher photo-catalytic activity than nitrogen doped materials, while for antimicrobial v properties it is vice-versa. The immobilization of photo-catalysts on support material made it less effective towards the degradation of phenol red. The rate of photo-oxidation of phenol red was three times faster using powder TiO2 compared to immobilized TiO2. Therefore, this study suggests that photo-catalysis can be used as an effective method for water disinfection and production of potable and pathogen free drinking water even though better methods of immobilization should be sought. , Thesis (MSc) (Chemistry) -- University of Fort Hare, 2014
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