Browsing by Author "Pool, Edmund John"

Now showing 1 - 6 of 6
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    The effectiveness of sewage treatment processes to remove faecal pathogens and antibiotic residues
    (TAYLOR & FRANCIS INC, 2013) Hendricks, Rahzia; Pool, Edmund John
    Pathogens and antibiotics enter the aquatic environment via sewage effluents and may pose a health risk to wild life and humans.The aim of this study was to determine the levels of faecal bacteria, and selected antibiotic residues in raw wastewater and treatedsewage effluents from three different sewage treatment plants in the Western Cape, South Africa. Sewage treatment plant 1 and 2 useolder technologies, while sewage treatment plant 3 has been upgraded and membrane technologies were incorporated in the treatmentprocesses. Coliforms andEscherichia coli(E. coli) were used as bioindicators for faecal bacteria. A chromogenic test was used toscreen for coliforms andE. coli. Fluoroquinolones and sulfamethoxazole are commonly used antibiotics and were selected to monitorthe efficiency of sewage treatment processes for antibiotic removal. Enzyme Linked Immunosorbent Assays (ELISAs) were used toquantitate antibiotic residues in raw and treated sewage. Raw intake water at all treatment plants contained total coliforms andE. coli.High removal ofE. coliby treatment processes was evident for treatment plant 2 and 3 only. Fluoroquinolones and sulfamethoxazolewere detected in raw wastewater from all sewage treatment plants. Treatment processes at plant 1 did not reduce the fluoroquinoloneconcentration in treated sewage effluents. Treatment processes at plant 2 and 3 reduced the fluoroquinolone concentration by 21%and 31%, respectively. Treatment processes at plant 1 did not reduce the sulfamethoxazole concentration in treated sewage effluents. Treatment processes at plant 2 and 3 reduced sulfamethoxazole by 34% and 56%, respectively. This study showed that bacteria and antibiotic residues are still discharged into the environment. Further research needs to be undertaken to improve sewage treatmenttechnologies, thereby producing a better quality treated sewage effluent.
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    Effects of graphene oxide nanoparticles on the immune system biomarkers produced by RAW264.7 and human whole blood cell cultures
    (MDPI, 2018) Lategan, Kim; Alghadi, Hend; Bayati, Mohamed; de Cortalezzi, Maria Fidalgo; Pool, Edmund John
    Graphene oxide nanoparticles (GONPs) have attracted a lot of attention due to their many applications. These applications include batteries, super capacitors, drug delivery and biosensing. However, few studies have investigated the effects of these nanoparticles on the immune system. In this study, the in vitro effects of GONPs on the immune system was evaluated by exposing murine macrophages, RAW 264.7 cells and human whole blood cell cultures (to GONPs. The effects of GONPs on RAW cells were monitored under basal conditions. The whole blood cell cultures were exposed to GONPs in the presence or absence of the mitogens lipopolysaccharide (LPS) and phytohaemmagglutinin (PHA). A number of parameters were monitored for both RAWand whole blood cell cultures, these included cytotoxicity, inflammatory biomarkers, cytokines of the acquired immune system and a proteome profile analysis. The GONPs were cytotoxic to both RAW and whole blood cell cultures at 500 g/mL. In the absence of LPS, GONPs elicited an inflammatory response from the murine macrophage, RAW and whole blood cell cultures at 15.6 and 5 g/mL respectively. This activation was further corroborated by proteome profile analysis of both experimental cultures. GONPs inhibited LPS induced interleukin 6 (IL-6) synthesis and PHA induced interferon gamma (IFN ) synthesis by whole blood cell cultures in a dose dependent manner. In the absence of mitogens, GONPs stimulated IL-10 synthesis by whole blood cell cultures. The current study shows that GONPs modulate immune system biomarkers and that these may pose a health risk to individuals exposed to this type of nanoparticle.
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    The in vitro effects of artificial and natural sweeteners on the immune system using whole blood culture assays
    (Taylor & Francis, 2013) Rahiman, Farzana; Pool, Edmund John
    This article investigates the effects of commercially available artificial (aspartame, saccharin, sucralose) and natural sweeteners (brown sugar, white sugar, molasses) on the immune system. Human whole blood cultures were incubated with various sweeteners and stimulated in vitro with either phytohemagglutinin or endotoxin. Harvested supernatants were screened for cytotoxicity and cytokine release. Results showed that none of the artificial or natural sweeteners proved to be cytotoxic, indicating that no cell death was induced in vitro. The natural sweetener, sugar cane molasses (10 ug=mL), enhanced levels of the inflammatory biomarker IL-6 while all artificial sweeteners (10 ug=mL) revealed a suppressive effect on IL-6 secretion (P<0.001). Exposure of blood cells to sucralose-containing sweeteners under stimulatory conditions reduced levels of the biomarker of humoral immunity, Interleukin-10 (P<0.001). The cumulative suppression of Interleukin-6 and Interleukin-10 levels induced by sucralose may contribute to the inability in mounting an effective humoral response when posed with an exogenous threat.
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    Oestrogen, testosterone, cytotoxin and cholinesterase inhibitor removal during reclamation of sewage to drinking water
    (Water Research Commission, 2013) Faul, A.K.; Julies, E.; Pool, Edmund John
    Namibia is the driest sub-Saharan country in Africa. Namibia’s capital, Windhoek, reclaims sewage water for domestic use at the Goreangab Water Reclamation Plant (GWRP). Risks associated with sewage effluent and reclaimed sewage should be closely monitored; therefore water at the Gammams Sewage Treatment Plant (GSTP) inlet and outlet, as well as reclaimed water from the GWRP, were assayed using selected bioassays. Samples collected were analysed using enzyme-linked immunosorbent-assays and chromogenic tests for steroid hormones, neurotoxicity, cytotoxicity and inflammatory activity. Estradiol level at the sewage treatment inlet was 78 pg/mℓ and the treated sewage level showed an 83% to 95% reduction in this, while after reclamation the level was below detection limit. Estrone concentrations at the sewage treatment inlet ranged from 10 to 161 pg/mℓ. Sewage treatment reduced estrone by between 85% and 92%. After reclamation the level of estrone was below detection limit. Testosterone ranged between 162 and 405 pg/mℓ at the sewage plant inlet. Sewage treatment removed 96% of the initial testosterone. The residual testosterone was effectively removed by processes in GWRP and after reclamation no testosterone was detected in water. Acetylcholinesterase (AChE) inhibition at the sewage treatment inlet was 50% while it was only 27% after sewage treatment. After reclamation AChE inhibition was not detected. Only water at the sewage inlet in March and February showed cytotoxicity. High inflammatory activity was detected at the sewage plant inlet. Sewage treatment reduced inflammatory activity by 64%. After reclamation low inflammatory activity was induced. Treated sewage used for reclamation tested positive for most of the biomarkers and can pose a risk to human health. However, reclamation successfully removed these contaminants. Due to the presence of contaminants in the intake water at the reclamation plant, it is essential to routinely monitor the water produced by the reclamation plant for potential residues that can adversely affect human health.
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    Preliminary study on the effect of sugar cane (Saccharum officinarum) molasses on steroidogenesis in testicular cell cultures
    (Academic Journals, 2010) Rahiman, Farzana; Pool, Edmund John
    Blackstrap molasses has been used for centuries in the preparation of food products and have also been used to treat numerous ailments such as high blood pressure, arthritis, ulcers, dermatitits, eczema, constipation, colitis, varicose veins and many other health problems. Reports suggest that blackstrap molasses may have endocrine disruptive effects in cattle. The present study investigated the effect of sugar cane (Saccharum officinarium) molasses on steroidogenesis in testis cell culture. Testis cell cultures were incubated with various concentrations of molasses. Luteinizing hormone was used to stimulate the production of testosterone in the testes cell culture. Supernatants of the testes cell cultures were then assayed for testosterone, oestradiol and cytotoxicity using commercially available kits. Results showed that low concentrations (12 - 50 ug/ml) of molasses increase testosterone secretion relative to control cultures (P < 0.05). None of the molasses concentrations tested were cytotoxic. This study has shown that molasses stimulate testosterone production. Therefore, molasses may potentially be used as a diet supplement to increase testosterone levels.
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    Seasonal variation of citrinin in traditionally brewed African beer
    (Academic Journals, 2013) Ikalafeng, B.K.; Pool, Edmund John; Lues, R.; Groenewald, W.H.
    A seasonal study on citrinin concentrations in traditional beer was conducted using a standardised enzyme-linked immunosorbent assay. Representative samples of indigenous South African beer were collected during the hot, mild and cold seasons from marginal-urban settlements in the Kimberley area, South Africa. The mean temperature and humidity readings were 37C and 29% for respectively summer, 19.4C and 7.1% for spring, and 16.3C and 6.5% for winter. Samples were analysed for the mycotoxincitrinin using a commercial Ridascreen (citrinin) ELISA kit, validated for the purpose of the study. The recovery level achieved for citrinin in beer samples using the kit was 117 + - 15%. The inter-assay and intra-assay variations were 17.8 and 14.8% respectively. Standard curves prepared using traditional beer samples were similar to the standard curves prepared using the kit standards. The mean citrinin concentrations found in the various samples were 257.6 ug/kg, 99.0 and 185.7 ug/kg for the summer, spring and winter seasons respectively and the levels ranged between 35.6 ug/kg (min) and 924.2 ug/kg (max). Statistically significant differences (p ?0.05) were found between the citrinin levels of the summer and spring samples and also between citrinin levels of the spring and winter samples (p ?0.001). The relatively high levels of citrinin in selected samples may, with prolonged exposure, have adverse impacts on the health of consumers. Thus further studies into the origin and levels of this mycotoxin should be a priority.