<p>African medicinal plants are commonly used throughout Africa to treat a variety of ailments including wounds and ulcers, cough and chest complaints, gingivitis, fever and gonorrhoea, indication all related to infection and inflammation. In screening several plant species from an inventory of common medicinal plants from both South and West Africa for diverse medicinal purposes, 6 plants were selected because of their interesting and useful ethnomedicinal values.</p>

The current study investigated application of natural adsorbents in brine treatment. Brines are hypersaline waters generated in power stations and mining industries rich in Mg2+, K+, Ca2+, Na+, SO4 2- , Cl- and traces of heavy metals, thus there is a need for these brines to be treated to recover potable water and remove problematic elements. Natural adsorbents have been successfully used in waste water treatment because of their high surface area and high adsorptive properties when they are conditioned with acid or base. The investigation of pH showed that natural adsorbents did not perform well at low pH of 4 and 6. The adsorbents were able to work efficiently at the natural pH of 8.52 of the brine solution. These results show that natural adsorbents hold great potential to remove cationic major components and selected heavy metal species from industrial brine wastewater. Heterogeneity of natural adsorbents samples, even when they have the same origin, could be a problem when wastewater treatment systems utilizing natural clinoptilolite and bentonite are planned to be developed. Therefore, it is very important to characterize the reserves fully in order to make them attractive in developing treatment technologies.

According to the Department of Water Affairs (DWAF, 2004 p.15), South Africa’s water resources are scarce and extremely limited and much of this precious resource is utilised and consumed in our industries. Treatment and re-use of effluent generated is, in some cases, preferred over use of alternate water resources (Du Plessis, 2008 p.3). The volume of effluent generated in treatment processes like ultra-filtration (UF) and reverse osmosis (RO) units is determined by the feed water quality, with high water loss through effluent generation at poor feed water quality. Current UF and RO applications require an increased UF production capacity due to the use of UF filtrate for periodic backwashing of the UF membrane units. This results in loss of water and decreases overall recovery. The need therefore exists to increase the overall recovery of product water from the raw water stream by reducing the amount of effluent generated. This would be possible to achieve by using RO brine to backwash the UF unit. The study was conducted to provide a modelling tool, assisting management to optimise the use of RO brine as backwash water on the UF system at the Medupi power station. The secondary objective of this study was the development of a modelling tool that can be used for other projects, new or existing, as a measure and indication of the usability of RO brine as backwash water on UF systems. By successfully applying this newly developed model, the viability of utilising the RO brine as backwash water for the UF was investigated. This modification would lead to utilizing smaller UF units than previously envisioned, which in turn leads to reducing capital cost with 11.07% and operating expenditure with 9.98% at the Medupi power station. This also has a positive environmental impact by reducing the amount of raw water used monthly by 10.34% (108 000 m3/month). / MIng (Development and Management Engineering), North-West University, Potchefstroom Campus, 2014

Magister Scientiae - MSc (Chemistry) / Plants have been widely used in traditional medicine for a number of ailments, among which may be included infectious diseases such as colds, influenza, chicken pox, TB, etc. as well as lifestyle diseases such as diabetes and cancer. Seaweeds have also been shown to contribute to the maintenance of health through their nutritional and medicinal properties and recently, a great deal of interest has developed towards the isolation of bioactive compounds from marine sources due to their numerous health benefits. Furthermore, marine algae are valuable sources of structurally diverse metabolites with scientifically proven therapeutic claims. Chemical constituents of red seaweed, Porphyra capensis was investigated in this present study along with subsequent brine shrimp lethality assay analysis of the crude extracts. The compounds isolated from the plant were from the hexane (6) and butanol (2) extracts. These compounds were all isolated and purified by various chromatographic techniques, namely silica gel chromatography, Sephadex LH-20 gel as well as C18 reversed phase silica gel. The structures of the isolated compounds were analysed and characterised by NMR, GC-MS, ESI MS and FTIR spectroscopy. Eight compounds were isolated and identified as phytol, desmosterol, 9-eicosenoic acid, 5,8,11,14,17-eicosapentanoic acid, palmitic acid, methyl (E)-hexadec-9-enoate, glycerol and compound 1 (novel compound). All the compounds were isolated from Porphyra capensis for the first time. The hexane, butanol and methanol extracts were found to be non-toxic with the brine shrimp test LC50 value at least two times greater than ?g/ml.

Orientador: Marise Aparecida Rodrigues Pollonio / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-12T23:24:45Z (GMT). No. of bitstreams: 1 Goncalves_JoseRicardo_D.pdf: 994769 bytes, checksum: 9d34a7fca1375376263e5b61d69c9805 (MD5) Previous issue date: 2009 / Resumo: Foram estudados os efeitos da composição da salmoura (em nível de 20%) e dos regimes de cozimento na estabilidade físico-química, sensorial e microbiológica da carne bovina (M. semitendinosus), acondicionada em embalagem cook in. O estudo foi realizado em duas etapas experimentais. Na primeira etapa a carne foi injetada de modo a incorporar cloreto de sódio (1%), tripolifosfato de sódio (0,2 e 0,4%), extrato de alecrim (0,025 e 0,050%) e mistura de lactato/diacetato de sódio (0,40/0,03%), cozida à temperatura interna de 70ºC durante 60min (condição em que o sabor de requentado ocorre mais rapidamente) e armazenada a 4ºC por um período de 30 dias. Foram avaliados os efeitos sobre o pH, perda de peso no repouso, perda de peso no cozimento, rendimento de processo, cor (L*, a*, b*), força de cisalhamento, crescimento de bactérias, índice de oxidação (TBARS) e aparência e odor. Os resultados mostram que a concentração de tripolifosfato de sódio teve efeito significativo (p<0,05) no aumento do pH, na redução das perdas de peso no repouso, na redução das perdas de peso no cozimento e no aumento do rendimento de processo. O extrato de alecrim não apresentou efeito significativo (p>0,05) sobre estas repostas. Durante os 30 dias de armazenamento a 4ºC, o tempo mostrou efeito significativo (p<0,05) nas variações de pH, cor (L*, a*, b*), força de cisalhamento e no índice de TBARS. A oxidação foi mais evidente no tratamento controle (sem injeção), mas os tratamentos com injeção foram capazes de minimizar a velocidade da reação. Não foi detectada a presença de patógenos durante o período de armazenamento a 4ºC, mas apenas indícios de uma fase inicial de deterioração por psicrotróficos no último dia de avaliação. Quanto à aparência e odor, as maiores porcentagens de aceitação foram atribuídas pelos consumidores aos tratamentos sem injeção (controle) por causa da coloração característica de carne cozida. Na segunda etapa do experimento foi utilizada uma das formulações selecionadas na etapa anterior para avaliar a influencia dos regimes de cozimento com dois tempos de residência a 60ºC (60 e 120min) e duas temperaturas finais (70 e 80ºC) de processo. Os tratamentos apresentaram efeito significativo (p<0,05) sobre as respostas, sendo que os regimes de cozimento com temperatura final de 70ºC resultaram em maior rendimento de processo e menor perda de peso na cocção, independentemente do tempo de residência a 60ºC. Mas, os valores da força de cisalhamento foram numericamente muito parecidos em todos os tratamentos. Os regimes de cozimento mostraram-se potencialmente seguros quanto a destruição de células vegetativas de Listeria monocytogenes e Clostridium perfringens. Em particular, os tratamentos com temperatura interna final de 80ºC apresentaram um potencial de destruição mais drástico, capaz de eliminar a forma esporulada de Clostridium botulinum tipo E, além de e outros microrganismos de resistência térmica equivalente ou inferior. Dependendo de novos estudos, o tratamento térmico poderá reduzir a necessidade de agentes bacteriostáticos na formulação da salmoura, sem prejudicar as características de qualidade da carne bovina / Abstract: This study focuses on the effects of brine composition (at the 20% level) and cooking time and temperature on the physical-chemical, sensory and microbiological stability of bovine meat (M. semitendinosus), packed in cook in bags. The study was conducted in two experimental phases. In phase I, the meat was injected so as to incorporate sodium chloride (1%), sodium tripolyphosphate (0,2 and 0,4%), (condition in which warmed over flavor -WOF develops more rapidly) and stored at 4ºC for a period of 30 days. The study evaluated the effects on pH, weight loss (during holding at 4ºC/48h), cooking loss, process yield, color (L*, a*, b*), shear force, bacterial growth, oxidation index (TBARS), in addition to overall appearance and odor. The results show that the concentration of tripolyphosphate had a significant effect (p<0,05) on the pH increase, on the reduction of weight loss during holding, on the reduction of cooking loss and on the increase in process yield. The rosemary extract had no significant effect (p>0,05) on these parameters. During the 30 days storage at 4ºC, time was found to exert a significant effect (p<0,05) on pH variations, color (L*, a*, b*), shear force and the TBARS index. Oxidation was more evident in the control treatment (without injection), but the injection treatments were effective in minimizing the speed of the oxidation reaction. Pathogens were not detected throughout storage at 4ºC, except for slight indications of the onset of spoilage by psychrotrophic bacteria on the last day of evaluation. As for overall appearance and odor, consumers assigned the highest acceptance percentages to the treatments without injection (control) due to the typical color of cooked meat. In the second phase of the experiment, one of the formulations selected in the previous phase was used to evaluate the influence of the cooking conditions of time and temperature by testing two holding times at 60ºC (60 e 120min) and two final process temperatures (70 and 80ºC). The treatments exhibited a significant effect (p<0,05) on the parameters assessed, with the cooking processes with final temperature of 70ºC producing higher process yields and lower weight loss during cooking, irrespective of the holding temperature of 60ºC. On the other hand, the shear force values were numerically very similar across all the treatments investigated. The cooking time and temperature combinations tested were found potentially safe with respect to the destruction of vegetative cells of Listeria monocytogenes and Clostridium perfringens. Particularly the treatments with final internal temperature of 80ºC exhibited a much higher destruction potential and were found to be able to eliminate Clostridium botulinum E type spores, in addition to other microorganisms of equal or lower heat resistance. Depending on new studies, the use of appropriate heat treatments may reduce the need for bacteriostatic / Doutorado / Doutor em Tecnologia de Alimentos

Philosophiae Doctor - PhD / African medicinal plants are commonly used throughout Africa to treat a variety of ailments including wounds and ulcers, cough and chest complaints, gingivitis, fever and gonorrhoea, indication all related to infection and inflammation. In screening several plant species from an inventory of common medicinal plants from both South and West Africa for diverse medicinal purposes, 6 plants were selected because of their interesting and useful ethnomedicinal values. / South Africa

>Magister Scientiae - MSc / Research into traditional medicines is often conducted in a multidisciplinary approach as motivated by a desire to understand them in as complete a manner as possible,realizing their chemistry, biology and pharmacology. One biological approach involves monitoring the cytotoxicity of the extracts of subfractions against the nauplii,Artemia salina (brine shrimp). Organic and aqueous extracts of seven South African medicinal plants was investigated for biological activity. Selected plant extracts was also evaluated for AChE inhibitory activity. The objectives of this study was to look for any correlation between known biological activities of the investigated plants and BSLT lethality data and also to look for any correlation between AChEI activity and BSLT lethality data for selected plant extracts. The most active of the plants was the n-hex extract of T.alliacea, followed by the aqueous extract of C.mellei and the MeOH extract of C.quadrifidus; the MeOH and the DCM extracts of A.afra; the DCM extract of P.undulatum and the EtOAc extract of A.annua. The results from this study show a good correlation with antitumor, antimicrobial and anti-trypanocidal activity.The various plants extracts investigated showed good inhibitory activity towards AChE using the TLC bioautography method. The results obtained from this study indicate that this type of activity is not only subject to plants containing alkaloids, but rather a diverse class of compounds may exhibit this kind of activity. The extracts that showed good AChE inhibitory activity also showed good cytotoxicity towards brine shrimp nauplii.

Proper disposal of industrial brine has been a critical environmental challenge. Driven by the even-tightening environment protection regulations, the Zero-Liquid-Discharge (ZLD) has gradually become mandatory option for brine disposal, but its application is limited by the intensive energy consumption. The recent development of solar crystallizer provides a new strategy to achieve ZLD brine disposal. However, the research on solar crystallizer, employing photothermal material to convert solar energy to heat for interfacial brine evaporation and crystallization, is still at the early stage. This dissertation thoroughly investigated the solar crystallizer-based ZLD technology in a broad scientific and application context. The scaling formation while treating real brine, which has been the major barrier to the application of solar crystallizer, was confirmed first with a solar crystallizer device. With a rational designed anti-scaling mechanism, the scaling-free crystallization behavior and stable high water evaporation rate of 2.42 kg m-2 h-1 was achieved when treating real seawater brine. After verifying the feasibility of solar crystallizer towards real brine treatment, its performance was further improved by integrating convective airflow, which provided considerable environmental energy for water evaporation. Both experiment results and COMSOL simulation results confirmed that the maximum environmental energy harvesting can be achieved with the proper size of solar crystallizer. At last, this dissertation pioneered a novel concept of integrating adsorption process into solar crystallizer for simultaneously ZLD brine treatment and potassium extraction. Owing to the special ion concentration behavior of solar crystallizer, the adsorption capacity and selectivity coefficient of absorbent was enhanced by 19.5% and 48.8%, respectively, comparing with traditional bulk adsorption. This dissertation potentially unlocks a new generation of ZLD technology with low carbon footprint and source recovery. More research efforts will be inspired on its applications in real scenarios.

As stormwater flows over roads, sidewalks, and other impervious surfaces, it picks up pollutants that are deposited on these surfaces. One common pollutant transported by stormwater is road salt. While the application of road salt is crucial for wintertime public safety, road salt has a host of negative environmental impacts. Road salt has been linked to increasing levels of dissolved solids in groundwater, vegetation damage, and behavioral changes in aquatic organisms. Studies have shown that these impacts are concentrated around salt storage facilities. As a result, the United States Environmental Protection Agency issued many state departments of transportation municipal separate storm sewer system (MS4) permits. In Utah, road salt is stored at Utah Department of Transportation (UDOT) maintenance stations, which are regulated by a Phase I MS4 permit. To comply with their MS4 permit, UDOT constructed retention ponds to capture salt-laden stormwater and truck wash water. However, without information and established maintenance and management plans informing pond design, these retention ponds suffer from design issues such as overflow throughout the winter season. Through pollution prevention assessments, pond and tap water analysis, pond sediment analysis, and surface water quality modeling at 11 UDOT maintenance stations, this project provides UDOT with site design guidelines and best management practices to ultimately reduce the impact of UDOT road salt facilities on the environment.

Deep-sea anoxic brine pools are one of the most extreme ecosystems on Earth, which are characterized by drastic changes in salinity, temperature, and oxygen concentration. The interface between the brine and overlaying seawater represents a boundary of oxic-anoxic layer and a steep gradient of redox potential that would initiate favorable conditions for divergent metabolic activities, mainly methanogenesis and sulfate reduction. This study aimed to investigate the diversity of Bacteria, particularly sulfate-reducing communities, and their ecological roles in the interfaces of five geochemically distinct brine pools in the Red Sea. Performing a comprehensive study would enable us to understand the significant role of the microbial groups in local geochemical cycles. Therefore, we combined culture-dependent approach and molecular methods, such as 454 pyrosequencing of 16S rRNA gene, phylogenetic analysis of functional marker gene encoding for the alpha subunits of dissimilatory sulfite reductase (dsrA), and single-cell genomic analysis to address these issues. Community analysis based on 16S rRNA gene sequences demonstrated high bacterial diversity and domination of Bacteria over Archaea in most locations. In the hot and multilayered Atlantis II Deep, the bacterial communities were stratified and hardly overlapped. Meanwhile in the colder brine pools, sulfatereducing Deltaproteobacteria were the most prominent bacterial groups inhabiting the interfaces. Corresponding to the bacterial community profile, the analysis of dsrA gene sequences revealed collectively high diversity of sulfate-reducing communities. Desulfatiglans-like dsrA was the prevalent group and conserved across the Red Sea brine pools. In addition to the molecular studies, more than thirty bacterial strains were successfully isolated and remarkably were found to be cytotoxic against the cancer cell lines. However, none of them were sulfate reducers. Thus, a single-cell genomic analysis was used to study the metabolism of uncultured phyla without having them in culture. We analysed ten single-cell amplified genomes (SAGs) of the uncultivated euryarchaeal Marine Benthic Group E (MBGE), which contain a key enzyme for sulfate reduction. The results showed the possibility of MBGE to grow autotrophically only with carbon dioxide and hydrogen. In the absence of adenosine 5’-phosphosulfate reductase, we hypothesized that MBGE perform sulfite reduction rather than sulfate reduction to conserve energy.