Faculty of Applied Sciences
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Item Bioaugmentation efficiency of diesel degradation by Bacillus pumilus JLB and Acinetobacter calcoaceticus LT1 in contaminated soils(2010-10-11) Pillay, Charlene; Lin, JohnsonThe abilities of diesel-degrading Bacillus pumilus JLB and Acinetobacter calcoaceticus LT1 were tested in contaminated soils. The effect of nutrient supplementation on bioaugmented samples was also examined. The results show that bio-augmentation and biostimulation accelerated significantly (p < 0.05) the diesel degradation in the contaminated loam soil and sea sand. Supplementing fertilizers to the augmented loam samples did not result in a significantly higher degradation rate. Furthermore, A. calcoaceticus LT1 alone failed to stimulate higher degradation rates in sea sand unless further supplementation of fertilizer. The results from environmental scanning electron microscopy demonstrate the population increases, then decreases in augmented samples corresponding to the level of diesel degradation. Fungi-like microorganisms became dominant in contaminated loam soil at the end of the study but not in sea sand. The study shows that it is critical not only to understand the physiology of the inoculum but also how it affects microbial community structure and function before the microorganism being introduced in the contaminated soil.Item Characterisation and application of bambara protein-polysaccharide complex coacervates in encapsulation of bioactive compounds(2019) Busu, Nyasha M.; Amonsou, Eric OscarBambara groundnut (Vigna subterranea) is a leguminous crop that is indigenous to Africa. In South Africa, the legume is cultivated in KZN, Limpopo and Mpumalanga where it is considered a traditional food. Bambara groundnut is a good source of protein (15 – 28 %) and contains substantial amounts of starch. The legume thrives well in areas of low agricultural input. Despite its good protein content, bambara groundnut is mostly cultivated in rural areas for by subsistence farmers. In recent years, there has been increased interest in bambara groundnut protein as an alternative protein source. The purpose of this study is to investigate the complexation behavior of bambara protein with gum Arabic and test the application of the formed complexes in encapsulation and delivery of bioactive compounds. In the first part of this study, four protein fractions extracted at different pH including the salt-solubilisation method were complexed with gum Arabic. The protein content as well as physicochemical properties (SDS-PAGE, FTIR, Zeta potential, SEM) of the protein fractions and resulting bambara protein-gum Arabic (BPI-GA) complexes were then investigated. In subsequent parts of the study, bambara protein extracted by the salt-solubilisation method was complexed with gum Arabic. The influence of ionic strength and biopolymer mixing ratio on complex formation was investigated. Subsequently, the emulsification properties, foaming properties, encapsulation efficiency and release properties of the formed complexes were also investigated under simulated gastric and intestinal pH conditions. The salt-soluble fraction showed the highest protein content (82%) whilst the lowest protein content (76%) was recorded at pH 2. The FTIR analyses revealed an increase in β-sheet content with decrease in pH of extraction. Complexation of the protein fractions with GA resulted in the optimal pHs of interaction shifting towards acidic regions (pHopt: 4.8 to 2.9) as pH of protein extraction became more acidic. Upon complexation, protein fractions produced coacervate yields ranging between 41 - 68%, with the pH 2 fraction recording the lowest (41%) yield. Further, addition of gum arabic seemed to broaden the turbidity profiles. When assessed by SEM, the particles appeared as spherical and aggregated structures between 100-200 nm.Item Characterisation of Opuntia phenolic extracts and enzymatic modification of selected compunds(2019) Aruwa, Christiana Eleojo; Kudanga, Tukayi; Amoo, Stephen O.Opuntia species are utilised as local medicinal interventions for chronic diseases and as food sources. The phytochemical profile varies within and across Opuntia species and has been related to differences in cultivar and geographical location. Macromolecular antioxidant (MA) fractions are also largely ignored from most conventional extractive processes compared to the well-known extractable polyphenol fractions. This study characterised subtropical spineless cladode, fruit pulp and peel extracts and selected phenolic compounds for enzymatic modification using a laccase from Trametes pubescens. MA extracts were also characterised in comparison with extractable fractions. The effects of drying methods and extraction solvent on extract yields and bioactivities were also studied. Extracts were assayed for phenolic content and antioxidant activities were determined using standard 2,2’-diphenyl-1-picrylhydrazyl (DPPH), 2,2,-azinobis3-ethylbenzthiazoline-6-sulfonic acid (ABTS) and ferric reducing antioxidant power (FRAP) assays. Antimicrobial activities and mode of antibacterial action were assessed against type-bacterial cultures. Minimum inhibitory concentration (MIC) values were recorded for the extracts and compounds. Compound profiling was achieved using liquid chromatography-time of flight-mass spectrometry (LC-TOF/MS) in negative ionisation mode. Antibacterial and antioxidant activities were higher in MA, hydrolysed and hydroalcoholic cladode and fruit extracts than in aqueous fractions. Ethanolic, methanolic and hexane extracts of freeze-dried Opuntia cladode, MA and peel samples showed higher total phenolic content, and in vitro antioxidant and antimicrobial activities than the oven-dried extracts. Cladode extracts inhibited growth of both Gram-positive and Gram-negative microorganisms (MIC range of 25 to 250 mg/mL). Likewise, fruit extracts inhibited both Gram-positive and Gram- negative microorganisms (MIC range of 2.5 to 18.75 mg/mL). Cladode and fruit extract profiles showed the presence of mainly phenolic acids and flavonoid derivatives. Isovitexin 7-O- xyloside-2"-O-glucoside, polyhydroxypregnane glycoside and neohancoside C in Opuntia cladode, and pinellic acid in Opuntia fruit were identified for the first time in this study. Some compounds, however, remained unidentified. Thereafter, selected Opuntia cladode and fruit phenolic compounds (isorhamnetin and luteolin) were used for enzymatic (laccase) transformation after preliminary screening reactions. Laccase-catalysed oxidation of luteolin in a monophasic system containing sodium acetate buffer (pH 5.0) and ethanol (50%, v/v) as co- solvent, resulted in the production of a dimer (m/z 569, M=570). Using a similar approach, oxidative coupling of isorhamnetin produced two main products, IP1 which was a dimer (m/z 629, M=630) and IP2 (m/z 457, M=458) which was most likely a result of coupling of an oxidative cleavage product and the isorhamnetin monomer. Dimers showed up to two-fold improvement in antioxidant and antimicrobial activities, compared to their respective substrates. The synthesised products showed a bactericidal mode of action as demonstrated by time-kill and bacterial cell integrity assays. The bactericidal action was further confirmed by scanning electron microscopy (SEM) which showed that treatment of bacterial cells with the synthesised compounds resulted in deformed, pitted, broken or fragmented cells, indicating strong bactericidal action. In conclusion, this study showed that Opuntia fruit pulp, peel and cladode extractable and MA extracts have potential as sources of phenolic compounds with antioxidant and antimicrobial activities. Laccase catalysis has potential to transform the phenolic compounds into coupling products with higher biological activities. The synthesised products have potential for application in the food, nutraceutical and other relevant industries.Item Occurrence of vancomycin resistant enterococci (VRE) in two Durban wastewater treatment plants for effluent reuse(2019) Madu, Chibuzor Ezinne; Stenström, Thor-Axel; Reddy, Poovendhree; Adegoke, Anthony AyodejiThe presence of enterococci in improperly treated wastewater leads to pollution of the recipient water bodies which directly or indirectly affects the humans especially when antibiotic resistant strains are involved. In 2017 the World Health Organization listed vancomycin resistant enterococci (VRE) among those with highest priority for further surveillance and research, both among humans and in the receiving aquatic environment. The purpose of this study is to determine how efficient the WWTPs are in removing both vancomycin-resistant enterococci (VRE) and vancomycin-sensitive enterococci (VSE) from wastewater. One hundred (60 wastewater and 40 river) samples were collected from July 2016 to June 2017 which covered the warm and cold seasons of South Africa. Primary isolation and enumeration were carried out on Slanetz and Bartley agar supplemented with and without vancomycin (6 µg/mL) for vancomycin resistant enterococci (VRE) and total enterococci (TE) respectively. Presumptive enterococci were selected using Gram staining, growth on bile aesculin agar, catalase and pyrase tests. The presumptive enterococci isolates (202 VRE and 67 VSE) were confirmed and speciated using polymerase chain reaction (PCR). The identified Enterococcus isolates were subjected to antibiotic susceptibility testing (AST) to examine their resistance profile against fifteen antibiotics including vancomycin. Antibiotic resistance genes (van, tet and emeA) were detected by PCR. The TE and VRE counts of the two WWTPs influents ranged from 6.1 to 7.2 log10 CFU/100 mL (for TE) and 4.3 to 6.7 log10 CFU/100 mL (for VRE) while the effluent concentration of Plant II contained 1.5 to 4.4 log10 CFU/100 mL and 0.9 to 3.4 log10 CFU/100 mL for TE and VRE respectively. Neither TE nor VRE was detected in Plant I effluent. The TE and VRE counts of the recipient river samples were higher than the effluents. There were no visible seasonal effects based on the counts. The removal efficiencies in the two plants ranged from 95 to 100%, where chlorination played a major role. Two hundred and sixty- nine (202 VRE and 67 VSE) isolates were identified by PCR as Enterococcus. The most abundant species was E. faecium followed by E. faecalis while other species include E. hirae, E. gallinarum, E. durans, E. casseliflavus and E. cecorium. MALDI-TOF and PCR were used in parallel for the identification of the isolates, which resulted in 80.1% agreement for genus identification. The AST results showed that a large percentage (39 to 98%) were resistantto all other antibiotics except amoxicillin/clavulanic acid and imipenem to which the isolates showed high sensitivity. Four van genes (vanA, vanB, vanC1, vanC2/3) and 4 tet genes (tetK, tetL, tetM, tetO), and also the multidrug efflux pump gene, emeA were detected among the 269 enterococci isolates with vanA and tetL being the most prevalent. At least one virulence gene (ace, asa1, cylA, efaA, esp, gelE and hyl) occurred in 74% (67/88) of the isolates. The result showed that the two WWTPs are efficient in removing both enterococci and VRE from their influents. Thus these effluents had little or no effect to enterococci count of their interlinked recipients. Also, a majority of the isolates are not only antibiotic resistant strains but are also virulent. They therefore pose risk to public health.Item Utilization of shrimp waste for the recovery of valuable bioactive compounds(2018) Dlamini, Nosihle; Permaul, KugenShrimp waste is a major by-product of crustacean processing and represents an interesting source of bioactive molecules. In addition, its use increases the sustainability of processing fishery products. The present study reports a process developed for recovering bioactive molecules from shrimp waste through the use of chemical methods. The samples of shrimp were confirmed to be from the species Haliporoides triarthrus. The recovery of chitin was 30% of the processing waste and 30-60% chitosan (CH) from chitin. CH was characterized by FTIR analysis and exhibited a degree of deacetylation (DDA) of 72%. From the demineralization extract, CaCO3 was extracted and confirmed by FTIR. Based on a kinetic study of acid hydrolysis, it was demonstrated that chitin can be quantitatively hydrolysed into glucosamine (GlN), N-acetyl glucosamine (GlcNAc) and their respective oligomers with 32% hydrochloric acid at 60oC and qualitatively from CH with 32% hydrochloric acid at 80oC. The oligomer mixed fractions were desalted by activated charcoal extraction and the components of each fraction were analysed by TLC and HPLC. Chitooligosaccharides (COS) and N-acetly chitooligosaccharides (NAcCOS) with degrees of polymerization (DP) ranging from 2 to 6 were obtained from CH and chitin, respectively. The antimicrobial activities of chitosan, COS and NAcCOS were investigated against five gram-negative bacteria and five gram-positive bacteria. Chitosan exhibited stronger bacteriostatic effects against gram- positive bacteria than gram-negative bacteria in the presence of 1% chitosan. The oligomers showed no bacteriostatic or bactericidal effects on all tested bacteria. A total 30.74± 0.078 µg.g-1 astaxanthin was extracted with 90% acetone from the species; Haliporoides triarthrus and TLC analysis indicated that the species contained both astaxanthin and its esters. Chitosan films were obtained by solution casting of blends of chitosan with glycerol, polyethylene glycol 200 (PEG-200) and polyethylene glycol 600 (PEG-600) as plasticizers. Films were characterized by FTIR, XRD diffraction, TGA, and SEM analysis. The tensile strength and elongation at break properties of the films were also evaluated. CH films and CH/GLY blended films were translucent in appearance and the CH/PEG 200 and CH/PEG 600 films were opaque. The CH films yielded mechanically resistant films without the use of a plasticizer. These data point to the feasibility of an integrated process for isolating highly bioactive molecules, such as oligosaccharides, with a broad spectrum of applications from shrimp processing waste.Item Anti-inflammatory, anti-oxidant and wound-healing properties of selected South Africa medicinal plants(2017) Mzindle, Nonkululeko Betty; Odhav, BhartiSouth Africa has a wide range of medicinal plants that are used traditionally by black Zulu South Africans for the treatment of a range of illnesses, including inflammatory ailments; disease conditions caused by oxidative stress and wound healing. It has been indicated that bioactive compounds isolated from plants contribute to their anti-inflammatory, antioxidant and wound healing properties; hence, herbal remedies have been widely used traditionally in many countries in the management and treatment of wounds. Inflammation is the main condition that relates to a variety of diseases affecting most of the world’s population. It is the body’s immune response to infection and injury and is induced by the release of pro-inflammatory mediator’s —prostaglandins and leukotrienes—following wound occurrence. Wounds result in disruption of living tissue caused by oxidative stress. Anti-inflammatory agents, antioxidants, and antimicrobials play an important role in the wound healing process and they prevent aggravated wound conditions.Controlling inflammation during wound repair is important to minimize any additional complications that may result; hence, chemical agents such as non-steroidal anti-inflammatory drugs (NSAIDS), synthetic antioxidantsand steroids are frequently used. These drugs block the enzymes that are responsible for prostaglandin synthesis in inflammation, react with free radicals thereby interfering with oxidation process as a result affect one or more phases of wound healing. The use of these drugs, however, has been limited as they can cause detrimental side effects when used over long periods of time.There is, consequently, a need to find alternative natural therapeutic drugs. Studies on medicinal plants confirmed that herbal drugs exhibit fewer side effects in comparison with chemical agents and are more cost-effective.Thus the aim of this study was to investigate South African medicinal plants, for anti-inflammatory, antioxidant and wound healing properties. Dissolved extracts of thirty-eight medicinal plants were evaluated for theiranti-inflammatory activity using the 5-lipoxygenase assay as well as free radical scavenging activity using the 1; 1-diphenyl-2-picrylhydrazyl (DPPH) assay.Their safety was evaluated using brine shrimp lethality assay. Proliferation and viability of fibroblast cells was determined by the3-(4, 5-dimethylthiazolyl)-2, 5-diphenyltetrazolium bromide(MTT) assay furthermore a scratch wound assay was used to study the properties of wound healing in vitro and to confirm the anti-inflammatory activities of the dissolved extracts. Migration rate was evaluated quantitatively by an image analyzer. Methanol was chosen for extraction because it completely dissolves extracts. Anova was used for statistical analysis. Almost all aqueous extracts were found to be effective in inhibiting lipoxygenase enzyme when compared to nordihydroguaiaretic acid (NDGA). Aqueous extracts exhibited remarkably high percentage inhibition of lipoxygenase with most above 100% when compared to methanolic extracts. Amaranthus dubius and Portulaca oleracea were found to have good biological activities in the inhibition of 5-lipoxygenase enzymes when compared to the other plants. However, Galinsoga parviflora and Syzygium cordatumwere least effective in inhibiting enzyme activity with percentages as low as -2% and 34% respectively. Percentage inhibitions for methanolic extracts were lower than that of aqueous extracts. Amaranthus spinosus had the highest percentage inhibition among all the methanolic extracts andGalinsoga parviflorahad the lowest. The methanolic plant extracts were found to be more effective in scavenging DPPH free radicals than the corresponding aqueous extracts. All the methanolic extracts exhibited free radical scavenging ability in the range of 60%–104%. Asystasia gangetica, Ficus sur, Heteropyxis natalensis, Hibiscus sabdariffa, Pelargonium sp. showed notably higher scavenging abilities, ranging from 101%–104% compared to Rutin. Methanolic extracts of Heteropyxis natalensis and Hibiscus sabdariffa exhibited scavenging ability even at the lowest concentration of 10μg/ml. Furthermore, aqueous extracts displayed remarkably lower activities than methanolic extracts with thirty-one extracts having a scavenging capacity ranging from 22%—59%. None of the extracts were found to be detrimental to brine shrimp. Almost all the extracts were shown to stimulate the growth of fibroblast cells except the methanolic extract of Solanum nodiflorum, which was shown to be killing the cells at high concentrations with a percentage viability of 46%.As the concentration decreased, however, the viability of cells with this extract increased to 143%. An increase in the number of fibroblast cells was observed in the scratched area of the treated cells and a significant migration rate was also noted with some of the extracts. Aqueous extracts of Sonchus oleraceus (86%), Justicia flava (85%) and Dichrostachys cinerea (85%) and methanolic extracts of Senna occidentalis and Hibiscus sabdariffa were found to have the highest migration rate compared to untreated cells that served as a control. No cell migration was observed with methanolic extract of Solanum nodiflorum.Instead, the extract was found to be toxic to the cells. Some of the plants evaluated in this study have been studied for either anti-inflammatory, antioxidantand wound healing properties in vivo, however, no work has been conducted to demonstrate a correlation between anti-inflammatory, antioxidant and wound healing properties of plant species in vitro. The current study was, therefore, conducted to review medicinal herbs considered as anti-inflammatory, antioxidants and wound healing agents as well as collecting evidence for their effectiveness and pharmacological mechanisms in modern science. In the plant species investigated Amaranthus dubius, Asystasia gangetica, Bidens pilosa, Buddleja saligna, Carpobrotus dimidiatus, Chenopodium album, Dichrostachys cinerea, Emex australis, Ficus sur, Guilleminea densa, Hibiscus sabdariffa, Physalis viscose, Syzygium cordatum, Taraxacum officinale and Tulbaghia violacea demonstrated good anti-inflammatory and wound healing properties.In conclusion the results from this study demonstrated promising anti-inflammatory and antioxidantactivities as well as wound healing properties,furthermoreit was aslo shown that the plant extracts were not toxic to the cells hencethis suggested that the plants investigated, can be used as substitutes or to formulate wound healing agents that are safe to use in primary healthcare.Item Assessment of a biological nutrient removal process for the remediation of edible oil effluent(2002-05-10) Mkhize, Sandile Psychology; Bux, FaizalEutrophication is a natural process that is greatly aggravated by the action of man in the natural environment. Deterioration of South Africa's natural water resources results directly or indirectly from the discharge of industrial effluent rich in nutrient nitrogen and phosphorus. The South African edible oil refmeries generally discharge poor quality effluent which impacts negatively on the water resources and wastewater treatment installations. The main aim of this study was to assess the capacity of a laboratory scale effluent treatment process that will produce final effluent of acceptable quality with regards to organic load and phosphate concentration prior to its discharge into the municipal sewerage system. The study was conducted in three stages: wastewater characterization, treatability studies, and laboratory scale treatment investigations. After analysing various effluent parameters, treatability studies were conducted using an aerobic-anaerobic sequencing batch reactor with a total hydraulic retention time of 24 hours. The results showed an average of 75 % reduction of COD and more than 90 % removal of fats, oils and grease (FOG). Based on the results of effluent characterisation and treatability studies, a laboratory scale activated sludge effluent treatment process was designed and operated with two bioreactors (aerobic and anaerobic) in series. The system was operated for a period of one-month resulting in 70 % removal of COD and 4% reduction in phosphate (P04-P). After some structural and operational changes from the original design configuration, the system was the operated continuously for the duration of the study period. An optimum COD removal of 75 % and 107 mgll P04-P reduction was achieved during the last operational phase of the system. More than 95 % reduction in fats, oils and grease (FOG) had been achieved in both semi-continuously and continuously operated systems.b.7Item The use of PAM fluorometry to assess microalgal physiological stress for the production of biodiesel(2011) White, Sarah Anne; Bux, FaizalUnder environmental stress, most microalgae produce intracellular neutral lipids as a storage mechanism. In the biotechnology industry, these lipids are extracted and converted to microalgal biodiesel; however the extent of the stress is not measured for optimum lipid accumulation. In the series of studies undertaken, Pulse Amplitude Modulated (PAM) fluorometry was used to measure three types of physiological stress on Chlorella sp., a freshwater microalgal species. Biomass and lipid yields were also used as indicators of the induced stress conditions. Firstly, nutrient induced physiological stress and the subsequent synthesis of cellular neutral lipids was investigated.Item Mitigation of carbon dioxide from synthetic flue gas using indigenous microalgae(2017) Bhola, Virthie Kemraj; Bux, Faizal; Swalaha, Feroz MahomedFossil carbon dioxide emissions can be biologically fixed which could lead to the development of technologies that are both economically and environmentally friendly. Carbon dioxide, which is the basis for the formation of complex sugars by green plants and microalgae through photosynthesis, has been shown to significantly increase the growth rates of certain microalgal species. Microalgae possess a greater capacity to fix CO2 compared to terrestrial plants. Selection of appropriate microalgal strains is based on the CO2 fixation and tolerance capability, both of which are a function of biomass productivity. Microalgal biomass could thus represent a natural sink for carbon. Furthermore, such systems could minimise capital and operating costs, complexity, and energy required to transport CO2 to other places. Prior to the development of an effective CO2 mitigation process, an essential step should be to identify the most CO2-tolerant indigenous strains. The first phase of this study therefore focused on the isolation, identification and screening of carboxyphilic microalgal strains (indigenous to the KwaZulu-Natal province in South Africa). In order to identify a high carbon-sequestering microalgal strain, the physiological effect of different concentrations of carbon sources on microalgae growth was investigated. Five indigenous strains (I-1, I-2, I-3, I-4 and I-5) and a reference strain (I-0: Coccolithus pelagicus 913/3) were subjected to CO2 concentrations of 0.03 - 15% and NaHCO3 of 0.05 - 2 g/1. The logistic model was applied for data fitting, as well as for estimation of the maximum growth rate (µmax) and the biomass carrying capacity (Bmax). Amongst the five indigenous strains, I-3 was similar to the reference strain with regards to biomass production values. The Bmax of I-3 significantly increased from 0.214 to 0.828 g/l when the CO2 concentration was increased from 0.03 to 15% (r = 0.955, p = 0.012). Additionally, the Bmax of I-3 increased with increasing NaHCO3 concentrations (r = 0.885, p = 0.046) and was recorded at 0.153 g/l (at 0.05 g/l) and 0.774 g/l (at 2 g/l). Relative electron transport rate (rETR) and maximum quantum yield (Fv/Fm) were also applied to assess the impact of elevated carbon sources on the microalgal cells at the physiological level. Isolate I-3 displayed the highest rETR confirming its tolerance to higher quantities of carbon. Additionally, the decline in Fv/Fm with increasing carbon was similar for strains I-3 and the reference strain (I-0). Based on partial 28S ribosomal DNA gene sequencing, strain I-3 was found to be homologous to the ribosomal genes of Chlorella sp. The influence of abiotic parameters (light intensity and light:dark cycles) and varying nutrient concentrations on the growth of the highly CO2 tolerant Chlorella sp. was thereafter investigated. It was found that an increase in light intensity from 40 to 175 umol m2 s-1 resulted in an enhancement of Bmax from 0.594 to 1.762 g/l, respectively (r = 0.9921, p = 0.0079). Furthermore, the highest Bmax of 2.514 g/l was detected at a light:dark cycle of 16:8. Media components were optimised using fractional factorial experiments which eventually culminated in a central composite optimisation experiment. An eight-factor resolution IV fractional factorial had a biomass production of 2.99 g/l. The largest positive responses (favourable effects on biomass production) were observed for individual factors X2 (NaNO3), X3 (NaH2PO4) and X6 (Fe-EDTA). Thereafter, a three-factor (NaNO3, NaH2PO4 and Fe-EDTA) central composite experimental design predicted a maximum biomass production of 3.051 g/l, which was 134.65% higher when compared to cultivation using the original ASW medium (1.290 g/l). A pilot scale flat panel photobioreactor was designed and constructed to demonstrate the process viability of utilising a synthetic flue gas mixture for the growth of microalgae. The novelty of this aspect of the study lies in the fact that a very high CO2 concentration (30%) formed part of the synthetic flue gas mixture. Overall, results demonstrated that the Chlorella sp. was able to grow well in a closed flat panel reactor under conditions of flue gas aeration. Biomass yield, however, was greatly dependent on culture conditions and the mode of flue gas supply. In comparison to the other batch runs, run B yielded the highest biomass value (3.415 g/l) and CO2 uptake rate (0.7971 g/day). During this run, not only was the Chlorella strain grown under optimised nutrient and environmental conditions, but the culture was also intermittently exposed to the flue gas mixture. Results from this study demonstrate that flue gas from industrial sources could be directly introduced to the indigenous Chlorella strain to potentially produce algal biomass while efficiently capturing and utilising CO2 from the flue gas.Item Active targeting of cancer cells using gemcitabine conjugated platinum nanoparticles(2017) Odayar, Kriya; Odhav, Bharti; Mohanlall, VireshNanotechnology is explained as the science of engineered materials and systems on a molecular scale. This innovation is currently used in a wide variety of applications which include using these nanoparticles as drug delivery vehicles. Such nanocarriers are relatively smaller than 100 nm in size with the ability to convey therapeutic drugs to a number of disease sites. Platinum-based nanoparticles have been extensively used in a number of applications namely catalysts, gas sensors, glucose sensors and cancer therapy. The properties of platinum nanoparticles (PtNP’s) typically depend on characteristics such as shape, particle size, elemental composition and structure, all of which can be manipulated and controlled in the fabrication process. Their unique size in the nanometer scale makes platinum nanoparticles an ideal candidate as targeted drug delivery vehicles. To target an anticancer drug to a diseased site is a distinctive feature of most studies, which aim to transfer an adequate dosage of the drug to cancer cells. Transport systems used as carriers of anticancer drugs offer numerous advantages, which include improved efficacy and a decrease in toxicity towards healthy cells when compared to standard drugs. The aim of this study was to determine the effect of platinum nanoparticles, gemcitabine and gemcitabine conjugated platinum nanoparticles (Hybrids) against cancer cells and healthy cells and to determine the mode of cell death and cell death pathways using flow cytometry. Platinum nanoparticles were synthesized via the reduction of hexachloroplatinic acid using sodium borohydride in the presence of capping agents. Synthesized platinum nanoparticles and the hybrids were characterized by observing peaks at 301 nm and 379 nm respectively using UV-visible spectroscopy. TEM images revealed that the PtNP’s and the conjugate compounds were spherical in shape with core sizes of 1.14 nm - 1.65 nm and 1.53 - 2.66 nm respectively. The bioactivity platinum nanoparticles, gemcitabine and the hybrids were investigated using MCF7 and Melanoma cancer cells at different concentrations from 0.10 to 100 µg/ml. Results indicated that conjugated nanoparticles induced the highest cell inhibition against both cell lines compared to gemcitabine and platinum nanoparticles. Bioactivity against PBMC (peripheral blood mononuclear) cells indicated that all three compounds show little or no effect towards the healthy cell line compared to the control. Melanoma cell line was used to determine the mode of cell death. Apoptosis was detected using Annexin V-FITC to detect membrane changes, JC-1 to detect a loss in mitochondrial membrane potential and caspase-3 assay kits. Results indicated that a significant amount of cell death was caused by cleavage of caspase-3. Nanoparticle drug delivery is an area that has shown significant promise in cancer treatment. Interaction of nanoparticles with human cells is an interesting topic for understanding toxicity and developing potential drug candidates. Imagine, something that is atleast or more than 80,000 times smaller than the edge of the ridge on a fingertip and unlocks a new wilderness into cancer research. Nanotechnology, known as the science of minute, is changing the approach to cancer and especially future diagnosis and treatment. Nanotechnology permits scientists to fabricate new apparatuses that are definitely smaller than cells, giving them the chance to attack tumor diseased cells. This innovation not just empowers practitioners to recognize malignancies prior but additionally holds the guarantee of halting cancer growth before it further develops. This progressive approach is so exact, specialists will in future be able to outline a unique treatment for an individual’s own restorative and hereditary profile. Researchers are designing nanoparticles that detect and destroy diseased cells and this optimistic innovation could be personalized for targeted drug delivery, enhanced imaging and ongoing affirmation of cancer cell death. The National Cancer Institute remains hopeful that facilitated development, nanotechnology will drastically change cancer treatment.