Research Publications (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 Biosynthesis and characterization methods of copper nanoparticles and their applications in the agricultural sector(Elsevier, 2022-01-15) Reddy, Bhagavanth; Mangatayaru, Girija K.; D, Madhusudan Reddy; Krishna, Suresh Babu Naidu; Golla, Narasimha; Kamel A, Abd-ElsalamThis book provides information on the design and application of ecologically safe formulations, for protecting cultivated crops against insects and pathogen-causing diseases, plant science, antimicrobial applications and agroecosystem ...Item Determining nutritional status and food intake patterns of pre-school children in Empangeni, South Africa(AJHTL, 2016) Mwadiwa, R.J.; Kearney, J.E.; Napier, Carin E.The major goal of the assessment was to establish the prevalence of child malnutrition in two sampled pre-schools, in order to determine the resources and approaches required for an appropriate response to the concern, and with a view to finding sustainable solutions. The means of anthropometric measurement tools concurrently with socio-demographic and food frequency questionnaires were applied in conducting the survey to evaluate the food intake patterns of the 1-3 year old pre-school children. The cross-examination of the pre-school cycle menus was analysed. The combined results of the tools applied in data collection were also used to classify nutrient deficiencies of the sample group as well as detecting specific dietary requirements comparing with the World Health Organisation’s standards. The findings of the assessment showed that malnutrition was prevalent among the 1-3 year olds in the sampled pre-schools and that these conditions resulted from persistent household and pre-school food insecurity in quantity, quality and diversity. The food intake patterns were inconsistent as in some instances children consumed either high or low intakes of macro or micro nutrients and that consumption habits were incompatible with required nutrient RDAs per child. The ultimate objective of the assessment was to form the core for implementing a more in-depth experimental study aimed at scientifically developing novel food products out of integrating traditional and modern processed foods. The researcher’s primary objective is to improve the pre-school feeding menus in the hope of adding value to the nutritional status of the target population.Item Development of an energy-dense biscuit suitable for primary school learners for the South African National School Nutrition Programme(African Journal of Food, Agriculture, Nutrition and Development, 2021) Hassanally, Saffia; Naicker, Ashika; Singh, EvonneSouth Africa has a well established National School Nutrition Programme (NSNP). Despite rescheduling the mealtime to two hours after the start of the school day to accommodate learners who come to school on an empty stomach, a gap still exists as many children start their learning day with low energy and concentration levels. A cost-effective, energy-dense snack served at the start of the school day can be a solution to sustain learners until the main meal is served. Cross-sectional surveys were used to determine the snack preferences of children and the product development process was used to develop a suitable snack. An energy-dense peanut butter biscuit was developed based on those surveys as well as a scoping review of previous snack studies. The energy-dense developed product provided 1388kJ (61.0%) of energy from fat, 688kJ (30.2%) of energy from carbohydrates and 201kJ (8.8%) of energy from protein per 100g. The biscuit conformed to microbial testing standards. Shelf-life analysis projected a shelf-life of five weeks fresh and five months in food grade packaging. Sensory results showed that there was no significant difference in sensory scores across gender (p=0.691) and age (p=0.706). More of the learners (n=56, 69.1%) found the biscuit to be ‘Super good’ than the other ratings (p<.0005). When compared with similar biscuit products currently on the market, it was found that the developed biscuit was the most reasonably priced. The developed biscuit has the potential to serve as a solution to hidden hunger for children that come to school on an empty stomach. This versatile snack solution has potential for continuity of use even during periods of national crisis as with COVID-19, when learners’ nutritional needs may be most vulnerable.Item Irrigation water and microbiological safety of fresh produce : South Africa as a case study : a review(Academic Journals, 2012-09-11) Ijabadeniyi, Oluwatosin Ademola; Buys, E. M.Irrigation water is perhaps the leading pre-harvest source of contamination of fresh produce in the world. In this review, the impact of contaminated surface irrigation water on bacterial contamination of fresh produce was examined. Some practical solutions to prevent or reduce this challenge were also considered. In South Africa, fruit and vegetables are produced on a large scale by commercial farmers who depend on surface water for their cultivation. However, the surface water, that is, rivers- has been reported to be heavily contaminated with Escherichia coli and feacal coliforms. There is a concern that contaminated surface water used for irrigation may contaminate fresh vegetables which may also have a negative effect on the export of vegetables to the EU and USA. Consumption of vegetables contaminated with foodborne pathogens presents a public health risk especially in countries like South Africa that has more than 5 million people with immune-system compromised diseases such as HIV and tuberculosis. Other groups of people that may be negatively affected because of the contaminated surface water are those who are directly and indirectly associated with the production of fresh vegetables such as pickers, handlers, packers and farmers that participate in the production of vegetables during pre-harvest and post-harvest. Prevention of contamination of fresh produce from both pre-harvest and post-harvest sources especially irrigation water still remains the only effective way to protect the public. However, for this to occur, every stakeholder in the production industry must have a culture of food safety.Item Nutritional variability in 42 cultivars of spineless cactus pear cladodes for crop improvement(Elsevier BV, 2021-11) Mabotja, M. B.; Gerrano, A. S.; Venter, S. L.; du Plooy, C. P.; Kudanga, T.; Amoo, S. O.In addition to their use in traditional medicine, cactus pear (Opuntia species) are a source of vegetal nutrients in many countries. The aims of this study were to determine variability in the nutritional value of 42 spineless cactus pear cultivars, identify correlations between nutritional traits, and determine superior cultivars based on cladode nutritional value. Cladodes of 42 spineless cactus pear cultivars grown under the same glasshouse conditions were collected from the Roodeplaat research farm of the Agricultural Research Council, South Africa. The sliced, dried and powdered cladodes were subjected to quantitative analysis of their vitamin C, b-carotene and mineral element contents. Significant variations in nutritional values were observed among the different cultivars. Vitamin C content ranged from 8.95 mg/100 g in cultivar Ofer to 124 mg/100 g in cultivar Malta, whilst b-carotene content ranged from 3.9 mg/100 g in cultivar Murado to 31.4 mg/100 g in cultivar Cross X. Potassium and calcium were the most abundant mineral elements present, whilst iron was found to be the least present among the mineral elements quantified. A significant positive association was established between calcium (Ca), potassium (K) and zinc (Zn) contents. A direct selection for increased concentration of Ca could be a selection criterion for the development of population with an indirect improvement of K and Zn concentrations. The observed variations highlight the need for a careful cultivar selection for population and product development using spineless cactus pear cladodesItem Plant cell culture systems for the production of secondary metabolites : a review(International Organization Of Scientific Research (IOSR), 2020-03-09) Mohanlall, VireshPlant cell culture systems represent a potential source of valuable secondary metabolites which can be used as food flavourants, colorants, cosmeceuticals, nutraceuticals and pharmaceuticals. Environmental parameters that effect the cultivation of plants for the production of secondary metabolites include environmental factors, political and labour instabilities in the producing countries, uncontrollable variations in the crop quality, crop adulteration, and losses in post-harvest storage and handling. In most cases, the chemical synthesis of secondary metabolites is either extremely difficult or not economically feasible. The production of useful and valuable secondary metabolites from cell cultures is an attractive alternative to conventional plant cultivation techniques. Cell culture technology was developed as a possible tool to both study and produce plant secondary metabolites. The evolving importance of the secondary metabolites has resulted in a high level of interest in the possibility of altering their production through improving cultivation technology.This review summarizes conventional and alternative plant cell culture techniques for the production of secondary metabolites.Item Product development, nutrient analysis and sensory evaluation of maize chips, enhanced with moringa oliefera(2020-10-14) Naicker, Ashika; Govender, KarinaProduct development of nutritionally enhanced foods, to improve food and nutrition security in developing countries, has gained momentum over the years. This study involved the product development optimization, analysis of nutrient and physiochemical content of a maize chip, enhanced with moringa oliefera, as a nutritious and safe snack for children. Food product development trials, nutritional analysis and microbiological testing were conducted. Two samples of moringa maize chip were developed: sample 1 (1 g moringa / 22 g portion of maize chips) and sample 2 (2 g moringa / 22g portion of maize chips). Samples 1 and 2 contained 1.81 g and 2.27 g of fat, 84.9 μg and 100.2 μg of vitamin A and 220 mg and 273 mg of calcium, respectively. Sensory evaluation of the product developed was conducted through a cross-sectional study. One hundred children, aged 9–13 years from four schools were recruited through stratified random sampling from Verulam, Durban, South Africa. Using a validated five-point facial hedonic scale, sensory evaluation revealed that the chips, containing 2 g moringa, were preferred to those with 1 g moringa, for taste and texture. The promising nutritional analysis results and sensory evaluation outcomes indicated the potential for maize chips containing moringa, to serve as a healthier, sensory acceptable snack suitable for children.Item Safety of nanofood : a review(Academic Journals, 2012-10-30) Ijabadeniyi, Oluwatosin AdemolaIntroduction of genetically modified (GM) foods generated a lot of controversy few years back, now it is the turn of nanofoods. There has been debate on the safety of foods that have been produced directly or indirectly with nanomaterials. Nanoparticles or nanotechnology procedures may be used to make food products, food additives, seeds and food packaging materials to give rise to a new and novel nanofood. While a lot have been written about the benefits of nanotechnology and nanomaterials in the food system, there is little research into the toxicological and possible hazard of nanofood. In this paper, the concept of nanotechnology, its diverse applications in the food industry and recent safety issues are considered. The paper concluded that it is necessary to do a thorough risk assessment of nanofoods before they are released to the market.Item Use of autologous adipose-derived mesenchymal stem cells for ovarian rejuvenation in poor responder IVF patients: a phase 1 randomized placebo-controlled double-blind crossover study(Ovid Technologies (Wolters Kluwer Health), 2023-01) Cassim, Mohamed Iqbal; Mohamed, Tasneem; Adam, Jamila Kathoon; Niesler, Carola; Chikandiwa, AdmireBackground: Despite the application of various methods to augment ovarian responsiveness, the management of poor ovarian responders remains challenging and pregnancy rates following in vitro fertilization are poor. Advances in adult stem cell research and their clinical application has prompted interest in their use in assisted reproduction. We report the first double-blind, randomized, placebo-controlled clinical study using autologous human stromal vascular fraction (SVF) containing adipose-derived stem cells (ADSCs) for ovarian rejuvenation. Materials and methods: Thirty patients were recruited. Twenty-one had lower-than-expected reserves for their age and 9 had premature ovarian insufficiency. Patients were randomized into a placebo group (10) and an intervention group (20). SVF was obtained from adipose tissue following abdominal liposuction; the ADSC component was characterized using flow cytometry. Three equal insertions, adjusted based on ovarian volume, were performed at monthly intervals via an ultrasound-guided transvaginal needle puncture. The SVF was not cultured before transplantation. Those in the placebo group were then crossed over to the intervention group and received a single SVF (maximally concentrated) insertion (crossover group). Results: The median viable SVF cell number inserted per patient over 3 months, and the percentage of mesenchymal stem cells (MSC) thereof, was 1.6 × 10 6 and 13.2%, respectively. Resulting anti-Mullerian hormone (AMH) changes were variable over the treatment course with a notable placebo effect. Patients with premature ovarian insufficiency showed no change in AMH, both to intervention and placebo. Despite this, a temporary return of menses was noted in a third of patients while on treatment. Patients with low reserves for age showed an increase in AMH, although not statistically significant when compared to placebo. In the crossover group, insertions were limited to one intervention comprising all cells; here a significantly higher median of 3.4 × 106 SVF cells were injected containing an average of 16.9% MSCs. No significant change in AMH was noted. To date 12 patients have undergone ovarian stimulation and in vitro fertilization after stem cell therapy; of these 9 have had embryo transfers with a resulting pregnancy rate of 33%. There were also 2 spontaneous pregnancies. Conclusion: Although the application of SVF-derived ADSCs for ovarian rejuvenation remains experimental, the current study provides further support for the safety of this approach and presents encouraging results as to its efficacy in assisted reproduction.