Life and Consumer Sciences / M.A. (Consumer Science)

MSCPNT / Department of Nutrition / Hypertension remains a major public health problem that needs different comprehensive health strategies to deal with it. Indigenous vegetables, Blackjack in particular, have been shown to possess anti-hypertensive properties that are attributed to bioactive chemical substances such as phytochemicals, fiber, antioxidants as well as micronutrients that include potassium, magnesium, calcium, vitamin C, zinc, iron and copper. The use of indigenous vegetables in combination with the conventional hypertension treatment may reduce hypertensive conditions; hence, the purpose of this study was to determine Blackjack nutritional knowledge and consumption by hypertensive patients. A cross-sectional study employing both quantitative and qualitative methods was conducted on 275 hypertensive participants at Mphambo and Mutale Health Centers, Vhembe District of Limpopo Province, South Africa. A questionnaire was used to collect data on participants’ Blackjack nutritional knowledge, Blackjack availability around their households as well as their Blackjack consumption patterns and nutritional status. The Blackjack nutritional knowledge data was triangulated with focus group discussions and participants’ nutritional status was assessed by anthropometric and dietary intake methods. The body mass index (BMI) was calculated and dietary intake frequency from selected foods was determined. Blood pressure was measured using Microlife automatic blood pressure monitor. The findings indicated that most hypertensive participants had poor knowledge of the nutritional importance of Blackjack and its associated medicinal contribution on hypertension management. Participants were unable to mention different diseases that can be prevented or managed by Blackjack, which was mostly consumed once a week with porridge during the summer season. Hypertensive patients were consuming high amounts of sodium and less amounts of minerals that are known to regulate blood pressure, such as potassium and magnesium. Hypertensive patients had high prevalence of overweight and obesity and most were either in hypertension stage 1 or stage 2. Lack of Blackjack nutritional knowledge may have contributed to a decreased consumption of Blackjack by hypertensive patients. The health professionals should promote the nutritional benefits of Blackjack in rural areas, particularly to hypertensive patients to raise awareness of Blackjack’s benefits in disease prevention and management. / NRF

Dietary intake is a strong determinate of the health of an individual. Healthy eating is an important prevention to non-communicable diseases. If behaviour is to be changed insight into what the attitudes and barriers are to eating healthily amongst adolescents is imperative. This can provide knowledge for future prevention campaigns for healthy eating to prevent overweight and obesity. The purpose of the study was to quantitatively describe what attitudes adolescent females have towards healthy eating and what potential barriers omits them from adopting healthy eating behaviours. Data collection was done using structured questionnaires. Girls (N=73) from 3 public all girls’ high schools within Durban, KZN, participated in this study. The findings revealed that overall adolescent girls have a positive attitude to healthy eating. A lack of time, the foods sold in the school shop and the conveniences of less healthy food have been identified as barriers to healthy eating. / Health Studies / M. A. (Public Health)

Baby spinach (Spinacia oleracea L.) is considered to be the one of the extremely nutritious vegetables, rich both in phytochemicals and core nutrients. Nowadays, phytochemicals in plants are raising interest in consumers for their roles in the maintenance of human health. Variation in content of bioactive compounds and core nutrients is the main concern in vegetable production. Factors such as cultural practices specially fertilization, may affect the nutritional and medicinal properties of the plants Therefore, three parallel trials for NPK to investigate the response of baby spinach leaves to nitrogen (N), phosphorus (P) and potassium (K) on chemical composition were conducted, with treatments arranged as follows: 0, 45, 75, 105, 120 kg·ha-1 N and P and 0, 60, 85, 106, 127, 148 kg·ha-1 K in a randomized complete block design (RCBD) with four replications. The results demonstrated that, application of nitrogenous, phosphorus, potassium fertilizers significantly increased the total phenolic content, total antioxidant activity, total flavonoid content and vitamin C while magnesium, iron, zinc and selenium did not exhibit significant response to all treatments applied. The increase in concentrations on total phenolic content, total antioxidant activity, total flavonoid content and vitamin C was observed, reaching maximum at 45 kg·ha-1 N, 75 kg·ha-1 P and 85 kg·ha-1 K. The optimum rates of 45 kg·ha-1 N, 75 kg·ha-1 P, 85 kg·ha−1 K were then used to formulate the NPK treatment combinations as follows: 0, 30: 30: 40, 45:45:60, 60:60:70, 75:75:90 kg·ha-1, arranged in a RCBD with three replicates. The results showed that total phenolic content, total antioxidant activity , total flavonoid content and vitamin C reached maximum in baby spinach leaves at N45:P45:K60 kg·ha-1. / Agriculture and  Animal Health / M. Sc. (Agriculture)

Submitted in fulfillment of the requirements of the Masters of Applied Science in Food and Nutrition, Durban University of Technology, 2015. / AIM: The aim of the study was to identify the need, develop, implement and determine the effect of a Grade R Nutrition Education Programme (NEP) in order to make recommendations to the South African Department of Basic Education (DBE) to include an effective NEP in the pre-primary school education curriculum. OBJECTIVES: The objectives for this study is in two phases, The objective of the baseline study was to assess the need for nutrition education (NE) in Grade R in suburban areas of Durban and identify the most suitable nutrition education tools (NETs) for this age group. For the intervention study the objectives were 1) to develop a nutrition knowledge questionnaire (NKQ) to determine the existing nutrition knowledge of Grade R learners in suburban government and private schools in Durban, 2) to develop a nutrition education programme (NEP) for Grade R based on the South African Food-Based Dietary Guidelines (FBDGs) and the food groups, 3) to implement the NEP in Grade R in a government and private school, 4) to determine the effect of the NEP on the retention of FBDGs (Section one) and food group (Section two) knowledge, and 5) to compare the results between the control group (CG) and the government (EGG) and private (EPG) experimental school groups, and between genders. METHODS: A self-administered nutrition education needs questionnaire was completed by 20 Grade R teachers in Durban suburban schools. Nutrition education material was identified based on the results from the pilot study and a Nutrition education programme developed. The classroom-based intervention study involved 120 Grade R learners in three schools, two experimental schools: government (n=37) and private (n=40), with a control school (n=43), with 35 percent (n= 42) male and 65 percent (n=78) female participants, ranging in age from five to seven years. A validated questionnaire assessed baseline nutrition knowledge of these children. A qualified foundation phase teacher was trained to implement the NEP. The experimental school groups received eight one hour nutrition education (NE) lessons over an eight week period; the control group did not receive any NE. During the lesson firstly theory was covered then the children worked on the related fun activities in the Healthy Eating Activity Book (HEAB) and lastly involved in the nutrition educational games. These included a food group plate puzzles, a NEP board game, a card game and ‘My little story books’. A post-test determined the impact of the intervention. RESULTS: The baseline study confirmed the need for NE in Grade R and identified suitable NETs that were used in the intervention. At pre-test, the nutrition knowledge of Grade R children in the two experimental groups (EG) and one CG was very similar with knowledge of FBDGs greater than knowledge relating to the food groups. Both Grade R EGs showed a significant increase in knowledge for the whole test immediately after the intervention with the CG, achieving similar post-to pre-test results. The intervention had a significant impact on nutrition knowledge of Grade R children in both experimental schools (EGG p=0.004 and EPG p=0.001). The EPG were most knowledgeable regarding FBDGs with no significant difference in knowledge of the EGG. Food group knowledge in all schools was poor at baseline and the NEP resulted in the EGG obtaining the highest post-test results. Post-intervention for the whole test the EGG were marginally (0.80 percent) more knowledgeable than the EPG. The knowledge of boys and girls were very similar in pre-and post-test results. However, the boys were fractionally more knowledgeable than the girls in relation to the whole post-test. In Section two, relating to food group knowledge, girls were slightly more knowledgeable than boys although both genders lacked knowledge in relation to which foods belonged to a particular food group. CONCLUSION: The primary aim of formal NE was met as the statistical significance between the CG and experimental group post-test results was evident in the majority of Section one questions and in all questions in Section two. The NEP resulted in similar increase in knowledge of Grade R learners in the government and private experimental school groups in Durban. In addition, the boys and girls showed a minimal difference in nutrition knowledge.

Text in English / Potato is an important source of energy to most micronutrient malnourished affected population in South Africa. Improvements through bio-fortification can therefore enhance access to essential micronutrients. The study was aimed at determining the level of variability of iron and zinc concentration among 20 potato genotypes as a preliminary step for future breeding program. The materials were evaluated using inductively coupled plasma optical emission spectrometry. Statistical analysis indicated significant (P<0.001) variation of Fe and Zn among the genotypes. The average concentration ranges from 34.67 to 76.67 mg kg-1 and 12.88 to 66.1 mg kg-1 for iron and zinc respectively. The best performing genotypes were cultivar Mnandi, Hertha, Buffelspoort and breeding lines-N105-1, 00-S100-33 and 03-627-50. Iron concentration was positively correlated with Zinc concentration. The study showed that enough variability of Fe and Zn concentration exist among the evaluated genotypes, which can be exploited for use in potato bio-fortification breeding programme. / Agriculture, Animal Health and Human Ecology / M.Sc. (Agriculture)

Text in English / The purpose this study was to explore food habits and nutritional behaviours of adolescents in a school in Lenasia South, in Gauteng Province. Qualitative, explorative research was conducted in order to recommend effective prevention strategies of non-communicable diseases. Adolescents from the selected secondary school formed the sample of the study. Data collection was done using focus groups’ discussions. Three focus group discussions were conducted in the study. The first group comprised of thirteen male adolescents, followed by ten female adolescents and the final group was a combination of both female and male learners to produce a homogenous group. Specific common eating habits and nutritional behaviours emerged from the focus group discussions which included skipping meals, high consumption of high energy dense foods and sweetened beverages. Consequently, when developing intervention programs and policies to improve health of adolescents, environmental influences that undermine efforts to improve adolescent’s dietary behaviours must be addressed. / Health Studies / MPH (Health Studies)

Thesis (PhD(For))--Stellenbosch University, 2012. / The subtropical ecosystem of the Zululand coastal plain is prized by the South African commercial plantation forestry industry for its rapid clonal Eucalyptus growth, short rotations (6 to 7 years) and high yields. This region is typified by sandy soils that are low in clay and organic matter, have small nutrient reserves and are poorly buffered against nutrient loss. The subtropical climate induces rapid decomposition of residues and tree litter resulting in small litter nutrient pools and rapid nutrient release into the soil, particularly after clearfelling. A combination of large nutrient demands through rapid growth, rapid nutrient turnover and small soil nutrient reserves implies that sites in this region are sensitive and may be at risk of nutrient decline under intensive management. The work in this study set out to determine the risk of nutrient depletion through harvesting and residue management on a site within the Zululand region, to assess nutritional sustainability and the risk of yield decline in successive rotations. Some bulk biogeochemical cycling processes of macro-nutrients nitrogen (N), phosphorus (P), potassium (K), calcium (Ca) and magnesium (Mg) were assessed, and assessments also included sodium (Na). An existing Eucalyptus stand was clearfelled and treatments were imposed on the residues after broadcasting to simulate various levels of nutrient loss through levels of harvesting intensity and residue management. These included residue burning (Burn), residue retention (No-Burn), fertilisation (stem wood nutrient replacement), whole tree harvesting and residue doubling. Outer blocks of the stand were not felled, but included as replicates of an undisturbed standing crop treatment. Biogeochemical nutrient cycling processes were assessed primarily in the standing crop, Burn and No-Burn treatments, in the assumption that these represented the furthest extremes of nutrient loss. Data collection commenced a year prior to clearfelling and continued to two years and six months after planting with key data collection over a 20.1 month period from clearfelling to canopy closure (one year after planting). Water related nutrient pools and fluxes were assessed as atmospheric deposition (bulk rainfall, throughfall and stemflow) and gravitational leaching to 1m soil depth. Drainage fluxes were predicted using the Hydrus model and real-time soil moisture data. Zero tension lysimeters collected soil solution for chemical analysis. Sequential coring in the 0 to 30cm soil layer was used to determine in situ soil N mineralisation. Soil chemical and physical properties were assessed over the first meter of soil at clearfelling and new crop canopy closure to determine soil nutrient pools sizes. Biomass nutrient fluxes were assessed from litterfall, residue and litter decomposition, and above ground accretion into the tree biomass. Leaching and N mineralisation were monitored in the No-Burn, Burn and standing crop treatments only. Atmospheric deposition, while variable, was shown to be responsible for large quantities of nutrients added to the Eucalyptus stand. Nitrogen and K additions were relatively high, but within ranges reported in previous studies. Rapid tree canopy expansion and subsequent soil water utilisation in the standing crop permitted little water to drain beyond 1m resulting in small leaching losses despite a sandy well drained soil. Further leaching beyond this depth was unlikely under the conditions during the study period. Mineralisation and immobilisation of N also remained low with net immobilisation occurring. The standing crop was shown to be a relatively stable system that, outside of extreme climatic events, had a relatively balanced or positive nutrient budget (i.e. nutrient inputs minus outputs). Large quantities of nutrients were removed with stem-wood-only harvesting in the No-Burn treatment leaving substantial amounts on the soil surface in the harvest residues. Whole tree removal increased losses of all nutrients resulting in the largest losses of P and base cations compared to all other treatments. This was mostly due to high nutrient concentrations in the removed bark. Loss of N in the Burn treatment exceeded whole tree N losses through combustion of N held in the harvest residues and litter layer. The majority of K leached from the residues prior to burning and a relatively small fraction of the base cations were lost from the partially decomposed residues during burning. Ash containing substantial amounts of Ca and relatively large amounts of N and Mg remained after burning. Surface soil Ca and Mg was significantly increased by the ash which moved into the soil with rainfall directly after burning. Rapid soil moisture recharge occurred within a few months after clearfelling, increasing leaching from the upper 50cm of soil. Clearfelling increased net N mineralisation rates, increasing mobile NO3-N ions in the soil surface layers. Nitrate concentration peaked and K concentration dipped in the upper soil layers of the Burn treatment directly after burning. Deep drainage and leaching (beyond 1m depth) over the 20.1 month period was, however, not significantly different between the Burn and No-Burn treatments. Rapid soil moisture depletion and nutrient uptake with new crop growth reduced leaching fluxes to levels similar to the standing crop by six months after planting. Taking the full rotation into account, clearfelling induced a short-lived spike in N and cation leaching compared with the low leaching losses in the undisturbed standing crop. Soil N mineralisation over the 20.1 month period in the burnt treatment was half that of the No-Burn treatment. Growth and nutrient accumulation was significantly higher in the fertilised treatment than in other treatments up to 2.5 years of age. Growth in the Burn treatment was greatest compared to other treatments during the first few months, but slowed thereafter. No significant growth differences were found between all other treatments from a year to 2.5 years after planting. Early growth was therefore apparently not limited by N supply despite large differences in N mineralisation between Burn and No-Burn. Foliar vector analysis indicated that fertilisation improved growth initially through increased foliar N and P at six months after planting followed by Mg and Ca at one year. The Burn treatment was not nutrient limited. These growth results contrasted with similar international research on sandy tropical sites where growth was reduced after residue removal and increased after residue doubling. The combined nutrients released from pools in the litter layer or ash and soil in addition to atmospheric inputs were sufficient to provide most nutrients required to maintain similar growth rates across all treatments. This demonstrated the importance of residue derived nutrients to early growth nutrient supply. Reduced N mineralisation through a lack of substrate may limit N supply later in the rotation where residue had been removed. Construction of a nutrient budget for the system revealed that high levels of atmospheric inputs have the potential to partially replenish a large proportion N, K, and Ca lost during clearfelling, provided losses are constrained to stemwood removal only. However, loss of Mg that occurred primarily through leaching may not be replaced under the low Mg inputs recorded in this study. Larger nutrient removals (i.e. stemwood plus other plant parts) placed a heavier reliance on the small soil nutrient pools at this site which can limit future productivity. More intense harvesting and residue management practices dramatically increased the risk of nutrient depletion. Losses of specific nutrients depended on a combination of clearfelling biomass removal, residue burning and subsequent leaching. Nitrogen losses due to harvesting and burning were more substantial than those due to leaching. Mg and K losses depended most strongly on the time after clearfelling before re-establishment of the new crop and rainfall patterns, while Ca and P losses depended directly on the amount of biomass removed. Depletion risk was the greatest for Mg and K through rapid leaching, even after stem wood only removal. Deep root uptake and deep drainage with associated cation loss needs to be investigated further to quantify ecosystem losses and recovery of cations displaced beyond 1m. Atmospheric deposition is one of major factors countering nutrient losses. However, atmospheric inputs may not be reliable as these may lessen in future through pollution control legislation and climate change. Changes in growth rate under poor nutrient management practices are small and difficult to detect relative to the large impacts of changing weather patterns (drought), wildfire and pest and disease. This makes it difficult to prove nutrient related growth decline. It may be possible that improvements in genetics, silvicultural technologies and atmospheric inputs may also be masking site decline (in general) and in part explain the lack of evidence of a growth reduction in the region. As the poorly buffered sandy soils on the Zululand Coast are at risk of nutrient depletion under the short rotation, high productivity stands, it may be necessary to stipulate more conservative harvesting and residue management practices. A more conservative stem-wood only harvesting regime is recommended, retaining all residues on site. Residue burning should be avoided if N losses become a concern. The length of the inter-rotation period must be kept short to reduce cation leaching losses. Site nutrient pools need to be monitored and cations may eventually need to be replenished through application of fertilisers or ash residues from pulp mills. Management practices therefore need to be chosen based on the specific high risk nutrients in order to maintain a sustainable nutrient supply to current and future plantation grown Eucalyptus.

The objective of this research is to investigate the food security, food diversity and coping strategies used to access food in households in the Eastern Cape rural village of Timane in Idutywa, Eastern Cape, South Africa. A cross-sectional survey design was used in which a Coping Strategy Index questionnaire designed by Maxwell and Caldwell (2008) and a HDD questionnaire was used to gather data interviewing respondents. This study was conducted in the rural community of Timane which was divided into geographical groups from which household were randomly chosen. A total of 60 adults representing 60 selected households were interviewed to provide information on household dietary diversity. Data was collected on the socio-biographic and HHD parameters of households. Data was analyzed and presented as correlation, percentages, means and SDs. Up to 72% of household received state grants and the Spearman’s correlation between number of children and HDD score was r = 0.38 while that between number of adults in households and HDD score was r = -0.93. Food security in the Timane community largely depends on state grants and HDD increases moderately with the increase in children and decreases with the increase in adults per household. The majority of the households (72%) received state grants as a source of income within which old-age pensions constitute 28% and child grants 38%. The Spearman’s correlation coefficient between the number of children in households of respondents and CSI was 0.78 (P < 001) while that between the number of adults in households and CSIS was 0.2 (P < 001). Household in the rural community of Timane community were found to be food insecure and this gets severe with the increase in the number of children in households. / Life and Consumer Sciences / M. A. (Human Ecology)

Baby spinach (Spinacia oleracea L.) is considered to be the one of the extremely nutritious vegetables, rich both in phytochemicals and core nutrients. Nowadays, phytochemicals in plants are raising interest in consumers for their roles in the maintenance of human health. Variation in content of bioactive compounds and core nutrients is the main concern in vegetable production. Factors such as cultural practices specially fertilization, may affect the nutritional and medicinal properties of the plants Therefore, three parallel trials for NPK to investigate the response of baby spinach leaves to nitrogen (N), phosphorus (P) and potassium (K) on chemical composition were conducted, with treatments arranged as follows: 0, 45, 75, 105, 120 kg·ha-1 N and P and 0, 60, 85, 106, 127, 148 kg·ha-1 K in a randomized complete block design (RCBD) with four replications. The results demonstrated that, application of nitrogenous, phosphorus, potassium fertilizers significantly increased the total phenolic content, total antioxidant activity, total flavonoid content and vitamin C while magnesium, iron, zinc and selenium did not exhibit significant response to all treatments applied. The increase in concentrations on total phenolic content, total antioxidant activity, total flavonoid content and vitamin C was observed, reaching maximum at 45 kg·ha-1 N, 75 kg·ha-1 P and 85 kg·ha-1 K. The optimum rates of 45 kg·ha-1 N, 75 kg·ha-1 P, 85 kg·ha−1 K were then used to formulate the NPK treatment combinations as follows: 0, 30: 30: 40, 45:45:60, 60:60:70, 75:75:90 kg·ha-1, arranged in a RCBD with three replicates. The results showed that total phenolic content, total antioxidant activity , total flavonoid content and vitamin C reached maximum in baby spinach leaves at N45:P45:K60 kg·ha-1. / Agriculture and  Animal Health / M. Sc. (Agriculture)