DSpace Repository

Welcome to the NWU Repository, the open access Institutional Repository of the North-West University (NWU-IR). This is a digital archive that collects, preserves and distributes research material created by members of NWU. The aim of the NWU-IR is to increase the visibility, availability and impact of the research output of the North-West University through Open Access, search engine indexing and harvesting by several initiatives.

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Recent Submissions

Characteristics of bacteria associated on biofilms in freshwater microcosms
(North-West University(South Africa)., 2025) van den Heever, Aneli; Bezuidenhout, J.J; Molale-Tom, L.G; Mienie, C.M.S
Freshwater pollution is an ever-growing concern, due to the increasing population growth combined with a rapidly decreasing natural resource capacity, such as water. The possibility of significant problems arising from water scarcity can lead to negative consequences for the environment and its inhabitants. One of the biggest water pollution concerns is microplastics. Microplastics can serve as vectors for potentially harmful bacterial groups and reservoirs for antibiotic-resistance genes. An increase in the water pollution rate, coupled with the overused and improper use of antibiotics, contributes towards the surge of antibiotic-resistant bacteria within the environment. In light of these concerns, this study aimed to determine the characteristics of bacteria associated with biofilms surrounding microplastics in a simulated freshwater environment. The first objective was to examine the bacterial colonisation on microplastics and wood substrates through scanning electron microscopy in microcosm experiments involving river water and wastewater treatment plant effluent obtained from the North West Province in South Africa. The second objective was to determine the characteristics of the bacterial isolates throughout the incubation period. The third objective was to perform Sanger sequencing of these purified isolates to aid in the identification of the bacteria found in biofilms surrounding the microplastics and wood substrate. The fourth objective was to perform next-generation sequencing targeting the 16S rRNA bacterial genes in order to characterise the bacterial community composition (BCC) within the plastisphere post-incubation. The microcosm study revealed that bacterial colonisation of various substrates occurred within 72 hours after incubation. Scanning electron microscopy images indicated that biofilm development happened within a 28-day period, revealing diverse microbial communities on the different substrates-the surface properties combined with the increased nutrient load assisted with the microbial attachment more readily. Scanning electron microscopy images revealed that the wood particles had a higher degree of colonisation than the microplastic particles due to the surface properties and organic composition. Among the 877 pure bacterial isolates tested for various extracellular enzymes, haemolysis was the most prevalent compared to DNase, resulting in 51 isolates used for further identification. Virulence testing revealed varying levels of antibiotic resistance across the 51 microbial isolates, with 16 presenting pathogenic potential. The 16 potentially pathogenic isolates underwent Sanger sequencing, and the phylogenetic relationship was determined, with a focus on eight bacterial species. Aeromonas sp. and Stenotrophomonas koreensis were among the potentially pathogenic bacteria detected. The microbial composition of the source water and plastisphere were ascertained and compared. The source water showed variation in species composition but a reduced species richness, while the plastisphere exhibited higher species richness and diversity. Next-generation sequencing revealed that Hyphomonadaceae was the dominant family within the plastisphere, belonging to the order Caulobacterales, within the Alphaproteobacteria class and Proteobacteria phylum. This study confirmed the presence of pathogenic bacteria and a significant bacterial composition on microplastics, highlighting their role as vectors for pathogens and the transfer of antibiotic-resistance genes within freshwater environments. Furthermore, the ongoing discharge of inadequately treated wastewater and the persistence of plastic particles can introduce waste-related pathogens into microplastic biofilms, thereby posing a significant concern for future generations. These findings highlight the urgent need for improved wastewater treatment practices and effective plastic waste management to protect freshwater ecosystems and public health.
Incorporating Sesotho in teaching Grade 10 History through medium of English using a PALAR approach
(North-west University, 2025) Noosi, Kabelo Elijah; Kaiser, Kotie; Dlavane, Dolly; Olivier, Dawid
This study explored relevant multilingual pedagogies in teaching History in Grade 10 that can assist History educators to incorporate Sesotho in the teaching of History through the medium of English. Furthermore, this study attempted to create awareness and capacitate History educators with multilingual pedagogies and the utilisation of these pedagogies in their own classrooms. Mezirow's transformational learning theory was adopted in this study, which seeks to explore solutions to identified problems in professional spaces through critical reflections. Participatory Action Learning and Action Research (PALAR) was adopted as a research methodology, which is rooted in the transformative paradigm aiming to promote social justice for the historically marginalised groups and foster emancipatory teaching and learning. Purposive sampling was used to recruit History educators who are Sesotho speakers in Botshabelo, Free State province, who participated and generated data in an action learning group. The findings of this study indicate that there is a need for creating awareness of the relevance of multilingual pedagogies among History educators and that the exploration and usage of multilingual pedagogies, such as translanguaging, code-switching and Ubuntu translanguaging, make teaching History more effective because these strategies tap into the linguistic repertoires of the learners and give them epistemic access to History knowledge.
Consumers’ knowledge and utilisation practices regarding plastic food and beverage packaging and containers
(North-west University, 2018) van den Berg, Magdi Susan; van der Merwe, Daleen; Louise, Wyma
Plastic packaging and containers play an important role in the food industry. They provide product information, aid in preventing food spoilage, and offer protection during transport and storage. However, these packaging materials or containers may leach harmful chemical substances and compounds into food and beverages. The leaching process may be accelerated during the misuse and reuse of these plastic products. Consumers are mostly familiar with the chemical substance Bisphenol A (BPA), "an endocrine-disrupting chemical (EDC)", which has attracted attention worldwide. BPA and EDCs are associated with different diseases and health problems, since they alter and interfere with natural hormones. Research has indicated that the accumulation of BPA and other EDCs from a variety of sources pose threats to human development and health. In addition, substitute chemicals performing similar functions to that of BPA in plastics occur in "BPA-free" plastic products. Research was therefore done to determine consumers' knowledge and utilisation practices regarding plastic as food and beverage packaging and containers. The aim of this study was to investigate and describe consumers' subjective and objective knowledge and their utilisation practices regarding plastic food and beverage packaging and containers in order to assess if consumers utilise these plastics safely. The information sources that consumers consult regarding the correct use of plastic packaging and containers as well as BPA and other harmful chemicals were also determined. The Social Cognitive Theory (SCT) was used as theoretical perspective in order to frame the objectives of this study, and aided in the understanding of consumer knowledge, their learning processes, and their behaviour and how to alter it. A quantitative, cross-sectional, descriptive survey was used for this study. Information was obtained from consumers between the ages of 18 to 35 years, from different backgrounds. Non-probability, purposive sampling was used and 293 respondents completed the online questionnaire. The results indicated that although most respondents had a fair subjective knowledge, they lacked objective knowledge regarding plastic food and beverage packaging and containers. Moreover, while some respondents had adequate to good knowledge of some of the identified factors, their utilisation practices did not reflect this knowledge since most types of packaging and containers were used incorrectly. A total lack of knowledge regarding plastic identification codes was identified. Respondents indicated that they obtained product-related information from formal and informal information sources, but trusted formal sources more. In a developing country such as South Africa, informal sources are more easily accessible, and respondents may therefore use them more. In contrast to previous research conducted in South Africa regarding consumer knowledge in other food contexts, no practically significant associations were indicated between subjective and objective knowledge. Additionally, only slight differences/tendencies were observed between respondents of different ages, genders and ethnicities. In conclusion, results confirmed that consumers are ill-informed regarding the correct utilisation practices of plastic products in a food context, and that they are unaware of the harmful chemicals in plastics and their associated health effects. These findings highlight the need for consumer education regarding the correct utilisation practices of plastic food and beverage packaging and containers and education regarding plastic identification codes, paving the way for follow-up intervention research. Legislation and policy makers are also recommended to take action regarding harmful chemicals found in food packaging and containers, since doing so may lead to an overall improvement of consumer health.
The role of knowledge on the effect of external influences on the food information search of working female consumers
(North-west University, 2019) Nel, Marli; van der Merwe, Daleen; Wyma, Louise
Serving as the gatekeepers of their households, women are also part of the labour force. Research indicates that women are still mainly responsible for establishing healthy eating patterns in their households, thus in general responsible for selecting the food products that enter their homes. However, working female consumers often lack the time and sometimes sufficient knowledge to make informed, healthy food decisions. According to previous research, objective knowledge and subjective knowledge are both strongly associated with self-reported nutritional label use, regardless of health-related attributes. The influence of objective and subjective knowledge in decision making begins to differ when consumers are unfamiliar with a product. Consumers should possess sufficient objective knowledge to make reliable food choices when shopping for groceries. Insufficient objective and subjective knowledge lead to avoidance of the nutritional information on food labels. The study proposes that having the necessary objective and subjective knowledge regarding healthy foods may assist working female consumers during their pre-purchase information search by using the relevant information on food labels, while external influences may also play a role in their decisions. Research on the importance of external influences during the in-store food label search for high-frequency food products is needed to understand particular influences that working female consumers regard as important during purchasing decisions. Consumers rely on their knowledge and often external aspects such as price, brand and other marketing efforts during their pre-purchase information search. There is, however, a gap in current literature regarding the association between knowledge about the healthiness of food and external influences during full-time working female consumers' pre-purchase information search regarding high-frequency food products. Therefore, this study aimed to determine the mediating role of objective and subjective knowledge of working women regarding the healthiness of food in the effect of external influences on their pre-purchase information search for high-frequency food products. This study employed a quantitative, descriptive, cross-sectional survey design. Data were collected from a purposively selected sample of South African full-time working female consumers between the ages of 18 and 65 years (N = 223) using online questionnaires. Construct validity was determined for all the scales using exploratory factor analysis. Internal reliability of the yielded factors was ensured using Cronbach alpha values. The results indicated that respondents had high levels of objective knowledge regarding the healthiness of food (82.43% correct) and SK (measured on a five-point Likert scale) of frequently consumed healthy foods (mean = 4.03) and nutrient intake limitations (mean = 3.82). Besides, convenience (mean = 3.74), as well as price and product comparisons (mean = 3.53) were considered to be more important external influences (measured on a five-point Likert scale) than visual attributes (mean = 2.56) during these respondents' information search. The importance of these aspects may be due to the lack of time they have to search for information in-store. The respondents indicated that expiry date (mean = 3.30), nutritional value and ingredients (mean = 2.54) were more important (measured on a five-point Likert scale) aspects on food labels than claims (mean = 2.19) and allergens (mean = 2.17). These findings agree with previous research stating that consumers with adequate levels of knowledge are more likely to make use of nutritional information and ingredient lists. In conclusion, according to the structural equation model, objective knowledge or subjective knowledge did not mediate external influences such as price, visual attributes, and convenience, since these influences had a direct influence on the in-store information search process based on the labels of frequently purchased food. Objective knowledge has had no mediating effect on the pre-purchase information search process. These findings are contradicting to previous research showing that subjective knowledge has a positive effect on the use of external factors. However, subjective knowledge has had a mediating effect on respondents experiencing the external influence of a family need for exclusion of some ingredients (allergens and those due to diabetes) during their food label-based information search. Therefore, it is important to understand that subjective knowledge has only had a mediating effect on respondents' information search in-store, when exposed to a family-related external influence. The study thus contributes to a better understanding of this population group's information search process and indicates that the women in the study are still playing a gatekeeping role in the wellness of their households.
Aneli van den Heever