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Item 1H-NMR-based metabolomics study of Rifafour in a healthy Kramnik (C3HeB/FeJ) tuberculosis mouse model(2025-11) Omotayo, OP; Bhengu, S; Lemmer, Yolandy; Venter, K; Mason, SStandard treatment for tuberculosis (TB)typically involves the use of four first-line medications, namely, pyrazinamide, isoniazid, rifampicin, and ethambutol. Rifafour is a tablet that consists of a combination of these four anti-TB medications. Immediate TB treatment, typically lasting up to 14 weeks in the hospital as an inpatient and up to 6 months as an outpatient, is imperative to kill the bacteria responsible for TB. However, the anti-TB medication itself is hepatotoxic and can cause several health concerns. To elucidate these metabolic consequences, this study used an untargeted 1H-NMR metabolomics approach to investigate the systemic metabolic effects of anti TB medication administered over 14 days to healthy Kramnik (C3HeB/FeJ) mice– a mouse model commonly used in TB studies. Hippuric acid (p < 0.01), indoxyl sulfate (p < 0.05), phenylacetylglycine (p < 0.01), and tryptophan (p <0.05) remained significantly decreased in the urine throughout the14-day TB drug treatment period, whereas in the feces, choline (p < 0.05) and succinic acid (p < 0.01) remained consistently perturbed. Serum collected on day 14 showed significant (p < 0.05) concentrations of glucose, taurine, glycine, uracil, histamine, and allantoin, all of which were upregulated in the TB drug-treated group. This study implies that changes in systemic metabolism directly from TB treatment should be noted and considered when examining animals/patients with active TB on similar TB treatment. That is, these findings highlight the need to distinguish drug-induced metabolic abnormalities from those resulting from infections, consequently aiding the interpretation of metabolomic data in tuberculosis research and improving the development of more accurate therapeutic and diagnostic approaches. Hence, future studies can focus on the perturbed metabolites from TB and account for metabolites resulting from anti-TB medication, as shown in this study.Item 2D MXenes nanomaterials for removal of organic wastewater contaminants(CRC Press, 2024-12) Mdlalose, Lindani M; Hlekelele, Lerato; Chauke, Vongaini PThe research and development of two-dimensional (2D) materials was prompted and advanced after the discovery of the remarkable physical properties of single/multiple layered graphene. This hastily encouraged more research on 2D materials in the form of manipulating the structure of graphene through exfoliation, altering the starting material with readily available layered precursors such as graphite-like hexagonal boron nitride or dichalcogenides or even layered oxides [1]. This then stimulated the development of more 2D materials including the birth of MXenes. MXenes are a group 2D transition metal carbides, carbonitrides, and nitrides discovered in 2011 [2]. Their single flakes are denoted by a chemical formula Mn+1 Xn Tx (n = 1 to 4), which designates transition metals alternating layers (M) enclosed by carbon/nitrogen (X) layers with attached terminations Tx (-O2 , -F2 , -OH2 , -Cl2 ) on the external transition metal surfaces [3]. Due to their intriguing electrical and optical properties, they play numerous roles in photodetectors. Additionally, their distinctive mechanical, chemical, and physical properties allow MXenes to be altered by various surface terminations and transition metals. The atomically narrow structure of 2D MXenes makes it an appropriate alternative material for water purification technologies. Additionally, its large surface area, excellent mechanical strength, and numerous functional groups on their surfaces make it a suitable candidate for the uptake of contaminants from aqueous medium [4]. MXenes water purification interest is facilitated by its unique adsorptive, antibacterial, and reductive properties, which are further augmented by high electrical conductivity. With the intensive industrialization and vast agricultural systems, the release of toxic contaminants into ground and surface water continues to be a strain on the environment. In this chapter, the potential use of 2D MXenes derivatives for organic contaminants (such as dyes, antibiotics, and pharmaceuticals) removal is addressed. This entails mechanistic pathways of using MXene-based materials as adsorbents, water purification membranes, and photocatalysts. The ability of MXenebased composites in showing catalytic activity toward diverse pollutants and superior selectivity toward specific pollutants will be discussed.Item A comprehensive review of metal-organic frameworks sorbents and their mixed-matrix membranes composites for biogas cleaning and CO2/ CH4 separation(2024-09) Duma, Zama G; Makgwane Peter R, MN; Masukume, Mike; Swaartbooi, Ashton M; Rambau, Khavharendwe; Mehlo, Thembelihle; Mavhungu, TshidzaniMetal-organic framework (MOF) sorbent materials have recently gained considerable attention in gas separation technology. This is because of their unique structural properties, such as high gas permeability and selectivity promoted by large porosity and high surface areas. Integrating MOF fillers with polymer membranes to construct mixed-matrix membranes (MMMs) has enhanced gas separation and capture performance and stability. This review provides a comprehensive current status development in MOFs and their integrated MMMs composites with focused applications in biogas cleaning for the removal of common trace impurities such as hydrogen sulfide (H2S), ammonia (NH3), siloxanes, and moisture and upgrading of the subsequent carbon dioxide/methane (CO2/CH4) mixture to bio-methane and biogenic CO2. We highlight the structural properties and descriptors critical for designing MOF sorbents and MOF-based MMMs to improve their adsorption capacities and separation efficiency in biogas cleaning and upgrading. The tuneable surface modifications of MOFs boasted by the surface-endowed basic-acidic sites and coordinated open metal sites effectively provide high adsorption capacities and separation selectivities in biogas processing. The combination of MOFs and membranes offers high separation efficiencies of biogas-derived CO2 and CH4 for their diverse potential downstream utilisation. Future perspectives on advancing further developments in MOF sorbents and MOFs-based MMMs for biogas cleaning and upgrading to access sustainable and green derivatives with fewer carbon footprints while beneficiating wastes for adopting a circular economy are highlighted to provide solutions to the shortcomings.Item A new dawn: Vitalising translational oncology research in Africa with the help of advanced cell culture model(2025) Klima, S; Hurrell, Tracey; Goolam, M; Gouws, C; Engelbrecht, A-M; Kaur, M; Van den Bout, IThe advent of in vitro models such as induced pluripotent stem cells (iPSC) and patient derived (disease) organoids is supporting the development of population and patient specific model systems reflecting human physiology and disease. However, there remains a significant underrepresentation of non-European, especially African model systems. The development of such models should be enthusiastically embraced by Sub-Saharan African countries (SSAC) and middle-income countries (LIMC) to direct their own research focused on the improvement of health of their own populations at a sustainable cost within their respective funding environments. Great care needs to be taken to develop national frameworks to direct, sustainably fund and support such efforts in a way that maximises the output of such models for the investment required. Here, we highlight how advanced culture models can play a role in vitalising local healthcare research by focusing on locally relevant health care questions using appropriate cell culture models. We also provide a potential national platform example that could maximise such output at the lowest cost. This framework presents an opportunity for SSAC and LMIC to base their healthcare research on locally relevant models to ensure that developed health care initiatives and interventions are best suited for the populations they serve and thus represent a reset in global health care research at large.Item A retrospective cohort study to determine COVID-19 mortality, survival probability and risk factors among children in a South African province(2026-01) Tantoh, Asongwe L; Mokoatle, MC; Mbonane, TPNumerous factors contributed to coronavirus 2019 (COVID-19) disease recovery and death rates. In many countries, socioeconomics, morbidities, the experience of symptoms and access to healthcare services are major contributors to recovery and death rates. A retrospective cohort study was conducted to determine the morbidity, mortality, survival probability, and risk factors associated with COVID-19 among children in the Free State province, South Africa. A total of 846 patients’ records were used in the study. Using SPSS version 28 software, survival probability was determined using Kaplan–Meier estimation curves and Cox regression was used to determine the effect of sociodemographics and clinical manifestation information on time of death. The COVID-19 mortality rate was 13.12% in our study. There were more female patients (60%) than male patients (40%). In total, 71 patients had two or more morbidities, while 414 patients were asymptomatic. Patients between 5 and 18 years old were at twice the risk of dying of COVID-19, and male children were at a higher risk as well. Having more than one symptom was also a risk for dying in this study. Severe COVID-19 is attributed to numerous factors, and these are closely associated with surrounding environments and public health systems. The findings are important for the clinical management of similar diseases and circumstances in the future.Item A review of weathering studies in plastics and biocomposites— Effects on mechanical properties and emissions of volatile organic compounds (VOCs)(2024-04) Nzimande, Monwabisi C; Mtibe, Asanda; Tichapondwa, S; Mathew, Maya JPolymeric materials undergo degradation when exposed to outdoor conditions due to the synergistic effects of sunlight, air, heat, and moisture. The degradation can lead to a decline in mechanical properties, fading, surface cracking, and haziness, attributed to the cleavage of the polymer chains and oxidation reactions. Accelerated weathering testing is a useful technique to evaluate the comparative photodegradation of materials within a reasonable timeframe. This review gives an overview of the different degradation mechanisms occurring in conventional plastics and bio-based materials. Case studies on accelerated weathering and its effect on the mechanical properties of conventional plastics and biocomposites are discussed. Different techniques for analysing volatile organic emissions (VOCs) have been summarized and studies highlighting the characterization of VOCs from aged plastics and biocomposites after aging have been cited.Item A review on material extrusion additive manufacturing of polycarbonate-based blends and composites: Process-structure–property relationships(2025-04) Mehrabadi, NR; Pircheraghi, G; Gasemkhani, A; Sanati, PH; Shahidizadeh, A; Kaviani, A; Ray, Suprakas SPolycarbonate (PC) is a valuable engineering polymer with numerous technical characteristics like desirable mechanical properties, high heat resistance, chemical resistance, optical clarity, and electrical insulation capabilities. Therefore, it finds extensive use in aerospace, automotive, consumer goods, optics, medical devices, and electronics. Materials extrusion additive manufacturing offers several advantages, such as customized geometry, minimal material waste, cost-effectiveness, and ease of material modification. Accordingly, PC has recently emerged as a robust and durable additive manufacturing material. This review aims to investigate how printing parameters in materials extrusion additive manufacturing affect the properties of PC and PC-based materials, with a specific emphasis on mechanical properties. The main drawbacks associated with purelaments, like high PC fi print temperatures, warping tendencies, and a propensity to retract during printing, are also discussed. Considering the significant demand for developing PC blends and composites tailored for application in material-extrusion additive manufacturing, the influence of different types of fillers, including polymeric, metallic, and ceramic, on improving the mechanical behavior is then reviewed. This paper explores the diverse applications of additively manufactured PC parts, especially within advanced areas like aerospace, electrical engineering, and medicine. Lastly, prospects and challenges are presented in the review.Item A review on thermally induced phase separation technology in the fabrication of microporous polymer membrane devices for sustained-repellent delivery: Crystallization and morphological studies(2024-08) Tewo, RK; Mapossa, AB; Ray, Suprakas S; Mhike, W; Sundararaj, UThis article reports recent advances in thermally induced phase separation technology in fabricating microporous scaffold polymeric membranes as devices suitable for the controlled release of insect repellent. The key aspects, such as the crystallization behavior and morphological study of the polymeric membrane-based repellent, were reported and discussed. Studies demonstrated that trapping of such repellents into microporous polymeric materials can be achieved by spinodal decomposition of the polymer/liquid repellent system. Usually, solubility is enhanced at elevated temperatures. Rapid cooling of such solution below the UCST leads to the formation of cocontinuous phase structures by decomposition. The polymer then forms an open-cell structure with the repellent trapped inside. Approaches to forming such an open-cell polymer structure containing mosquito repellent were successfully performed and confirmed with the SEM and POM techniques. It showed the structure of a polymer and liquid repellent prepared by spinodal decomposition, providing proof that thermally induced spinodal decomposition is a route to trap liquid mosquito repellent into a microporous polymer matrix. Additionally, the effects of polymer type, repellent nature, cooling conditions, and fillers on the morphology and performance of TIPS membranes are also discussed. Finally, challenges in developing microporous polymeric membrane-based repellent using TIPS technology are addressed.Item Active nanocomposite films based on low density polyethylene/organically modified layered bouble hydroxides/thyme oil to retain retail shelf life and quality of hass avocados(2020-12) Kesavan Pillai, Sreejarani; Sivakumar, D; Ray, Suprakas S; Obianom, P; Eggers, Sharon K; Mhlabeni, TIn this study, the ability of an active film containing volatile bioactives in post-harvest disease control and preservation of quality in avocados is explored as a non-traditional treatment method. Antimicrobial transparent flexible trilayer low density polyethylene (LDPE) films containing organically modified layered double hydroxides (OLDH) and plant bioactive-thyme oil (TO) were made using single step blown film extrusion. Antifungal effects of the packaging in comparison to commercial treatment and untreated control showed considerable reduction in anthracnose disease events in ‘Hass’ cultivar of avocados while improving the fruit quality. 2wt% OLDH loading improved the oxygen and moisture barrier properties while not affecting the transparency of the film. The results suggest that the synergistic effect of barrier and antimicrobial properties of the controlled volatile bioactive release of the nanocomposite film can be utilised as a prospective strategy to modify the headspace gas composition to combat anthracnose disease in avocados.Item Active nanocomposite films based on low density polyethylene/organically modified layered bouble hydroxides/thyme oil to retain retail shelf life and quality of hass avocados(2020-11) Kesavan Pillai, Sreejarani; Sivakumar, D; Ray, SS; Obianom, P; Eggers, SK; Mhlabeni, TIn this study, the ability of an active film containing volatile bioactives in post-harvest disease control and preservation of quality in avocados is explored as a non-traditional treatment method. Antimicrobial transparent flexible trilayer low density polyethylene (LDPE) films containing organically modified layered double hydroxides (OLDH) and plant bioactive-thyme oil (TO) were made using single step blown film extrusion. Antifungal effects of the packaging in comparison to commercial treatment and untreated control showed considerable reduction in anthracnose disease events in ‘Hass’ cultivar of avocados while improving the fruit quality. 2wt% OLDH loading improved the oxygen and moisture barrier properties while not affecting the transparency of the film. The results suggest that the synergistic effect of barrier and antimicrobial properties of the controlled volatile bioactive release of the nanocomposite film can be utilised as a prospective strategy to modify the headspace gas composition to combat anthracnose disease in avocados.Item Additive manufacturing of biodegradable and biobased polymers and their composites(Elsevier, 2025-01) Nkuna, CN; Nomadolo, Elizabeth N; Mhike, M; Shongwe, MB; Ojijo, Vincent O; Mathew, Maya JThe manufacturing of biobased biodegradable materials through additive manufacturing (AM) or 3D printing methods is a highly effective, sustainable, and eco-friendly technological advancement that is transforming the traditional polymer manufacturing processes and the extensive use of petroleum-based polymers. This chapter focuses on the different additive manufacturing technologies, along with a comprehensive analysis of inherent properties, processing parameters, and product specifications of various biodegradable polymer-based composites and blends. The fabrication of tailor-made structures for targeted application in the textile, food industry, construction, biomedical field, and other applications is discussed. The chapter highlights the primary challenges currently encountered when using AM as a production tool, as well as the emergence of 4D and 5D printing in AM. Finally, the chapter presents future perspectives, market analysis and provides a way to overcome the challenges associated with the 3D printing of biopolymers.Item Adsorption of NH3 and NO2 molecules on sn-doped and undoped ZnO (101) surfaces using density functional theory(2022) Dima, Ratshilumela S; Tshwane, David M; Shingange, Katekani; Modiba, Rosinah; Maluta, NE; Maphanga, Rapela RThe adsorption and interaction mechanisms of gaseous molecules on ZnO surfaces have received considerable attention because of their technological applications in gas sensing. The adsorption behavior of NH3 and NO2 molecules on undoped and Sn-doped ZnO (101) surfaces was investigated using density functional theory. The current findings revealed that both molecules adsorb via chemisorption rather than physisorption, with all the adsorption energy values found to be negative. The calculated adsorption energy revealed that the adsorption of the NH3 molecule on the bare ZnO surface is more energetically favorable than the adsorption of the NO2 molecule. However, a stable adsorption configuration was discovered for the NO2 molecule on the surface of the Sn-doped ZnO surface. Furthermore, the adsorption on the undoped surface increased the work function, while the adsorption on the doped surface decreased. The charge density redistribution showed charge accumulation and depletion on both adsorbent and adsorbate. In addition, the density of states and band structures were studied to investigate the electronic behavior of NH3 and NO2 molecules adsorbed on undoped and Sn-doped ZnO (101) surfaces.Item Advanced of Starch-Based Bioplastics(Elsevier, 2024) Mtibe, Asanda; Nomadolo, Elizabeth N; Hlekelele, Lerato; Mokhena, TC; Ofosu, Osei; John, Maya J; Ojijo, Vincent OThe potential of starch-based plastics is well-known and well-researched. In recent years, starch-based materials have been used in both commercial and industrial applications to develop biodegradable and sustainable products and address the negative impacts caused by synthetic plastic products. Synthetic plastics are derived from petroleum-based resources and are non-biodegradable, causing plastic waste pollution. Starch-based bioplastics are selected as an alternative to synthetic plastics due to their availability, renewability, sustainability, biocompatibility, and biodegradability. The conversion of starch into thermoplastic starch (TPS) will be discussed in this study. In addition, the development of starch-based bioplastics using different processing techniques such as melt extrusion, injection molding, compression molding, blown film extruder as well as 3D and 4Dprinting will be also discussed. The market analysis of starch and starch-based materials, their properties, and applications, as well as prospects to determine if starch-based bioplastics are economically and practically feasible, will be thoroughly discussed.Item Advanced therapeutic technologies for malaria, tuberculosis, HIV infection and neglected tropical diseases(Wiley, 2025-03) Dube, A; Laverty, G; Balogun, Mohammed O; Dube, A; Laverty, G; Balogun, Mohammed OWe are pleased to present this special issue to highlight advances in therapeutic technologies for infectious diseases, in particular for treatment of tuberculosis (TB), HIV/AIDS and malaria. Informative reviews as well as original research articles form part of this Issue. The world's deadliest infectious diseases TB, HIV/AIDS and malaria are responsible for close to 2.5 million deaths world-wide, each year.[1] Over 90% of deaths due to malaria occur in sub-Saharan Africa, with the majority of deaths occurring in children under 5 years of age. Infectious diseases are responsible for ≈704 million disability-adjusted life-years (DALYs) and the African region bears the highest burden, with ≈314 million DALYs; while high-income countries account for only ≈31.8 million DALYs.Item Advancements and perspectives in folate-based anticancer drugs: Bridging quantum and classical mechanics in folate receptor research(2024) Josiah, Andrea J; Govender, KK; Govender, PP; Ray, Suprakas SThis review highlights the role of computational chemistry, specifically quantum and molecular mechanics, in the development of folate-based anticancer drugs. Folate receptors (FRs) are overexpressed in cancerous cells, rendering these receptors a key focus in the design of targeted drug delivery systems. These computational tools are fundamental for analyzing drug–receptor interactions and overcoming the limitations of traditional drug development processes. A 10-year literature survey demonstrated advancements in employing FRs for targeted cancer therapy. Key findings reveal that structural modifications to folate derivatives consistently enhance binding affinities and specificity toward FRα and FRβ. Computational methodologies predicted and analyzed molecular interactions, validated by experimental data. Functional groups play a crucial role in enhancing binding stability and interaction strength within FR binding pockets. Detailed structural insights into folate derivatives and antifolates interacting with FRs have identified critical residues involved in binding, aiding the design of targeted therapeutics.Item Advancements in antimicrobial textiles: Fabrication, mechanisms of action, and applications(2025) Orasugh, JT; Temane, Lesego Y; Pillai, Sreejarani K; Ray, Suprakas SWithin the past decade, much attention has been drawn to antimicrobial textiles due to their vast potential for reducing the spread of infectious diseases and improving hygiene standards in various environments. This review paper discusses recent studies on preparation methods, modes of action, effectiveness against different microorganisms, and applications of antimicrobial textiles in diverse industries. It examines further challenges, including durability, environmental impact, and regulatory considerations, and looks at prospects for developing and integrating these novel materials. This paper intends to provide a broad-based understanding of state-of-the-art technologies and emerging trends in antimicrobial textiles by integrating existing knowledge and highlighting recent advances in this field that contribute much to improved public health and safety.Item Advances and challenges in betulinic acid therapeutics and delivery systems for breast cancer prevention and treatment(2025-09) Selepe, Cyril T; Dhlamini, Khanyisile S; Tshweu, Lesego L; Kwezi, Lusisizwe; Ramalapa, Bathabile E; Ray, Suprakas SBreast cancer (BC) is the leading cause of cancer-related death among women worldwide. Due to limited treatment options for patients with advanced BC, preventive and innovative therapeutic strategies are essential to combat this disease. Therefore, finding safe and effective anticancer treatments remains a significant challenge in the 21st century. Plant-derived triterpenoids, widely used for medicinal purposes, exhibit various biological activities. Most triterpenoids are cytotoxic to multiple tumor cells and demonstrate anticancer effects in preclinical animal models. One example is betulinic acid (BA), a natural product mainly extracted from the bark of birch trees. BA is a promising anti-tumor compound with numerous pharmacological properties. However, its poor water solubility limits its optimal therapeutic potential. Additionally, the low BA content in plants hampers large-scale production from these sources. To address these issues, extensive research has focused on producing BA through chemical synthesis and biotransformation. Furthermore, several BA derivatives have been developed through structural modifications, and various delivery systems have been created to improve solubility and enhance therapeutic efficacy. This review discusses recent advances and challenges related to BA and its derivatives in preventing and treating breast tumors, as well as the potential obstacles and future directions for improving delivery systems in BC therapy.Item Advances in CRISPR-Cas systems for blood cancer(2024-08) Monchusi, Bernice A; Dube, Phumzile; Takundwa, Mutsa M; Kenmogne, Vanelle L; Thimiri Govinda Raja, Deepak BCRISPR-Cas systems have revolutionised precision medicine by enabling personalised treatments tailored to an individual's genetic profile. Various CRISPR technologies have been developed to target specific disease-causing genes in blood cancers, and some have advanced to clinical trials. Although some studies have explored the in vivo applications of CRISPR-Cas systems, several challenges continue to impede their widespread use. Furthermore, CRISPR-Cas technology has shown promise in improving the response of immunotherapies to blood cancers. The emergence of CAR-T cell therapy has shown considerable success in the targeting and correcting of disease-causing genes in blood cancers. Despite the promising potential of CRISPR-Cas in the treatment of blood cancers, issues related to safety, ethics, and regulatory approval remain significant hurdles. This comprehensive review highlights the transformative potential of CRISPR-Cas technology to revolutionise blood cancer therapy.Item Advances in yeast probiotic production and formulation for preventative health(2024-11) Moonsamy, Ghaneshree; Roets-Dlamini, Yrielle; Langa, Cebeni N; Ramchur, Santosh OThe use of probiotics has been gaining popularity in terms of inclusion into human diets over recent years. Based on properties exerted by these organisms, several benefits have been elucidated and conferred to the host. Bacteria have been more commonly used in probiotic preparations compared to yeast candidates; however, yeast exhibit several beneficial properties, such as the prevention and treatment of diarrhea, the production of antimicrobial agents, the prevention of pathogen adherence to intestinal sites, the maintenance of microbial balance, the modulation of the immune system, antibiotic resistance, amongst others. Saccharomyces boulardii is by far the most studied strain; however, the potential for the use of other yeast candidates, such as Kluyveromyces lactis and Debaryomyces hansenii, amongst others, have also been evaluated in this review. Furthermore, a special focus has been made regarding the production considerations for yeast-based probiotics and their formulation into different delivery formats. When drafting this review, evidence suggests that the use of yeasts, both wild-type and genetically modified candidates, can extend beyond gut health to support skin, the respiratory system, and overall immune health. Hence, this review explores the potential of yeast probiotics as a safe, effective strategy for preventative health in humans, highlighting their mechanisms of action, clinical applications, and production considerations.Item Agile local manufacturing of active pharmaceutical ingredients in Africa could improve health security and economic growth(2025-08) Sagandira, Cloudius RAfter decades of dependence on imported Active Pharmaceutical Ingredients (APIs) and multilateral aid, Africa faces a critical turning point, seeking to assert control over its health and economic future. Here we discuss how agile local API manufacturing offers a strategic solution to enhance health and economic security, transforming Africa’s pharmaceutical landscape for sustainable medicine access.