Digital Knowledge Collection:

Digital literacy practices: curation and annotation associated with e-textbooks

Mon, 01 Jan 2024 00:00:00 GMT

Title: Digital literacy practices: curation and annotation associated with e-textbooks Authors: Rzyankina, Ekaterina; Msomi, Alfred Mvunyelwa Abstract: E-textbooks have gained prominence in recent years due to their advanced digital features and accessibility. This evolution has led to innovative digital literacy practices, notably curation and annotation, aimed at enhancing student comprehension of engineering concepts. These practices offer three-fold benefits: they mitigate information overload and provide a systematic learning framework for students. This is crucial in fields like engineering where contextual understanding enhances the practical application of theoretical concepts. By integrating supplementary resources and multimedia elements, e-textbooks provide a richer, more immersive learning experience. This study, focusing on these affordances in e-textbooks, utilised qualitative data from interviews with 12 first-year engineering students at a university of technology. Findings indicate that these new literacy practices hold significant potential for improving student understanding of engineering concepts. The study underscores the need for further exploration into the use of digital tools in education, highlighting their transformative potential in shaping future learning of students.

Biochemical and Physicochemical properties of malted pearl millet meal fortified with Moringa oleifera leaf powder

Thu, 12 Apr 2018 00:00:00 GMT

Title: Biochemical and Physicochemical properties of malted pearl millet meal fortified with Moringa oleifera leaf powder Authors: Oneziwe, Jackson; Obilana, Anthony O Abstract: There is continued interest in the improvement of the nutritional quality of traditional weaning foods. The high price of proprietary weaning foods, combined with bad feeding practices and late introduction of supplementary foods, are mostly responsible for aggravating the disorder (malnutrition) among children (Dutra-de-Oliveira, 1991). Good nutrition, particularly during infancy and childhood can promote adequate physical and mental development. Certain nutrients such as protein, fats and oils in food maintain life; through being used for cells growth, repair, and regulation of function (Bergger, 1998). Description: Conference Poster

Antioxidant, antimicrobial and antiverotoxic potentials of extracts of Curtisia dentate

Sat, 01 Jan 2011 00:00:00 GMT

Title: Antioxidant, antimicrobial and antiverotoxic potentials of extracts of Curtisia dentate Authors: Doughari, James Hamuel; Ndakidemi, Patrick Alois; Human, Izanne Susan; Spinney, Benade Abstract: The potentials of Curtisia dentata as antimicrobial, antioxidant and antiverotoxin against environmental isolates of E. coli and Acinetobacter spp, the presence of phytochemicals and some organic compounds was investigated. The highest concentration of phytochemicals and organic compounds such as anthraquinones, alkaloids, essential oils, glycosides, phenols, steroids, saponins and tannins and the organic compounds quinones, anthocyanins, amines and carboxylic acids were found in the stem bark ethanol extracts compared to other parts of the plant or solvent extracts. Antimicrobial activity as relative inhibition zone diameters (%) ranged between 8-28% (MIC values, 100- 2500 mg/ml) against E. coli serotypes, and 10-28% (MIC, 100-850mg/ml) and 6-28% (MIC, 150-2500 mg/ml) against A. lwoffii and A. haemolyticus respectively. The extracts demonstrated inhibitory action against the expression of both Vtx1 and Vtx2 genes in both E. coli and A. haemolyticus strains with the ethanol extracts demonstrating the highest antiverotoxic activity compared to other solvents. The ethanol root bark extracts consistently showed the highest DPPH radical scavenging activity (62.43%), total phenol content (TPH) (57.62 26 mg GAE/g) and reducing power (RP) (41.32%), followed by those of the stem bark and leaf extracts with the respective values of 54.68%, 37.77 mg GAE/g and 21.83%. Ethanol extracts demonstrated the highest values for both DPPH, TPH and RP followed by dichloromethane, hexane, acetone and distilled water in this order. C. dentata can be used to source novel antimicrobial agents for the treatment of verotoxic bacterial infections.

Antioxidant and inhibitory effect of Maillard reaction products (MRPs) against enzymatic browning of Granny smith apples

Fri, 01 Jan 2016 00:00:00 GMT

Title: Antioxidant and inhibitory effect of Maillard reaction products (MRPs) against enzymatic browning of Granny smith apples Authors: Vhangani, Lusani Norah; Van Wyk, Jessy; Thys, Xabisa; Silabele, Sonia Abstract: Maillard reaction products (MRPs) were prepared from glucose-casein (1:2 w/w) model systems at pH 8 heated at 60 and 75 °C for 6, 12 and 24 h. Browning intensity (BI) and pH reduction were monitored throughout the reaction. The antioxidant activity (AA) of resulting MRPs was evaluated through metal chelation (MC), reducing power (RP) and 1,1-Diphenyl-2-picryl-hydrazyl radical scavenging (DPPH-RS). Inhibition of enzymatic browning was evaluated through colour change on the CIELab system and the polyphenolase assay. The pH of MRPs decreased (p < 0.05) as the reaction temperature and times increased, which in turn coincided with an increase (p < 0.05) in BI and RP. DPPH-RS of MRPs increased as the temperature increased from 60 to 75°C, although a sudden decrease (p < 0.05) was observed at 75°C for 12 and 24h. The loss in AA was attributed to the formation of high molecular weight melanoidins known to exhibit lower AA. MRPs which resulted in a pH drop below 5 were effective in inhibiting polyphenolase activity. This enzyme has an optimum pH in the range of 5-7. Most MRPs produced after 6 h did not show a pH reduction of less than 5, however, these were able to inhibit the polyphenolase activity. This inhibition was attributed to MC properties of MRPs on the active site of the enzyme for all model systems.