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Isolation, purification and characterization of inulin and fructooligosaccharides from chicorium intybus and inulinase from aspergillus niger

- Mavumengwana, Vuyo Bhongelethu

  • Authors: Mavumengwana, Vuyo Bhongelethu
  • Date: 2005
  • Subjects: Aspergillus , Inulin , Chicory -- South Africa
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:3954 , http://hdl.handle.net/10962/d1004013 , Aspergillus , Inulin , Chicory -- South Africa
  • Description: Inulin is a non-digestible carbohydrate fructan polymer consisting mainly of β (1→2) fructosyl fructose links. Enzymatic hydrolysis of inulin by inulinase results in the production of low D.P (degree of polymerization) oligosaccharides also called fructooligosaccharides(FOS). Isolation of inulin from chicory root (Chicorium intybus) was achieved by first, extraction using deionized water (600C), followed by carbonation (0.1 M Ca(OH)2 and CO2 gas). This was filtered in order to remove the non sugars, thereafter, treated successfully with polyamide 6 powder. A cation exchanger and an anion exchanger were used to further exclude other components such as tannins and pigments. The extracted inulin was quantified using the Somogyi-Nelson colourimetric assay. Chicory root (207 g, 30 % being water) yielded 30 g of the raw extract. A 100 mg of the raw extract was assayed and found to contain 11 % yield of inulin which was 80.2 % in purity and 4 % free fructose. Analysis of the crude and purified inulin extracts on the MALDI TOF spectrometry showed the samples to have a DP of 2 to 22 and 2 to 27 respectively. Maximum inulinase production from Aspergillus niger grown on inulin was observed after 60 hours. The enzyme activity was found to be 1.168 U/ml with a temperature and pH optimum of 30 °C and 7.7 respectively. The enzyme proved to be unstable as it progressively lost its total activity during attempts at purification.
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  • Date Issued: 2005

It's a happy day

- Preformer not specified, Composer not specified, Dargie, Dave

Knowledge levels of school learners before and after a life skills program on rape and child abuse

- Britz, Cecelia Adonia

  • Authors: Britz, Cecelia Adonia
  • Date: 2005
  • Subjects: Rape -- Prevention , Child abuse -- Prevention , School children -- Life skills assessment -- South Africa -- Port Elizabeth
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: vital:11017 , http://hdl.handle.net/10948/360 , Rape -- Prevention , Child abuse -- Prevention , School children -- Life skills assessment -- South Africa -- Port Elizabeth
  • Description: Due to the early age at which children are exposed to rape and child abuse, preventative programs should be implemented as early as possible. Schools provide ample opportunity to reach learners of all ages. Educators have regular contact with learners and have a key role to play in the implementation of comprehensive health and education life skills programs. Non-Governmental Organisations (NGO) can link up with schools to combat abuse that affects children in South African communities. The Ubuntu Education Fund requested the Health and Development Research Institute (HDRI) of the University of Port Elizabeth to assist with the evaluation of the Mpilo-Lwazi life skills program for grade 6 to 9 learners at 5 primary and 5 secondary schools in the Nelson Mandela Metropole. The schools were selected by non-probability convenience sampling and the learners via simple random sampling. The life skills program addressed issues of HIV/AIDS, STI and rape and child abuse and the requested evaluation encompassed both the quantitative pretest-posttest assessment of knowledge plus a qualitative focus group assessment of perception of the content and presentation of the life skills program. A multiple pretest-post-test quasi-experimental research design was used. This study focused on the quantitative aspect of rape and child abuse and aimed to describe learners’ base line knowledge before receiving education in rape and child abuse life skills programs and acquired knowledge after the program had been implemented. Descriptive statistics were employed to describe the pre and post test information and the Hotelling’s T2 was used to identify variation in profiles. Posthoc t-tests established significant differences between grades. Structured questionnaires were used to achieve the aims of the research. Results of both the quantitative and qualitative findings were collated to be presented to the Ubuntu Education Fund. The results of the study were as follows: ix The results indicated that the overall level of knowledge regarding Rape and Child Abuse among the sample of grade six to nine learners was average. A small increase in knowledge was identified in the post-test. The area most successful for knowledge increase was the section relating to general information on the victims of Rape and Child Abuse. An area where knowledge actually decreased was that on reporting the rape or abuse. Knowledge of rape and child abuse alone is not sufficient to bring about change in behaviour. Changes in beliefs, such as increased awareness that rape and child abuse are prevalent in families and communities, and attitude change are necessary to facilitate the adoption of health-promoting behaviour. Future education efforts need to introduce health educators into the Rape and Child Abuse life skills program at schools in educating the learners. The format of teaching should also take into account the preferred method of presentation indicated by the learners as this would facilitate optimal intake of information.
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  • Date Issued: 2005

Kuba wena molokazana

- Preformer not specified, Composer not specified, Dargie, Dave

Kuzade kubenini bendilandela

- Preformer not specified, Composer not specified, Dargie, Dave

Language is culture:

- Malila, Vanessa

  • Authors: Malila, Vanessa
  • Date: 2005
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/159256 , vital:40281 , https://hdl.handle.net/10520/EJC146402
  • Description: Many of us think that English dominates the web pages we surf each day. Indeed, until recently English was the predominant language for publishing online, but things are slowly changing and the presence of linguistic diversity on the Internet is starting to become a reality in the global village. The question, however, remains: how many African languages are represented in that diversity?.
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  • Date Issued: 2005

Laphalala igazi

- Preformer not specified, Composer not specified, Dargie, Dave

Late glacial and holocene palaeoclimatology of the Drakensberg of the Eastern Cape, South Africa

- Lewis, Colin A

  • Authors: Lewis, Colin A
  • Date: 2005
  • Language: English
  • Type: Article
  • Identifier: vital:6692 , http://hdl.handle.net/10962/d1006727
  • Description: Eight climatic events during the Holocene are evidenced in the East Cape Drakensberg by fluvial, archaeological and palynological deposits. Flood plain deposition under relatively moist conditions occurred in the Early Holocene, before ca. 7000 BP. Semi-arid conditions with limited fluvial activity dominated the Mid Holocene until ca. 3200 BP. Alternating flood plain erosion and deposition occurred in the Late Holocene. Four climatic events, for which there is palynological and limited archaeological evidence, have been identified in the Late Glacial.
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  • Date Issued: 2005

Learning science through two languages in South Africa

- Probyn, Margie J

  • Authors: Probyn, Margie J
  • Date: 2005
  • Language: English
  • Type: Conference paper
  • Identifier: vital:7015 , http://hdl.handle.net/10962/d1007208
  • Description: [From the introduction]: South Africa is a multilingual country with eleven national languages - nine indigenous languages and the two former colonial languages of English and Afrikaans1 - recognised as official languages in the Constitution of 1996 (Constitution of the Republic of South Africa, 1996). Despite these provisions, since the democratic elections of 1994 English has expanded its position as the language of access and power with the relative influence of Afrikaans shrinking, and African languages effectively confined to functions of ‘home and hearth’. McLean and McCormick (1996: 329 in Mazrui 2002: 269) suggest that the constitutional recognition of 11 official languages in South Africa is largely 'intended and perceived as a symbolic statement and that for instrumental purposes, English remains the dominant language in South Africa'.
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  • Date Issued: 2005

Ligand isotope vibrational spectroscopic and DFT studies of Pt(II) and Cu(I) complexes

- Medina, Gerardo Juan

  • Authors: Medina, Gerardo Juan
  • Date: 2005
  • Subjects: Ligands Spectrum analysis Vibrational spectra Infrared spectroscopy
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:4324 , http://hdl.handle.net/10962/d1004982
  • Description: Ligand-isotope labelling studies were performed on Zeise’s salt derivatives with pyridine N-oxide and quinoline N-oxide, their perdeuterated and O-18 isotopomers, C₂D₄ and ¹³CO, and the results of the vibrational analyses are reported. The isotopomers are modelled utilizing DFT calculations at the B3LYP level with the 6-31 G** basis set, and a pseudopotential level for the Pt atom. The calculated and observed structure and vibrational spectra correlate well. The crystal structures of [Pt(C₂2H₄)(pyO)Cl₂] and [Pt(CO)(quinO)Br₂] are reported. The frequency for the νPt-O vibration, ambiguously assigned in the literature, is here assigned unequivocally at 400 cm⁻¹. Previously observed, but inadequately described phenomena are addressed: the νN-O vibration in substituted quinoline N-oxides has been assigned previously at significantly different frequencies, depending on the nature of the substituent. This suggests that there is no specific mid-ir band associated with a high N-O character. A suitable explanation is presented for this phenomenon, showing that in low symmetry systems (eg. quinO) the N-O stretch is dispersed among several modes, whereas in high symmetry systems (eg. pyO) only a few limited modes have a high N-O character. A theoretical study of Cu(I) carbonyl compounds with macrocyclic ligands is presented. Local and global HSAB parameters applied to the donor and Cu atoms are used to explain the observed reactivities and the available spectroscopic data. Extended to [Cu(CO){H₂N(CH₂)[subscript n]NH(CH₂)[subscript m] NH₂}] BPh₄ (where n = 2, m = 2, 3 and n =3, m = 3, 4) and their -d₅ and ¹³CO isotopomers, subtle differences obtained experimentally for the CO stretching frequency in this series have been reproduced in the DFT calculations at the B3LYP level, using the 6-31 G* and 6-31 G** basis sets. Several properties (ligand pK[subscript a] values, νCO frequencies, etc.) correlate with some HSAB descriptors. Vibrational analyses are presented of Cu(I) carbonyl Schiff-base derivatives of N-Benzylidene-N’-[2-(benzyilidene-amino)-ethyl]-ethane-1,2-diamine, {2,2N3(C₆H₄R)₂}, and their -d₅ and ¹³CO isotopomers. The crystal structure of [Cu(CO){2,2N3(C₆H₅)₂}]BPh₄ is reported. From geometry optimizations and the HSAB descriptors, spectroscopic trends ([n]Cu-N and [nu]CO) are related to calculated global hardness and the Hammett substituent parameters, and are discussed in terms of σ-donation and π-backbonding of Cu- CO.
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  • Date Issued: 2005

Mainstreaming Gender Standards in Collective Bargaining

- COSATU

  • Authors: COSATU
  • Date: 2005
  • Subjects: COSATU
  • Language: English
  • Type: text
  • Identifier: http://hdl.handle.net/10962/154231 , vital:39624
  • Description: The apartheid system and capitalism used the patriarchal nature of the South African society through the sexual division of labour and divided the labour force on the grounds of class, race and gender to exploit them for cheap labour to maximize their profits. They exploited the notion of men as the head of the family to force men to become migrant labourers and disregarded the reproductive and domestic role of women.
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  • Date Issued: 2005

Making meaning, making a home: students watching Generations

- O'Shea, Catherine Mary

  • Authors: O'Shea, Catherine Mary
  • Date: 2005
  • Subjects: Generations (Television program) , Students, Black -- South Africa -- Attitudes , Television soap operas -- South Africa , Cross-cultural studies -- South Africa
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: vital:3479 , http://hdl.handle.net/10962/d1002934 , Generations (Television program) , Students, Black -- South Africa -- Attitudes , Television soap operas -- South Africa , Cross-cultural studies -- South Africa
  • Description: This thesis is a reception analysis using qualitative interviews to investigate black students' watching of a South African soap opera, Generations, taking into account the context of a largely white South African university campus. The findings of this study are that students find pleasure in talking about Generations and hold seemingly contradictory views on whether it is 'realistic' or not. The analysis concludes that watching Generations does serve to affirm these students' black identity, since there is a particular need to do so on a campus where black students witness and experience racial discrimination.
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  • Date Issued: 2005

Man doing Ngqokola

- Ngqoko group participants, Composer not specified, Dargie, Dave

Man doing Ngqokola

- Ngqoko group participants, Composer not specified, Dargie, Dave

Marine biotechnology : evaluation and development of methods for the discovery of natural products from fungi

- Pather, Simisha

  • Authors: Pather, Simisha
  • Date: 2005 , 2013-06-18
  • Subjects: Marine biotechnology , Marine fungi -- South Africa , Natural products -- South Africa , Marine plants -- South Africa , Marine metabolites -- South Africa , Cancer -- Treatment , DNA
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:3839 , http://hdl.handle.net/10962/d1007652 , Marine biotechnology , Marine fungi -- South Africa , Natural products -- South Africa , Marine plants -- South Africa , Marine metabolites -- South Africa , Cancer -- Treatment , DNA
  • Description: One of the major impediments in the development of marine natural products is the provision of biologically active natural products in sufficient quantity for complete pharmacological evaluation, clinical trials and eventual commercial production. Marine microorganisms show great promise in providing a renewable source of biologically active natural products. The main aim of this study was to develop and evaluate methods for the isolation, identification and cultivation of marine fungi from the South African marine environment for the production of biologically active secondary metabolites. Twenty-four species of fungi were isolated from marine algae collected from the intertidal zone near Port Alfred, South Africa. The fungi were cultivated in small-scale under static and agitated conditions and their crude intra- and extracellular organic extracts were screened by ¹H NMR and a series of bioassays. Using this as a basis, one isolate was selected for further study. By analyses of the lTS1 region of the ribosomal DNA, the fungal isolate was identified as a marine-derived isolate of Eurotium rubrum (Aspergillus ruber). Although E. rubrum has been isolated from the marine environment, no investigations have been undertaken to determine the adaptation of these isolates to the marine environment. In order to optimise productivity, creativity and incubation time, the fungus was cultivated in small-scale using a variety of carbon (glucose, fructose, lactose, sucrose, marmitol and maltose) and nitrogen sources (ammonium tartrate, urea, peptone and yeast extract). An HPLC-DAD method was developed to assess the metabolic creativity and productivity under different fermentation conditions. Distinctive variations in the range and yield of metabolites produced as well as morphology and growth time were observed. The crude extracts from all fermentations were combined and six known compounds were isolated by reversed-phase chromatography and their structures elucidated by spectroscopic techniques. The known compounds were fIavoglaucin, aspergin, isodihydroauroglaucin, isotetrahydroauroglaucin, neoechinuline A and physcion. Neoechinuline A, isodihydroauroglaucin and isotetrahydroauroglaucin showed activity against oesophageal and cervical cancer cell lines.
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  • Date Issued: 2005

Marine Reserves: a guide to science, design, and use

- Booth, Anthony J

  • Authors: Booth, Anthony J
  • Date: 2005
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/124965 , vital:35714 , https://doi.10.2989/16085910509503862
  • Description: With the considerable pressures that are being placed on our marine resources, there is an urgent need to find alternative strategies to ensure their long-term sustainability. One measure that has been proposed, and which is rapidly gaining popularity, is the designation of Marine Protected Area (MPA). These are demarcated areas that prohibit (or at least restrict) consumptive or extractive uses, such that human interferences and impacts are minimised. In this edited collection of papers, most of which have been written or co-written by the authors themselves, Sobel and Dahlgren have presented an excellent synopsis of the rationale behind, and the scientific basis underpinning, the use of marine reserves as a management tool. In addition, they have devoted half the book to the provision of case studies.
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  • Date Issued: 2005

Masambeni

- Preformer not specified, Composer not specified, Dargie, Dave

Masambeni

- Preformer not specified, Composer not specified, Dargie, Dave

Material characterisation of laser formed dual phase steel components

- Els-Botes, Annelize

  • Authors: Els-Botes, Annelize
  • Date: 2005
  • Subjects: Steel -- Fatigue , Bending , Lasers , Sheet-steel -- Effect of lasers on
  • Language: English
  • Type: Thesis , Doctoral , DTech
  • Identifier: vital:9609 , http://hdl.handle.net/10948/176 , Steel -- Fatigue , Bending , Lasers , Sheet-steel -- Effect of lasers on
  • Description: The nature and scope of this thesis can be divided into four categories: • FORMING PARAMETERS • Identification of various laser forming parameters in order to produce specimens of similar dimension (radius of curvature). • TEMPERATURE AND MICROSTRUCTURE • To study the effect of maximum temperature reached during the forming operation on the microstructure of the various specimens. • FATIGUE LIFE • Compare the fatigue life of the specimens produced by various laser parameters to that of the original material, and also the fatigue life of mechanical formed specimens. • RESIDUAL STRESS PROFILE Determine if the laser forming process induces detrimental residual stress magnitudes in the specimens. The main objective of this thesis was to gain an understanding of the way in which laser forming affects the fatigue performance and residual stress magnitude / distribution of dual phase steel. Although lasers have been used successfully in various manufacturing processes (welding, cutting, marking, etc.), little information is available on the influence of laser forming on many automotive alloys such as dual phase steel. The first part of the work involved a literature review of the process and factors affecting the laser forming process. It became clear from the literature overview that laser forming of sheet material thicker than 1mm is complex in nature. The variables that can influence the process are complicated and their interaction with each other is not easily controlled. The main parameters that were thus controlled in this study are as follows: • Laser power (P) • Laser head travel speed (v) • Laser beam size (mm) The chapters that follow the literature review, deals with the laser forming process of dual phase steel and the production of fatigue specimens using various laser parameters. It was found that the following laser parameters resulted in specimens with approximately the same radius of curvature: Laser power KW Beam diameter mm Interval spacing % Overlap Scanning velocity m/min Line Energy J/m 5 20 10 50 2,5 2000 3,1 14 10,5 25 2 1550 1,5 7,5 7,5 0 1,2 1250 From the results obtained from fatigue testing specimens produced with the above settings, it is clear that the laser forming process has the potential to be employed as a production stage in the manufacture of wheel centre discs while maintaining adequate fatigue strength. Large beam diameters which cause heat penetration through the thickness of the specimen and hence microstructure breakdown should be avoided, since it was shown that these specimens exhibited impaired mechanical properties than those produced with a smaller laser beam diameter. The microstructural changes observed during the forming process needs to be considered since the mechanical properties of the material changes with a change in microstructure. A dramatic change in microstructure was observed; therefore it is of crucial importance that microstructural evaluation plays an important part in deciding optimum laser parameters for the forming process of ferrous alloys. During residual stress analysis, trends were observed between measurements taken at the same location of the samples; regardless whether measurements were taken on the laser irradiated side or the reverse side of the specimen. The only difference was the magnitude of the relieved residual stress. In most cases the obtained relieved residual stress was much smaller in magnitude than that of the original plate (in the bulk of the material). The surface indicated a slight tensile residual stress for most samples evaluated. A good correlation in distribution profile was obtained between microhardness and relieved residual stress distribution at the ‘middle of sample’ location. This indicates that an increase in hardness indicates an increase in residual stress magnitude for the laser formed specimens. In conclusion, this research has proved that it is possible to deform metal plate of a 3,5mm thickness with a CO2 laser system. The research also established the effect of process parameters on the final product’s shape/bend angle and characterised the effect of the laser forming process on the material’s mechanical properties and structural integrity.
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  • Date Issued: 2005

Medicine labels incorporating pictograms: do they influence understanding and adherence?

- Dowse, Roslind, Ehlers, Martina S

  • Authors: Dowse, Roslind , Ehlers, Martina S
  • Date: 2005
  • Language: English
  • Type: Article
  • Identifier: vital:6359 , http://hdl.handle.net/10962/d1006051
  • Description: The objective was to determine the influence of medicine labels incorporating pictograms on the understanding of instructions and on adherence. Eighty-seven Xhosa participants attending an outpatient clinic who had been prescribed a short course of antibiotics were randomly allocated to either a control group (41 participants given text-only labels), or an experimental group (46 participants given text + pictogram labels). All participants had a maximum of 10 years of formal schooling. Follow-up home visits were conducted after 3–5 days to assess understanding of instructions and to evaluate adherence. A high adherence of greater than 90% was found for 54% of the experimental group, compared with only 2% of the control group. Average percentages for understanding in the control and experimental groups were 70 and 95%, respectively, and average adherence was 72 and 90%, respectively. The presence of pictograms was found to contribute positively to both understanding of instructions and adherence.
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  • Date Issued: 2005
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