Chemical constituents and biological studies of Tagetes minuta L. and Rauvolfia caffra Sond
- Authors: Mlala, Sithenkosi
- Date: 2015
- Language: English
- Type: Thesis , Masters , MSc (Organic Chemistry)
- Identifier: vital:11358 , http://hdl.handle.net/10353/d1021325
- Description: Consequently, specific parts or the whole plant can be used for various treatments. The aim of this study was to extract, isolate and characterize the biologically active volatile and non-volatile compounds from Tagetes minuta and Rauvolfia caffra respectively. Tagetes minuta plant was considered for extraction of essential oils using hydrodistillation method. Cis-β-ocimene (38.03%), caryophyllene oxide (18.04%), alloocimene (25.35 %), isopropyl tetradecanoate (17.02 %), cis-ocimene (38.14%) and trans-β-ocimene (37.03%) were the major components of essential oil analyzed from fresh stem, dried stem, fresh leaf, dried leaf, fresh flower and dried flower respectively. The volatile compounds were identified by Gas Chromatography-Mass Spectrometry (GC-MS) and Gas Chromatography (GC). Essential oil of dried stem leaf and flower parts of T. minuta exhibit antioxidant activity as demonstrated by the DPPH and FRAP bioassays. Crude extracts were extracted from R. caffra stem bark using sequence of solvents namely n-hexane, dichloromethane, ethyl acetate, methanol and ethanol. A white powder, a β-sitosterol (non-volatile compound) was isolated by column chromatography from ethyl acetate fractions of R. caffra stem bark and identified on various spectroscopic techniques such as FTIR and (1D and 2D) NMR. Melting point was also determined to be a sharp 129-130 ºC. DCM, EA, MetOH and EtOH fractions as well as β-Sitosterol (compound SM/01), showed antioxidant activity when tested on DPPH, FRAP, total phenolic and flavonoid bioassays. This antioxidant activity might be due to the presence of hydroxyl groups in the compound and crude fractions. On the other hand, T. minuta’s essential oil showed high antioxidant activity when evaluated on the DPPH and FRAP bioassays, which can be attributed to the presence of oxygenated monoterpenes and sesquiterpenes known to act as free radical scavenging and reducing agents. The use of R. caffra stem bark extracts against hypertension and other diseases by traditional healers could be attributed to the presence of phytochemicals (polyphenols and flavonoids) with known health benefits. Thus, it is recommended that the plant should be exploited further using modern techniques involving separation and purification of compounds that can be used for drug formulation. This study supports the use of T. minuta and R. caffra as the potential natural antioxidant source to manage various diseases including hypertension.
- Full Text:
- Date Issued: 2015
- Authors: Mlala, Sithenkosi
- Date: 2015
- Language: English
- Type: Thesis , Masters , MSc (Organic Chemistry)
- Identifier: vital:11358 , http://hdl.handle.net/10353/d1021325
- Description: Consequently, specific parts or the whole plant can be used for various treatments. The aim of this study was to extract, isolate and characterize the biologically active volatile and non-volatile compounds from Tagetes minuta and Rauvolfia caffra respectively. Tagetes minuta plant was considered for extraction of essential oils using hydrodistillation method. Cis-β-ocimene (38.03%), caryophyllene oxide (18.04%), alloocimene (25.35 %), isopropyl tetradecanoate (17.02 %), cis-ocimene (38.14%) and trans-β-ocimene (37.03%) were the major components of essential oil analyzed from fresh stem, dried stem, fresh leaf, dried leaf, fresh flower and dried flower respectively. The volatile compounds were identified by Gas Chromatography-Mass Spectrometry (GC-MS) and Gas Chromatography (GC). Essential oil of dried stem leaf and flower parts of T. minuta exhibit antioxidant activity as demonstrated by the DPPH and FRAP bioassays. Crude extracts were extracted from R. caffra stem bark using sequence of solvents namely n-hexane, dichloromethane, ethyl acetate, methanol and ethanol. A white powder, a β-sitosterol (non-volatile compound) was isolated by column chromatography from ethyl acetate fractions of R. caffra stem bark and identified on various spectroscopic techniques such as FTIR and (1D and 2D) NMR. Melting point was also determined to be a sharp 129-130 ºC. DCM, EA, MetOH and EtOH fractions as well as β-Sitosterol (compound SM/01), showed antioxidant activity when tested on DPPH, FRAP, total phenolic and flavonoid bioassays. This antioxidant activity might be due to the presence of hydroxyl groups in the compound and crude fractions. On the other hand, T. minuta’s essential oil showed high antioxidant activity when evaluated on the DPPH and FRAP bioassays, which can be attributed to the presence of oxygenated monoterpenes and sesquiterpenes known to act as free radical scavenging and reducing agents. The use of R. caffra stem bark extracts against hypertension and other diseases by traditional healers could be attributed to the presence of phytochemicals (polyphenols and flavonoids) with known health benefits. Thus, it is recommended that the plant should be exploited further using modern techniques involving separation and purification of compounds that can be used for drug formulation. This study supports the use of T. minuta and R. caffra as the potential natural antioxidant source to manage various diseases including hypertension.
- Full Text:
- Date Issued: 2015
Experiences of college students, regarding the mentoring role of registered nurses in the public services of the Eastern Cape, South Africa
- Authors: Lundall, Kasthuri
- Date: 2014
- Language: English
- Type: Thesis , Masters , MSc (Nursing Science)
- Identifier: vital:11918 , http://hdl.handle.net/10353/d1016159
- Description: Fifty percent of the learning of student nurses takes place within the clinical learning environment. It is in this environment that nursing students are expected to apply their knowledge, learn new skills, and achieve the required learning outcomes and proficiencies. Nursing program Me s differ significantly, so students ‟practice will vary depending on where they are studying and their practice will develop as the level of proficiency increases, and may also vary depending on the context of placement. Gopee (2008:7) elaborates on the fact that mentoring enables student nurses to gain clinical skills during placements and serves a formal role whereby teaching and practice facilitate professional learning within the healthcare system. The study was undertaken with the aim to describe experiences of college students regarding the mentoring role by registered nurses in the Public Services of the Eastern Cape. The objectives of the study were to explore and describe experiences of college students, regarding the mentoring role of registered nurses in Public Services of the Eastern Cape, to analyse the results and to make suggestions from findings that were obtained. A qualitative, exploratory, descriptive and contextual design was used for this study to explore and describe the experiences of the college students regarding the mentoring role of registered nurses in the Public Services of the Eastern Cape, South Africa. The researcher studied the population of student nurses in the public nursing college in the Eastern Cape at the East London Campus. Purposive sampling which is referred to as a judgmental approach was used. Data were collected by means of focus group interviews. An interview schedule with an unstructured questionnaire was used to investigate and explore information gained from the participants. This study consisted of a total of five focus groups that were recruited from fourth-year nursing students at the East London campus who volunteered to be part of the study. The total number of participants was 31. Data were analysed using v Tesch‟s method of analysis for qualitative research. Two major themes emerged, revealing positive experiences of students with regard to mentoring and negative experiences of students regarding mentoring. After exploring and describing the experiences of college students regarding the mentoring role played by registered nurses in the Public Services of the Eastern Cape, it was concluded that that there is a lack of mentoring, coupled with negativity, by registered nurses which results in many challenges. Recommendations included: Motivation for integration and collaboration; interactive working relationships; introducing a well-established orientation programme; a well-structured clinical teaching programme and procedure manuals; reinstatement of clinical preceptors, clinical objectives and time frames; identify in clinical staff who will mentor student nurses; instituting in-service training programmes and workshops; introduction of peer mentoring; and establishment of set times for routine clinical ward rounds.
- Full Text:
- Date Issued: 2014
- Authors: Lundall, Kasthuri
- Date: 2014
- Language: English
- Type: Thesis , Masters , MSc (Nursing Science)
- Identifier: vital:11918 , http://hdl.handle.net/10353/d1016159
- Description: Fifty percent of the learning of student nurses takes place within the clinical learning environment. It is in this environment that nursing students are expected to apply their knowledge, learn new skills, and achieve the required learning outcomes and proficiencies. Nursing program Me s differ significantly, so students ‟practice will vary depending on where they are studying and their practice will develop as the level of proficiency increases, and may also vary depending on the context of placement. Gopee (2008:7) elaborates on the fact that mentoring enables student nurses to gain clinical skills during placements and serves a formal role whereby teaching and practice facilitate professional learning within the healthcare system. The study was undertaken with the aim to describe experiences of college students regarding the mentoring role by registered nurses in the Public Services of the Eastern Cape. The objectives of the study were to explore and describe experiences of college students, regarding the mentoring role of registered nurses in Public Services of the Eastern Cape, to analyse the results and to make suggestions from findings that were obtained. A qualitative, exploratory, descriptive and contextual design was used for this study to explore and describe the experiences of the college students regarding the mentoring role of registered nurses in the Public Services of the Eastern Cape, South Africa. The researcher studied the population of student nurses in the public nursing college in the Eastern Cape at the East London Campus. Purposive sampling which is referred to as a judgmental approach was used. Data were collected by means of focus group interviews. An interview schedule with an unstructured questionnaire was used to investigate and explore information gained from the participants. This study consisted of a total of five focus groups that were recruited from fourth-year nursing students at the East London campus who volunteered to be part of the study. The total number of participants was 31. Data were analysed using v Tesch‟s method of analysis for qualitative research. Two major themes emerged, revealing positive experiences of students with regard to mentoring and negative experiences of students regarding mentoring. After exploring and describing the experiences of college students regarding the mentoring role played by registered nurses in the Public Services of the Eastern Cape, it was concluded that that there is a lack of mentoring, coupled with negativity, by registered nurses which results in many challenges. Recommendations included: Motivation for integration and collaboration; interactive working relationships; introducing a well-established orientation programme; a well-structured clinical teaching programme and procedure manuals; reinstatement of clinical preceptors, clinical objectives and time frames; identify in clinical staff who will mentor student nurses; instituting in-service training programmes and workshops; introduction of peer mentoring; and establishment of set times for routine clinical ward rounds.
- Full Text:
- Date Issued: 2014
The impact of oil price changes on selected economic indicators in South Africa
- Authors: Vellem, Nomtha
- Date: 2014
- Subjects: Petroleum industry and trade -- South Africa , Foreign exchange rates -- South Africa , Interest rate futures -- South Africa , Economic indicators -- South Africa
- Language: English
- Type: Thesis , Masters , M Com
- Identifier: vital:11485 , http://hdl.handle.net/10353/d1017862 , Petroleum industry and trade -- South Africa , Foreign exchange rates -- South Africa , Interest rate futures -- South Africa , Economic indicators -- South Africa
- Description: The study examines the effect of oil price changes on selected economic indicators in South Africa. A VAR-5 model was applied to quarterly data of 1990:Q1-2012:Q4 estimating the impulse response functions, variance decomposition and Granger-causality tests. The findings allow for a conclusion that oil significantly affects the exchange rate and an inverse link between oil and GDP exists. A unidirectional relation is found where oil Granger-causes the exchange rate and GDP Granger-causes oil in South Africa.
- Full Text:
- Date Issued: 2014
- Authors: Vellem, Nomtha
- Date: 2014
- Subjects: Petroleum industry and trade -- South Africa , Foreign exchange rates -- South Africa , Interest rate futures -- South Africa , Economic indicators -- South Africa
- Language: English
- Type: Thesis , Masters , M Com
- Identifier: vital:11485 , http://hdl.handle.net/10353/d1017862 , Petroleum industry and trade -- South Africa , Foreign exchange rates -- South Africa , Interest rate futures -- South Africa , Economic indicators -- South Africa
- Description: The study examines the effect of oil price changes on selected economic indicators in South Africa. A VAR-5 model was applied to quarterly data of 1990:Q1-2012:Q4 estimating the impulse response functions, variance decomposition and Granger-causality tests. The findings allow for a conclusion that oil significantly affects the exchange rate and an inverse link between oil and GDP exists. A unidirectional relation is found where oil Granger-causes the exchange rate and GDP Granger-causes oil in South Africa.
- Full Text:
- Date Issued: 2014
Testing random walk hypothesis in the stock market prices: evidence from South Africa's stock exchange (2000- 2011)
- Chitenderu, Tafadzwa Thelmah
- Authors: Chitenderu, Tafadzwa Thelmah
- Date: 2013
- Subjects: Johannesburg Stock Exchange , Stock exchanges -- South Africa -- Johannesburg , Random walks (Mathematics)
- Language: English
- Type: Thesis , Masters , M Com
- Identifier: vital:11461 , http://hdl.handle.net/10353/d1006931 , Johannesburg Stock Exchange , Stock exchanges -- South Africa -- Johannesburg , Random walks (Mathematics)
- Description: The Johannesburg Stock Exchange market was tested for the existence of the random walk hypothesis using All Share Index (ALSI) and time series data for the period between 2000 and 2011. The traditionally used methods, the unit root tests and autocorrelation test were employed first and they all confirmed that during the period under consideration, the JSE price index followed the random walk process. In addition, the ARIMA model was built and it was found that the ARIMA ( 1, 1, 1) was the model that best fitted the data in question. Furthermore, residual tests to help determine whether the residuals of the estimated equation show random walk process in the series were done. It was found that the ALSI resembles series that follow random walk hypothesis with strong evidence of RWH indicated in the conducted forecasting tests which showed vast variance between forecasted values and actual indicating little or no forecasting strength in the series. To further validate the findings in this research, the variance ratio test was conducted under heteroscedasticity and it also strongly corroborated that the existence of a random walk process cannot be rejected in the JSE. It was concluded that since the returns follow the random walk hypothesis, it can be said that JSE is efficient in the weak form level of the EMH and therefore opportunities of making excess returns based on out- performing the market is ruled out and is merely a game of chance. In other words, it will be of no use to choose stocks based on information about recent trends in stock prices.
- Full Text:
- Date Issued: 2013
- Authors: Chitenderu, Tafadzwa Thelmah
- Date: 2013
- Subjects: Johannesburg Stock Exchange , Stock exchanges -- South Africa -- Johannesburg , Random walks (Mathematics)
- Language: English
- Type: Thesis , Masters , M Com
- Identifier: vital:11461 , http://hdl.handle.net/10353/d1006931 , Johannesburg Stock Exchange , Stock exchanges -- South Africa -- Johannesburg , Random walks (Mathematics)
- Description: The Johannesburg Stock Exchange market was tested for the existence of the random walk hypothesis using All Share Index (ALSI) and time series data for the period between 2000 and 2011. The traditionally used methods, the unit root tests and autocorrelation test were employed first and they all confirmed that during the period under consideration, the JSE price index followed the random walk process. In addition, the ARIMA model was built and it was found that the ARIMA ( 1, 1, 1) was the model that best fitted the data in question. Furthermore, residual tests to help determine whether the residuals of the estimated equation show random walk process in the series were done. It was found that the ALSI resembles series that follow random walk hypothesis with strong evidence of RWH indicated in the conducted forecasting tests which showed vast variance between forecasted values and actual indicating little or no forecasting strength in the series. To further validate the findings in this research, the variance ratio test was conducted under heteroscedasticity and it also strongly corroborated that the existence of a random walk process cannot be rejected in the JSE. It was concluded that since the returns follow the random walk hypothesis, it can be said that JSE is efficient in the weak form level of the EMH and therefore opportunities of making excess returns based on out- performing the market is ruled out and is merely a game of chance. In other words, it will be of no use to choose stocks based on information about recent trends in stock prices.
- Full Text:
- Date Issued: 2013
A study on the knowledge and skills of police officers in handling mentally ill persons in Mdantsane in the Eastern Cape Province of South Africa
- Authors: Kolwapi, Xola Xolani
- Date: 2009
- Subjects: Mentally ill -- South Africa -- Eastern Cape , Police -- South Africa -- Eastern Cape , People with disabilities -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc (Nursing Science)
- Identifier: vital:11902 , http://hdl.handle.net/10353/406 , Mentally ill -- South Africa -- Eastern Cape , Police -- South Africa -- Eastern Cape , People with disabilities -- South Africa -- Eastern Cape
- Description: The dissertation argues that police officers are not trained in handling mentally ill persons. Purpose The study explored police officers‟ knowledge of mental illness and skills necessary for handling mentally ill people. Research methods The descriptive quantitative investigation has been used as a research strategy to identify the knowledge and skills of police officers in handling mentally ill persons. Forty five police officers were randomly selected from a population of 136 police officers. A self administered questionnaire was used for collecting data. Data analysis was done manually and frequency distributions, cross-tabulations and correlations were carried out. Results The findings revealed that police officers do not have knowledge and skills to handle mentally ill people. Recommendations It is recommended that mental health care practitioners should engage the police in discussions on training in handling mentally ill people. iv Limitations Due to time and budgetary limitations, the study had to settle for a more modest investigation
- Full Text:
- Date Issued: 2009
- Authors: Kolwapi, Xola Xolani
- Date: 2009
- Subjects: Mentally ill -- South Africa -- Eastern Cape , Police -- South Africa -- Eastern Cape , People with disabilities -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc (Nursing Science)
- Identifier: vital:11902 , http://hdl.handle.net/10353/406 , Mentally ill -- South Africa -- Eastern Cape , Police -- South Africa -- Eastern Cape , People with disabilities -- South Africa -- Eastern Cape
- Description: The dissertation argues that police officers are not trained in handling mentally ill persons. Purpose The study explored police officers‟ knowledge of mental illness and skills necessary for handling mentally ill people. Research methods The descriptive quantitative investigation has been used as a research strategy to identify the knowledge and skills of police officers in handling mentally ill persons. Forty five police officers were randomly selected from a population of 136 police officers. A self administered questionnaire was used for collecting data. Data analysis was done manually and frequency distributions, cross-tabulations and correlations were carried out. Results The findings revealed that police officers do not have knowledge and skills to handle mentally ill people. Recommendations It is recommended that mental health care practitioners should engage the police in discussions on training in handling mentally ill people. iv Limitations Due to time and budgetary limitations, the study had to settle for a more modest investigation
- Full Text:
- Date Issued: 2009
Community participation in solid waste management in high-density low-income areas: the case of C-Section in Duncan Village
- Authors: Mazinyo, Sonwabo Perez
- Date: 2009
- Subjects: Refuse and refuse disposal -- South Africa -- Eastern Cape , Sewage disposal -- South Africa -- Eastern Cape , Low-income housing -- South Africa -- Eastern Cape , Social participation -- South Africa -- Eastern Cape , Conflict management -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MPhil (Environmental Studies)
- Identifier: vital:11875 , http://hdl.handle.net/10353/261 , Refuse and refuse disposal -- South Africa -- Eastern Cape , Sewage disposal -- South Africa -- Eastern Cape , Low-income housing -- South Africa -- Eastern Cape , Social participation -- South Africa -- Eastern Cape , Conflict management -- South Africa -- Eastern Cape
- Description: Solid waste management in high density low-income areas is a problem that manifests itself in ubiquitous illegal dumpsites and unhealthy living environmental conditions. Community participation in solid waste management in Duncan Village, C-Section has been found to be part of the solution to this problem. This study investigates community participation in SWM at household level, community waste project level and at informal salvaging/scavenging level. The integration of community participation into existing Buffalo City Municipality waste management plans and the nature of the relationship between the different interest groups are investigated. This study employs qualitative research methods where interviews and participatory observations are used to investigate key objectives. The nature of the relationships between councillors, C-Section residents and the Buffalo City Municipality Departments are tenuous and fraught with conflicts. These conflicts emerge due to the lack of communication as well as due to the non-integration of the community interest groups‟ views and activities into solid waste management in C-Section. The study suggests that this lack of communication should be addressed and that integrated participation of all stakeholders must be encouraged for effective solid waste management in a high density low-income community.
- Full Text:
- Date Issued: 2009
- Authors: Mazinyo, Sonwabo Perez
- Date: 2009
- Subjects: Refuse and refuse disposal -- South Africa -- Eastern Cape , Sewage disposal -- South Africa -- Eastern Cape , Low-income housing -- South Africa -- Eastern Cape , Social participation -- South Africa -- Eastern Cape , Conflict management -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MPhil (Environmental Studies)
- Identifier: vital:11875 , http://hdl.handle.net/10353/261 , Refuse and refuse disposal -- South Africa -- Eastern Cape , Sewage disposal -- South Africa -- Eastern Cape , Low-income housing -- South Africa -- Eastern Cape , Social participation -- South Africa -- Eastern Cape , Conflict management -- South Africa -- Eastern Cape
- Description: Solid waste management in high density low-income areas is a problem that manifests itself in ubiquitous illegal dumpsites and unhealthy living environmental conditions. Community participation in solid waste management in Duncan Village, C-Section has been found to be part of the solution to this problem. This study investigates community participation in SWM at household level, community waste project level and at informal salvaging/scavenging level. The integration of community participation into existing Buffalo City Municipality waste management plans and the nature of the relationship between the different interest groups are investigated. This study employs qualitative research methods where interviews and participatory observations are used to investigate key objectives. The nature of the relationships between councillors, C-Section residents and the Buffalo City Municipality Departments are tenuous and fraught with conflicts. These conflicts emerge due to the lack of communication as well as due to the non-integration of the community interest groups‟ views and activities into solid waste management in C-Section. The study suggests that this lack of communication should be addressed and that integrated participation of all stakeholders must be encouraged for effective solid waste management in a high density low-income community.
- Full Text:
- Date Issued: 2009
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