Assessment of antibacterial potentials of Garcinia Kola seed extracts and their interactions with antibiotics
- Authors: Sibanda, Thulani
- Date: 2007
- Subjects: Drug resistance in microorganisms , Garcinia , Antibiotics
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/19236 , vital:43038
- Description: The antibacterial potency of the extracts of the seed of Garcinia kola (bitter kola) was investigated in this study against a panel of referenced, environmental and clinical bacterial strains. The killing rates of the active extract as well as their potential for combination antibacterial therapy with standard antibiotics were also elucidated using standard procedures. The aqueous and acetone extracts of the seed were screened for activity against 27 bacterial isolates. The aqueous extract exhibited activity mainly against Gram positive organisms with Minimum inhibitory concentration (MIC) values ranging from 5 mgml-1 – 20 mgml-1, while the acetone extract showed activity against both Gram negative and Gram positive organisms with MIC values ranging from 10 mgml-1 - 0.156 mgml-1. The acetone extract also showed rapid bactericidal activity against Staphylococcus aureus ATCC 6538 with a 3.097 Log10 reduction in counts within 4 hours at 0.3125 mgml-1 and a 1.582 Log10 reduction against Proteus vulgaris CSIR 0030 at 5 mgml-1 after 1 hour. In addition, the aqueous, methanol and acetone extracts of the seeds also exhibited activity against four clinical strains of Staphylococcus isolated from wound sepsis specimens. The MIC values for the aqueous extract were 10 mgml-1 for all the isolates while the acetone and methanol extracts had lower values ranging from 0.3125 - 0.625 mgml-1. The acetone extract was strongly bactericidal against Staphylococcus aureus OKOH3 resulting in a 2.70 Log10 reduction in counts at 1.25 mgml-1 within 4 hours of exposure and a complete elimination of the organism after 8 hours. The bactericidal activity of the same extract against Staphylococcus aureus OKOH1 was weak, achieving only a 2.92 Log10 reduction in counts at 1.25 mgml-1 (4× MIC) in 24 hours. In the test for interactions between the acetone extract of the seeds and antibiotics, synergistic interactions were observed largely against Gram positive organisms using the FIC indices, (indices of 0.52 - 0.875) with combinations against Gram negatives yielding largely antagonistic interactions (indices of 2.0 to 5.0). Synergy (≥ 1000 times or ≥ 3 Log10 potentiation of the bactericidal activity) against both Gram negative and Gram positive organisms was detected by time kill assays mainly involving the antibiotics tetracycline, chloramphenicol, amoxycillin and penicillin G. Combinations involving erythromycin and ciprofloxacin consistently gave antagonistic or indifferent interactions. We conclude that the acetone extract of Garcinia kola seeds possess strong bactericidal activities against both Gram positive and Gram negative organisms and can be therapeutically useful in the treatment of bacterial infections including the problematic staphylococcal wound infections. In addition, the acetone extract can be a potential source of broad spectrum resistance modifying compounds that can potentially improve the performance of antibiotics in the treatment of drug resistant infections. , Thesis (MSc)-- Microbiology, University of Fort Hare, 2007
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- Date Issued: 2007
Composition portfolio
- Authors: Moss, Keith
- Date: 2007
- Subjects: Uncatalogued
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10962/193724 , vital:45390
- Description: Whitacre's music is primarily diatonic with subtle modulations, where the new key is always preserved diatonicaliy as well. I refer to this style as expanded diatonicism. Examples in my work of expanded diatonicism within this portfolio are to be found in navem ad somnium, Wynken, Blynken and Nod, as well as Hymn for Brass. My applications of expanded diatonic practices within each of these works are discussed in a separate appendix within the body of this portfolio. That these works are vocal or have a vocal inspiration (Hymn for Brass) reveals the extent of my initial reaction to Whitacre's music during a choral rehearsal. Furthermore, in my vocal compositions especially I chose texts which frequently gravitate towards ideas related to water, the ocean and ships. Whilst water has a soothing and inspiring influence upon me, presumably evidenced in my expanded diatonicism, it also represents my journey and investigation into the sound work of Whitacre in particular. It may be noticed that many of my works in this portfolio have religious orientated themes. I am a Christian, and belong to a Berean 2 Congregational Church. Whilst I am not Catholic or Anglican, I nonetheless have made use of texts from the liturgy of these denominations, as they emphasise the basis of my Christian faith. Why I chose Hymn for Brass as a title could possibly be construed as a religious reference, however it was named after the piece was written, and had no theological connotations in its inception save for the hymnody style of the orchestration. Providence and The Eventide both have a Christian philosophical foundation which is explored in depth in the accompanying appendix. The latter work explores an extension of my expanded diatonic style through incorporating aspects of chromaticism. The rationale for this is dealt with in my discussion of this work. This portfolio represents an overview of my compositional activities to date and displays my growing confidence with the technical aspects of composition as well as my yearning for experimentation with new ideas and manners of expression. , Thesis (MMus) -- Faculty of Humanities, Music and Musicology, 2007
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- Date Issued: 2007
The relevance of sustainable development principles and goals through a case study of Gold Fields and Living Gold
- Authors: Ferreira, Adrian
- Date: 2007
- Subjects: Uncatalogued
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10962/192977 , vital:45286
- Description: The conventional definition of sustainable development as proposed by the Brundtland Report (United Nations, 1987), involving the integration of economic, social and environmental components, is widely accepted. Presumed benefits of these current framework applications tend to perpetuate a business as usual status, with no real sustainable development occurring. The growing debate surrounding this topic makes the case for relevant and contextual inputs to be included into sustainable development objectives. A case study, of Gold Fields and Living Gold, attempts to create a deeper understanding of the components of this debate, and begins to contextualise sustainable development principles, goals and their outcomes. This is carried out though an enquiry of the use of cultural development as a fourth sustainable development category. The case study includes the opinions of a directly affected local community entity (Living Gold) in order to observe the difference between the two organisations (Gold Fields and Living Gold). During the study, the focus began to move away from purely unabated growth impacts and looked to the creation and fostering of resilience and flexibility by the use of adaptive management. In breeding states of resilience, it was recognised that cultural impacts played an important role in ensuring long term systemic resilience. The case study involved assessing the feedback and responses of strategically selected individuals at both organisations, with Gold Fields representing a more western centric entity and Living Gold a formal representation of a traditional/ indigenous community. Similarities and differences were assessed in order to understand how current sustainable development criteria might differ between organisations that have different end objectives in mind, yet are dependent on each other. The findings resulted in a perspective of how culture could be used to describe the qualities of a local community, and how to begin aligning development goals with affected communities. The result was the development of the Integrated Resilience Sustainability Method and the consequent development of the Balanced Bottom Line Framework, which seeks to promote sustainable development along the lines of economic, social, environmental and cultural development. , Thesis (MBA) -- Faculty of Commerce, Rhodes Investec Business School, 2007
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- Date Issued: 2007