The development of a personal philosophy and practice of servant leadership : a grounded theory study
- Authors: Taylor, Simon Michael
- Date: 2014
- Subjects: Hilton College (Pietermaritzburg, South Africa) , Servant leadership , Grounded theory , Community and school -- South Africa -- KwaZulu-Natal , Student volunteers in social service -- South Africa -- KwaZulu-Natal , Educational leadership -- South Africa -- KwaZulu-Natal
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:1199 , http://hdl.handle.net/10962/d1012986
- Description: The purpose of this study is to develop a substantive grounded theory explaining the development of a philosophy and the practice of leadership amongst young adults who had attended Hilton College and whom were exposed to their servant leadership development programme. The grounded theory method in this study was developed using conventions identified by Strauss and Corbin (1990) and relying upon a collection of incidents noted during interviews with former students, teachers, housemasters, headmaster and Hiltonian Society board members. In total thirty-six interviews were conducted over a period of four years in South Africa, the United Kingdom and Kenya. Using the grounded theory methodology, an understanding of the theoretical model emerged through the development of a personal philosophy and the practice of servant leadership. Related to the central phenomenon of individual leadership philosophy and practice, the causal condition of opportunity to lead, influenced how the individual philosophy and practice emerged. Strategies used by the participants to nurture their philosophy and practice of leadership were the leadership development programme, community service, feedback and reflection. The data identified the intervening conditions and conditions relating to the context of the leadership philosophy and practice. The consequences of developing a leadership philosophy and practice were related to leadership behaviour; self-esteem; growth; follower relations; empowering of others; and relationship to institutions. The theoretical model illustrated the holistic nature of an individual’s leadership philosophy and practice. In this instance, the nature of the data revealed that the individual's leadership philosophy and practice that developed amongst the participants was predominately servant leadership. The different approaches to leadership development were scrutinised with the intention of locating the grounded theory that developed in this study, within the available literature. The literature did provide some useful insights, in particular the social field theory of Bourdieu (1998), which offered a more encompassing explanation and showed much promise in providing an understanding of leadership development. Wheatley's (1999) interpretation of field theory further explained the influence of servant leadership in leadership development. Finally, the researcher developed a set of propositions and recommendations for practice and future research and discussed the value of this research.
- Full Text:
- Date Issued: 2014
- Authors: Taylor, Simon Michael
- Date: 2014
- Subjects: Hilton College (Pietermaritzburg, South Africa) , Servant leadership , Grounded theory , Community and school -- South Africa -- KwaZulu-Natal , Student volunteers in social service -- South Africa -- KwaZulu-Natal , Educational leadership -- South Africa -- KwaZulu-Natal
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:1199 , http://hdl.handle.net/10962/d1012986
- Description: The purpose of this study is to develop a substantive grounded theory explaining the development of a philosophy and the practice of leadership amongst young adults who had attended Hilton College and whom were exposed to their servant leadership development programme. The grounded theory method in this study was developed using conventions identified by Strauss and Corbin (1990) and relying upon a collection of incidents noted during interviews with former students, teachers, housemasters, headmaster and Hiltonian Society board members. In total thirty-six interviews were conducted over a period of four years in South Africa, the United Kingdom and Kenya. Using the grounded theory methodology, an understanding of the theoretical model emerged through the development of a personal philosophy and the practice of servant leadership. Related to the central phenomenon of individual leadership philosophy and practice, the causal condition of opportunity to lead, influenced how the individual philosophy and practice emerged. Strategies used by the participants to nurture their philosophy and practice of leadership were the leadership development programme, community service, feedback and reflection. The data identified the intervening conditions and conditions relating to the context of the leadership philosophy and practice. The consequences of developing a leadership philosophy and practice were related to leadership behaviour; self-esteem; growth; follower relations; empowering of others; and relationship to institutions. The theoretical model illustrated the holistic nature of an individual’s leadership philosophy and practice. In this instance, the nature of the data revealed that the individual's leadership philosophy and practice that developed amongst the participants was predominately servant leadership. The different approaches to leadership development were scrutinised with the intention of locating the grounded theory that developed in this study, within the available literature. The literature did provide some useful insights, in particular the social field theory of Bourdieu (1998), which offered a more encompassing explanation and showed much promise in providing an understanding of leadership development. Wheatley's (1999) interpretation of field theory further explained the influence of servant leadership in leadership development. Finally, the researcher developed a set of propositions and recommendations for practice and future research and discussed the value of this research.
- Full Text:
- Date Issued: 2014
An investigation into the role of Xhosa male initiation in moral regeneration
- Authors: Ntombana, Luvuyo
- Date: 2011
- Subjects: Xhosa (African people) -- Rites and ceremonies , Initiation rites
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: vital:16132 , http://hdl.handle.net/10948/d1006265 , Xhosa (African people) -- Rites and ceremonies , Initiation rites
- Description: This research study in Mdantsane (East London), Whittlesea (Hewu), Njiveni (Libode) and Cala sought to investigate the role of the amaXhosa male initiation in moral regeneration focusing on socio-cultural, educational and religious aspects related to moral values. The role of the amaXhosa male initiation as a rite of passage from boyhood to manhood, how it was viewed in the past, its impact upon the initiates and its contribution to the moral upholding of values were investigated. It was further intended to establish whether westernisation and urbanisation brought a shift of meaning and emphasis to the current initiation practice and, if so, to what extent has the ceremony departed from traditional norms and what challenges the ceremony has to face at present. A qualitative research method involving an ethnographic study was utilised, which includes in-depth, semi-structured interviews (formal interviews and informal discussions) and participant observation. Research findings suggested that in the past the amaXhosa male initiation played a role in the instruction of moral values. However, this study identified a shift of meaning in the practice which has been more evident in urban than in rural areas. The shift suggested that the instruction role has changed in prominence and there is less emphasis on teaching and appropriate adult behaviour. Moreover that the amakhankatha, who had the major role in teaching of the initiates are now participating in making the role less effective and sometimes introducing influences that are destructive to the initiates. Such negative influences include abuse of alcohol and drugs, promiscuity among the youth and disobedience of elders. It is argued that revisiting the teachings surrounding male initiation may cultivate productive debates on how young males are taught morality in today's society. Furthermore, that if the Xhosa male initiation could be contextualised it can play a role in the instruction of boys as they graduate to manhood and that can contribute to moral regeneration in South Africa.
- Full Text:
- Date Issued: 2011
- Authors: Ntombana, Luvuyo
- Date: 2011
- Subjects: Xhosa (African people) -- Rites and ceremonies , Initiation rites
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: vital:16132 , http://hdl.handle.net/10948/d1006265 , Xhosa (African people) -- Rites and ceremonies , Initiation rites
- Description: This research study in Mdantsane (East London), Whittlesea (Hewu), Njiveni (Libode) and Cala sought to investigate the role of the amaXhosa male initiation in moral regeneration focusing on socio-cultural, educational and religious aspects related to moral values. The role of the amaXhosa male initiation as a rite of passage from boyhood to manhood, how it was viewed in the past, its impact upon the initiates and its contribution to the moral upholding of values were investigated. It was further intended to establish whether westernisation and urbanisation brought a shift of meaning and emphasis to the current initiation practice and, if so, to what extent has the ceremony departed from traditional norms and what challenges the ceremony has to face at present. A qualitative research method involving an ethnographic study was utilised, which includes in-depth, semi-structured interviews (formal interviews and informal discussions) and participant observation. Research findings suggested that in the past the amaXhosa male initiation played a role in the instruction of moral values. However, this study identified a shift of meaning in the practice which has been more evident in urban than in rural areas. The shift suggested that the instruction role has changed in prominence and there is less emphasis on teaching and appropriate adult behaviour. Moreover that the amakhankatha, who had the major role in teaching of the initiates are now participating in making the role less effective and sometimes introducing influences that are destructive to the initiates. Such negative influences include abuse of alcohol and drugs, promiscuity among the youth and disobedience of elders. It is argued that revisiting the teachings surrounding male initiation may cultivate productive debates on how young males are taught morality in today's society. Furthermore, that if the Xhosa male initiation could be contextualised it can play a role in the instruction of boys as they graduate to manhood and that can contribute to moral regeneration in South Africa.
- Full Text:
- Date Issued: 2011
Psigobiografiese persoonlikheidsbeskrywing van Generaal Christiaan de Wet
- Authors: Henning, Riana
- Date: 2010
- Subjects: De Wet, Christiaan Rudolf, 1854-1922 Psychology -- Biographical methods Psychoanalysis Big Five model Politicians -- Psychology South Africa -- Politics and government -- 1836-1909 South Africa -- Politics and government -- 1909-1948
- Language: Afrikaans
- Type: Thesis , Doctoral , PhD
- Identifier: vital:2990 , http://hdl.handle.net/10962/d1002499
- Description: Hierdie is 'n psigobiografiese studie van Generaal Christiaan Rudolph de Wet. 'n Psigobiografiese studie is die bestudering van 'n persoon se volledige lewe met die doel om die persoon beter te verstaan. Psigobiografiese navorsing maak gebruik van psigologiese teorieë wat aangewend word om die biografiese data van 'n persoon se lewe te beskryf en moontlik ook te verklaar. Die individu wat bestudeer word, is gewoonlik 'n bekende, invloedryke, navolgenswaardige, interessante of modelfiguur. Daar is tans 'n oplewing in die veld van psigobiografiese studies, maar daar word nog steeds nie genoeg in die akademiese veld gedoen om psigobiografiese studies te bevorder nie. De Wet (1854-1922) is vir hierdie studie gekies omdat hy 'n interessante, dog komplekse figuur was. Hy het veral tydens die Anglo-Boereoorlog in 1899-1902 bekendheid verwerf. As 45-jarige man het De Wet in die Anglo-Boereoorlog geveg en vinnig opgang as 'n militêre leier gemaak. Sy vindingryke ontsnappingspogings het die Britse magte hoofbrekens besorg. Wat De Wet verder uniek maak, is dat hy met net drie maande skoolopleiding in die parlement gedien het, as president verkies is, die hoogste gesag in die Verdedigingsmag gehad het en 'n boek oor sy oorlogsherinneringe geskryf het. Alhoewel daar akademiese werke oor De Wet bestaan, is daar tot op hede nog geen psigobiografiese studie oor hom gedoen nie. Die doel van die studie was om die mens agter die legende na vore te bring. Daar is ook gepoog om moontlike antwoorde en verklarings op onbeantwoorde vrae te gee. Die studie het van beide kwalitatiewe en kwantitatiewe data gebruik gemaak en kan as 'n psigobiografiese gevalstudie beskryf word. Die Vyf-faktor model van Costa en McCrae (1992) is op die biografiese data van De Wet toegepas om sodoende sy persoonlikheidseienskappe te beskryf. Die bevindinge het interessante persoonlikheidseienskappe van De Wet deur middel van die Vyf-faktor model aan die lig gebring. Volgens die kwalitatiewe navorsingsbevindinge was De Wet 'n vyandige, aksie-gedrewe, bevoegde, prestasie-strewende, selfgedissiplineerde, warm, openhartige, saggeaarde en beskeie persoon. Die kwalitatiewe en kwantitatiewe data-ontledings het uiteenlopende persoonlikheidskenmerke by De Wet geïdentifiseer. Die grootste verskille het by die fasette warmte, openhartigheid en altruïsme voorgekom. Die waarde van die studie is dat 'n wetenskaplike persoonlikheidsontleding van De Wet gedoen is. Dit is ook die eerste studie waar 'n teoretiese model op De Wet se persoonlikheid toegepas is. Alhoewel die studie sekere tekortkominge toon, beklemtoon dit terselfdertyd die wenslikheid daarvan om alternatiewe modelle te gebruik tydens die ontleding van persoonlikheidskenmerke. Die studie dui ook op die behoefte aan verdere navorsing, byvoorbeeld soortgelyke ontledings en vergelykings van die persoonlikhede van ander militêre bevelvoerders (De la Rey, Smuts, Beyers, Hertzog).
- Full Text:
- Date Issued: 2010
- Authors: Henning, Riana
- Date: 2010
- Subjects: De Wet, Christiaan Rudolf, 1854-1922 Psychology -- Biographical methods Psychoanalysis Big Five model Politicians -- Psychology South Africa -- Politics and government -- 1836-1909 South Africa -- Politics and government -- 1909-1948
- Language: Afrikaans
- Type: Thesis , Doctoral , PhD
- Identifier: vital:2990 , http://hdl.handle.net/10962/d1002499
- Description: Hierdie is 'n psigobiografiese studie van Generaal Christiaan Rudolph de Wet. 'n Psigobiografiese studie is die bestudering van 'n persoon se volledige lewe met die doel om die persoon beter te verstaan. Psigobiografiese navorsing maak gebruik van psigologiese teorieë wat aangewend word om die biografiese data van 'n persoon se lewe te beskryf en moontlik ook te verklaar. Die individu wat bestudeer word, is gewoonlik 'n bekende, invloedryke, navolgenswaardige, interessante of modelfiguur. Daar is tans 'n oplewing in die veld van psigobiografiese studies, maar daar word nog steeds nie genoeg in die akademiese veld gedoen om psigobiografiese studies te bevorder nie. De Wet (1854-1922) is vir hierdie studie gekies omdat hy 'n interessante, dog komplekse figuur was. Hy het veral tydens die Anglo-Boereoorlog in 1899-1902 bekendheid verwerf. As 45-jarige man het De Wet in die Anglo-Boereoorlog geveg en vinnig opgang as 'n militêre leier gemaak. Sy vindingryke ontsnappingspogings het die Britse magte hoofbrekens besorg. Wat De Wet verder uniek maak, is dat hy met net drie maande skoolopleiding in die parlement gedien het, as president verkies is, die hoogste gesag in die Verdedigingsmag gehad het en 'n boek oor sy oorlogsherinneringe geskryf het. Alhoewel daar akademiese werke oor De Wet bestaan, is daar tot op hede nog geen psigobiografiese studie oor hom gedoen nie. Die doel van die studie was om die mens agter die legende na vore te bring. Daar is ook gepoog om moontlike antwoorde en verklarings op onbeantwoorde vrae te gee. Die studie het van beide kwalitatiewe en kwantitatiewe data gebruik gemaak en kan as 'n psigobiografiese gevalstudie beskryf word. Die Vyf-faktor model van Costa en McCrae (1992) is op die biografiese data van De Wet toegepas om sodoende sy persoonlikheidseienskappe te beskryf. Die bevindinge het interessante persoonlikheidseienskappe van De Wet deur middel van die Vyf-faktor model aan die lig gebring. Volgens die kwalitatiewe navorsingsbevindinge was De Wet 'n vyandige, aksie-gedrewe, bevoegde, prestasie-strewende, selfgedissiplineerde, warm, openhartige, saggeaarde en beskeie persoon. Die kwalitatiewe en kwantitatiewe data-ontledings het uiteenlopende persoonlikheidskenmerke by De Wet geïdentifiseer. Die grootste verskille het by die fasette warmte, openhartigheid en altruïsme voorgekom. Die waarde van die studie is dat 'n wetenskaplike persoonlikheidsontleding van De Wet gedoen is. Dit is ook die eerste studie waar 'n teoretiese model op De Wet se persoonlikheid toegepas is. Alhoewel die studie sekere tekortkominge toon, beklemtoon dit terselfdertyd die wenslikheid daarvan om alternatiewe modelle te gebruik tydens die ontleding van persoonlikheidskenmerke. Die studie dui ook op die behoefte aan verdere navorsing, byvoorbeeld soortgelyke ontledings en vergelykings van die persoonlikhede van ander militêre bevelvoerders (De la Rey, Smuts, Beyers, Hertzog).
- Full Text:
- Date Issued: 2010
The role of salinity as an abiotic driver of ecological condition in a rural agricultural catchment
- Authors: Lerotholi, Sekhonyana
- Date: 2006
- Subjects: Soils, Salts in -- South Africa -- Kat River , Water salinization -- South Africa -- Kat River , Water quality -- South Africa -- Kat River , Salinization -- Control -- South Africa -- Kat River , Agricultural pollution -- South Africa -- Kat River , Aquatic ecology -- South Africa -- Kat River , Salinity -- South Africa -- Kat River
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4852 , http://hdl.handle.net/10962/d1005528 , Soils, Salts in -- South Africa -- Kat River , Water salinization -- South Africa -- Kat River , Water quality -- South Africa -- Kat River , Salinization -- Control -- South Africa -- Kat River , Agricultural pollution -- South Africa -- Kat River , Aquatic ecology -- South Africa -- Kat River , Salinity -- South Africa -- Kat River
- Description: The Kat River is an agricultural catchment that drains salt rich geology. Potential salinity impacts on ecological condition of the river were investigated. Monthly salt concentrations and flow discharges were monitored at ten sites along the Kat River below the Kat Dam. Monthly salt loads were computed to relate salinity to land use and ionic data used to assess the toxicity of major salts using the TIMS model. Concentration duration curves for sodium chloride were derived from flow concentration relationships, representing sodium chloride concentrations to which the aquatic ecosystem had been exposed. The ecological condition was assessed at nineteen sites using SASS5 biotic index over four seasons. Finally, the modelled instream salt concentrations and bioasessments were evaluated in terms of the modelled level of species protection afforded at different salt concentrations. Species Sensitivity Distributions (SSDs) were used for this exercise. There was a general downstream increase in salinity with the minimum concentrations recorded at the Fairbain tributary (84 mg/L) and maximum levels at the sewage outfall in Fort Beaufort (1222 mg/L). There was evidence that citrus irrigation upstream of Fort Beaufort increased salinisation. Sodium chloride, and to a lesser extent magnesium sulphate, were the dominant salts in the Kat River catchment, with the latter being more toxic. However these had little or no impact on the aquatic ecosystem. Flow-derived sodium chloride concentrations showed that both the Balfour and Blinkwater tributaries were in a fair/ poor condition. However with regard to ecological condition, it was demonstrated that the river is generally in a good state except for the Blinkwater River and the lower catchment. Degraded habitat condition at the Blinkwater was responsible for poor ecological condition. Integrating SSD derived classes, sodium chloride classes and ecological condition indicated that sodium chloride is a driver of ecological condition at the sewage treatment works and the subsequent site (only two of nineteen biomonitoring sites).
- Full Text:
- Date Issued: 2006
- Authors: Lerotholi, Sekhonyana
- Date: 2006
- Subjects: Soils, Salts in -- South Africa -- Kat River , Water salinization -- South Africa -- Kat River , Water quality -- South Africa -- Kat River , Salinization -- Control -- South Africa -- Kat River , Agricultural pollution -- South Africa -- Kat River , Aquatic ecology -- South Africa -- Kat River , Salinity -- South Africa -- Kat River
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4852 , http://hdl.handle.net/10962/d1005528 , Soils, Salts in -- South Africa -- Kat River , Water salinization -- South Africa -- Kat River , Water quality -- South Africa -- Kat River , Salinization -- Control -- South Africa -- Kat River , Agricultural pollution -- South Africa -- Kat River , Aquatic ecology -- South Africa -- Kat River , Salinity -- South Africa -- Kat River
- Description: The Kat River is an agricultural catchment that drains salt rich geology. Potential salinity impacts on ecological condition of the river were investigated. Monthly salt concentrations and flow discharges were monitored at ten sites along the Kat River below the Kat Dam. Monthly salt loads were computed to relate salinity to land use and ionic data used to assess the toxicity of major salts using the TIMS model. Concentration duration curves for sodium chloride were derived from flow concentration relationships, representing sodium chloride concentrations to which the aquatic ecosystem had been exposed. The ecological condition was assessed at nineteen sites using SASS5 biotic index over four seasons. Finally, the modelled instream salt concentrations and bioasessments were evaluated in terms of the modelled level of species protection afforded at different salt concentrations. Species Sensitivity Distributions (SSDs) were used for this exercise. There was a general downstream increase in salinity with the minimum concentrations recorded at the Fairbain tributary (84 mg/L) and maximum levels at the sewage outfall in Fort Beaufort (1222 mg/L). There was evidence that citrus irrigation upstream of Fort Beaufort increased salinisation. Sodium chloride, and to a lesser extent magnesium sulphate, were the dominant salts in the Kat River catchment, with the latter being more toxic. However these had little or no impact on the aquatic ecosystem. Flow-derived sodium chloride concentrations showed that both the Balfour and Blinkwater tributaries were in a fair/ poor condition. However with regard to ecological condition, it was demonstrated that the river is generally in a good state except for the Blinkwater River and the lower catchment. Degraded habitat condition at the Blinkwater was responsible for poor ecological condition. Integrating SSD derived classes, sodium chloride classes and ecological condition indicated that sodium chloride is a driver of ecological condition at the sewage treatment works and the subsequent site (only two of nineteen biomonitoring sites).
- Full Text:
- Date Issued: 2006
The microbial production of polyphenol oxidase enzyme systems and their application in the treatment of phenolic wastewaters
- Authors: Goetsch, Patricia-Ann
- Date: 1993
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:21060 , http://hdl.handle.net/10962/6190
- Description: Phenolic compounds are a group of organic chemicals present in the wastewaters of many synthetic industrial processes. Due to their extreme toxicity to man and animals, and deleterious impact on the environment, a range of techniques exist for the effective treatment and disposal of these pollutants. Biological degradation using microbial enzymes presents a valuable alternative to conventional wastewater treatment systems. This research was therefore initiated to investigate the polyphenol oxidase enzyme system and the feasibility of its application for effluent treatment and studies in organic solvents. The enzyme system is widely distributed in nature, with Agaricus bisporus (the common mushroom) being the best known producer. Biochemical investigations of the enzyme system were therefore carried out using this extract. A screening programme was initiated to identify microbial polyphenol oxidase producers which could be cultured in liquid media, thereby enabling the production of large quantities of enzyme in fermentation systems. Extensive growth optimization and enzyme induction and optimization studies were carried out on selected cultures. A number of good producers were isolated, namely a bacterial culture designated AECI culture no. 26, Streptomyces antibioticus, Streptomyces glaucescens and a manipulated strain, Streptomyces lividans (pIJ702). Enzyme production by Agaricus bisporus mycelia was optimized in deep-liquid culture; enzyme extracts showed high phenol removal efficiencies. Streptomyces antibioticus, Streptomyces glaucescens, Streptomyces lividans (pIJ702) and AECI culture no. 26 whole cells were also investigated for phenol-removing ability in simulated phenolic effluents. The use of whole cells reduces enzyme inactivation and instability due to the protection of the enzyme system within the cell. All cultures showed improved removal efficiencies in phenolic growth media. These results strongly suggest their use for phenol removal in continuous systems.
- Full Text:
- Date Issued: 1993
- Authors: Goetsch, Patricia-Ann
- Date: 1993
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:21060 , http://hdl.handle.net/10962/6190
- Description: Phenolic compounds are a group of organic chemicals present in the wastewaters of many synthetic industrial processes. Due to their extreme toxicity to man and animals, and deleterious impact on the environment, a range of techniques exist for the effective treatment and disposal of these pollutants. Biological degradation using microbial enzymes presents a valuable alternative to conventional wastewater treatment systems. This research was therefore initiated to investigate the polyphenol oxidase enzyme system and the feasibility of its application for effluent treatment and studies in organic solvents. The enzyme system is widely distributed in nature, with Agaricus bisporus (the common mushroom) being the best known producer. Biochemical investigations of the enzyme system were therefore carried out using this extract. A screening programme was initiated to identify microbial polyphenol oxidase producers which could be cultured in liquid media, thereby enabling the production of large quantities of enzyme in fermentation systems. Extensive growth optimization and enzyme induction and optimization studies were carried out on selected cultures. A number of good producers were isolated, namely a bacterial culture designated AECI culture no. 26, Streptomyces antibioticus, Streptomyces glaucescens and a manipulated strain, Streptomyces lividans (pIJ702). Enzyme production by Agaricus bisporus mycelia was optimized in deep-liquid culture; enzyme extracts showed high phenol removal efficiencies. Streptomyces antibioticus, Streptomyces glaucescens, Streptomyces lividans (pIJ702) and AECI culture no. 26 whole cells were also investigated for phenol-removing ability in simulated phenolic effluents. The use of whole cells reduces enzyme inactivation and instability due to the protection of the enzyme system within the cell. All cultures showed improved removal efficiencies in phenolic growth media. These results strongly suggest their use for phenol removal in continuous systems.
- Full Text:
- Date Issued: 1993
The microbial production of polyphenol oxidase enzyme systems and their application in the treatment of phenolic wastewaters
- Scherman, Patricia Ann (neé Goetch)
- Authors: Scherman, Patricia Ann (neé Goetch)
- Date: 1992
- Subjects: Phenol oxidase Water -- Purification -- Biological treatment Enzymes -- Regulation
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4047 , http://hdl.handle.net/10962/d1004108
- Description: Phenolic compounds are a group of organic chemicals present in the wastewaters of many synthetic industrial processes. Due to their extreme toxicity to man and animals, and deleterious impact on the environment, a range of techniques exist for the effective treatment and disposal of these pollutants. Biological degradation using microbial enzymes presents a valuable alternative to conventional wastewater treatment systems. This research was therefore initiated to investigate the polyphenol oxidase enzyme system and the feasibility of its application for effluent treatment and studies in organic solvents. The enzyme system is widely distributed in nature, with Agaricus bisporus (the common mushroom) being the best known producer. Biochemical investigations of the enzyme system were therefore carried out using this extract. A screening programme was initiated to identify microbial polyphenol oxidase producers which could be cultured in liquid media, thereby enabling the production of large quantities of enzyme in fermentation systems. Extensive growth optimization and enzyme induction and optimization studies were carried out on selected cultures. A number of good producers were isolated, namely a bacterial culture designated AECI culture no. 26, Streptomyces antibioticus, Streptomyces glaucescens and a manipulated strain, Streptomyces lividans (pIJ702). Enzyme production by Agaricus bisporus mycelia was optimized in deep-liquid culture; enzyme extracts showed high phenol removal efficiencies. Streptomyces antibioticus, Streptomyces glaucescens, Streptomyces lividans (pIJ702) and AECI culture no. 26 whole cells were also investigated for phenol-removing ability in simulated phenolic effluents. The use of whole cells reduces enzyme inactivation and instability due to the protection of the enzyme system within the cell. All cultures showed improved removal efficiencies in phenolic growth media. These results strongly suggest their use for phenol removal in continuous systems.
- Full Text:
- Date Issued: 1992
- Authors: Scherman, Patricia Ann (neé Goetch)
- Date: 1992
- Subjects: Phenol oxidase Water -- Purification -- Biological treatment Enzymes -- Regulation
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4047 , http://hdl.handle.net/10962/d1004108
- Description: Phenolic compounds are a group of organic chemicals present in the wastewaters of many synthetic industrial processes. Due to their extreme toxicity to man and animals, and deleterious impact on the environment, a range of techniques exist for the effective treatment and disposal of these pollutants. Biological degradation using microbial enzymes presents a valuable alternative to conventional wastewater treatment systems. This research was therefore initiated to investigate the polyphenol oxidase enzyme system and the feasibility of its application for effluent treatment and studies in organic solvents. The enzyme system is widely distributed in nature, with Agaricus bisporus (the common mushroom) being the best known producer. Biochemical investigations of the enzyme system were therefore carried out using this extract. A screening programme was initiated to identify microbial polyphenol oxidase producers which could be cultured in liquid media, thereby enabling the production of large quantities of enzyme in fermentation systems. Extensive growth optimization and enzyme induction and optimization studies were carried out on selected cultures. A number of good producers were isolated, namely a bacterial culture designated AECI culture no. 26, Streptomyces antibioticus, Streptomyces glaucescens and a manipulated strain, Streptomyces lividans (pIJ702). Enzyme production by Agaricus bisporus mycelia was optimized in deep-liquid culture; enzyme extracts showed high phenol removal efficiencies. Streptomyces antibioticus, Streptomyces glaucescens, Streptomyces lividans (pIJ702) and AECI culture no. 26 whole cells were also investigated for phenol-removing ability in simulated phenolic effluents. The use of whole cells reduces enzyme inactivation and instability due to the protection of the enzyme system within the cell. All cultures showed improved removal efficiencies in phenolic growth media. These results strongly suggest their use for phenol removal in continuous systems.
- Full Text:
- Date Issued: 1992
An investigation into the problems related to the adjustment of beginning-teachers leading to the development of an induction programme
- Authors: Algie, Rowan Craig
- Date: 1983
- Subjects: Teachers, Probationary -- South Africa Teaching -- South Africa
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1411 , http://hdl.handle.net/10962/d1003074
- Description: There is little doubt that there is a widespread concern that the transition from the supportive environment of the training institution where mistakes are expected, self criticism is encouraged and both tutorial guidance and peer group friendship are readily available into a situation where professional and personal responsibilities are profoundly altered, where the methods used, the progress of the pupils, their parents' expectations, the working relationship with colleagues are now permanent responsibilities. This transition can be traumatic for some and a considerable ordeal for many.--Chapter 1, p. 10.
- Full Text:
- Date Issued: 1983
- Authors: Algie, Rowan Craig
- Date: 1983
- Subjects: Teachers, Probationary -- South Africa Teaching -- South Africa
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1411 , http://hdl.handle.net/10962/d1003074
- Description: There is little doubt that there is a widespread concern that the transition from the supportive environment of the training institution where mistakes are expected, self criticism is encouraged and both tutorial guidance and peer group friendship are readily available into a situation where professional and personal responsibilities are profoundly altered, where the methods used, the progress of the pupils, their parents' expectations, the working relationship with colleagues are now permanent responsibilities. This transition can be traumatic for some and a considerable ordeal for many.--Chapter 1, p. 10.
- Full Text:
- Date Issued: 1983
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