An analysis of temporal relations in languages: a comparative study of Mandarin and isiXhosa
- Authors: Ma, Xiujie
- Date: 2013 , 2013-01-30
- Subjects: Chinese language Xhosa language Grammar, Comparative and general -- Temporal constructions
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2367 , http://hdl.handle.net/10962/d1003055
- Description: This study sought to investigate how temporal relations are expressed in Mandarin and isiXhosa. The objective was to compare how two typologically distinct languages, one isolating and the other agglutinating, cope with the encoding of situations that occur at different positions on the time line. Data was drawn from questionnaire responses from, and interviews with, isiXhosa speakers who provided translations of a wide range of sentences from English into isiXhosa. The study revealed that isiXhosa relies on the grammatical category – tense – to encode temporal relations, while Mandarin relies more on lexical and pragmatic devices – the use of temporal adverbials and the implication of aspectual markings – to locate a situation on the time line. Typically, each sentence in isiXhosa must be marked for tense: temporal adverbials are optional elements and used to more precisely locate the situation on the time line. By contrast, in Mandarin, temporal adverbials have a more central function in that they independently express different positions on the time line: without temporal adverbials, it is extremely difficult to locate a situation on the time line in some sentences. Another important difference between the two languages was revealed in this study: isiXhosa grammar allows speakers to talk about situations in terms of their distance (past or future) from the speech time whereas Mandarin grammar allows its speakers to talk about situations in terms of the internal properties (e.g. completed, ongoing, etc.) of those situations. The study revealed that isiXhosa and Mandarin are similar in one important respect: both languages have no formal properties, i.e. overt tense markers (isiXhosa) and compulsory temporal adverbials or other temporal devices (Mandarin) for marking the temporal location of present situations. The study also revealed that both languages encode ‘pastness’ in terms of whether or not the effects of the situation in question still remain at speech time.
- Full Text:
- Date Issued: 2013
- Authors: Ma, Xiujie
- Date: 2013 , 2013-01-30
- Subjects: Chinese language Xhosa language Grammar, Comparative and general -- Temporal constructions
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2367 , http://hdl.handle.net/10962/d1003055
- Description: This study sought to investigate how temporal relations are expressed in Mandarin and isiXhosa. The objective was to compare how two typologically distinct languages, one isolating and the other agglutinating, cope with the encoding of situations that occur at different positions on the time line. Data was drawn from questionnaire responses from, and interviews with, isiXhosa speakers who provided translations of a wide range of sentences from English into isiXhosa. The study revealed that isiXhosa relies on the grammatical category – tense – to encode temporal relations, while Mandarin relies more on lexical and pragmatic devices – the use of temporal adverbials and the implication of aspectual markings – to locate a situation on the time line. Typically, each sentence in isiXhosa must be marked for tense: temporal adverbials are optional elements and used to more precisely locate the situation on the time line. By contrast, in Mandarin, temporal adverbials have a more central function in that they independently express different positions on the time line: without temporal adverbials, it is extremely difficult to locate a situation on the time line in some sentences. Another important difference between the two languages was revealed in this study: isiXhosa grammar allows speakers to talk about situations in terms of their distance (past or future) from the speech time whereas Mandarin grammar allows its speakers to talk about situations in terms of the internal properties (e.g. completed, ongoing, etc.) of those situations. The study revealed that isiXhosa and Mandarin are similar in one important respect: both languages have no formal properties, i.e. overt tense markers (isiXhosa) and compulsory temporal adverbials or other temporal devices (Mandarin) for marking the temporal location of present situations. The study also revealed that both languages encode ‘pastness’ in terms of whether or not the effects of the situation in question still remain at speech time.
- Full Text:
- Date Issued: 2013
Exploring the influence of spirituality on students' well-being
- Authors: Magula, Nokuzola Princess
- Date: 2013
- Subjects: Sprituality , Well-being , Students , Christians , Rhodes University , College students -- Religious life -- South Africa -- Eastern Cape , Christian college students -- Religious life -- South Africa -- Eastern Cape , Universities and colleges -- Religion -- Research , Well-being -- Religious aspects , Spirituality -- Research
- Language: English
- Type: text , Thesis , Masters , MA
- Identifier: vital:2918 , http://hdl.handle.net/10962/d1002083
- Description: This study was aimed at exploring the impact of spirituality on the well-being of students at Rhodes University in South Africa. The study was conducted within a qualitative research paradigm deploying an interpretive phenomenological analysis strategy for data analysis. The study involved a sample of four female Honours students who were all active Christians. The selected students were interviewed to elicit their experiences of spirituality and how this related to their everyday lives. The study used semi-structured interviews in order to get as much information as possible from the small sample of research participants. Data generated in this study was processed, presented and interpreted inductively and hermeneutically in order to identify emerging superordinate themes. This study found that spirituality was experienced as having a positive impact on well-being by all the four students. The study revealed that belief and faith in God amongst the students resulted in enhanced and positive experiences of hope, optimism and compassion which provided the students with a deeper sense of meaning of life and a source of direction in difficult times. The study further showed that participants experienced spirituality as a regulatory mechanism shaping their lifestyles and behaviours. Participants viewed their spirituality and religiosity as a source of social support helping them to cope with distressful situations. The findings of this study are consistent with the findings of previous studies done in the field of psychology and spirituality. The fact that this study has shown that spirituality and religion has a positive impact on student’s well-being may mean that University administrators and psychologists may find the study interesting and valuable
- Full Text:
- Date Issued: 2013
- Authors: Magula, Nokuzola Princess
- Date: 2013
- Subjects: Sprituality , Well-being , Students , Christians , Rhodes University , College students -- Religious life -- South Africa -- Eastern Cape , Christian college students -- Religious life -- South Africa -- Eastern Cape , Universities and colleges -- Religion -- Research , Well-being -- Religious aspects , Spirituality -- Research
- Language: English
- Type: text , Thesis , Masters , MA
- Identifier: vital:2918 , http://hdl.handle.net/10962/d1002083
- Description: This study was aimed at exploring the impact of spirituality on the well-being of students at Rhodes University in South Africa. The study was conducted within a qualitative research paradigm deploying an interpretive phenomenological analysis strategy for data analysis. The study involved a sample of four female Honours students who were all active Christians. The selected students were interviewed to elicit their experiences of spirituality and how this related to their everyday lives. The study used semi-structured interviews in order to get as much information as possible from the small sample of research participants. Data generated in this study was processed, presented and interpreted inductively and hermeneutically in order to identify emerging superordinate themes. This study found that spirituality was experienced as having a positive impact on well-being by all the four students. The study revealed that belief and faith in God amongst the students resulted in enhanced and positive experiences of hope, optimism and compassion which provided the students with a deeper sense of meaning of life and a source of direction in difficult times. The study further showed that participants experienced spirituality as a regulatory mechanism shaping their lifestyles and behaviours. Participants viewed their spirituality and religiosity as a source of social support helping them to cope with distressful situations. The findings of this study are consistent with the findings of previous studies done in the field of psychology and spirituality. The fact that this study has shown that spirituality and religion has a positive impact on student’s well-being may mean that University administrators and psychologists may find the study interesting and valuable
- Full Text:
- Date Issued: 2013
Immobilisation of electric eel acetylcholinesterase on nanofibres electrospun from a nylon and chitosan blend
- Authors: Mafuma, Tendai Simbarashe
- Date: 2013
- Subjects: Acetylcholinesterase Acetylcholinesterase -- Inhibitors Electric eel Biosensors Immobilized enzymes Pesticides -- Environmental aspects Pesticides -- Toxicology Nylon Chitosan Nanofibers Electrospinning
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3886 , http://hdl.handle.net/10962/d1001620
- Description: Organophosphates and carbamates are potent inhibitors of the neurotransmitter acetylcholinesterase. This inhibition results in the blocking of nerve signal transference into the post synaptic neuron leading to loss of muscle action and death. Because of the universal mechanisms of signal transduction in animals, these inhibitors have been widely used as agricultural pesticides as well as chemical warfare agents (nerve agents). Health issues associated with pesticide usage result from the fact that both the pesticides and their breakdown products often end up in water and food sources as well as in the soil. As a result, there has been an increase in the number of studies aimed at the detection of these pesticides in the environment. One popular research area is enzyme based biosensor construction. Some important criteria for consideration during the construction of biosensors are the importance of a suitable solid support as well as the enzyme immobilisation method. Recently, there has been increased interest in using nano-scale material e.g. using nanoparticles as enzyme support material. This is largely due to their advantages such as large surface area to volume ratio as well as reduced mass transfer resistance. Electrospinning is a straight forward and cost effective method for producing nanofibres from any soluble polymer(s). The applications of electrospun nanofibres have been reported in clinical studies, biofuel production as well as bioremediation. In this study two polymers were selected: nylon for its mechanical stability and chitosan for its biocompatibility and hydrophilicity, for the fabrication of electrospun nanofibres which would function as immobilisation support material for acetylcholinesterase. The first objective of this study was to electrospin nanofibres from a nylon-6 and chitosan blend solution. A binary solvent system consisting of formic acid and acetic acid (50:50) successfully dissolved and blended the polymers which were subsequently electrospun. Scanning electron microscopy characterisation of the nanofibres showed that (i) a nylon-6: chitosan ratio of 16%: 3% resulted in the formation of bead free nanofibres and (ii) the fibres were collected in non-woven mats characterised by different size nanofibres with average diameters of 250 nm for the main fibres and 40 nm for the smaller nanofibres. Fourier transform infra-red (FT-IR) analysis of the nanofibres indicated that a new product had been formed during the blending of the two polymers. The second aim of the study was to carry out a facile immobilisation of electric eel acetylcholinesterase via glutaraldehyde (GA) cross-linking. Glutaraldehyde solution 5% (v/v) resulted in the immobilisation of 0.334 mg/cm² of acetylcholinesterase onto the nanofibres. The immobilisation procedure was optimised with reference to acetylcholinestease and crosslinker concentrations, incubation time and the cross-linking method. A comparative investigation into the optimum pH and temperature conditions, pH and thermal stabilities, substrate and inhibition kinetics was then carried out on free and immobilised acetylcholinesterase. The final objective of this study was to determine the storage stabilities of the immobilised and free enzymes as well as the reusability characteristics of the immobilised acetylcholinesterase. Several conclusions were drawn from this study. Acetylcholinesterase was successfully immobilised onto the surface of nylon-6:chitosan nanofibres with retention of its activity. There was a shift in the pH optimum of the immobilised acetylcholineseterase by 0.5 units towards a neutral pH. Although both free and immobilised acetylcholinesterase exhibited the same optimum temperature, immobilised acetylcholinesterase showed enhanced thermal stability. In terms of pH stability, immobilised acetylcholinesterase showed greater stability at acidic pH whilst free acetylcholinesterase was more stable under alkaline pH conditions. Relative to free acetylcholinesterase, the immobilised enzyme showed considerable storage stability retaining ~50% of its activity when stored for 49 days at 4°C. Immobilised acetylcholinesterase also retained > 20% of its initial activity after 9 consecutive reuse cycles. When exposed to fixed concentrations of carbofuran or demeton-S-methyl sulfone, immobilised acetylcholinesterase showed similar inhibition characteristics to that of the free enzyme. The decrease in enzyme activity observed after immobilisation to the nanofibres may have been due to several reasons which include some enzyme molecules being immobilised in structural conformations which reduced substrate access to the catalytic site, participation of the catalytic residues in immobilisation and enzyme denaturation due to the reaction conditions used for acetylcholinesterase immobilisation. Similar observations have been widely reported in literature and this is one of the major drawbacks of enzyme immobilisation. In conclusion, nylon-6:chitosan electrospun nanofibres were shown to be suitable supports for facile acetylcholinesterase immobilisation and the immobilised enzyme has potential for use in pesticide detection. Future recommendations for this study include a comparative study of the GA cross-linking method for AChE immobilisation which will lead to more intensely bound enzyme molecules to prevent non-specific binding. An investigation into the effect of inhibitors on stored immobilised AChE, as well as reactivation and reuse studies, may also be useful for determining the cost-effectiveness of reusing immobilised AChE for pesticide detection in environmental water samples. Several models have been designed for the determination of the kinetic parameters for immobilised enzymes. These take into account the mass transfer resistance as well as the overall charge of the immobilisation matrix. The use of these models to analyse experimental data will give a clear understanding of the effects of immobilisation on enzyme activity
- Full Text:
- Date Issued: 2013
- Authors: Mafuma, Tendai Simbarashe
- Date: 2013
- Subjects: Acetylcholinesterase Acetylcholinesterase -- Inhibitors Electric eel Biosensors Immobilized enzymes Pesticides -- Environmental aspects Pesticides -- Toxicology Nylon Chitosan Nanofibers Electrospinning
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3886 , http://hdl.handle.net/10962/d1001620
- Description: Organophosphates and carbamates are potent inhibitors of the neurotransmitter acetylcholinesterase. This inhibition results in the blocking of nerve signal transference into the post synaptic neuron leading to loss of muscle action and death. Because of the universal mechanisms of signal transduction in animals, these inhibitors have been widely used as agricultural pesticides as well as chemical warfare agents (nerve agents). Health issues associated with pesticide usage result from the fact that both the pesticides and their breakdown products often end up in water and food sources as well as in the soil. As a result, there has been an increase in the number of studies aimed at the detection of these pesticides in the environment. One popular research area is enzyme based biosensor construction. Some important criteria for consideration during the construction of biosensors are the importance of a suitable solid support as well as the enzyme immobilisation method. Recently, there has been increased interest in using nano-scale material e.g. using nanoparticles as enzyme support material. This is largely due to their advantages such as large surface area to volume ratio as well as reduced mass transfer resistance. Electrospinning is a straight forward and cost effective method for producing nanofibres from any soluble polymer(s). The applications of electrospun nanofibres have been reported in clinical studies, biofuel production as well as bioremediation. In this study two polymers were selected: nylon for its mechanical stability and chitosan for its biocompatibility and hydrophilicity, for the fabrication of electrospun nanofibres which would function as immobilisation support material for acetylcholinesterase. The first objective of this study was to electrospin nanofibres from a nylon-6 and chitosan blend solution. A binary solvent system consisting of formic acid and acetic acid (50:50) successfully dissolved and blended the polymers which were subsequently electrospun. Scanning electron microscopy characterisation of the nanofibres showed that (i) a nylon-6: chitosan ratio of 16%: 3% resulted in the formation of bead free nanofibres and (ii) the fibres were collected in non-woven mats characterised by different size nanofibres with average diameters of 250 nm for the main fibres and 40 nm for the smaller nanofibres. Fourier transform infra-red (FT-IR) analysis of the nanofibres indicated that a new product had been formed during the blending of the two polymers. The second aim of the study was to carry out a facile immobilisation of electric eel acetylcholinesterase via glutaraldehyde (GA) cross-linking. Glutaraldehyde solution 5% (v/v) resulted in the immobilisation of 0.334 mg/cm² of acetylcholinesterase onto the nanofibres. The immobilisation procedure was optimised with reference to acetylcholinestease and crosslinker concentrations, incubation time and the cross-linking method. A comparative investigation into the optimum pH and temperature conditions, pH and thermal stabilities, substrate and inhibition kinetics was then carried out on free and immobilised acetylcholinesterase. The final objective of this study was to determine the storage stabilities of the immobilised and free enzymes as well as the reusability characteristics of the immobilised acetylcholinesterase. Several conclusions were drawn from this study. Acetylcholinesterase was successfully immobilised onto the surface of nylon-6:chitosan nanofibres with retention of its activity. There was a shift in the pH optimum of the immobilised acetylcholineseterase by 0.5 units towards a neutral pH. Although both free and immobilised acetylcholinesterase exhibited the same optimum temperature, immobilised acetylcholinesterase showed enhanced thermal stability. In terms of pH stability, immobilised acetylcholinesterase showed greater stability at acidic pH whilst free acetylcholinesterase was more stable under alkaline pH conditions. Relative to free acetylcholinesterase, the immobilised enzyme showed considerable storage stability retaining ~50% of its activity when stored for 49 days at 4°C. Immobilised acetylcholinesterase also retained > 20% of its initial activity after 9 consecutive reuse cycles. When exposed to fixed concentrations of carbofuran or demeton-S-methyl sulfone, immobilised acetylcholinesterase showed similar inhibition characteristics to that of the free enzyme. The decrease in enzyme activity observed after immobilisation to the nanofibres may have been due to several reasons which include some enzyme molecules being immobilised in structural conformations which reduced substrate access to the catalytic site, participation of the catalytic residues in immobilisation and enzyme denaturation due to the reaction conditions used for acetylcholinesterase immobilisation. Similar observations have been widely reported in literature and this is one of the major drawbacks of enzyme immobilisation. In conclusion, nylon-6:chitosan electrospun nanofibres were shown to be suitable supports for facile acetylcholinesterase immobilisation and the immobilised enzyme has potential for use in pesticide detection. Future recommendations for this study include a comparative study of the GA cross-linking method for AChE immobilisation which will lead to more intensely bound enzyme molecules to prevent non-specific binding. An investigation into the effect of inhibitors on stored immobilised AChE, as well as reactivation and reuse studies, may also be useful for determining the cost-effectiveness of reusing immobilised AChE for pesticide detection in environmental water samples. Several models have been designed for the determination of the kinetic parameters for immobilised enzymes. These take into account the mass transfer resistance as well as the overall charge of the immobilisation matrix. The use of these models to analyse experimental data will give a clear understanding of the effects of immobilisation on enzyme activity
- Full Text:
- Date Issued: 2013
Professional behaviour among nursing students at a college in the Eastern Cape
- Authors: Magopeni, Sibongile Nomvuyo
- Date: 2013
- Language: English
- Type: Thesis , Masters , MSc (Nursing Science)
- Identifier: vital:11929 , http://hdl.handle.net/10353/d1021322
- Description: The focus of the study was to explore and describe reasons for poor professional behaviour among nursing students at a public nursing college in the Eastern Cape. The objectives of the study were to explore and describe the reasons for poor professional behaviour among nursing students and to describe strategies to improve poor professional behaviour. The study has significance for the college management, staff, nursing students, registered nurses and everyone involved in professional development of nursing students. The population for this study consisted of third-year nursing students following the four-year comprehensive basic course for registration leading to the Diploma in Nursing (General, Community & Psychiatry) and Midwifery at a public nursing college. The research questions were: What do you understand by professional behaviour? What are the reasons for poor professional behaviour among nursing students? What could be done to improve professionalism among college nursing students? A qualitative, explorative, descriptive and contextual design was used as a framework for the study. Permission to conduct the study was obtained from the University of Fort Hare ethics committee and other relevant authorities as indicated in the study. Ethical principles were maintained and informed consent obtained. Data collection was done using focus groups and an audiotape with a purposefully sampling of 30 third-year nursing students at the public college of nursing. Data were analysed using Tesch’s method of analysis for qualitative research. Three major themes emerged: students’ understanding of professional behaviour, reasons for poor professional behaviour and methods to improve poor professional behaviour. It was concluded that poor professional behaviour has an effect on professionalism and it should be addressed and corrected for protecting the professional image. Recommendations: Policies regarding inappropriate professional behaviour at the college should be in place and easily accessible to every staff member and nursing student. Department of Health should conduct reflective courses and seminars on professionalism and these should begin at the same time as the academic programme.
- Full Text:
- Date Issued: 2013
- Authors: Magopeni, Sibongile Nomvuyo
- Date: 2013
- Language: English
- Type: Thesis , Masters , MSc (Nursing Science)
- Identifier: vital:11929 , http://hdl.handle.net/10353/d1021322
- Description: The focus of the study was to explore and describe reasons for poor professional behaviour among nursing students at a public nursing college in the Eastern Cape. The objectives of the study were to explore and describe the reasons for poor professional behaviour among nursing students and to describe strategies to improve poor professional behaviour. The study has significance for the college management, staff, nursing students, registered nurses and everyone involved in professional development of nursing students. The population for this study consisted of third-year nursing students following the four-year comprehensive basic course for registration leading to the Diploma in Nursing (General, Community & Psychiatry) and Midwifery at a public nursing college. The research questions were: What do you understand by professional behaviour? What are the reasons for poor professional behaviour among nursing students? What could be done to improve professionalism among college nursing students? A qualitative, explorative, descriptive and contextual design was used as a framework for the study. Permission to conduct the study was obtained from the University of Fort Hare ethics committee and other relevant authorities as indicated in the study. Ethical principles were maintained and informed consent obtained. Data collection was done using focus groups and an audiotape with a purposefully sampling of 30 third-year nursing students at the public college of nursing. Data were analysed using Tesch’s method of analysis for qualitative research. Three major themes emerged: students’ understanding of professional behaviour, reasons for poor professional behaviour and methods to improve poor professional behaviour. It was concluded that poor professional behaviour has an effect on professionalism and it should be addressed and corrected for protecting the professional image. Recommendations: Policies regarding inappropriate professional behaviour at the college should be in place and easily accessible to every staff member and nursing student. Department of Health should conduct reflective courses and seminars on professionalism and these should begin at the same time as the academic programme.
- Full Text:
- Date Issued: 2013
Profiling for volatile compounds in the Kgalagadi desert truffle
- Authors: Bogopa, Juda
- Date: 2013
- Subjects: Desert plants -- Botswana -- Kgalagadi District Supercritical fluid extraction Gas chromatography Mass spectrometry Tuberaceae -- Analysis -- Botswana -- Kgalagadi District Truffles -- Analysis -- Botswana -- Kgalagadi District
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4280 , http://hdl.handle.net/10962/d1002006
- Description: The thesis focuses on ‘green’ sample preparation techniques that utilise minimal or no organic solvents thereby producing negligible volumes of organic waste, to ensure safety both to user and the environment. Volatile compounds were extracted and pre-concentrated from Kgalagadi desert truffles (kalaharituber) by headspace solid phase microextraction (HSSPME) and supercritical fluid extraction (SFE). PHWE was employed for the extraction of amino acids and fatty acids. Subsequent analysis of volatile compounds was carried out by gas chromatography coupled with mass spectrometry. Four types of HS-SPME fibers (PDMS 100 μm, PDMS 7 μm, Polyacrylate 85 μm, CAR/DVB/PDMS 50/30 μm) were evaluated. A total of 24 volatile compounds with a molecular weight range from 110 to 354, the most prominent peak being 2-t-Butyl-2,3-dimethyl-3-buten-1-ol (C₁₀H₂₀O, MW 156) were detected after sampling with a PDMS 100 μm fiber. Less volatile compounds were detected after SFE with CO2. A total of 16 amino acids were identified while 17 fatty acids (MW from 132.12 to 367.49) were also identified. The characteristic profile of the Kgalagadi desert truffle was found to contain mainly fatty acid methyl esters and unsaturated aliphatic hydrocarbons. The most prominent compound peaks identified were; 2-t-butyl-2,3-dimethyl- 3-buten-1-ol, disulfide, ethyl benzoic acid 2-4-dhydroxy-3,6-dimethyl-methyl ester, 8,11- octadecanoic acid methyl ester, benzoic acid, 2,4-dihydroxy-3,6-dimethyl-methyl ester, isoquinoline, 1 butyl-3,4-dihydro and 3-heptanone, 6 methyl. Optimization results indicated that fresh slices from the heart of truffles were the best to use for HS-SPME-GCMS volatile compound analysis as they showed a higher sensitivity
- Full Text:
- Date Issued: 2013
- Authors: Bogopa, Juda
- Date: 2013
- Subjects: Desert plants -- Botswana -- Kgalagadi District Supercritical fluid extraction Gas chromatography Mass spectrometry Tuberaceae -- Analysis -- Botswana -- Kgalagadi District Truffles -- Analysis -- Botswana -- Kgalagadi District
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4280 , http://hdl.handle.net/10962/d1002006
- Description: The thesis focuses on ‘green’ sample preparation techniques that utilise minimal or no organic solvents thereby producing negligible volumes of organic waste, to ensure safety both to user and the environment. Volatile compounds were extracted and pre-concentrated from Kgalagadi desert truffles (kalaharituber) by headspace solid phase microextraction (HSSPME) and supercritical fluid extraction (SFE). PHWE was employed for the extraction of amino acids and fatty acids. Subsequent analysis of volatile compounds was carried out by gas chromatography coupled with mass spectrometry. Four types of HS-SPME fibers (PDMS 100 μm, PDMS 7 μm, Polyacrylate 85 μm, CAR/DVB/PDMS 50/30 μm) were evaluated. A total of 24 volatile compounds with a molecular weight range from 110 to 354, the most prominent peak being 2-t-Butyl-2,3-dimethyl-3-buten-1-ol (C₁₀H₂₀O, MW 156) were detected after sampling with a PDMS 100 μm fiber. Less volatile compounds were detected after SFE with CO2. A total of 16 amino acids were identified while 17 fatty acids (MW from 132.12 to 367.49) were also identified. The characteristic profile of the Kgalagadi desert truffle was found to contain mainly fatty acid methyl esters and unsaturated aliphatic hydrocarbons. The most prominent compound peaks identified were; 2-t-butyl-2,3-dimethyl- 3-buten-1-ol, disulfide, ethyl benzoic acid 2-4-dhydroxy-3,6-dimethyl-methyl ester, 8,11- octadecanoic acid methyl ester, benzoic acid, 2,4-dihydroxy-3,6-dimethyl-methyl ester, isoquinoline, 1 butyl-3,4-dihydro and 3-heptanone, 6 methyl. Optimization results indicated that fresh slices from the heart of truffles were the best to use for HS-SPME-GCMS volatile compound analysis as they showed a higher sensitivity
- Full Text:
- Date Issued: 2013
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