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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Effects of environmental growth conditions on the levels of sutherlandins 3 and 4 and sutherlandiosides B and D, in Sutherlandia frutescens (L.) R. Br.

Whisgary, Darryn January 2011 (has links)
>Magister Scientiae - MSc / Sutherlandia frutescens (L.) R. Br. (Fabaceae), indigenous to the Western Cape region of South Africa, is found in a Mediterranean-type climate known for its many environmental stressors that can influence the levels of metabolites found in plants. Sutherlandia frutescens contains many known potential active constituents among them, flavonoids such as sutherlandins 3 and 4 (Su3 and Su4) and terpenoids such as sutherlandiosides B and D (SuB and SuD). Whether the profiles and levels of Su3, Su4, SuB and SuD are significantly affected by the environmental factors found in this area is however, unknown. iBatech™ is an ethanolic plant extract that is manufactured by researchers in the Department of Medical Biosciences, UWC, for use as a pesticide. HPLC analysis performed on Lycopersicon species treated with the iBatech™ product have shown that it also caused an increase in the concentrations of total polyphenols in the plant (Klaasen et.al., unpublished data). Whether the treatment with iBatech™ might also cause an increase in the polyphenols such as sutherlandins 3 and 4 and sutherlandiosides B and D is also unknown. The objectives of this study were to determine the concentrations of sutherlandins 3 and 4 (Su3 and Su4) and sutherlandiosides B and D (SuB and SuD) in S. frutescens collected from different sites and after the treatment with the iBatech™ product. The specific objectives were: a) to locate and categorize sites where S. frutescens is grown, based on a selection of pertinent environmental growth factors, b) to determine and compare the concentrations of sutherlandins 3 and 4 and sutherlandiosides B and D in S. frutescens collected from the different environmental growth sites and after treatment with the iBatech™ product. To realize these objectives, S. frutescens samples were collected from eight different sites and broadly categorized into three environmental categories. A high-performance liquid chromatography (HPLC) method using diode array ultraviolet detection (HPLC-DAD) for the simultaneous analysis of flavonoids and terpenoids was developed and validated, and used for the profiling and determination of the average levels of sutherlandins 3 and 4 and sutherlandiosides B and D in the samples from the sites and that treated with the iBatech™ product. The Kruskal-Wallis test was used to determine statistically significant differences among the environmental categories. The post ANOVA, Dunn's Multiple Comparison test was performed to determine which groups were significantly different. The Mann-Whitney, two-tail, t-test was used to compare each environmental category to the standard and the column statistics of the raw data was analyzed to determine significant differences among samples from the same environmental category. In the samples collected from the sites, the values represent the average levels of metabolites for each environmental category whereas the significance values indicated were among samples from the same environmental category. The levels for sutherlandin 3 were Afriplex™ (Std.) 2495.08, the natural field (NF) 2810.33 (P=0.0005), the cultivated field (CF) 2519.81 and the greenhouse (GH) 2580.25. The levels for sutherlandin 4 were significantly different when comparing the (NF) 1495.67 (P=0.0001), (CF) 3114.42 (P=0.0140) and (GH) 2361.72 (P=0.0001), with the CF group showing the highest levels of Su4 and the NF showing the lowest. The levels for sutherlandioside B were (NF) 189.7 (P=0.0189), (CF) 594.56 (P=0.0140) and (GH) 326.72 (P=0.0001), however, the CF group showed the highest average levels for SuB. The levels for sutherlandioside D were (NF) 144.1 (P=0.0192), (CF) 544.37 (P=0.0308) and (GH) 387.49 (P=0.0001), with the NF category having the lowest average levels. In the iBatech™ treated samples, the values indicate the average levels of three samples in each treatment group. The levels for sutherlandin 3 were (control) 9758.43, the (50%) 2232.63 and the (100%) 2031.97 treatment groups. The levels for sutherlandin 4) were (control) 2241.63, the (50%) 2247.47 and the (100%) 2392.60, with the 100% treatment group having the highest levels. The levels for sutherlandioside B were (control) 289.66, the (50%) 284.93 and the (100%) 332.30. The levels for sutherlandioside D were (control) 282.77, the (50%) 280.60 and the (100%) 315.13 treatment groups, with the 100% treatment group having the highest levels. The levels of Su3, Su4, SuB and SuD were significantly different (P=0.0001) among all treatment groups. In conclusion, the data shows that only sutherlandin 4 (Su4) was significantly different when comparing the environmental groups. Due to the significant differences in the Su3, Su4, SuB and SuD levels among samples from the same group the levels of these metabolites cannot be correlated with the environmental groups.
2

The impact of storage time and seasonal harvesting on biomarker levels of Lessertia frutescens

Campbell, James January 2012 (has links)
<p>In South Africa, it is estimated that approximately 70% of the population frequently make use of traditional medicinal plants for their health care needs. The use of Lessertia frutescens by the&nbsp / various cultural groups in South Africa dates back to the earlier civilizations and continues to be used today to treat a multitude of ailments. To get the best results from a medicinal plant, one&nbsp / &nbsp / would need to ensure that the crude material is of good quality through interventions like being properly grown, well dried and correctly processed. This would add a measure of quality&nbsp / assurance, which will contribute towards the safety and efficacy aspect of herbal medicine. The aim of this study was to investigate what impact a particular season of harvest and the time in&nbsp / storage would have on the flavonoid and triterpenoid marker levels of Lessertia frutescens. To achieve this, the following was investigated: (1) storage variation of Lessertia frutescens leaves&nbsp / by comparing the results obtained from the High Performance Liquid Chromatography (HPLC) analysis of the flavonoids and triterpenoids, (2) seasonal variation of Lessertia frutescens&nbsp / leaves by comparing the results obtained from the HPLC analysis of the flavonoids and triterpenoids, (3) leaf and stem variation of Lessertia frutescens by comparing the results obtained from HPLC analysis of the flavonoids and triterpenoids. The hypotheses were: (1) the stored sample would indicate the same level of the biomarkers for the flavonoids and triterpenoids, as that of&nbsp / the freshly prepared sample, (2) the sample that was harvested during the summer season would indicate higher levels of the biomarkers of&nbsp / flavonoids and triterpenoids than the other three&nbsp / seasons, (3) the leaf sample would indicate the same level of the biomarkers for the flavonoids and triterpenoids, as that of the stem sample. An Agilent 1200 series HPLC was used for the&nbsp / determination of the flavonoids sutherlandin A and sutherlandin D as well as the triterpenoids sutherlandioside B and sutherlandioside D. Results show that for both sutherlandin A (summer:&nbsp / 3.67 &plusmn / 2.88 mg/ml / storage: 4.07 &plusmn / 2.88 mg/ml) and D (summer: 4.10 &plusmn / 1.06 mg/ml / storage: 4.25 &plusmn / 1.06 mg/ml) show significantly (P &lt / 0.0001) higher concentrations in the case of the storage&nbsp / amples. For both sutherlandioside B (summer: 3.01 &plusmn / 0.39 mg/ml / storage: 2.82 &plusmn / 0.39 mg/ml) and D (summer: 5.82 &plusmn / 0.42 mg/ml / storage: 4.66 &plusmn / 0.42 mg/ml) show significantly (P &lt / &nbsp / .0001)&nbsp / higher concentrations in the case of the fresh summer samples.For the seasonal comparison, results show that for sutherlandin A (summer: 3.67 &plusmn / 12.49 mg/ml / autumn: 4.75 &plusmn / &nbsp / 12.49 mg/ml / winter: 4.23 &plusmn / 12.49 mg/ml / spring: 6.56 &plusmn / 12.49 mg/ml) show significantly (P &lt / 0.0001) higher concentrations in the case of the spring sample. For sutherlandin D (summer: 4.10&nbsp / &nbsp / 10.32 mg/ml / autumn: 6.37 &plusmn / 10.32 mg/ml / winter: 5.25 &plusmn / 10.32 mg/ml / spring / 6.08 &plusmn / 10.32 mg/ml) show significantly (P &lt / 0.0001) higher concentrations in the case of the autumn sample. For both sutherlandioside B (summer: 3.01 &plusmn / 7.19 mg/ml / autumn: 2.15 &plusmn / 7.19 mg/ml / winter: 2.89 &plusmn / 7.19 mg/ml / spring: 1.47 &plusmn / 7.19 mg/ml) and D (summer: 5.82 &plusmn / 14.48 mg/ml / autumn: 3.33 &plusmn / 14.48 mg/ml / winter: 4.23 &plusmn / 14.48 mg/ml / spring: 2.50 &plusmn / 14.48 mg/ml) show significantly (P &lt / 0.0001) higher concentrations in the case of the autumn sample. For the summer&nbsp / leaf/stem comparison, results show that for sutherlandin A (leaf: 3.67 &plusmn / 8.18 mg/ml / stem: 4.67 &plusmn / 8.18 mg/ml) show significantly (P &lt / 0.0001) higher concentrations in the case of the stem&nbsp / sample. For the sutherlandin D (leaf: 4.10 &plusmn / 4.81 mg/ml / stem: 3.31 &plusmn / 4.81 mg/ml) show significantly (P &lt / 0.0001) higher concentrations in the case of the summer leaf sample. For both the&nbsp / sutherlandioside B (leaf: 3.01 &plusmn / 4.24 mg/ml / stem: 3.62 &plusmn / 4.24 mg/ml) and D (leaf: 5.82 &plusmn / 0.42 mg/ml / stem: 5.80 &plusmn / 0.42 mg/ml) show significantly (P &lt / 0.0001) higher concentrations in the&nbsp / case of the stem samples. Results demonstrate that the production of secondary metabolites are influenced by&nbsp / &nbsp / environmental factors like seasonal harvesting, as indicated by the variation in the chemical constituent composition of Lessertia frutescens depending on the season collected in. Moreover, the storage of Lessertia frutescens for a period of one year resulted in an&nbsp / increase of two of the four constituents being monitored. There was slight variations in the chemical constituents, depending on whether the leaf or stem material of Lessertia frutescens was being used. Finally, the type of chemical constituent being monitored was also important in the consideration of this study. Therefore, this study can be seen as a starting point to further&nbsp / &nbsp / investigations of these aspects, which are of clinical, pharmacological and economic</p>
3

The impact of storage time and seasonal harvesting on biomarker levels of Lessertia frutescens

Campbell, James January 2012 (has links)
<p>In South Africa, it is estimated that approximately 70% of the population frequently make use of traditional medicinal plants for their health care needs. The use of Lessertia frutescens by the&nbsp / various cultural groups in South Africa dates back to the earlier civilizations and continues to be used today to treat a multitude of ailments. To get the best results from a medicinal plant, one&nbsp / &nbsp / would need to ensure that the crude material is of good quality through interventions like being properly grown, well dried and correctly processed. This would add a measure of quality&nbsp / assurance, which will contribute towards the safety and efficacy aspect of herbal medicine. The aim of this study was to investigate what impact a particular season of harvest and the time in&nbsp / storage would have on the flavonoid and triterpenoid marker levels of Lessertia frutescens. To achieve this, the following was investigated: (1) storage variation of Lessertia frutescens leaves&nbsp / by comparing the results obtained from the High Performance Liquid Chromatography (HPLC) analysis of the flavonoids and triterpenoids, (2) seasonal variation of Lessertia frutescens&nbsp / leaves by comparing the results obtained from the HPLC analysis of the flavonoids and triterpenoids, (3) leaf and stem variation of Lessertia frutescens by comparing the results obtained from HPLC analysis of the flavonoids and triterpenoids. The hypotheses were: (1) the stored sample would indicate the same level of the biomarkers for the flavonoids and triterpenoids, as that of&nbsp / the freshly prepared sample, (2) the sample that was harvested during the summer season would indicate higher levels of the biomarkers of&nbsp / flavonoids and triterpenoids than the other three&nbsp / seasons, (3) the leaf sample would indicate the same level of the biomarkers for the flavonoids and triterpenoids, as that of the stem sample. An Agilent 1200 series HPLC was used for the&nbsp / determination of the flavonoids sutherlandin A and sutherlandin D as well as the triterpenoids sutherlandioside B and sutherlandioside D. Results show that for both sutherlandin A (summer:&nbsp / 3.67 &plusmn / 2.88 mg/ml / storage: 4.07 &plusmn / 2.88 mg/ml) and D (summer: 4.10 &plusmn / 1.06 mg/ml / storage: 4.25 &plusmn / 1.06 mg/ml) show significantly (P &lt / 0.0001) higher concentrations in the case of the storage&nbsp / amples. For both sutherlandioside B (summer: 3.01 &plusmn / 0.39 mg/ml / storage: 2.82 &plusmn / 0.39 mg/ml) and D (summer: 5.82 &plusmn / 0.42 mg/ml / storage: 4.66 &plusmn / 0.42 mg/ml) show significantly (P &lt / &nbsp / .0001)&nbsp / higher concentrations in the case of the fresh summer samples.For the seasonal comparison, results show that for sutherlandin A (summer: 3.67 &plusmn / 12.49 mg/ml / autumn: 4.75 &plusmn / &nbsp / 12.49 mg/ml / winter: 4.23 &plusmn / 12.49 mg/ml / spring: 6.56 &plusmn / 12.49 mg/ml) show significantly (P &lt / 0.0001) higher concentrations in the case of the spring sample. For sutherlandin D (summer: 4.10&nbsp / &nbsp / 10.32 mg/ml / autumn: 6.37 &plusmn / 10.32 mg/ml / winter: 5.25 &plusmn / 10.32 mg/ml / spring / 6.08 &plusmn / 10.32 mg/ml) show significantly (P &lt / 0.0001) higher concentrations in the case of the autumn sample. For both sutherlandioside B (summer: 3.01 &plusmn / 7.19 mg/ml / autumn: 2.15 &plusmn / 7.19 mg/ml / winter: 2.89 &plusmn / 7.19 mg/ml / spring: 1.47 &plusmn / 7.19 mg/ml) and D (summer: 5.82 &plusmn / 14.48 mg/ml / autumn: 3.33 &plusmn / 14.48 mg/ml / winter: 4.23 &plusmn / 14.48 mg/ml / spring: 2.50 &plusmn / 14.48 mg/ml) show significantly (P &lt / 0.0001) higher concentrations in the case of the autumn sample. For the summer&nbsp / leaf/stem comparison, results show that for sutherlandin A (leaf: 3.67 &plusmn / 8.18 mg/ml / stem: 4.67 &plusmn / 8.18 mg/ml) show significantly (P &lt / 0.0001) higher concentrations in the case of the stem&nbsp / sample. For the sutherlandin D (leaf: 4.10 &plusmn / 4.81 mg/ml / stem: 3.31 &plusmn / 4.81 mg/ml) show significantly (P &lt / 0.0001) higher concentrations in the case of the summer leaf sample. For both the&nbsp / sutherlandioside B (leaf: 3.01 &plusmn / 4.24 mg/ml / stem: 3.62 &plusmn / 4.24 mg/ml) and D (leaf: 5.82 &plusmn / 0.42 mg/ml / stem: 5.80 &plusmn / 0.42 mg/ml) show significantly (P &lt / 0.0001) higher concentrations in the&nbsp / case of the stem samples. Results demonstrate that the production of secondary metabolites are influenced by&nbsp / &nbsp / environmental factors like seasonal harvesting, as indicated by the variation in the chemical constituent composition of Lessertia frutescens depending on the season collected in. Moreover, the storage of Lessertia frutescens for a period of one year resulted in an&nbsp / increase of two of the four constituents being monitored. There was slight variations in the chemical constituents, depending on whether the leaf or stem material of Lessertia frutescens was being used. Finally, the type of chemical constituent being monitored was also important in the consideration of this study. Therefore, this study can be seen as a starting point to further&nbsp / &nbsp / investigations of these aspects, which are of clinical, pharmacological and economic</p>
4

The impact of storage time and seasonal harvesting on biomarker levels of lessertia frutescens

Campbell, James January 2012 (has links)
>Magister Scientiae - MSc / In South Africa, it is estimated that approximately 70% of the population frequently make use of traditional medicinal plants for their health care needs. The use of Lessertia frutescens by the various cultural groups in South Africa dates back to the earlier civilizations and continues to be used today to treat a multitude of ailments. To get the best results from a medicinal plant, one would need to ensure that the crude material is of good quality through interventions like being properly grown, well dried and correctly processed. This would add a measure of quality assurance, which will contribute towards the safety and efficacy aspect of herbal medicine. The aim of this study was to investigate what impact a particular season of harvest and the time in storage would have on the flavonoid and triterpenoid marker levels of Lessertia frutescens. To achieve this, the following was investigated: (1) storage variation of Lessertia frutescens leaves by comparing the results obtained from the High Performance Liquid Chromatography (HPLC) analysis of the flavonoids and triterpenoids, (2) seasonal variation of Lessertia frutescens leaves by comparing the results obtained from the HPLC analysis of the flavonoids and triterpenoids, (3) leaf and stem variation of Lessertia frutescens by comparing the results obtained from HPLC analysis of the flavonoids and triterpenoids. The hypotheses were: (1) the stored sample would indicate the same level of the biomarkers for the flavonoids and triterpenoids, as that of the freshly prepared sample, (2) the sample that was harvested during the summer season would indicate higher levels of the biomarkers of flavonoids and triterpenoids than the other three seasons, (3) the leaf sample would indicate the same level of the biomarkers for the flavonoids and triterpenoids, as that of the stem sample. An Agilent 1200 series HPLC was used for the determination of the flavonoids sutherlandin A and sutherlandin D as well as the triterpenoids sutherlandioside B and sutherlandioside D. Results show that for both sutherlandin A (summer: 3.67 ± 2.88 mg/ml; storage: 4.07 ± 2.88 mg/ml) and D (summer: 4.10 ± 1.06 mg/ml; storage: 4.25 ± 1.06 mg/ml) show significantly (P < 0.0001) higher concentrations in the case of the storage samples. For both sutherlandioside B (summer: 3.01 ± 0.39 mg/ml; storage: 2.82 ± 0.39 mg/ml) and D (summer: 5.82 ± 0.42 mg/ml; storage: 4.66 ± 0.42 mg/ml) show significantly (P < 0.0001) higher concentrations in the case of the fresh summer samples. For the seasonal comparison, results show that for sutherlandin A (summer: 3.67 ± 12.49 mg/ml; autumn: 4.75 ± 12.49 mg/ml; winter: 4.23 ± 12.49 mg/ml; spring: 6.56 ± 12.49 mg/ml) show significantly (P < 0.0001) higher concentrations in the case of the spring sample. For sutherlandin D (summer: 4.10 ± 10.32 mg/ml; autumn: 6.37 ± 10.32 mg/ml; winter: 5.25 ± 10.32 mg/ml; spring; 6.08 ± 10.32 mg/ml) show significantly (P < 0.0001) higher concentrations in the case of the autumn sample. For both sutherlandioside B (summer: 3.01 ± 7.19 mg/ml; autumn: 2.15 ± 7.19 mg/ml; winter: 2.89 ± 7.19 mg/ml; spring: 1.47 ± 7.19 mg/ml) and D (summer: 5.82 ± 14.48 mg/ml; autumn: 3.33 ± 14.48 mg/ml; winter: 4.23 ± 14.48 mg/ml; spring: 2.50 ± 14.48 mg/ml) show significantly (P < 0.0001) higher concentrations in the case of the autumn sample. For the summer leaf/stem comparison, results show that for sutherlandin A (leaf: 3.67 ± 8.18 mg/ml; stem: 4.67 ± 8.18 mg/ml) show significantly (P < 0.0001) higher concentrations in the case of the stem sample. For the sutherlandin D (leaf: 4.10 ± 4.81 mg/ml; stem: 3.31 ± 4.81 mg/ml) show significantly (P < 0.0001) higher concentrations in the case of the summer leaf sample. For both the sutherlandioside B (leaf: 3.01 ± 4.24 mg/ml; stem: 3.62 ± 4.24 mg/ml) and D (leaf: 5.82 ± 0.42 mg/ml; stem: 5.80 ± 0.42 mg/ml) show significantly (P < 0.0001) higher concentrations in the case of the stem samples.Results demonstrate that the production of secondary metabolites are influenced by environmental factors like seasonal harvesting, as indicated by the variation in the chemical constituent composition of Lessertia frutescens depending on the season collected in. Moreover, the storage of Lessertia frutescens for a period of one year resulted in an increase of two of the four constituents being monitored. There was slight variations in the chemical constituents, depending on whether the leaf or stem material of Lessertia frutescens was being used. Finally, the type of chemical constituent being monitored was also important in the consideration of this study. Therefore, this study can be seen as a starting point to further investigations of these aspects, which are of clinical, pharmacological and economic importance.

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