Cytotoxic activity of marine sponge extracts from the sub-Antarctic Islands and the Southern Ocean
- Olsen, Elisabeth, De Cerf, Christopher, Dziwornu, Godwin, Puccinelli, Eleonora, Parker-Nance, Shirley, Ansorge, Isabelle J, Samaai, Toufiek, Dingle, Laura, Edkins, Adrienne L, Sunassee, Suthananda N
- Authors: Olsen, Elisabeth , De Cerf, Christopher , Dziwornu, Godwin , Puccinelli, Eleonora , Parker-Nance, Shirley , Ansorge, Isabelle J , Samaai, Toufiek , Dingle, Laura , Edkins, Adrienne L , Sunassee, Suthananda N
- Date: 2016
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/66300 , vital:28931 , https://doi.org/10.17159/sajs.2016/20160202
- Description: publisher version , Over the past 50 years, marine invertebrates, especially sponges, have proven to be a valuable source of new and/or bioactive natural products that have the potential to be further developed as lead compounds for pharmaceutical applications. Although marine benthic invertebrate communities occurring off the coast of South Africa have been explored for their biomedicinal potential, the natural product investigation of marine sponges from the sub-Antarctic Islands in the Southern Ocean for the presence of bioactive secondary metabolites has been relatively unexplored thus far. We report here the results for the biological screening of both aqueous and organic extracts prepared from nine specimens of eight species of marine sponges, collected from around Marion Island and the Prince Edward Islands in the Southern Ocean, for their cytotoxic activity against three cancer cell lines. The results obtained through this multidisciplinary collaborative research effort by exclusively South African institutions has provided an exciting opportunity to discover cytotoxic compounds from sub-Antarctic sponges, whilst contributing to our understanding of the biodiversity and geographic distributions of these cold-water invertebrates. Therefore, we acknowledge here the various contributions of the diverse scientific disciplines that played a pivotal role in providing the necessary platform for the future natural products chemistry investigation of these marine sponges from the sub- Antarctic Islands and the Southern Ocean. Significance: This study will contribute to understanding the biodiversity and geographic distributions of sponges in the Southern Ocean. This multidisciplinary project has enabled the investigation of marine sponges for the presence of cytotoxic compounds. Further investigation will lead to the isolation and identification of cytotoxic compounds present in the active sponge extracts. , University of Cape Town; South African Medical Research Council; National Research Foundation (South Africa); CANSA; Rhodes University; Department of Science and Technology; Department of Environmental Affairs; SANAP
- Full Text:
- Date Issued: 2016
- Authors: Olsen, Elisabeth , De Cerf, Christopher , Dziwornu, Godwin , Puccinelli, Eleonora , Parker-Nance, Shirley , Ansorge, Isabelle J , Samaai, Toufiek , Dingle, Laura , Edkins, Adrienne L , Sunassee, Suthananda N
- Date: 2016
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/66300 , vital:28931 , https://doi.org/10.17159/sajs.2016/20160202
- Description: publisher version , Over the past 50 years, marine invertebrates, especially sponges, have proven to be a valuable source of new and/or bioactive natural products that have the potential to be further developed as lead compounds for pharmaceutical applications. Although marine benthic invertebrate communities occurring off the coast of South Africa have been explored for their biomedicinal potential, the natural product investigation of marine sponges from the sub-Antarctic Islands in the Southern Ocean for the presence of bioactive secondary metabolites has been relatively unexplored thus far. We report here the results for the biological screening of both aqueous and organic extracts prepared from nine specimens of eight species of marine sponges, collected from around Marion Island and the Prince Edward Islands in the Southern Ocean, for their cytotoxic activity against three cancer cell lines. The results obtained through this multidisciplinary collaborative research effort by exclusively South African institutions has provided an exciting opportunity to discover cytotoxic compounds from sub-Antarctic sponges, whilst contributing to our understanding of the biodiversity and geographic distributions of these cold-water invertebrates. Therefore, we acknowledge here the various contributions of the diverse scientific disciplines that played a pivotal role in providing the necessary platform for the future natural products chemistry investigation of these marine sponges from the sub- Antarctic Islands and the Southern Ocean. Significance: This study will contribute to understanding the biodiversity and geographic distributions of sponges in the Southern Ocean. This multidisciplinary project has enabled the investigation of marine sponges for the presence of cytotoxic compounds. Further investigation will lead to the isolation and identification of cytotoxic compounds present in the active sponge extracts. , University of Cape Town; South African Medical Research Council; National Research Foundation (South Africa); CANSA; Rhodes University; Department of Science and Technology; Department of Environmental Affairs; SANAP
- Full Text:
- Date Issued: 2016
Land acquisition for and local livelihood implications of biofuel development in Zimbabwe
- Authors: Thondhlana, Gladman
- Date: 2016
- Subjects: Biomass energy -- Government policy -- Zimbabwe Biomass energy -- Economic aspects -- Zimbabwe Biomass energy -- Environmental aspects -- Zimbabwe
- Language: English
- Type: text
- Identifier: http://hdl.handle.net/10962/49940 , vital:25944
- Description: In recent years, proponents of 'green and clean fuel' have argued that the costs of overreliance on fossil fuels could be reduced through transition to biofuels such as bio-ethanol. Global biofuel discourses suggest that any transition to biofuel invariably results in significant benefits, including energy independence, job creation, development of agro-industrial centres at local level and high revenue generations for the state with minimum negative impacts on the environment. With many risks and costs associated with traditional 'dirty' fuels, it is likely that many countries, particularly African countries, will move towards the 'green and clean fuel' alternative. However, until recently research has arguably paid limited attention to the local livelihood impacts related to land acquisition for biofuel development or the policy frameworks required to maximise biofuel benefits. With regards to biofuel benefits, some recent studies suggest that the much bandied potential for greater tax revenue, lowered fuel costs and wealth distribution from biofuel production have all been perverted with relatively little payoff in wage labour opportunities in return (e.g. Richardson, 2010; Wilkinson and Herrera, 2010). Based on work done in Chisumbanje communal lands of Zimbabwe (Thondhlana, 2015), this policy brief highlights the local livelihood impacts of biofuel development and discusses policy implications of the findings. By highlighting the justifications of biofuel development at any cost by the state, the study sheds some light on the conflicts between state interests and local livelihood needs.
- Full Text:
- Date Issued: 2016
- Authors: Thondhlana, Gladman
- Date: 2016
- Subjects: Biomass energy -- Government policy -- Zimbabwe Biomass energy -- Economic aspects -- Zimbabwe Biomass energy -- Environmental aspects -- Zimbabwe
- Language: English
- Type: text
- Identifier: http://hdl.handle.net/10962/49940 , vital:25944
- Description: In recent years, proponents of 'green and clean fuel' have argued that the costs of overreliance on fossil fuels could be reduced through transition to biofuels such as bio-ethanol. Global biofuel discourses suggest that any transition to biofuel invariably results in significant benefits, including energy independence, job creation, development of agro-industrial centres at local level and high revenue generations for the state with minimum negative impacts on the environment. With many risks and costs associated with traditional 'dirty' fuels, it is likely that many countries, particularly African countries, will move towards the 'green and clean fuel' alternative. However, until recently research has arguably paid limited attention to the local livelihood impacts related to land acquisition for biofuel development or the policy frameworks required to maximise biofuel benefits. With regards to biofuel benefits, some recent studies suggest that the much bandied potential for greater tax revenue, lowered fuel costs and wealth distribution from biofuel production have all been perverted with relatively little payoff in wage labour opportunities in return (e.g. Richardson, 2010; Wilkinson and Herrera, 2010). Based on work done in Chisumbanje communal lands of Zimbabwe (Thondhlana, 2015), this policy brief highlights the local livelihood impacts of biofuel development and discusses policy implications of the findings. By highlighting the justifications of biofuel development at any cost by the state, the study sheds some light on the conflicts between state interests and local livelihood needs.
- Full Text:
- Date Issued: 2016
Pessimistic assessment of white shark population status in South Africa: comment on Andreotti et al.(2016)
- Irion, Dylan T, Noble, Leslie R, Kock, Alison A, Gennari, Enrico, Dicken, Matthew L, Hewitt, Adrian M, Towner, Alison V, Booth, Anthony J, Smale, Malcolm J, Cliff, Geremy
- Authors: Irion, Dylan T , Noble, Leslie R , Kock, Alison A , Gennari, Enrico , Dicken, Matthew L , Hewitt, Adrian M , Towner, Alison V , Booth, Anthony J , Smale, Malcolm J , Cliff, Geremy
- Date: 2017
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/${Handle} , vital:35799 , https://doi.10.3354/meps12283
- Description: Andreotti et al. (2016; Mar Ecol Prog Ser 552:241−253) estimate an abundance (N) of 438 white sharks Carcharodon carcharias and a contemporary effective population size (CNe) of 333 individuals along the South African coast. N was estimated by using a mark-recapture analysis of photographic identification records from a single aggregation site (Gansbaai). CNe was calculated based on the levels of pairwise linkage disequilibrium of genetic material collected from 4 aggregation sites across approximately 965 km of South African coastline. However, due to the complex stock structure of white sharks and the model assumptions made by Andreotti et al. (2016), the conclusions drawn cannot be supported by their methods and data.
- Full Text:
- Date Issued: 2017
- Authors: Irion, Dylan T , Noble, Leslie R , Kock, Alison A , Gennari, Enrico , Dicken, Matthew L , Hewitt, Adrian M , Towner, Alison V , Booth, Anthony J , Smale, Malcolm J , Cliff, Geremy
- Date: 2017
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/${Handle} , vital:35799 , https://doi.10.3354/meps12283
- Description: Andreotti et al. (2016; Mar Ecol Prog Ser 552:241−253) estimate an abundance (N) of 438 white sharks Carcharodon carcharias and a contemporary effective population size (CNe) of 333 individuals along the South African coast. N was estimated by using a mark-recapture analysis of photographic identification records from a single aggregation site (Gansbaai). CNe was calculated based on the levels of pairwise linkage disequilibrium of genetic material collected from 4 aggregation sites across approximately 965 km of South African coastline. However, due to the complex stock structure of white sharks and the model assumptions made by Andreotti et al. (2016), the conclusions drawn cannot be supported by their methods and data.
- Full Text:
- Date Issued: 2017
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