147 research outputs found
Ten years of marine natural products research at Rhodes University
Marine invertebrates, algae and microorganisms produce a plethora of structurally unique and biologically active secondary metabolites. The ecological roles of these natural products, although not completely understood, range from chemical defence against predation to intra-specific cues for larval settlement. Surprisingly, a number of these metabolites have also shown potential as new medicines for the treatment of a variety of diseases including cancer. The natural products chemistry of southern Africa’s unique marine flora and fauna is relatively unknown and this review provides an overview of the contribution made by the marine natural products research group at Rhodes University to the isolation, identification and synthesis of biologically active natural products from southern African marine microorganisms, algae, sponges, ascidians, soft corals and molluscs
The myriad positive impacts of the Virtual Learning Environment, from LabSims to Smart Worksheets (a 17 year journey)
PROBLEM
Introducing a virtual learning environment (VLE) in support of practical teaching in Chemistry is not trivial. In this study we identify keys areas which are essential for successful implementation based on 17 years of experience.
PLAN
We have analysed a range of metrics from first initiating a VLE in the Centre for Excellence in Teaching and Learning (CETL) called Bristol CemLabS in 2006 and compare and contrast a similar implementation in the Faculty of Natural Sciences at The University of the Western Cape in South Africa in 2020.
ACTION
There are strong similarities in both environments following implementation of a VLE. Raising of confidence of students in using instruments and carrying out techniques found in an undergraduate chemistry laboratory is clear, increasing students understanding of the theory behind techniques and their real appreciation of health and safety. For demonstrators, their role changes from one where they are giving instruction to one where they are discussing the development of the practical investigation with the students. For academics, the transformation in ability of students, and long-term impacts on practical ability and final year projects that can be undertaken are noted.
REFLECTION
The transformation in both case studies was pretty much instant and irreversible for the students. Key elements required are strong IT support, strong collaboration between staff, demonstrators and technical staff. The main question to ask is why did we take so long to do this
Anti-oesophageal cancer activity in extracts of deep-water Marion Island sponges
OESOPHAGEAL CANCER IS ONE OF THE most common causes of cancer-related deaths in South African black males. The limited efficacy of chemotherapeutic agents to treat this disease has prompted a search for potential new chemical entities with anticancer properties. We report here on the evidence for anti-oesophageal cancer activity in the methanolic extracts of five species of sponges dredged from a depth of approximately 100 m in the vicinity of Marion Island in the Southern Ocean during the autumn of 2004
Hyphenated LC-ICP-MS/ESI-MS identification of halogenated metabolites in South African marine ascidian extracts
Extracts of 13 species of marine ascidian collected in Algoa Bay were analyzed by LC-ICP-MS/ESI-MS. This technique allows
parallel analysis of the molecular species and the presence of certain elements. The LC-ICP-MS/ESI-MS technique was used to
target iodinated metabolites in this study. Three ascidian species afforded the known 3,5–diiodo-4-methoxyphenethylamine
(12), which was confirmedby the isolation of this metabolite fromAplidium monile.MS also suggested the presence of theknown
3,5–dibromo-4-methoxyphenethylamine (10) and the new 3-bromo-5–iodo-4-methoxyphenethylamine (11) in the A. monile
extract. The presence of the known 3,5-dibromotetramethyltyrosine (21) and the new 3-iodotetramethyltyrosine (23) in extracts
of an unidentified Didemnum species was similarly proposed from MS evidence. This is the first report of the occurrence of
iodinated metabolites in South African marine invertebrates.IS
Flipping the thinking on equality, diversity, and inclusion. why EDI is essential for the development and progression of the chemical sciences: A case study approach
All learners have a contribution to make to the development of the Chemical Sciences, be that in novel ways to teach, and their perspectives and contexts, but also in research, both in chemical education and the wider Chemical Sciences. Through four case studies, this paper explores interactions with diverse groups and how this has altered perspectives on both teaching and research. The case studies include work with visually impaired adults, a project bringing together First Peoples in Australia with academics to explore old ways (traditional science) and new ways (modern approaches), primary (elementary) school perspectives on teaching science, and a project in South Africa to connect university and township communities. Not only do these case studies demonstrate the immense value these diverse groups bring to our understanding about how to learn, but they also bring new perspectives on how to view and solve chemical problems
Halogenated oxindole and indoles from the South African marine ascidian Distaplia skoogi:
The known 3,6-dibromoindole (1), 6-bromo-3-chloroindole (2) and 6-bromo-2-oxindole (3) were isolated from the marine ascidian (sea squirt) Distapia skoogi collected from Algoa Bay, South Africa. Standard spectroscopic techniques were used to elucidate the structures of 1-3. All three compounds were found to be moderately cytotoxic to metastatic MDA-MB-231 breast cancer cells
The origin of the matter-antimatter asymmetry
Although the origin of matter-antimatter asymmetry remains unknown,
continuing advances in theory and improved experimental limits have ruled out
some scenarios for baryogenesis, for example the sphaleron baryogenesis at the
electroweak phase transition in the standard model. At the same time, the
success of cosmological inflation and the prospects for discovering
supersymmetry at the LHC have put some other models in sharper focus. We review
the current state of our understanding of baryogenesis with the emphasis on
those scenarios that we consider most plausible.Comment: submitted to Reviews of Modern Physics; 38 pages; 9 figure
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