It has been estimated that around 80% of the population in developing countries rely on plant-derived medicines or traditional herbal remedies. But is there science to support this form of treatment? African medicinal plants, as a source of new drugs, are understudied considering the high percentage of plants not yet screened. The previously known University of Pretoria Botany Department has moved in this direction in more ways than one. The faculty has changed their name to Department of Plant Science, expanded into biotechnology and medicinal plant science, and physically moved into the Plant Science Complex, the “greenest” building on campus in January this year.
Working in collaboration with universities in Switzerland, Japan, The Netherlands etc. means that protocol used to analyse samples need to deliver on international standards. Therefore quick reliable methodology that removes any human error is paramount at Plant Science. The Buchi SpeedExtractor is one such example of new equipment purchased in order to follow this strict protocol. All plants produce chemical compounds as part of their normal metabolic activities. This includes primary metabolites found in all plants, and secondary metabolites found in a particular genus or species. It is these secondary metabolites and pigments that can have therapeutic actions in humans, and which can be refined to produce drugs efficient to work as phytomedicines. The SpeedExtractor is used for extracting the secondary metabolites from South African plants in order to identify new active principals that could help in the treatment of many diseases such as malaria, AIDS and various cancers.
Normally pressurised extraction can be very time consuming. The Buchi SpeedExtractor extracts up to 6 samples simultaneously in 20 – 40 minutes, allowing for high levels of efficiency and throughput. It also distinguishes itself by its user-friendliness and flexibility, which comes in handy since the unit is used by researchers and post graduate students alike for a variety of extractions. The desired method is loaded, then extraction cells are sealed automatically, and at the push of a button, six samples are extracted – no error-prone sealing, no time consuming programming. The SpeedExtractors flexibility is also unique in that temperature range stretches from 50 – 200°C and pressure ranges of 50 – 150 bar. There are many extraction cell sizes and volumes to choose from. An integrated flushing process into a separate vessel also makes the cleaning process easier.
One of the main aims at U.P. Pant Science is to scientifically validate traditional claims and healing plant stories/theories, some of which have been passed from generation to generation. 250 000 plant species exist in the world and SA has 10% of these species making us the third most flora diverse country in the world. In the Botanical Garden at UP one can find more species than in the UK, and a library of 100 000 collected plant samples already exists in the herbarium. A whole range of well-known cancer chemotherapeutic drugs are derived from secondary metabolites, and the research team at UP are now also investigating a family of compounds relating to pain applications and nausea that helps alleviate the side-effects of chemotherapy. The department are also conducting extensive research on the control / eradication of malaria. Research in the Department of Plant Science also involves tests against bacteria, viruses, TB, mycotoxins in food crops, and vegetation dynamics in areas such as the wetlands, Namaqualand and Kalahari.