Metabolomics Research at Tshwane University of Technology (TUT)
The Phytochemistry Group, within the Department of Pharmaceutic Sciences, has, over the past few years, followed a metabolic approach to identifying chemical markers that can be used for the quality control of herbal drugs. This is mostly done through chemometric analysis of aligned ultra-performance liquid chromatography-mass spectrometry (UPLC-MS) data obtained through the analysis of a large number of sample extracts.
The aim is to obtain an overview of the degree of natural variation in the chemistry and to identify chemotypes within the populations. The efficacy of the samples as antibacterial, antifungal, anti-inflammatory or anxiolytic agents can then be linked to the chemistry of the extracts.
More recently, the group has also been involved in nuclear magnetic resonance (NMR) metabolomics and even high-performance thin layer chromatography metabolomics using the rTLC online platform. The identified chemical markers can be isolated from the plant material, structurally elucidated and quantitatively determined in the plant samples to prove that they are robust markers for the species or groupings.
In light of the stricter regulation of herbal drugs imposed by the South African Health Products Regulatory Authority (SAHPRA), it is a matter of urgency that markers be identified that can be used for quality control purposes. High quality (safe, effective and consistent) herbal products ensure sustainable commercialisation. Prof. Alvaro Viljoen heads the group, while Dr. Maxleene Sandasi, Dr. Ilze Vermaak and Prof. Sandra Combrinck are all involved in these initiatives.
The Department of Chemistry has focused on phytoremediation and agricultural application of metabolomic profiling. Professor Ntebogeng Mokgalaka leads a research group which studies the response of plants to abiotic stresses including metals, salinity and drought.The objectives include elucidating the mechanisms of stress tolerance employed by plants, profiling secondary metabolites of stressed plants, testing the efficacy of extracts obtained from stressed plants, identifying, isolating and elucidating the structures of novel compounds in stressed plants that can be used as leads for new drugs and pharmaceuticals.
Dr. Wilma Augustyn and her group focus on plant-insect and plant-pathogen interactions. In the light of the constraints placed on the use of pesticides and fungicides, novel methods of pest management must be implemented in the agricultural sector. Chemometric and multivariate data analysis identify biomarkers that contribute to resistance or tolerance to insect predation and pathogen infection of various South African fruit crops.