A study conducted by a team of scientists from the University of Johannesburg in partnership with the Pacific Northwest National Laboratory (USA), has proposed a reliable method for the accurate identification and differentiation of plant derived natural products, based on an ion mobility spectrometry-mass spectrometry (IMS-MS).
The researchers said accurate identification and differentiation at the stereochemistry level remained a bottleneck in natural products or metabolomics studies, explaining that such metabolites were chlorogenic acids that are plant metabolites with various biological properties. “These compounds are naturally synthesized with trans configuration but after UV exposure, their configuration changes to cis. Recently, these isomers were shown to bind differently on the HIV-1 integrase enzyme thereby halting potential HIV infection. Determining the most active isomer is of paramount importance, when identifying these natural products.”
They said since the discovery of these isomers in the late 70s, there was no single analytical platform capable of distinguishing between CGA isomers with high degree of certainty. The multi-dimensionality of the plant metabolome – reflected also by the chemical and structural complexity and diversity of these plant metabolites – posed an immense challenge to the current analytical platforms, in natural product-related studies.
For the first time, using combination of advanced computational modelling and experimental IMS-MS methods in the study, all these isomers were accurately and differentially identified. The study appeared in the prestigious Journal of Physical Chemistry Letters (JPCL) that is published by the American Chemical Society (http://pubs.acs.org/doi/abs/10.1021/acs.jpclett.6b03015).
“In nutshell, this approach and findings will be extremely important for drug discovery studies and could be adapted to other bio-molecules,’ said Dr Edwin Madala who led UJ’s team of researchers. Dr Erin Barker led the Pacific Northwest National Laboratory team.