Researchers from Sechenov University, Russia, and La Trobe University, Australia, have designed a fast and cost-effective method of detecting and identifying bioactive compounds in complex samples such as plant extracts. Their research is published in Applied Sciences, Journal of Pharmaceutical and Biomedical Analysis and Journal of Chromatography A. The research team studied plant extracts using bioassay and thin-layer chromatography, enabling scientists to investigate a variety of compounds found in your garden. Using this method combination, scientists examined the properties of bioactive compounds from culinary herbs commonly used in the Mediterranean diet (basil, lavender, rosemary, oregano, sage, and thyme) and Australia's native plants (lemon myrtle, native thyme, sea parsley, seablite and saltbush).
Some of the secondary metabolites from these plants exhibited significant antioxidant activity and enzyme inhibition, like α-amylase inhibition. This suggests that many garden variety herbs may be preventive not only against cardiovascular diseases but also type 2 diabetes. For example, enzyme α-amylase breaks down polysaccharides, increasing blood sugar levels. Recent studies suggest that hyperglycemia induces the generation of reactive oxygen species, alteration of endogenous antioxidants, and oxidative stress.
Using the researcher’s method, the combination of TLC chromatography with microbial (bacteria and yeast) tests and biochemical (enzyme) bioassays enables the rapid and reliable characterization of bioactive compounds directly on the chromatographic plates, without isolation/extraction. Perhaps the greatest advantage of HPTLC is that plates/chromatograms can be directly immersed into enzyme solution (bioassays), incubated for up to several hours, followed by visualization of the (bio)activity profile via an enzyme-substrate reaction as bioactivity zones. This streamlines detection and characterization capabilities while promoting cost-effectiveness.