When medicinal plants are extracted, using either traditional or contemporary methods, the choice of technique can produce metabolic artifacts. The supplement industry currently is unable to assess whether an extraction method alters metabolite ratios found in the raw plant material. Additionally, assessment of homogeneity of the ground material is an important uncertainty measurement necessary for consistent and predictable product manufacture.
The ecological impact of growing conditions on medicinally complex metabolite ratios in plants, such as ginseng or black cohosh, plays an important role in defining the quality of herbal products. Several earlier posts describe the impact of rhizosphere fungi on the formation of active compounds in plant roots (here, here and here). Since plant root cell colonization by mycorrhizal fungi across the plant root system is asynchronous, extraction data often reflects mean value metabolite formation.
Analysis of isoflavonoid formation in various sections and cells of black cohosh root might provide information about the role of mycorrhizal fungi in altering root secondary metabolites as a result of symbiosis. Currently no analytical technique provides real time mapping of spatial and/or temporal changes in plant root cells in response to the presence of mycorrhizal fungi.
At one point I briefly pursued the idea of using Raman spectroscopy to provide information on the chemical composition of the material under analysis. However, the technique struggled with background interference from fluorescence, as well as thermal and photochemical degradation of plant cell structures.
A recent methodological development, reported in Nature Scientific Reports, captured images of recently synthesized, deuterium-labeled lipids in mice tumors. Scientists, then analyzed a series of these tumor sections with mass spectrometry to produce “movie frame” images capable of indicating metabolic turnover. Certainly an improvement, but not yet capable of real time analysis.