Marketed natural products are usually a complex admixture of phytoconstituents which also can vary depending on the method of preparation or the source of material used. Such variability can impact the interpretation of in vitro, non-clinical in vivo and/or clinical studies where natural products are tested, leading to irreproducible and difficult to interpret results. Therefore, selection and authentication of botanical material and identification of key biologically active compounds present within marketed natural products is fundamental to the sourcing process. The NaPDI Analytical Core has established reference standard specifications and developed appropriate approaches to assess the content and quality of natural product precipitant formulations used in research studies, and more precisely for in vitro and in vivo assessment of natural product-drug interactions. This is represented in the diagram below where all recommended steps to select a natural product are detailed chronologically, constituting an easy to use tool for the researcher with detailed consideration of each step.
Figure. Recommended steps in the selection of botanical natural products for research purposes (in vitro and/or in vivo studies), and important questions for consideration with each step.
Selection and characterization of botanical natural products for research studies: a NaPDI center recommended approach. Kellogg JJ, Paine MF, McCune JS, Oberlies NH, Cech NB. Nat Prod Rep. 2019 Jan 25. doi: 10.1039/c8np00065d.