Development of Natural Medicines and Their Application in Chemical Evaluation a Critical Review of Extraction, Analytical Profiling and Quality Standardisation

Abstract

Natural medicines remain a major source of therapeutic leads and of widely used traditional remedies, but their multi-component nature makes development and quality control more demanding than for single synthetic drugs. This review follows the path from plant selection to a chemically defined, standardised medicine and focuses on the role of chemical evaluation at every step: authentication, extraction, isolation, profiling, quantification and validation. Three analyses support the discussion. First, a chemical-space map of sixteen well-known natural-product drugs, calculated from molecular formulas, shows that four of them (paclitaxel, reserpine, vinblastine and digoxin) exceed the molecular-weight or hydrogen-bond-acceptor limits of the rule of five, which has implications for formulation and analysis. Second, qualitative comparisons rank six extraction techniques and six analytical platforms against practical criteria. Third, a simulated chromatographic-fingerprint example illustrates how a cosine-similarity metric separates a conforming batch (0.9995) from a degraded or adulterated one (0.7815). Requirements for method validation, contaminant control, safety, interactions and regulatory pathways through 2023 are summarised, and priorities for future work—orthogonal analytics, data-driven dereplication and biotechnological supply—are identified.

Index Terms—natural medicines, phytochemical analysis, extraction, HPLC, mass spectrometry, NMR, chromatographic fingerprint, standardisation, method validation