Pharmacognostic Evaluation and Quality Control Parameters of Andrographis Paniculata

Andrographis paniculata (Burm. f.) Nees, known as kalmegh, is a widely used bitter herb in Ayurvedic, Chinese and Southeast Asian practice, yet commercial lots vary considerably in quality. This review, which reports no new data, brings together published work on the pharmacognostic evaluation of the leaf and aerial parts: botanical identity, macroscopic and microscopic features, physicochemical limits, phytochemical screening and chromatographic standardisation by andrographolide content. It also considers contaminants, adulteration, stability and the link between measured parameters and biological activity. The literature supports a workable set of identity, purity and assay tests, but reported ranges differ with origin, harvest stage and method, and few limits have been confirmed in collaborative studies.