ABSTRACT
The main purpose of markers of characteristic constituents is the identification and quantification of herbal materials in herbal preparations and finished herbal products. Markers used as chemical reference substances should be international chemical or pharmacopoeial reference substances. If others are used, markers for quantitative determination should be of high purity as required by national regulations, determined by validated analytical methods, including physical and chemical ones. Marker substances for toxic constituents are used to define maximum acceptable concentrations of toxic constituents in herbal materials, herbal preparations or finished herbal products. Valtrate in Valeriana wallichii is its marker compound, but it degrades at high temperature. It becomes a problem for herbal drug preparations that go through high temperature, and also in its course of stability study. Polyherbal formulations which contain a large number of herbs along with high percentage of sugar make it difficult for an analyst to extract the desired compound.
