DETERIORATION OF HERBAL DRUGS

Besides being adulterated by different means as discussed earlier, the crude drugs are prone to deterioration on storage. The shelf-life of crude drugs are influenced by many factors which include not only the quality of storage conditions but also the stability of the secondary (2°) metabolites present therein. Several factors are to be considered for the detrimental effects on the stored products.
•Primary Factors for Deterioration
Several environmental factors relating to storage e.g. light, humidity, oxygen, temperature etc. can produce detrimental effects on stored products, but more deterioration usually results from a combination of these factors, which leads to the development of living organism including molds, mites, bacteria etc. The primary factors leading to the deterioration can be summarized as follows:
1- Light
•Photo-decomposition occurs with santonin, the principal constituents of wormseed, which on exposure to light darkens and eventually becomes black. In general, drugs should be protected by suitable light-proof wrapping or by the use of amber color containers. Powdered rhubarb stored in clear glass jars rapidly changes as the exposed surfaces turning from yellow to more reddish color.