Plants defend themselves from other organisms by elaborating bioactive chemical defences. This is the essential basis of the use of herbal medicines that still represents a major therapeutic resort for much of humanity However, at the outset, it must be stated that any plant that is not part of our evolved dietary cultures is potentially dangerous. Commercial herbal medicinal preparations approved by expert regulatory authorities have a significant place in mainstream conventional medicine and in complementary medicine. The first and last message of this book on the biochemical targets of bioactive plant constituents is that use of herbal preparations for medicinal purposes should only occur subject to expert.
