ABSTRACT

Since ancient times people have used plant resources for different needs including food, housing construction, clothing, cosmetics, cultural, and medicinal purposes. Medicinal plants play an important if not one of the central roles among these uses. The number of plant species have been used or are still used for health improvement purposes can be approximately estimated as more than 70,000 (17%) out of the 422,000 flowering plant species. The number of commercialized species was assessed as approximately 3000 [1]. The evaluation of commercially traded amounts of medicinal plants reveals the dominance of developing countries in export; China alone has exported near to 140,000 tonnes of plant material worth of $300 million between 1991 and 1998 [2].