Determination and importance of trace elements in chinese medicinal herbs used for healthcare and medical treatments

One of the first forms of biofortification was the use of herbal-type crops. For over 4000 years, the Chinese people have effectively used medicinal herbs for medical treatments, including use as diuretics, pain relievers, health additives, and to relieve stasis (Ou 1993; Yen 1980). The therapeutic effect of Chinese medicinal herbs depends on their chemical constituents, most of which are organic compounds and trace elements that are key components of an essential enzyme system or other proteins (Mutaftchiev and Tzachev 2003). Many studies on the contents of trace elements in these herbs have been published (Chen and ChangLai 2001; Wang et al. 1996; Chen et al. 1993; Liu et al. 1991; Ou 1993; Chiao 1992; Chen and Lin 1988; Yen 1980). The roles of trace elements, iodine (I), iron (Fe), and zinc (Zn), are of particular interest to scientists in Chinese medicine. For example, I is known as an essential nutrient for humans, and it participates in the synthesis of thyroid hormones (Underwood 1973), whereas deficiencies of Fe and Zn have been associated with depressed growth and poor health in Taiwanese children. Apparently, some diseases are clearly associated with deficiencies of trace elements in the human body. In addition, the levels of toxic elements such as arsenic (As), antimony (Sb), and samarium (Sm) in Chinese medicinal herbs are also of prime interest in toxicological studies, in addition to their possible roles in human health (Ou 1993; Mertz 1981; Yen 1980).