L. G. Valerio, Jr.1 , G. F. Gonzales2 , 1Office of Food Additive Safety, CFSAN, FDA, College Park, MD, 2Department of Biological and Physiological Sciences, Universidad Peruana Cayetano Heredia, Lima, Peru
Natural products have played a significant role in drug discovery and development especially for agents against cancer and infectious disease. For example, an analysis of new and approved drugs for cancer by the United States Food and Drug Administration over the period of 1981-2002 showed that 62% of these cancer drugs were of natural origin. Natural compounds possess highly diverse and complex molecular structures compared to small molecule, synthetic drugs and often provide highly specific biological activities likely derived from their rigidity and high number of chiral centers. Botanicals as a mixture can represent a library of natural product molecular structures some of which may possess bioactivity. This source of chemical information may be useful in efforts to approach new potential therapeutic targets or alternatively, assess potential risk from toxicity. Therefore, understanding the chemical composition of botanical mixtures, is a crucial step in discerning the relationship between molecular structure and biological activity or mode of action of a medicinal compound(s), especially in cases where novel chemical entities have been identified. A number of plant-derived preparations native to the Andean and Amazonian regions of South America have a long historical record of medicinal use in ethnotraditional practices, and continue to be in used in modern times in the form of botanical preparations. There are three plant preparations known as, Uncaria tomentosa (Cat's claw), Lepidium meyenii (Maca), and Croton lechleri (Dragon's blood) which have each been discovered from the empirical knowledge of local aborigines populations, and have since been scientifically investigated for their chemical composition and biological effects potentially applicable to therapeutic uses as, anti-viral, anti-inflammatory, anti-bacterial, cicatrizant, and anti-tumor agents. Moreover, some limited toxicity testing has also been reported with these mixtures and will be summarized. Against this background an evidence-based presentation will be given regarding the known chemical constituents and biological properties that have been reported for these plant-derived natural products.