Plants have formed the basis of traditional medicine systems that have been in existence for thousands of years, and plant-based traditional medicines continue to play an essential role in health care (Gurib-Fakim 2006). Although modern medicine is available in most countries, traditional herbal medicines have maintained popularity for historical and cultural reasons. In addition, they have been used as alternative or complementary therapies, including medicinal herbs (WHO 1999). In the pharmaceutical industry, natural products isolated from medicinal plants have served as models for the creation of synthetic analogues (Borowitzka 1995). Natural products or drugs derived from them represent more than 50% of all the drugs in clinical use, such as many of those used for the treatment of cancer (Alonso, Castro, and Martinez 2005; Gurib-Fakim 2006).