Natural indigo, as one of the oldest dyes, is also a pivotal dye utilized in cotton fabrics today. A diversity of plants rich in indigo compounds belong to traditional Chinese herbal medicines. Indigo compounds have a variety of biological and pharmacological activities, including anticonvulsant, antibacterial, antifungal, antiviral and anticancer activities. A substantial progress in indigo biosynthesis has been made lately. This paper summarizes the value of indigo from the aspects of cultural history, biosynthetic pathways and the medicinal activities of its related derivatives involved in the pathways. In addition, the latest research advancements in indigo biosynthetic pathways is demonstrated in this paper, which would lay the theoretical foundation for the exploration and utilization of natural indigo.
Keywords: biosynthetic pathway; indigo; medicinal value; research progress.