The jalap roots: A herbal legacy from the neotropics to the world

The Convolvulaceae or morning glory family, with about 2000 species in the world's Tropics and subtropics, stands out among the plants used in traditional medicine. Medicinal plant complexes with important purgative properties have been developed in Mexico and Brazil from members of the genera Ipomoea and Operculina with storage roots. Popularly known as the jalap roots, their resin glycosides cause purgative and laxative activities that facilitate bowel movements.

This article reviews the importance of the Convolvulaceae family in herbal medicine with a holistic approach that includes a historical perspective, as well as descriptions of crude drugs, phytopharmaceuticals, and chemical constituents. It further considers the family's distribution and biological properties, such as documented purging and cytotoxic activities of the Mexican and Brazilian jalap roots. The main aim of this review is to afford insights into the use and management of medicinal jalap roots for their potential development as herbal medicines.

A search for available information on the genera and species that constitute the jalap roots was conducted using scientific databases, including PubMed, Google Scholar, ScienceDirect, and the International Plant Names Index. Also, numerous historical European herbals, botanical books, and pharmacopeias were reviewed using the Biodiversity Heritage Library and Internet Archive.

The review establishes that from the initial introduction of the medicinal jalap roots to Europe in the 16th century, various types of Neotropical purging roots were confused. The misunderstanding resulted from similar traditional uses of several species with common morphological features, organoleptic characteristics, and vernacular names. Subordinate species were also frequently used as substitutes for the signature or officinal crude drug. A compendium of contemporary uses of Mexican and Brazilian jalaps in herbal medicine is also presented.

Mexican and Brazilian jalap roots, still in use in traditional medicine, offer great potential as sources of biologically active principles. Research should prioritize the investigation on their chemical markers, toxicity, mechanisms of action, ecological requirements, and ecological networks. An integrated ethnopharmacological approach, which has not been adequately explored, would promote their proper management as novel phytopharmaceuticals.