Botany, traditional uses, phytochemistry and pharmacology of Waltheria indica L. (syn. Waltheria americana): a review

Abstract

Ethnopharmacological relevance: Waltheria indica L. (syn. Waltheria americana) is commonly used in traditional medicine in Africa, South America and Hawaii, mainly against pain, inflammation, conditions of inflammation, diarrhea, dysentery, conjunctivitis, wounds, abscess, epilepsy, convulsions, anemia, erectile dysfunctions, bladder ailments and asthma. Aim of the review to provide an up-to-date overview of the botany, phytochemistry, traditional uses, pharmacological activities and toxicity data of Waltheria indica. Additionally, studies providing an evidence for local and traditional uses of Waltheria indica are discussed. Further phytochemical and pharmacological potential of this species are suggested for future investigations.

Materials and methods: The information was collected from scientific journals, books, theses and reports via academic libraries and electronic search. These sources include Pubmed, Web of Science, Portal de Portales-Latindex, Science Research.com and Google scholar. These studies about the medical botanical, traditional uses, chemical, pharmacological and toxicological data on Waltheria indica were published in English, Portuguese, Spanish, German and French.

Results: Crude extracts and isolated compounds from Waltheria indica were investigated and showed analgesic, anti-inflammatory, antibacterial, antifungal, antimalarial, anti-anemic, anti-oxidant, sedative and anticonvulsant activities. The phytochemical investigations showed the presence of cyclopeptid alkaloids, flavonoids (e.g., (-)-epicatechin, quercetin, kaempferol, kaempferol-3-O-β-d-(6″-E-p-coumaryl)-glucopyranoside), tannins, sterols, terpenes, saponins, anthraquinones. Studies of acute toxicity in animal indicated that Waltheria indica can be toxic.

Conclusion: Waltheria indica possess therapeutic potential in the treatment of inflammation, malaria, infectious diseases (e.g., lungs infection due to Klebsiella pneumoniae, diarrhea due to Candida albicans or Escherichia coli) and prevention of oxidative stress. Further studies are necessary to explore pure compounds responsible for the pharmacological effects and the mechanisms of action. Further investigations are also needed to provide an evidence base for traditional uses of this species against pain, anemia, convulsions and epilepsy. In addition, there is a pressing need to investigate the other traditional uses such as dysentery, syphilis, erectile dysfunctions and asthma.