N-alkylamides of Spilanthes (syn: Acmella): Structure, Purification, Characterization, Biological Activities and Applications – A review

ABSTRACT Several species of Spilanthes, commonly known as the ‘toothache’ plants, are widely used by different communities as food ingredient in their traditional cuisines. Different parts of these plants are also used as medicine to treat diseases such as oral ulcers, stomatitis and toothache. The N-alkylamides (NAAs) present in Spilanthes species have been attributed to the biological properties such as anti-inflammatory, antimicrobial, aphrodisiac, antioxidant, insecticidal, larvicidal and astringent effects exhibited by this crop. Presence of NAA further allows usage of these plants as functional foods and cosmetics. Though interest in NAAs is enormous there is lack of studies with respect to the source material, mode of their action and user safety of NAA containing products. Therefore, a systematic survey of literature was done to present food and medicinal uses of Spilanthes plants, information on their NAAs, their distribution, biosynthesis, pharmacology, commercial potential and research lacunae. The review also attempts to caution the misnomer on the source material used for preparation of drugs from Spilanthes with a brief discussion on the plant's nomenclature and taxonomy.