Lippia integrifolia (Griseb.) Hieron.

Abstract

Lippia integrifolia (Griseb.) Hieron. is a native aromatic shrub commonly known as "incayuyo" or "inca tea" widely used in traditional medicine in northern and central Argentina where infusions of leaves and flowers are used as digestive, emmenagogue, antitussive, carminative, and against dyspepsia, stomach ache, flu and indigestions. Its essential oil is a rich source of sesquiterpenoids based on unique or very rare skeletons such as integrifoliane, lippifoliane, asteriscane, africanane and 4,5-seco-africanane. The essential oil shows a remarkable chemical diversity with at least five clearly defined chemotypes. Two of the most frequently found chemotypes are noteworthy by their unique chemical constituents, one called ´trans-davanone chemotype´ that has such a ketone as the dominant component (>75%), and the other, called ´lippifolienone chemotype´, rich in oxygenated sesquiterpenoids with unique sesquiterpenic skeletons baptized as integrifoliane and lippifoliane accompanied by sesquiterpenoids based on the rare asteriscane, africanane and 4,5-seco-africanane skeletons. Aqueous and ethanol extracts of incayuyo showed antiadhesive properties against Helicobacter pylori. In addition, the secretion of IL-8 induced by Helicobacter pylori was significantly reduced by co-incubation of AGS cells with incayuyo extract. Infusions and decoctions of incayuyo displayed strong antioxidant, choleretic and antispasmodic effects, stimulated phagocytosis rate of macrophages and inhibited the LPS-induced NO-secretion. In addition, a significant reduction of contractions induced by acetylcholine, CaCl2 and KCl was observed in isolated rat jejunum. The bioactive components of the incayuyo are flavonoid glycosides, (poly) phenolic compounds, phenylethanoid glycosides (acteoside, isoacteoside) and sesquiterpenoids. All experimental data support the use of incayuyo in traditional medicine. Comparative studies on the pharmacological efficacy of the different essential oil chemotypes are necessary, particularly in relation to the qualitative and quantitative content of non-volatile bioactive metabolites to define quality parameters.