Phytochemical analysis of Teucrium polium L

The phytochemical analysis of the ethanolic extract of a sample of Teucrium polium L. (Lamiaceae) represented by fresh stem and leaves, collected in Northern Iran on the rocky lands of the Alborz mountain at an altitude of about 2000 m a.s.l. in late May 2015, led to the isolation (CC and HPLC) and to the identification (NMR and MS), of seven compounds namely teucrasiatin (1), 20-O-acetyl-teucrasiatin (2), verbascoside (3), apigenin (4), luteolin (5), acacetin (6) and apigenin 7-O-β-glucoside (7). These compounds are all of high relevance: compound (2), even though already known by synthesis, was isolated here for the first time from a natural source together with compound (1) previously recognized only in T. asiaticum.. The presence of neo-clerodanes may explain why this plant is ultimately no longer used, except for Iran, for medical purposes given that they are deemed to exert, even in small amounts, high hepatotoxic effects often resulting into patients’ death. On the other side, the other recognized constituents, always found as mixtures and in high amounts in this accession, have already been reported for the species and the genus but altogether give a valuable phytochemical rationale of its ancient and historical uses as anti-inflammatory, anti-pyretic, anti-diabetic, anti-rheumatic, digestive and abdominal pain killer properties, since they are well known to be responsible of these activities. In conclusion, several health promoting agents besides potentially toxic compounds were evidenced during our study on T. polium, revealing so a double nature of this medicinal plant. It’s all up to determine which of them must be taken in more account and for this reason it seems to be very necessary deeper phytochemical studies on this and related species.