Secondary metabolites content of two Stachys species: S. germanica subsp. salviifolia (Ten.) Gams and S. annua subsp. annua (L.) L.

Stachys is an important and large genus belonging to the Lamiaceae family comprising 31 species in Italy out of 450 with characteristics not common and specific among themselves. In this work we report the contents of the polar fractions of Stachys germanica L. subsp. germanica and S. annua L. subsp. annua. The study of the ethanolic extract of the former allowed the isolation and identification of two flavonoids, isoscutellarein derivates, a phenyl-propanoid, stachysoside, a caffeoylquinic derivative, clorogenic acid and lastly one iridoid, harpagide. They all have been already evidenced in this genus and some are considered chemotaxonomic markers. On the other hand, the study of the latter led to the isolation and identification of two flavonoids, again isoscutellarein derivates. These last compounds containing allose have been often evidenced in several genera of the Lamiaceae family such as Sideritis and even Stachys itself, thus confirming their own chemotaxonomic proximity. Making a comparison between the two studied plants it can be noted that only a compound, one of the isoscutellarein derivates, was found in both species: in particular the observed composition of S. germanica resulted in accordance with those reported for several Stachys species, while S. annua showed only the presence of flavonoids, instead. Such fact might be a starting basis for a reconsideration of the systematic collocation of this species.