Stachys italica Mill.: synecology, functional compounds and potential use of an Italian endemic taxon.

Main conclusion: The metabolomic of the Italian endemic species Stachys italica was investigated and potential positive metabolites for human's health were detected, quantified and discussed in relation to its synecology. Stachys italica is a species endemic to central-southern Italy, traditionally used for human consumption. The present research reports the results of a phytosociological study of this species in two southern regions of Italy (Apulia and Calabria). The collected plant material was used to make two types of extracts: hot water infusion to evaluate the use of this plant as tea and hydroalcoholic extraction to evaluate the use of it in herbal liqueur preparation. The extracts obtained by the hot water infusion had a values of total polyphenols and antioxidant capacity similar to values found in black tea. The analysis of non-volatiles compounds revealed the presence of biologically active substances like lavandulifolioside, verbascoside, and methoxyflavones. The analysis of volatiles fraction of metabolites demonstrated fifty-three volatiles compounds in the plant aerial part, 19 of which belonging to monoterpenoids, and 17 to the class of sesquiterpenoids. Among them, α-pinene, β-pinene, cis-ocimene, limonene and t-caryophyllene, were the most abundant compounds. The results were compared with already published results and referred to other similar species (such as Sideritis syriaca) which represent herbal mixtures usually collected and used as "mountain tea" in the Balkans and Eastern European countries.