Scutellaria brevibracteata subsp. subvelutina (Rech.f.) Greuter & Burdet: morphological and phytochemical characterization

A micromorphological and phytochemical survey was performed on Scutellaria brevibracteata subsp. subvelutina cultivated in Italy. The indumentum of the vegetative and reproductive organs was investigated: peltate, short-, medium- and long-stalked capitates were described. Histochemistry evidenced similar results for peltates and long-stalked capitates, differences for short and medium capitates. For the first time, this work reported the characterization of volatile organic compounds from leaves and flowers, along with the first analysis of the essential oil obtained from the aerial parts of Italian samples. The floral profile resulted more complex than the foliar one, due to the higher number of the total compounds (40 vs 27) and of the exclusive constituents (24 vs 11). 16 common compounds were detected, with beta-caryophyllene as the most abundant. The essential oil was characterized by 23 compounds, with beta-caryophyllene dominating. The peltates, the medium and the long-stalked capitates resulted the producers of the investigated compounds.