Volatile components and antifeedant activity of the essential oil from Scutellaria hastifolia L.

The genus Scutellaria comprises about 300 species of herbs or subshrubs and rarely shrubs, some of which with ecological properties such as anti-feedant and anti-fungal [1]. These properties are often due to the presence of essential oils [2]. Scutellaria hastifolia L. (leafy skullcap) is a perennial gramineous plant with the running rhizome; it is a rare species in Lithuania, where is called Ieçialape kalpoke and grows in meadows (often in the water-meadows) and riversides [3]. No report on the essential oil of this species has been found in the literature so far, therefore in this communication we describe the volatile compounds of S. hastifolia collected in Lithuania on June 2007 and its activity against the feeding and egg laying behaviour of Spodoptera littoralis, a polyphagous insect attacking a number of plant species. The oil was isolated by hydrodistillation [4]. The GC and GC/MS analyses evidenced the presence of 50 compounds, accounting for 92.1% of the oil that consisted mainly of terpenoids, particularly sesquiterpenes (61.5%), among which sesquiterpenes hydrocarbons (44.9%) prevailed over oxygen containing sesquiterpenes (16.6%). The most representative compounds were caryophyllene (12.9%), germacrene D (7.7%), caryophyllene oxide (6.9%), hexadecanoic acid (6.3%) and hexahydrofarnesylacetone (5.6%). Binary choice bioassays were undertaken to investigate if the essential oil could modulate the feeding behaviour of final stadium larvae of S. littoralis.

References: [1] Bruno, M. et al. (2002) Biochem. Syst. Ecol. 30:793–799.

[2] Rosselli, S. et al. (2007) Biochem. Syst. Ecol. 39:797–800.

[3] Galinis, V. (1976) Scutellaria L. – In: Natkevičaitė-Ivanauskienė, M. (ed): Flora of the Lithuanian SSR, No 5. Vilnius.

[4] European Pharmacopoeia 5th ed. (2004). Council of Europe, 217.