Composition and antimicrobial activity of the essential oil of Clinopodium ascendens (Jordan) Sampaio from Madeira

Clinopodium ascendens (Jordan) Sampaio [synonyms = Calamintha ascendens Jordan = C. officinalis Moench ssp. ascendens (Jord.) Mateo = C. sylvatica Bromf. ssp. ascendens (Jord.) P.W. Ball] is a small herbaceous plant with a very strong and distinctive mint aroma. The plant is known for its medical uses in folk medicine and as a spice in Italian kitchens. In Madeira Island, Clinopodium ascendens , known locally as ‘neveda’, grows wild along the shady paths of the Laurissilva forest. The local population uses the leaves of calamint as a mouth freshener and to alleviate headache and toothache. The essential oil obtained by hydrodistillation of the aerial parts of C. ascendens growing wild in Madeira was analysed by a combination of CC, GC, GC–MS, 1 H‐ and 13 C‐NMR. The oil was dominated by C 3 oxygenated p ‐menthane derivatives: cis ‐isopulegone (75.2%), pulegone (6.9%), neoiso ‐isopulegol (6.0%) and trans ‐isopulegone (4.5%). The whole essential oil was tested against a variety of bacteria, both Gram‐positive and Gram‐negative, and two fungi; it exhibited remarkable activity against Escherichia coli and was active against Agrobacterium tumefasciens and Staphylococcus aureus and the phytopathogenic fungus Botrytis cinerea . It was ineffective against Streptococcus faecium , Streptococcus mutans and Candida albicans. Copyright © 2006 John Wiley & Sons, Ltd.