Catnip (<i>Nepeta cataria</i> L.) Essential Oil: Analysis of Chemical Constituents, Bacteriostatic and Fungistatic Properties

Abstract

ABSTRACT The composition of the essential oil of flowering catnip (Nepeta cataria L., Lamiaceae) was analyzed by means of GC/MS. Besides the already known nepetalactones 4aα, 7α, 7aα-nepetalactone; 3,4β-dihydro-4aα, 7α, 7aα-nepetalactone; 4aα, 7α, 7aβ-nepetalactone and β-caryophyllene, five new constituents were identified: dimethyl-3,7 oxa-1 bicyclo [3,3,0] oct-2-ene, piperitone, thymol methyl ether, hexenyl benzoate and humulene oxide. The essential oil of two samples of the plant, collected at two different stages of development, was compared as to their nepetalactone content. The oil samples and a hexane extract were subjected to microbiological tests (five bacteria and seven fungi) and compared to natural compounds known for their antimicrobiological activities.