371 0009-3130/13/4902-0371  2013 Springer Science+Business Media New York Chemistry of Natural Compounds, Vol. 49, No. 2, May, 2013 [Russian original No. 2, March–April, 2013] PHYTOCHEMICAL COMPOSITION OF THE ESSENTIAL OIL OF Prunella grandiflora I. Jerkovic, 1* Z. Marijanovic, 2 K. Hazler Pilepic, 3 UDC 547.913 and Z. Males 3 Prunella grandiflora (L.) Scholler, Lamiaceae, is a thermophilous, European-West Asian perennial herb [1]. Like other members of the genus Prunella, which is currently of great interest due to new and important therapeutic applications [2], it has been used traditionally as an external remedy for the treatment of wounds [3]. Although the majority of Lamiaceae species are aromatic, as far as we know there is no report on the essential oil composition of P. grandiflora. P. grandiflora essential oil was isolated by hydrodistillation and analyzed by GC and MS. The phytochemical composition of the oil is presented in Table 1. A total of 40 volatiles was identified, and two nonterpene compounds dominated in the oil: (E,E)-hepta-2,4-dienal, (17.8%) and phenylacetaldehyde (13.2%). Aliphatic aldehydes and alcohols were abundant in the oil: (E,E)-hepta-2,4-dienal, followed by (E)-2-hexenal, (Z)-3-hexen-1-ol, (E,E)-2,4-hexadienal, and 1-octen-3-ol. Their biosynthetic origin could be connected to the corresponding fatty acid degradation, but only smaller percentages of tetradecanoic acid and hexadecanoic acid were present in the oil of P. gradiflora (Table 1). (E,E)-2,4-Heptadienal and 1-octen-3-ol were also identified among the major constituents of Prasium majus L. essential oil [4]. In addition, naturally occurring (E,E)-2,4-heptadienal has been found among the main volatiles in the body of the swallowtail butterfly Papilio machaon (Lepidoptera: Papilionidae) [5]. Phenylacetaldehyde is not often present in typical essential oils in high percentages and was previously identified as the major constituent of the essential oil of Suregada zanzibariensis leaves [6]. Other abundant chemical groups of identified volatile organic compounds consist of oxygenated monoterpenes that contained ubiquitous essential oil constituents such as linalool (7.0%), trans-pinocarveol (6.5%), myrtenol (3.8%), terpinen-4-ol (3.2%), menthol (3%), and others (Table 1). Beside phenylacetaldehyde, two isomers, thymol (2.8%) and carvacrol (3.5%), were found among the phenylpropane derivatives. Due to the presence of oxygenated monoterpenes along with thymol and carvacrol that exhibit well-known biological activity (such as antioxidant or antimicrobial) [7, 8], the essential oil can contribute to the previously observed therapeutic application of the plant [2, 3]. Only few sesquiterpenes were found: -copaene, -caryophyllene, spathulenol, and caryophyllene oxide. Unlike most aromatic plants, monoterpene hydrocarbons were hardly present (low percentages of -pinene, p-cymene, and (Z)--ocimene) among P. grandiflora L. volatile compounds. Comparison with constituents of the essential oil from three plants of Prunella (P. vulgaris L., P. asitica Nakai, and P. hispida Benth.) revealed major differences. Namely, the essential oil from their fruiting spikes contained 14–17 compounds [9]. Among them, hexadecanoic acid was the major constituent. Plant Material and Isolation Procedure. The aerial parts of P. grandiflora in the flowering period were collected randomly from a large number of individuals at a wide area of Ucka Mountain (Croatia) in June, 2011. A voucher specimen is deposited in the Herbarium of the Department of Pharmaceutical Botany (FB 1351). Plant material (50 g) and water (250 mL) were placed in a Clevenger-type apparatus. The essential oil was isolated by hydrodistillation for 2 hours with pentane as solvent trap. The obtained essential oil in pentane was separated, dried over anhydrous sodium sulfate, and stored under argon in a sealed vial at 4C until GC-FID and GC-MS analysis. Identification of the Essential Oil Components. Analyses of isolated essential oil were performed using GC-FID and GC-MS. 1) Department of Organic Chemistry, Faculty of Chemistry and Technology, University of Split, N. Tesle 10/V, HR-21000 Split, Croatia, fax: 00385 21 329 461, e-mail: igor@ktf-split.hr; 2) “Marko Marulic” Polytechnic of Knin, P. Kresimira IV 30, HR-22300 Knin, Croatia; 3) Department of Pharmaceutical Botany, Faculty of Pharmacy and Biochemistry, University of Zagreb, Schrottova 39, HR-10000 Zagreb, Croatia. Published in Khimiya Prirodnykh Soedinenii, No. 2, March–April, 2013, pp. 314–315. Original article submitted January 15, 2012.