Comparative study on the essential oils of Myosotis arvensis and Myosotis palustris herbs (Boraginaceae)

Paulina Znajdek-Awiz_ en 0 1 Wiesawa Bylka 0 1 Dorota Gawenda-Kempczyn ska 0 1 Iwona Paszek 0 1 M. palustris 0 1 0 D. Gawenda-Kempczynska I. Paszek Department of Biology and Pharmaceutical Botany, Nicolaus Copernicus University , Collegium Medicum in Bydgoszcz, 9 Marii Curie-Sklodowskiej, 85-094 Bydgoszcz, Poland 1 P. Znajdek-Awiz_en (&) W. Bylka Department of Pharmacognosy, Poznan University of Medical Sciences , 4 Swiecickiego, 60-781 Poznan, Poland The essential oils were obtained from Myosotis arvensis L. and M. palustris L. by hydrodistillation and subsequently analyzed by GC-MS. Fifteen components in M. arvensis and twenty-one in M. palustris representing, respectively, 89.63 and 93.19 % of the total oils were identified on the basis of their retention time, mass spectra characteristics and semi-quantitative data were obtained from relative peak area percentages. The 3-methyl-benzaldehyde was found to be the major constituent of both tested oils (42.76 % in M. arvensis and 45.80 % in M. palustris). Additionally, methyl salicylate was a characteristic compound for M. arvensis and a-bisabolol oxide B for M. palustris. Communicated by M. H. Walter. - Genus Myosotis belongs to the Boraginaceae family and includes about 100 species occurring mainly in western Eurasia and New Zealand. Both species differ in morphology and occupy various habitats. M. palustris is covered with straight hairs, decumbent to upright angular stem, rhizome and crown diameter of 58 mm. M. arvensis is also covered with hairs, crown with a diameter of 45 mm and petioles which are 23 times longer than calyx during fruiting. Hairs on the floral cup are hook shaped (Rutkowski 1998). M. palustris prefers places with moderate light (light indicator according to EllenbergL7) and soil with high humidity (moisture indicatorF8). It occurs in wet meadows, at the edge of waters, wetlands. M. arvensis prefers a slightly smaller amount of light than M. palustris. It occurs in wet meadows, at the edge of waters, wetlands (light indicatorL6) on fresh and dry soils (moisture indicatorF5) like fields, fallows, roadsides, grasslands and forest edges (Jager 2011). According to the literature, the species of genus Myosotis contain alkaloids, saponins and higher fatty acids (Shinkarenko 2008). However, detailed reports on the chemical constituents of M. arvensis and M. palustris are scarce so far. Folk medicine recommends M. arvensis in the treatment of malignant tumor of the oral cavity and sex organs and in tuberculosis (Shinkarenko and Vasilev 2008). Study conducted in mice showed that aqueous extracts of the aerial part of the M. arvensis exert anxiolytic and antidepressant activity (Polomeyeva et al. 2011). It was also proved that oil extracts of both herbs inhibit the development of bacteria microorganisms, e. g., Shigella sonnei and Candida albicans. Moreover, the extracts of M. arvensis inhibit viability of Staphylococcus aureus and Streptococcus faecalis and the M. palustris extracts inhibit the growth of Pseudomonas aeruginosa (Shinkarenko 2008). It has already been shown that essential oils may, despite their small amounts, contribute to the therapeutic activities of the plants (Radulovic et al. 2006). Among the major biological activities of essential oils antibacterial, antifungal and anti-inflammatory properties are mentioned. The aim of this study was phytochemical investigation and comparison of the components of the M. arvensis and M. palustris volatile oils. To the best of our knowledge, there are no previous reports on the essential oil profile of species belonging to genus Myosotis (Boraginaceae). Materials and methods M. arvensis and M. palustris herbs were collected from the natural habitats in Central Poland (May and June 2012). Voucher specimens have been deposited in the Department of Pharmacognosy, Poznan University of Medical Sciences, Poznan. A 30 g samples of dried M. arvensis and M. palustris herbs were hydrodistillated in a Clevenger-type apparatus with 500 ml of distilled water for 3 h. Identification of essential oils composition (GCMS analysis) The analysis of chemical composition of essential oils was performed using Varian 4000 GCMS, electron energy of 70 eV and ion source temperature of 200 C. The instrument was equipped with VF-5 ms silica column (30 m 9 0.25 mm 9 0.39), df = 25 lm. Helium was the carrier gas at the flow rate of 1 mL/min and the split ratio 1:10. The oven temperature was programmed at 40 C (held for 2 min) then gradually increased to 280 C at the rate of 15 C/min. The detector temperatures were: 180 C for ion trap, 50 for manifold and 220 C for the transfer line. Identification of components was based on comparison of their retention time, as well as mass spectra with standards from the NIST mass spectra library and literature data (Adams 2007). Semi-quantitative data were obtained from relative peak area percentages. Results and discussion Hydrodistillation of the herbs of M. arvensis and (...truncated)