title: Glandular trichomes and essential oil characteristics of in vitro propagated Micromeria pulegium (Rochel) Benth. (Lamiaceae).
abstract: In vitro conditions and benzyladenine influenced both content and composition of micropropagated Micromeria pulegium essential oils, with pulegone and menthone being the main essential oil components. The content and chemical composition of Micromeria pulegium (Rochel) Benth. essential oils were studied in native plant material at vegetative stage and in micropropagated plants, obtained from nodal segments cultured on solid MS medium supplemented with N(6)-benzyladenine (BA) or kinetin at different concentrations, alone or in combination with indole-3-acetic acid. Shoot proliferation was achieved in all treatments, but the highest biomass production was obtained after treatment with 10 μM BA. Phytochemical analysis identified up to 21 compounds in the essential oils of wild-growing and in vitro cultivated plants, both showing very high percentages of total monoterpenoids dominated by oxygenated monoterpenes of the menthane type. Pulegone and menthone were the main essential oil components detected in both wild-growing plants (60.07 and 26.85 %, respectively) and micropropagated plants grown on either plant growth regulator-free medium (44.57 and 29.14 %, respectively) or BA-supplemented medium (50.77 and 14.45 %, respectively). The percentage of total sesquiterpenoids increased in vitro, particularly owing to sesquiterpene hydrocarbons that were not found in wild-growing plants. Differences in both content and the composition of the essential oils obtained from different samples indicated that in vitro culture conditions and plant growth regulators significantly influence the essential oils properties. In addition, the morphology and structure of M. pulegium glandular trichomes in relation to the secretory process were characterized for the first time using SEM and light microscopy, and their secretion was histochemically analyzed.
authors.affiliation: Department of Biology and Ecology, Faculty of Sciences and Mathematics, University of Niš, Višegradska 33, 18000, Niš, Serbia.
authors.forename: Dragana
authors.initials: D
authors.lastname: Stojičić
authors.affiliation: Department of Biology and Ecology, Faculty of Sciences and Mathematics, University of Niš, Višegradska 33, 18000, Niš, Serbia.
authors.forename: Svetlana
authors.initials: S
authors.lastname: Tošić
authors.affiliation: Department of Botany, Faculty of Pharmacy, University of Belgrade, Vojvode Stepe 450, 11000, Belgrade, Serbia.
authors.forename: Violeta
authors.initials: V
authors.lastname: Slavkovska
authors.affiliation: Department of Biology and Ecology, Faculty of Sciences and Mathematics, University of Niš, Višegradska 33, 18000, Niš, Serbia.
authors.forename: Bojan
authors.initials: B
authors.lastname: Zlatković
authors.affiliation: Institute for Biological Research "Siniša Stanković", University of Belgrade, Bulevar despota Stefana 142, 11060, Belgrade, Serbia.
authors.forename: Snežana
authors.initials: S
authors.lastname: Budimir
authors.affiliation: Institute of Botany and Botanical Garden "Jevremovac", Faculty of Biology, University of Belgrade, Takovska 43, 11000, Belgrade, Serbia.
authors.forename: Dušica
authors.initials: D
authors.lastname: Janošević
authors.affiliation: Institute for Biological Research "Siniša Stanković", University of Belgrade, Bulevar despota Stefana 142, 11060, Belgrade, Serbia. branka@ibiss.bg.ac.rs.
authors.forename: Branka
authors.initials: B
authors.lastname: Uzelac
mesh_terms: D000225:Adenine / Q000031:analogs & derivatives / Q000494:pharmacology; D046508:Culture Techniques; D000081005:Cyclohexane Monoterpenes; D007701:Kinetin / Q000494:pharmacology; D019686:Lamiaceae / Q000737:chemistry* / Q000254:growth & development / Q000648:ultrastructure; D008610:Menthol / Q000302:isolation & purification / Q000378:metabolism; D008855:Microscopy, Electron, Scanning; D039821:Monoterpenes / Q000302:isolation & purification / Q000378:metabolism; D009822:Oils, Volatile / Q000737:chemistry* / Q000302:isolation & purification; D064201:Trichomes / Q000378:metabolism* / Q000648:ultrastructure
chemical_list: D000081005:Cyclohexane Monoterpenes; D039821:Monoterpenes; D009822:Oils, Volatile; D008610:Menthol; C039648:pulegone; C019466:menthone; D000225:Adenine; D007701:Kinetin
keywords: Axillary bud induction; Capitate trichomes; Histochemistry; Micropropagation; Peltate trichomes; Phytochemical analysis