title: Phytotoxicity and Cytotoxicity of Essential Oil from Leaves of Plectranthus amboinicus, Carvacrol, and Thymol in Plant Bioassays.
abstract: The essential oil of Plectranthus amboinicus and its chemotypes, carvacrol and thymol, were evaluated on the germination and root and aerial growth of Lactuca sativa and Sorghum bicolor and in acting on the cell cycle of meristematic root cells of L. sativa. The main component found in the oil by analysis in gas chromatography-mass spectrometry and gas chromatography flame ionization detection was carvacrol (88.61% in area). At a concentration of 0.120% (w v(-1)), the oil and its chemotypes retarded or inhibited the germination and decreased root and aerial growth in monocot and dicot species used in the bioassays. In addition, all substances caused changes in the cell cycle of the meristematic cells of L. sativa, with chromosomal alterations occurring from the 0.015% (w v(-1)) concentration. The essential oil of P. amboinicus, carvacrol, and thymol have potential for use as bioherbicides.
authors.forename: Patrícia Fontes
authors.initials: PF
authors.lastname: Pinheiro
authors.forename: Adilson Vidal
authors.initials: AV
authors.lastname: Costa
authors.forename: Thammyres de Assis
authors.initials: Tde A
authors.lastname: Alves
authors.forename: Iasmini Nicoli
authors.initials: IN
authors.lastname: Galter
authors.forename: Carlos Alexandre
authors.initials: CA
authors.lastname: Pinheiro
authors.affiliation: Department of Food, Nutrition School, Federal University of Ouro Preto , Morro do Cruzeiro, s/n, Bauxite District, 35400-000 Ouro Preto, Minas Gerais, Brazil.
authors.forename: Alexandre Fontes
authors.initials: AF
authors.lastname: Pereira
authors.forename: Carlos Magno Ramos
authors.initials: CM
authors.lastname: Oliveira
authors.forename: Milene Miranda Praça
authors.initials: MM
authors.lastname: Fontes
mesh_terms: D001681:Biological Assay; D000081007:Cymenes; D018545:Lactuca / Q000187:drug effects / Q000235:genetics / Q000254:growth & development; D013058:Mass Spectrometry; D039821:Monoterpenes / Q000737:chemistry / Q000633:toxicity*; D009822:Oils, Volatile / Q000737:chemistry / Q000633:toxicity*; D010936:Plant Extracts / Q000737:chemistry / Q000633:toxicity*; D018515:Plant Leaves / Q000737:chemistry; D031346:Plectranthus / Q000737:chemistry*; D012639:Seeds / Q000187:drug effects / Q000254:growth & development; D045868:Sorghum / Q000187:drug effects / Q000235:genetics / Q000254:growth & development; D013943:Thymol / Q000737:chemistry / Q000633:toxicity*
chemical_list: D000081007:Cymenes; D039821:Monoterpenes; D009822:Oils, Volatile; D010936:Plant Extracts; D013943:Thymol; C073316:carvacrol
keywords: allelopathy; mutagenicity; volatile constituents of P. amboinicus