Navegando por Palavras-chave "N. Megapotamica"

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    Perfil químico dos óleos voláteis de indivíduos jovens de Nectandra megapotamica (Spreng.) Mez (Lauraceae) sob déficit hídrico 2018
    (Universidade Federal de São Paulo, 2018-11-23) Santos, Valdilene Maria dos [UNIFESP]; Lago, João Henrique Ghilardi [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)
    In this work the chemical composition of the volatile oils of the leaves of young individuals of Nectandra megapotamica under normal conditions of cultivation and under water deficit was carried out under three conditions: plants irrigated every two days (group I), every seven (group II) and every 15 days (group III). The study was conducted during 60 days in greenhouse, with biweekly collections, being repeated in three distinct periods, covering the four seasons of 2017 (summer/autumm, autumn/winter and spring). The qualitative and quantitative analysis of the constituents present in the volatile oils was performed using gas chromatography with flame ionization detector (GC/FID) and gas chromatography coupled to mass spectrometry (GC/ MS). 25 Compounds were identified, four monoterpenes (Δ 3 -carene, o-cymene, d-limonene and bornila acetate), eighteen sesquiterpenes (δ-elemene, α-copaene, βelemene, Z-α-bergamotene, β-caryophyllene, α-humulene, alloaromadendrene , germacrene D, δ-selinene, β-bisabolene, α-bisabolene, α-elemol, E-nerolidol, espatulenol, globulol, rosifoliol, alismol and α-bisabolol), as well as two diterpenes (caurene and E-phytol) and one phenylpropanoid (E-asarone). The summer/autumm and fall-winter experiments responded more strongly to the water deficits imposed, especially autumn-winter, in which the lowest water potential (-1.0 MPa) was observed. The contents of the constituents of the volatile oils of N. megapotamica underwent quantitative/qualitative variation throughout the experiment, being the most intense observed for the summer/autumm and fall-winter. The reductions in the relative proportions of the constituents were more evident for the oxygenated sesquiterpenes, especially for the plants with greater water restriction (group III). In addition, a systematic study was carried out throughout the year 2017, covering the summer/fall, autumn/winter and spring seasons, where relative variations of the constituents present in N. megapotamica volatile oils were observed. water deficiency treatments imposed. In order to understand which constituents had similarities and / or differences among them as a result of the treatments, principal component analyzes (PCA) were performed. It was possible to establish some relationships such as, in the summer/autumm experiment the α-bisabolol oxygen sesquiterpene was related to samples with higher water availability, whereas germacrene D was more relevant in samples with low water availability. Physiological analyzes (water potential, relative water content and growth rate) were also carried out to verify if the plants were responding to the treatments. In view of the obtained results, it can be suggested that the controlled conditions can be an alternative to select substances with biological activity of interest and commercially aggregated value, thus allowing the choice of Keywords: PCA, GC-FID, GC-MS, Water deficit, N. megapotamica, volatile oils, chemical composition. a better period to obtain them.