Chemical Composition and Allelopathic Activity of the Essential Oil from <i>Callistemon viminalis</i> (Myrtaceae) Blossoms on Lettuce (<i>Lactuca sativa</i> L.) Seedlings

Abstract

The extraction of essential oils was performed by using the technique of hydrodistillation modified Clevenger apparatus, identification and quantification of the constituents was achieved by Gas Chromatography coupled to Mass Spectrometry, and Gas Chromatography equipped with a flame ionization detector. Assessment of allelopathic activity was evaluated with the use of the method that assesses the direct contact of essential oils on germination and vigor of lettuce seeds. The major constituents that characterize the essential oil from the flowers of Callistemon viminalis were 1, 8-cineole, α-pinene and limonene at concentrations of 66.9%, 16.0% and 10.0%, respectively. The essential oil presented allelopathic activity at intensities that varied proportionately to the concentration of the essential oil, with a reduction in the percentage of germination and the germination speed index (GSI) of lettuce seeds and in the dry mass and length of shoots and roots of lettuce seedlings.

Essential Oils from the Leaves and Flowers of <i>Callistemon viminalis</i>: Chemical Characterization and Evaluation of the Insecticide and Antifungal Activities

“…In Brazil, Silva et al [17] studied the essential oil from C. viminalis and obtained a yield of 0.3%. However, the essential oil content found in flowers was lower than that reported by Pires et al [18], who observed a content of 0.30% of essential oil in fresh flowers, and by Oliveira et al [7], who reported a yield of 0.24% on a moisture-free basis. According to Gobbo-Neto and Lopes [19], these variations can be attributed to differences in seasonality, temperature, and soil type, among others.…”

“…It is found in different localities, except in environments with a cold and dry climate [6]. The essential oil from this species can be found in both the flowers and the leaves, and there are studies that demonstrate antibacterial, allelopathic, and antioxidant activities for the essential oil from the leaves [7] [8]. However, there are no studies that report the biological potential of the essential oil from the flowers.…”

Chemical Composition and Insecticidal Activities of Essential Oils of Myrtaceae against Tribolium castaneum (Coleoptera: Tenebrionidae)

“…The oil contents of E. rudis and E. crebra were in accordance with previous reports [16,25,[38][39][40]. However, in E. microtheca, E. melanophloia, E. kitsoniana, E. tereticornis, M. quinquenervia, and M. bracteata, oil yields were found to be in lower amounts than the previous reports [38,[41][42][43][44]. No data was available to compare oil yield of E. pruinosa in literature.…”

Chemical Characterization, Antibacterial and Antioxidant Activities of Essential Oils of <i>Mentha viridis</i> L. and <i>Mentha pulegium</i> L. (L)

“…Essential oils are composed of a number of compounds of different biosynthetic origins ranging from terpenoid hydrocarbons to sulfur compounds [1], and such compounds are naturally present in different concentrations [2]. The essential oils of the Mentha genus have a high commercial value, because they usually contain the monoterpene menthol in their constitutions, and menthol is widely used in pharmaceutical, cosmetic, personal care and food products [3].…”