Chemical Composition and Allelopathyc Activity of Essential Oil of Lippia sidoides Cham

Abstract

The allelopathy is a process for which products of the secondary metabolism, as terpenes phenolic, of a certain vegetal intervene significantly, generally of antagonistic form, in the development of other species of plants. The objective of this work was to chemically characterize the essential oil of Lippia sidoides Cham. growing in the Cariri cearense region, Brazil, and evaluate the allelopathyc effect of this oil on the germination of lettuce (Lactuca sativa L.), arugula (Eruca sativa Mill.), and cauliflower (Brassica oleracea L.), in pre-plantation application. The monoterpene thymol (84.90%) has been identified as the principal constituent in the essential oil. The experiment was done in randomized complete block, in 4 × 3 factorial; being used four essential oil combinations applied in three different species in pre-plantation applications. Emergence velocity index (EVI), germination percentage and mean time to germination (MTG), had been analyzed through daily counting carried out until the 14 th day after sowing. Through qualitative analysis performed by gas chromatography coupled with mass spectrometry (GC/MS) were identified seven chemical constituents representing 97.82% of essential oil of L. sidoides, being that the constituent present in greater concentration in oil was the thymol (84.90%). Could be verified the occurrence of the negative allelopathyc effect of lettuce crop, because its present low EVI and greater MTG, for the other vegetable species there were no allelopathic effect.

Factors Affecting the Retention Efficiency and Physicochemical Properties of Spray Dried Lipid Nanoparticles Loaded with Lippia sidoides Essential Oil

“…Lippia sidoides, belonging to the genus Lippia [37,38], is a typical herb species of Northeast Brazil widespread used in traditional medicine; it is known in Brazil as "alecrim-pimenta" (pepper-rosemary). The main bioactive compounds in the EO of Lippia sidoides are monoterpenes, like thymol, p-cymene, myrcene, and the sesquiterpene, as caryophyllene [39][40][41]. These compounds are responsible for the biological properties of this EO, i.e., antimicrobial, antinociceptive, anti-inflammatory, and antioxidant activities [42][43][44].…”

The Effect of Pre-Harvest Treatments with Tanacetum vulgare L. and Satureja montana L. Essential Oils (EOs) on the Yield and Chemical Composition of Aronia melanocarpa (Michx.) Elliot Fruit

“…The latter authors found that this essential oil could be applied as a natural herbicide, being least harmful to all the tested species. Similarly, Lippia sidoides EO, also with thymol as its main component, exhibited negative effects on L. sativa [79]. It should be noted that, in the study of Wogiatzi et al [78], oregano EO (known for its high thymol content), when applied at high concentrations, caused significant damage to tomato plants, and the intensity of this phytotoxicity declined with decreasing oil levels.…”

Ciências Agrárias: limites e potencialidades em pesquisa - Volume 2

“…A alelopatia é uma interferência direta que as plantas podem exercer uma sobre as outras, através da produção de compostos químicos (aleloquímicos) que podem ser liberados no ambiente de quatro formas: exsudação de substâncias provenientes de raízes vivas; pela volatilização; lixiviação de substâncias de folhas, cascas, frutas, sementes; e decomposição do material vegetal depositado no solo (GREGORY, 2006). Tais substâncias podem estar em concentrações maiores na solução do solo do que nos tecidos radiculares (MARCO et al, 2012).…”