Chemical composition, phytotoxicity and cytogenotoxicity of essential oil from leaves of Psidium guajava L. cultivars

Abstract

Natural products with biological activity, such as essential oils, can be used in the search for and development of ecological herbicides as an alternative to reduce the damage caused by synthetic herbicides. This work to aimed to determine the chemical composition and phytotoxic properties of the essential oils, at concentrations of 3000, 1500, 750, 375 and 187.5 µg/mL, of four cultivars of Psidium guajava (guava) evaluated on germination and root growth of plant models Lactuca sativa and Sorghum bicolor, as well as in the L. sativa cell cycle. Exposure to essential oils reduced germination and root growth in bioassays, especially at the highest concentration (3000 µg/mL). The essential oils interfered in the normal dynamics of the cell cycle of L. sativa at most concentrations, causing a decrease in the mitotic index and increasing of chromosomal alterations, evidencing aneugenic and clastogenic action. The biological activity of the oils was associated with the presence of sesquiterpenes and monoterpenes found here, such as caryophyllene oxide, (E) -caryophyllene, and limonene. Thus, the essential oils of cultivars of guava demonstrated the promising potential for use as natural herbicides.

A review of essential oils and their properties in the genus Campomanesia (Myrtaceae) from the Brazilian Cerrado

“…The best known and most common terpenes are monoterpenes (with 10 carbon atoms), comprising limonene, α-pinene and β-pinene, and sesquiterpenes (15 carbon atoms), including bicyclogermacrene, spathulenol and thujopsene (Simões & Spitzer, 2000). Biological assays provide evidence that these chemicals have biological activities, such as against cancer (Alves et al, 2020;Garcia et al, 2020;Vasconcelos et al, 2021) and cardiovascular disease (Menezes et al, 2010), along with anti-hyperalgesic and anti-inflammatory activities (Chi et al, 2013;D'Alessio et al, 2013;Piccinelli et al, 2015). Due to these health-related benefits, the global market in EOs is around US$15 billion, and the price of a kilogram of EO exported from Brazil was US$5.90 in 2021(Bueno et al, 2021.…”