Composição química, atividade antimicrobiana e antioxidante do óleo essencial e extratos vegetais de Psidium cattleianum Sabine

Abstract

The constant search for natural antimicrobial products in substitution of synthetics, has increased in recent decades, mainly due to the indiscriminate use of conventional synthetic antimicrobials, resulting in the selection of resistant micro-organisms. In addition, there is a requirement of a share of consumers who demand products that do not harm the environment. Therewith, biodegradable disinfectants, plant extracts and essential oils are highlighted in studies that aim to control pathogens. Therefore, the objective of this study was to evaluate the antimicrobial activity of commercial disinfectants (emphasizing biodegradable), but also evaluate plant extracts and essential oil of Psidium cattleianum regarding potential antimicrobial, antioxidant and phytochemical characterization of them. To do so, disinfectants against strains of Salmonella, isolated from poultry environment, were tested, while plant extracts and essential oil using the broth microdilution methodology against standard strains. Regarding disinfectants, organic acid, peracetic acid, glutaraldehyde and quaternary ammonium were the most effective against Salmonella serotypes in the absence of organic matter, while the organic acids showed the best performance in the presence of organic matter. As to the phytochemical study of P. cattleianum, flavonoids, terpenoids and tannins in aqueous and ethanolic were found in the aqueous plant extract, while the essential oil presented as the major compounds α-copaene, eucalyptol, δ-cadinene and α-selinene respectively. Regarding antimicrobial activity, microorganisms have proved susceptible when evaluated against aqueous and ethanolic plant extracts, also to the essential oil (although this on higher concentration), demonstrating its antimicrobial potential of P. cattleianum. For antioxidant activity, the ethanolic and aqueous extracts had significant values comparable to synthetic antioxidants, while the essential oil showed no antioxidant activity