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This study aimed to evaluate the effects of essential oils from the fruits of Citrus sinensis and Xylopia aromatica , included in broiler feed, on blood parameters, the biometrics of digestive organs, bone analyses, and the biochemical profiles of the viscera, as well as the histomorphometry of the small intestine. In this study, 180 one-day-old male chicks of the Cobb 500 strain were fed a corn and soybean meal over three treatments and six replications, and the experimental design was completely randomized. The data were subjected to an analysis of variance and a Tukey test at a 5% significance level. The effect of the experimental diets on performance, blood parameters, biometrics of the digestive organs, bone analysis, and biochemical profiles of the viscera, as well as the histomorphometry of the small intestine, were evaluated. The compounds identified in the essential oil of X. aromatica were sylvestrene, α-pinene, and β-pinene, while in C. sinensis they were limonene and myrcene. The essential oils of C. sinensis and X. aromatica had no significant effect on performance at 14 days. The effects of the presence of the essential oils of C. sinensis and X. aromatica on the response were beneficial: there were reductions in liver lipids, cholesterol, and triglycerides, and in the depths of the crypts in the jejunum of chickens. So, the essential oils from the fruits of C. sinensis and X. aromatica can be used in broiler chickens to improve the lipid profiles of birds without affecting their performance.

Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae) Middle-East Asia Minor 1 is a major pest of agricultural production systems. It is controlled by synthetic insecticides. Essential oils are promising eco-friendly alternatives. This study developed and characterized nanoparticles loaded with essential oils of Zanthoxylum riedelianum Engl. (Rutaceae) leaves and evaluated their potential for B. tabaci management. The essential oil exhibited an average yield of 0.02% (w w -1 ) and showed as major components γ-elemene (24.81%), phytol (18.16%), bicyclogermacrene (16.18%), cis-nerolidol (8.26%), and D-germacrene (6.52%). Characterization of the nanoparticles showed a pH between 4.5 and 6.7, a zeta potential of approximately - 25 mV, particle-size distribution ranging from 450 to 550 nm, and encapsulation efficiency close to 98%. The nanoencapsulation was an efficient process that provided photostability against photodegradation. Bioassays with crude and nanoencapsulated essential oils significantly reduced the number of nymphs and eggs of B. tabaci, with the best results observed at concentrations of 5 and 2% (v v -1 ). Our results demonstrated that essential oils from Z. riedelianum can be nanoformulated resulting in a stable product while maintaining their biological activity against B. tabaci Middle-East Asia Minor 1., (© 2022. Sociedade Entomológica do Brasil.)

This study aimed to evaluate the antibacterial and antibiotic-enhancing effects of the essential oil obtained from Ocimum gratissimum L. (OEOg) alone or in association with light-emitting diodes (LED) lights. The essential oil was obtained by hydrodistillation and its chemical composition analysed by gas chromatography coupled to mass spectrometry. The antibacterial and antibiotic-enhancing activities against multiresistant strains of Staphylococcus aureus and Escherichia coli were evaluated by the gaseous contact method. The analysis of the photoinductive effect on the antibacterial activity of the OEOg and antibiotics was assessed through exposure to different LED lights (red, blue and yellow). The phytochemical analysis identified five compounds, including eugenol, as the major constituent. The OEOg caused a significant inhibition of the halo, indicating a direct antibacterial effect. Exposure to the LED lights significantly enhanced the activity of the OEOg against E. coli. On the other hand, the action of the essential oil against S. aureus was enhanced by exposure to both blue and yellow lights. The effects of LED light exposure on the activity of conventional antibiotics varied significantly according to the drug and the bacterial strain. However, most combinations of LED lights and the OEOg presented synergistic effects against resistant bacterial strains, indicating enhanced antibacterial activity. Thus, these in vitro findings suggest that both OEOg and LED lights have promising antibacterial effects. Nevertheless, further research is required to evaluate in vivo the potential of these therapies for the treatment of infectious skin diseases.