Use of eugenol for anesthesia of lesser guitarfish Zapteryx brevirostris (Rhinobatidae) / Uso de eugenol para anestesia de raia-viola Zapteryx brevirostris (Rhinobatidae)

Abstract Anesthesia can be utilized as a non-lethal procedure to allow easy handling of teleosts and elasmobranchs in captivity or in the wild. For this, anesthetic protocols need to be established according to the species. The aim of this study was to determine the ideal concentration of eugenol for anesthesia of Zapteryx brevirostris. Four concentrations were tested: 21.25, 42.50, 85.00 and 170.00 mg L-1 (ratio of 1:5 with absolute ethanol). The perfect concentration of eugenol for this species was 85.0 mg L-1 , which enabled up to 300 seconds of work on the fish, without any response to handling.

Resumo A anestesia pode ser utilizada como um procedimento não letal que facilita o manejo de teleósteos e elasmobrânquios de cativeiro e de vida livre. Para isso, protocolos anestésicos devem ser estabelecidos de acordo com a espécie. O objetivo deste trabalho foi determinar a concentração ideal do eugenol para anestesiar Zapteryx brevirostris. Foram testadas as concentrações de 21,25; 42,50; 85,00 e 170,00 mg L-1 (1:5 de álcool absoluto). A concentração de 85,0 mg L-1 de eugenol foi a mais adequada para a espécie, permitindo uma janela de trabalho de até trezentos segundos com o animal não respondendo ao manejo.

Use of eugenol for anesthesia of lesser guitarfish Zapteryx brevirostris (Rhinobatidae).

Anesthesia can be utilized as a non-lethal procedure to allow easy handling of teleosts and elasmobranchs in captivity or in the wild. For this, anesthetic protocols need to be established according to the species. The aim of this study was to determine the ideal concentration of eugenol for anesthesia of Zapteryx brevirostris. Four concentrations were tested: 21.25, 42.50, 85.00 and 170.00 mg L-1 (ratio of 1:5 with absolute ethanol). The perfect concentration of eugenol for this species was 85.0 mg L-1 , which enabled up to 300 seconds of work on the fish, without any response to handling.

Hyptis pectinata essential oil: chemical composition and anti-Streptococcus mutans activity.

OBJECTIVES: The aim of the present study was to evaluate the anti-Streptococcus mutans activity of Hyptis pectinata essential oil, and present its promising potential against oral diseases. MATERIALS AND METHODS: The essential oil of H. pectinata was obtained by hydrodistillation from dried leaves and analyzed by GC / MS. The effectiveness of this essential oil regarding the antimicrobial activity against several S. mutans strains was investigated by the agar diffusion and microdilution methods, and chlorohexidine was used as a standard control. RESULTS: The H. pectinata essential oil exhibited considerable inhibitory effect against either all the clinical isolates obtained from patients' saliva or the ATCC strains tested, with minimum inhibitory and bactericidal concentrations of 200 microg ml(-1). The study also compared the efficiency of the emulsifying agents Tween 20, Tween 80, dimethyl sulfoxide and propylene glycol in H. pectinata essential oil when tested against S. mutans. The data obtained confirmed the better inhibitory effect of the oil when using all tested diluents, although Tween 80 seemed to be more suitable for emulsification. CONCLUSION: According to our results, H. pectinata essential oil can be considered a promising alternative to chlorhexidine for the control of oral bacteria-related diseases and hygiene.