Biochemical parameters of silver catfish (Rhamdia quelen) after transport with eugenol or essential oil of Lippia alba added to the water / Parâmetros bioquímicos do jundiá (Rhamdia quelen) após transporte com eugenol ou óleo essencial de Lippia alba adicionado à água

Abstract The transport of live fish is a routine practice in aquaculture and constitutes a considerable source of stress to the animals. The addition of anesthetic to the water used for fish transport can prevent or mitigate the deleterious effects of transport stress. This study investigated the effects of the addition of eugenol (EUG) (1.5 or 3.0 µL L-1) and essential oil of Lippia alba (EOL) (10 or 20 µL L-1) on metabolic parameters (glycogen, lactate and total protein levels) in liver and muscle, acetylcholinesterase activity (AChE) in muscle and brain, and the levels of protein carbonyl (PC), thiobarbituric acid reactive substances (TBARS) and nonprotein thiol groups (NPSH) and activity of glutathione-S-transferase in the liver of silver catfish (Rhamdia quelen; Quoy and Gaimard, 1824) transported for four hours in plastic bags (loading density of 169.2 g L-1). The addition of various concentrations of EUG (1.5 or 3.0 µL L-1) and EOL (10 or 20 µL L-1) to the transport water is advisable for the transportation of silver catfish, since both concentrations of these substances increased the levels of NPSH antioxidant and decreased the TBARS levels in the liver. In addition, the lower liver levels of glycogen and lactate in these groups and lower AChE activity in the brain (EOL 10 or 20 µL L-1) compared to the control group indicate that the energetic metabolism and neurotransmission were lower after administration of anesthetics, contributing to the maintenance of homeostasis and sedation status.

Resumo O transporte de peixes vivos é uma prática rotineira na aquicultura e constitui uma fonte considerável de estresse para os animais. A adição de anestésicos na água utilizada para o transporte de peixes pode prevenir ou mitigar os efeitos nocivos do estresse de transporte. Este estudo investigou os efeitos da adição de eugenol (EUG) (1,5 ou 3,0 mL L-1) e óleo essencial de Lippia alba (OEL) (10 ou 20 mL L-1) em parâmetros metabólicos (níveis de glicogênio, lactato e proteína total) no fígado e músculos, a atividade da acetilcolinesterase (AChE) no músculo e no cérebro, e os níveis de proteína carbonil (PC), ácido tiobarbitúrico (TBARS) e grupos tióis não proteicos (NPSH) e atividade da glutationa-S-transferase no fígado de jundiás (Rhamdia quelen; Quoy e Gaimard, 1824) transportados por quatro horas em sacos plásticos (densidade de carga de 169,2 g L-1). A adição de várias concentrações de EUG (1,5 ou 3,0 mL L-1) e OEL (10 ou 20 mL L-1) na água de transporte é aconselhável para o transporte do jundiá, uma vez que ambas concentrações destas substâncias aumentaram os níveis do antioxidante NPSH e diminuíram os níveis de TBARS no fígado. Além disso, os níveis mais baixos de glicogénio e lactato no fígado destes grupos e menor atividade de AChE no cérebro (EOL 10 ou 20 mL L-1) em comparação com o grupo controle indicam que o metabolismo energético e neurotransmissão foram menores após a administração dos anestésicos, contribuindo para a manutenção do estado de homeostase e sedação.

Seasonal variability of the essential oil of Hesperozygis ringens (Benth.) Epling. / Variabilidade sazonal do óleo essencial de Hesperozygis ringens (Benth.) Epling.

Abstract This study was developed to evaluate the effect of seasonality on the yield and chemical composition of the essential oil (EO) of Hesperozygis ringens (Benth.) Epling, a native species from the Brazilian Pampa. Leaves were collected from four specimens of a single population in each of the four seasons for a year and were extracted in triplicate by hydro-distillation for 2 hours. The yield of EO (% w/w) was calculated on fresh weight basis (FWB), and the 16 oil samples were analyzed by gas chromatography coupled to mass spectrometry (GC-MS) and gas chromatography with flame ionization detector (GC-FID). Hierarchical Cluster Analysis (HCA) and Principal Component Analysis (PCA) were used as statistical tools to evaluate differences in chemical composition. The highest yields were obtained in autumn, spring and summer (2.32-4.38%), while the lowest yields were detected in winter, ranging from 1.15 to 1.91%. Oxygenated monoterpenoids were the predominant class of chemical constituents in the EO obtained in all seasons, showing the highest contents in autumn and summer, and pulegone was identified as a major compound, whose contents varied between 54.13 and 81.17%. The EO samples were divided into three chemical groups by HCA and PCA and were assigned to the same group, except for the three samples gathered in winter. The results showed a seasonal influence on the yield and chemical composition of the EO.

Resumo Este estudo foi desenvolvido a fim de avaliar o efeito da sazonalidade no rendimento e composição química do óleo essencial (OE) de Hesperozygis ringens (Benth.) Epling., uma espécie nativa do Pampa brasileiro. Folhas foram coletadas de quatro indivíduos de uma mesma população, em cada uma das quatro estações de um ano, e foram extraídas em triplicada por hidrodestilação durante 2 horas. O rendimento do OE (% m/m) foi calculado considerando a base fresca (BF) e as 16 amostras de óleo foram analisadas por cromatografia gasosa acoplada à espectrometria de massas (CG-EM) e cromatografia gasosa com detector de ionização de chamas (CG-DIC). Análise Hierárquica de Cluster (AHC) e Análise de Componentes Principais (ACP) foram utilizadas como ferramentas estatísticas para avaliar as diferenças na composição química. Os maiores rendimentos foram obtidos no outono, primavera e verão (2,32-4,38%), enquanto que os menores foram detectados no inverno, variando de 1,15 até 1,91%. Os monoterpenoides oxigenados foram a classe predominante dos constituintes do OE obtido em todas as estações, apresentando os maiores teores no outono e no verão, e a pulegona foi identificada como o constituinte majoritário, cujos teores variaram entre 54,13 e 81,17%. As amostras de OE foram divididas em três grupos químicos por AHC e ACP e foram classificadas no mesmo grupo, com exceção de três amostras coletadas no inverno. Os resultados demonstraram influência sazonal no rendimento e na composição química dos OE.

Effect of (+)-dehydrofukinone on GABAA receptors and stress response in fish model

(+)-Dehydrofukinone (DHF) is a major component of the essential oil of Nectandra grandiflora (Lauraceae), and exerts a depressant effect on the central nervous system of fish. However, the neuronal mechanism underlying DHF action remains unknown. This study aimed to investigate the action of DHF on GABAA receptors using a silver catfish (Rhamdia quelen) model. Additionally, we investigated the effect of DHF exposure on stress-induced cortisol modulation. Chemical identification was performed using gas chromatography-mass spectrometry and purity was evaluated using gas chromatography with a flame ionization detector. To an aquarium, we applied between 2.5 and 50 mg/L DHF diluted in ethanol, in combination with 42.7 mg/L diazepam. DHF within the range of 10-20 mg/L acted collaboratively in combination with diazepam, but the sedative action of DHF was reversed by 3 mg/L flumazenil. Additionally, fish exposed for 24 h to 2.5-20 mg/L DHF showed no side effects and there was sustained sedation during the first 12 h of drug exposure with 10-20 mg/L DHF. DHF pretreatment did not increase plasma cortisol levels in fish subjected to a stress protocol. Moreover, the stress-induced cortisol peak was absent following pretreatment with 20 mg/L DHF. DHF proved to be a relatively safe sedative or anesthetic, which interacts with GABAergic and cortisol pathways in fish.

Effects of anesthesia with the essential oil of Ocimum gratissimum L. in parameters of fish stress / Efeitos da anestesia com o óleo essencial de Ocimum gratissimum L. em parâmetros de estresse de peixes

RESUMO: The effects of anesthesia with the essential oil of Ocimum gratissimum (EOO) in parameters of stress after handling were investigated in silver catfish (Rhamdia quelen). EOO was obtained from the aerial parts by hydrodistillation. Juveniles were anesthetized with 70 or 300 mg L-1 EOO and submitted to air exposure for 1 minute. The fishes were sampled immediately or transferred to anesthetic-free aquaria until sampling. In the first experiment, juveniles had their blood collected at 0, 1, 4, and 8 h after handling to assay plasma cortisol and blood glucose levels. The unanesthetized animals were restrained manually for blood collection. In the second experiment, water samples of the recovery aquaria were collected to evaluate net ion fluxes at 0 - 4 h and 4 - 8 h. Water and ethanol controls were also performed under the same conditions. The results showed that the cortisol levels did not differ among the treatments. Hyperglycemia was verified in fish exposed to 70 and 300 mg L-1 EOO at 1 h and 4 h after handling. After 8 h, cortisol and glucose concentrations were lower or similar than those from immediately after handling for all treatments. EOO anesthesia prevented Na+ efflux observed in the control groups in both flux periods. There were net Cl- and K+ effluxes at 0 - 4 h and influxes at 4 - 8 h after handling in most treatments, and these fluxes did not differ among the treatments. The results suggest that EOO did not impair stress recovery and did not act as an additional handling stressor in silver catfish.

RESUMO: Os efeitos da anestesia com o óleo essencial de Ocimum gratissimum (EOO) em parâmetros de estresse após manuseio foram investigados em jundiás (Rhamdia quelen). EOO foi obtido a partir das partes aéreas por hidrodestilação. Os juvenis foram anestesiados com 70 ou 300 mg L-1 de EOO e expostos ao ar por 1 minuto. Os peixes foram amostrados imediatamente ou transferidos para aquários sem anestésico até amostragem. No primeiro experimento, os juvenis tiveram seu sangue coletado em 0, 1, 4, e 8 h após manuseio para avaliar os níveis de cortisol e glicemia. Os animais não anestesiados foram contidos manualmente para coleta sanguínea. No segundo experimento, amostras de água foram coletadas do aquário de recuperação dos animais para avaliação do fluxo iônico entre 0 - 4 h e 4 - 8 h. Grupos controles em água e etanol também foram realizados sobre as mesmas condições. Os resultados demonstraram que os níveis de cortisol não diferiram entre os tratamentos. Hiperglicemia foi detectada em peixes expostos a 70 e 300 mg L-1 de EOO em 1 h e 4 h após o manuseio. Após 8 h, os teores de cortisol e glicose foram menores ou similares aqueles imediatamente após o manuseio para todos os tratamentos. A anestesia com EOO preveniu o efluxo de Na+ observado para os grupos controle em ambos os períodos avaliados. Ocorreram efluxos de Cl- and K+ entre 0 - 4 h e influxos entre 4 - 8 h após o manuseio para a maioria dos tratamentos, e estes eventos não diferiram entre os tratamentos. Os resultados sugerem que o EOO não prejudica a recuperação do animal frente ao evento estressor ou atua como estressor adicional ao manuseio em jundiás.

Sedative and anesthetic activities of the essential oils of Hyptis mutabilis (Rich.) Briq. and their isolated components in silver catfish (Rhamdia quelen)

This study evaluated the sedative and anesthetic effects of the essential oils (EO) of Hyptis mutabilis (Rich.) Briq. and their isolated components on silver catfish (Rhamdia quelen). Quantitative chemical differences between the EOs obtained from leaves and inflorescences were verified, and a new chemotype rich in globulol was described. Although there were no significant differences in the time of induction for sedation and anesthesia between the EOs, only the leaf EO at 344 mg/L anesthetized all fish without side effects. Fractionation of the leaf EO was carried out by column chromatography. The isolated compounds [(+)-1-terpinen-4-ol and (-)-globulol] showed different activity from that detected for the leaf EO in proportional concentrations and similar sedation to a eugenol control at 10 mg/L. However, fish exposed to 1-terpinen-4-ol (3 and 10 mg/L) did not remain sedated for 30 min. Anesthesia was obtained with 83-190 mg/L globulol, but animals showed loss of mucus during induction and mortality at these concentrations. Synergism of the depressor effects was detected with the association of globulol and benzodiazepine (BDZ), compared with either drug alone. Fish exposed to BDZ or globulol+BDZ association showed faster recovery from anesthesia in water containing flumazenil, but the same did not occur with globulol. In conclusion, the use of globulol in aquaculture procedures should be considered only at sedative concentrations of 10 and 20 mg/L, and its mechanism of action seems not to involve the GABAA-BDZ system.

Composition and evaluation of the antimicrobial activity of the essential oil of Senecio selloi Spreng DC / Composição e avaliação da atividade antimicrobiana do óleo essencial de Senecio selloi Spreng DC

The essential oil of the aerial parts of Senecio selloi Spreng. DC. was extracted by hydrodistillation and analyzed by GC/MS. Nineteen compounds were identified, representing 99.9% of the total. The main compounds were found to be sesquiterpene hydrocarbons (71.3%), most of them with a bisabolane skeleton (59.4%). The major constituent was α-zingiberene (54%), followed by monoterpene α-isolimonene (16%). The essential oil was also tested against two Gram-positive and two Gram-negative bacterial species, three yeasts, and an algae. From the strains assayed, only Bacillus subtilis ATCC 6633 showed susceptibility (MIC and MBC = 4400 µg/mL) to the essential oil.

O óleo essencial das partes aéreas de Senecio selloi Spreng DC. foi extraído por hidrodestilação e analisado por CG/EM. Dezenove constituintes foram identificados, representando 99,9% do total. Os principais compostos fornecidos foram sesquiterpenos hidrocarbonetos (71,3%), a maioria destes com esqueleto bisabolano (59,4%). O constituinte majoritário foi a-zingibereno (54%), seguido do monoterpeno a-isolimoneno (16%). O óleo essencial foi testado contra duas cepas Gram-positivas e duas Gram-negativas, três fungos e uma alga. De todas as linhagens testadas somente Bacillus subtilis ATCC 6633 mostrou suscetibilidade (CIM e CBM = 4400 µg/mL) para o óleo essencial.

Participation of the GABAergic system in the anesthetic effect of Lippia alba (Mill.) N.E. Brown essential oil

The objective of this study was to identify the possible involvement of the GABAergic system in the anesthetic effect of Lippia alba essential oil (EO). We propose a new animal model using silver catfish (Rhamdia quelen) exposed to an anesthetic bath to study the mechanism of action of EO. To observe the induction and potentiation of the anesthetic effect of EO, juvenile silver catfish (9.30 ± 1.85 g; 10.15 ± 0.95 cm; N = 6) were exposed to various concentrations of L. alba EO in the presence or absence of diazepam [an agonist of high-affinity binding sites for benzodiazepinic (BDZ) sites coupled to the GABA A receptor complex]. In another experiment, fish (N = 6) were initially anesthetized with the EO and then transferred to an anesthetic-free aquarium containing flumazenil (a selective antagonist of binding sites for BDZ coupled to the GABA A receptor complex) or water to assess recovery time from the anesthesia. In this case, flumazenil was used to observe the involvement of the GABA-BDZ receptor in the EO mechanism of action. The results showed that diazepam potentiates the anesthetic effect of EO at all concentrations tested. Fish exposed to diazepam and EO showed faster recovery from anesthesia when flumazenil was added to the recovery bath (12.0 ± 0.3 and 7.2 ± 0.7, respectively) than those exposed to water (9.2 ± 0.2 and 3.5 ± 0.3, respectively). In conclusion, the results demonstrated the involvement of the GABAergic system in the anesthetic effect of L. alba EO on silver catfish.

Caracterização físico-química e biológica do caule de Caesalpinia ferrea Mart. / Physico-chemical and biological characterization of Caesalpinia ferrea Mart. stems

Visando estabelecer parâmetros para o controle da qualidade do caule de Caesalpinia ferrea Mart. (Caesalpiniaceae), foram realizados testes preconizados pela Farmacopéia Brasileira IV e pela Organização Mundial da Saúde para a avaliação da pureza, através das determinações de materiais estranhos, cinzas totais, cinzas insolúveis em ácido, umidade, ensaios-limites de cloretos e sulfatos, além da pesquisa de contaminantes microbianos no material pulverizado. Para a caracterização dos constituintes, eventualmente presentes na droga vegetal, foram realizadas as determinações de taninos, dos índices de espuma, intumescimento e amargor e o teste de hemólise; também foi realizada a caracterização do extrato etanólico bruto e suas frações por cromatografia em camada delgada.

In order to establish parameters for the control quality of Caesalpinia ferrea Mart. stem, the drug was characterized by the methods described in Farmacopéia Brasileira IV and by the World Health Organization. The powdered plant material was submitted to the following tests for purity evaluation: foreign matter, total ash, acid insoluble ash, water content, chloride and sulfate limit assays, and microbiological contamination. Determination of haemolytic activity, foaming index, swelling index and bitterness index were done to characterize the constituents eventually present in the drug, as well as the characterization of the ethanolic crude extract and its fractions by thin-layer chromatography.