RESUMO Piper gaudichaudianum Kunth (Piperaceae) é uma planta com ampla distribuição no território brasileiro. Além de sua importância ecológica, é utilizada na medicina popular e muitas de suas atividades biológicas já foram comprovadas. O objetivo deste trabalho foi verificar o efeito da sazonalidade sobre o teor de óleo essencial (OE) em folhas de Piper gaudichaudianum e averiguar a possível influência do processo de secagem do material vegetal no rendimento deste extrativo. Foram coletadas aleatoriamente folhas de indivíduos de uma população nativa de Santa Maria - RS, Brasil, ao longo de um ano. O OE foi extraído de folhas frescas e secas à temperatura ambiente pelo método de hidrodestilação. Quando verificada a presença de órgãos reprodutivos, os mesmos foram extraídos, a fim de examinar a sua influência no rendimento do OE de folhas. Para determinação do teor de umidade (TU%), 20 g de folhas e 10 g de órgãos reprodutivos foram secos separadamente em estufa a 50°C até peso constante. O rendimento de OE de folhas (% m/m) foi calculado para o material fresco com base na massa seca, considerando o TU%, bem como para o material seco à temperatura ambiente. Apenas pequenas variações sazonais nos teores de OE foram detectadas para as amostras analisadas, não havendo diferença estatística entre eles. O maior rendimento foi observado na primavera, tanto para o OE de folhas (1,61±0,09%), quanto de órgãos reprodutivos (5,17%), enquanto o menor teor de OE em folhas ocorreu no verão (1,32±0,14%), a única estação em que não houve a presença de órgãos reprodutivos. A ausência de diferença significativa entre os rendimentos indica que não houve variabilidade sazonal quantitativa na produção de OE em folhas desta população. Portanto, a coleta deste órgão vegetal pode ser realizada em qualquer época do ano visando à obtenção deste extrativo. Uma vez que não foi verificada diminuição do teor de OE durante o processo de secagem à temperatura ambiente, esse processamento pós-colheita poderá ser adotado.

ABSTRACT Piper gaudichaudianum Kunth (Piperaceae) is widely distributed throughout Brazil. In addition to its ecological importance, it is used in folk medicine and a great number of its biological activities have been already proved. Thus, the aim of this research was to investigate the effect of seasonality on the content of essential oil (EO) in leaves of Piper gaudichaudianum and ascertain the possible influence of the drying process of the plant material in the yield of this extractive. Leaves were randomly collected from individuals of a native population in Santa Maria, RS state, Brazil, along a year. The EO was extracted from fresh and dried leaves by hydrodistillation. When reproductive organs were observed, they were extracted in order to examine their influence on the yield of leaf EO. To determine the moisture content (MC%), 20 g of leaves and 10g of reproductive organs were dried separately in an oven at 50°C until constant weight. The yield of leaf EO (% w/ w) was calculated for the fresh material based on the dry weight considering the MC%, and for the dried material at room temperature. Only small seasonal variations in EO content was detected for the analyzed samples, with no statistical difference between them. The highest yield was observed in the spring for EO from the leaves (1.61 ± 0.09%), and from the reproductive organs (5.17%), while the lowest yields of leaf EO occurred in the summer (1.32 ± 0.14%), the only season which showed no presence of the reproductive organs. The absence of significant difference between the yields indicates no quantitative seasonal variability in production of EO in leaves of this population. However, yields did not differ statistically, indicating no seasonal variability of the EO content of the leaves of this population. Therefore, the collection of this plant organ can be performed at any time of the year in order to obtain this extractive. Since there was no decrease in the content of EO during the drying process at room temperature, this post-harvest processing can be adopted.

RESUMO O efeito anestésico dos óleos essenciais (OEs) da casca de Citrus x aurantium (OECA) e Citrus x latifolia (OECL) em jundiá Rhamdia quelen foi investigado. Os peixes foram expostos a diferentes concentrações de OECA e OECL para determinar o tempo de indução e recuperação da anestesia. Todos peixes expostos a 400, 600 ou 800 μL L−1 OECA e 300, 400 ou 500 μL L−1 OECL foram anestesiados. Outro grupo de peixes foi exposto aos OEs durante 8 h a 50, 100 ou 200 μL L−1. Peixes expostos ao etanol e aos OEs apresentaram VF maior que o grupo controle durante as 8 h de exposição. Os efluxos líquidos de Na+, K+, Cl− e a excreção de amônia foram significativamente menores nos peixes expostos a 50, 100 ou 200 μL L−1 dos OEs em comparação com o grupo controle. A mortalidade foi de 37% nos peixes expostos a 200 μL L−1 de ambos os OEs após 8 h. Os resultados sugerem que OECA e OECL são anestésicos e sedativos úteis para o jundiá, mas sua utilidade como alternativa para reduzir o estresse no transporte de peixes nas concentrações mais baixas testadas (50-100 μL L−1) necessita de estudos adicionais.

ABSTRACT This study investigated the anesthetic effect of the essential oils (EOs) from the peel of Citrus x aurantium (EOCA) and Citrus x latifolia (EOCL) on silver catfish Rhamdia quelen. Fish were exposed to different concentrations of EOCA and EOCL to determine time of anesthesia induction and recovery. Induction of anesthesia was observed in all fish exposed to 400, 600 or 800 μL L−1 EOCA and 300, 400 or 500 μL L−1 EOCL. Another group of fish were exposed for 8 h to 50, 100, or 200 μL L−1 of either EOs. Overall, fish exposed to ethanol and both EOs presented higher ventilatory frequencies (VF) than the control group throughout the 8 h of exposure. Net ion (Na+, K+ and Cl−) effluxes and ammonia excretion were significantly lower in fish exposed to 50, 100 or 200 μL L−1 of either EOs compared to control fish. Mortality was 37% in fish exposed to 200 μL L−1 of either EOs after 8 h. These findings suggest that EOCA and EOCL are useful anesthetics and sedatives for Rhamdia quelen, but their usefulness as alternatives to reduce stress in fish transportation at the lower concentrations tested (50-100 µL L−1) deserves further study.

RESUMO: Este estudo teve como objetivo avaliar os possíveis efeitos relaxantes e/ou moluscicidas do eugenol e óleos essenciais de Origanum majorana, Ocimum americanum, Hesperozygis ringens e Piper gaudichaudianum no gastrópode Pomacea canaliculata. Os compostos foram testados nas concentrações de 100, 250, 500 e 750µL L-1 para avaliar os efeitos relaxantes. Em um segundo experimento, os animais foram expostos a 10, 25 e 50µL L-1 por 24 horas aos óleos essenciais de H. ringens e P. gaudichaudianum para avaliação dos efeitos moluscicida. O eugenol e os óleos essenciais de O. majorana e O. americanum apresentaram efeito relaxante nas concentrações ≥250µL L-1, mas os óleos essenciais de H. ringens e P. gaudichaudianum não promoveram efeito relaxante ou moluscicida no tempo e concentrações estudadas. Portanto, apenas o eugenol e os óleos essenciais de O. majorana e O. americanum podem serem usados para fins de relaxamento em P. canaliculata.

ABSTRACT: This study evaluated the potential relaxing and/or molluscicidal effects of eugenol and essential oils of Origanum majorana, Ocimum americanum, Hesperozygis ringens, and Piper gaudichaudianum in the gastropod Pomacea canaliculata. Compounds were tested at concentrations of 100, 250, 500, and 750µL L-1 to evaluate the relaxing effects. In the second experiment, animals were exposed to 10, 25, and 50µL L-1 of essential oils of H. ringens and P. gaudichaudianum for a period of 24h for the evaluation of molluscicidal effects. Eugenol and essential oils of O. majorana and O. americanum showed relaxing effects at ≥250µL L-1, but the essential oils of H. ringens and P. gaudichaudianum did not promote relaxing or molluscicidal effects within the times and concentrations studied. Therefore, only eugenol and the essential oils of O. majorana and O. americanum can be used for relaxation purposes in P. canaliculata.

ABSTRACT This study describes a comparative analysis of the essential oil (EO) chemical composition of leaves and reproductive organs (inflorescences and fruits) of Piper gaudichaudianum during the seasons of a year in order to determine the best collection time and the most suitable plant organ to obtain this extractive. The chemical composition of EO obtained from fresh leaves was compared to the dried ones, to verify if the drying process interferes in the extractive quality. The leaves were collected from a native population of Santa Maria, RS, Brazil, twice in each season, in triplicate, while inflorescences and fruits were sampled when they were present. The EO was obtained by hydrodistillation of the different plant organs for 3 h. The 20 EO samples were analyzed by gas chromatography (GC) coupled to mass spectrometry and GC with flame ionization detector, in triplicate. Hierarchical cluster analysis (HCA) and principal components analysis (PCA) were performed to verify a possible formation of chemical groups (CG) and the cohesion among them. The phenylpropanoid dillapiole was the major constituent of the EO in all seasons and in all plant organs, and myristicin was observed only in reproductive organs. The EO samples of this population were divided into two CG by HCA and PCA, showing the variability in chemical composition between different plant organs, however there was no chemical variability due to seasonality and phenophases. Since the drying of the leaves did not alter the EO chemical composition, this post-harvest procedure can be used without compromising the extrative quality.

This study evaluated the seasonal influence on the yield and chemical composition of the essential oil (EO) of Nectandra megapotamica. Fresh young (YL) and old leaves (OL) obtained from three trees in each season (Nov/2010 to Sep/2011) collected in Santa Maria-RS were hydrodistilled in triplicate. The chemical composition was determined by the gas chromatography coupled to mass spectrometry (GC-MS) and the yield on dry basis was evaluated by two-way ANOVA (seasons, development stage). Spring (Sp) and summer (Su) showed higher average incomes (0.45 and 0.33%), which occurred when flowering, fruiting, and growth of YL and senescence of OL took place, while autumn (Au) presented the lowest yield (0.25%) during the rustification of OL. The highest yield was obtained for the YL in Sp (0.59%) and the lowest for the OL in Au (0.21%). The major constituents of the EO were independent from the season and were identified as α-pinene, bicyclogermacrene, β-pinene, germacrene D, and limonene. Seasonality and phenology influenced the production of EO probably due to morphological and metabolic alterations in the leaves as well as due to the needs of the tree, such as attraction and/or protection.

Este estudo analisou a composição química e o potencial anestésico do óleo essencial (OE) de Nectandra megapotamica em robalos-peva (Centropomus parallelus). Para a extração do OE por hidrodestilação, as folhas foram separadas em jovens (OE-J) ou velhas (OE-V) e a composição química foi determinada por CG-EM. O potencial anestésico foi acessado através da avaliação do tempo de indução e recuperação da anestesia e resposta ao estresse do procedimento anestésico e transporte. Foram realizados três experimentos: em primeiro lugar, quatro concentrações diferentes de cada OE foram testadas para avaliar o tempo de indução à anestesia e de recuperação; em segundo lugar, duas concentrações do OE-V foram testadas para avaliar os efeitos sobre os parâmetros de estresse (níveis plasmáticos de glicose, lactato, Na+ e K+) causados pelo procedimento anestésico; em terceiro lugar, os peixes foram transportados em sacos plásticos com duas concentrações do OE-V para avaliação da qualidade da água e mortalidade. Todos os experimentos foram realizados em peixes aclimatados à salinidade zero e 33. Os constituintes majoritários do OE-J e OE-V foram: biciclogermacreno (46,5/34,6%), α-pineno (26,8/26,2%), β-pineno (7,9/12,3%) e germacreno D (9,6/9,1%). Sedação leve foi alcançada com 30 °L L-1(1,3-3,2 min) e anestesia profunda a partir de 150 °L L-1(5,6-8,0 min) com ambos OEs. O tempo de recuperação variou entre 1-10 min.O OE-V não foi capaz de evitar o estresse do procedimento anestésico, evidenciado pelos elevados níveis plasmáticos de glicose e lactato observados em todos os grupos. Os níveis plasmáticos de Na+ e K+ não foram significativamente afetados pelos tratamentos. Durante o transporte, o OE-V não impediu a deterioração da qualidade da água e a mortalidade pós-transporte. Concluindo, o OE de Nectandra megapotamicaapresenta atividade anestésica em robalos-peva, mas não foi capaz de evitar o estresse do procedimento anestésico e transporte.

This study analyzed the chemical composition and anesthetic potential of essential oil (EO) of Nectandra megapotamica in fat snook (Centropomus parallelus). For the extraction of EO by hydrodistillation, leaves were separated in young (EO-Y) or old (EO-O), and the chemical composition of the EOs was determined by CG-MS. The anesthetic potential was assessed by the evaluation of induction and recovery time of anesthesia and stress response from anesthesia and transport. Three experiments were carried out: i) four different concentrations of each EO were tested to evaluate anesthesia induction and recovery time; ii) two concentrations of EO-O were tested for the evaluation of its effects on stress parameters (glucose, lactate, and Na+ and K+ plasma levels) caused by anesthesia; and iii) fish were transported in plastic bags, supplied with two concentrations of EO-O for the evaluation of water quality and mortality. All experiments were performed on fish acclimated to 0 and 33 ppt salinity. The main constituents of the Y and O-EOs were bicyclogermacrene (46.5/34.6%), α-pinene (26.8/26.2%), β-pinene (7.9/12.3%), and germacrene D (9.6/9.1%). Mild sedation was achieved at 30 °L L-1(1.3-3.2 min) and deep anesthesia at 150 °L L-1(5.6-8.0 min) with both EOs. The recovery time ranged from 1-10 min. The EO-O was not able to avoid the stress of anesthesia evidenced by elevated glucose and lactate plasma levels observed in all groups. Plasma levels of Na+ and K+ were not significantly affected by treatments. During transport, the use of EO-O did not prevent deterioration in water quality and the post-transport mortality. In conclusion, the EO of N. megapotamica has anesthetic activity in fat snook, but it was not able to prevent the stress of anesthesia and transport.