Remote sensing in the leaf spectral characterization of the Hesperozygis ringens, an endangered species

The present study aimed to determine the reflectance pattern of Hesperozygis ringens leaves with the aid of Remote Sensing. Therefore, a spectroradiometer that operates in the continuous spectral range from 400 to 900 nm of the electromagnetic spectrum was used, with a resampled precision of 1 nm. The reflectance measurement was collected in situ. Four records were obtained. A spectral curve was created from the means of measurements in each sample. In the blue region, reflectance values between 0.0116696 and 0.0399550 were found. In the red region, the reflectance oscillated between 0.0438487 and 0.1095826. In the green region, the reflectance values ranged between 0.0405677 and 0.1001319. In the near infrared region, the oscillation of reflectance values occurred between 0.1163483 and 0.4655269. In the present study, it was possible to determine the reflectance pattern of H. ringens leaves using geotechnologies. It is hoped that the results found will stimulate future research in order to identify and monitor plant populations with Remote Sensing.Hesperozygis ringens is a species that stands out for the production of essential oil. No reports on the leaf spectral characterization of the species have been found. This study aimed to determine the reflectance pattern of Hesperozygis ringens leaves with the aid of Remote Sensing. Therefore, a spectroradiometer that operates in the continuous spectral range from 400 to 900 nm of the electromagnetic spectrum was used, with a resampled precision of 1 nm. The reflectance measurement was collected in situ. Four records were obtained. A spectral curve was created from the means of measurements in each sample. In the blue region, reflectance values between 0.0116696 and 0.0399550 were found. In the red region, the reflectance oscillated between 0.0438487 and 0.1095826. In the green region, the reflectance values ranged between 0.0405677 and 0.1001319. In the near-infrared region, the oscillation of reflectance values occurred between 0.1163483 and 0.4655269. The results indicate the effectiveness of the use of geotechnologies to carry out the spectral characterization of the H. ringens leaf.  Further studies are expected to identify and monitor plant populations with Remote Sensing

POTENCIAL DAS PLANTAS NATIVAS BRASILEIRAS PARA O DESENVOLVIMENTO DE FITOMEDICAMENTOS TENDO COMO EXEMPLO LIPPIA ALBA (MILL.) N. E. BROWN (VERBENACEAE)

O artigo aborda a potencialidade das plantas nativas brasileiras para o desenvolvimento de fármacos e matérias-primasfarmacêuticas. Aspectos relacionados à biodiversidade, à aceitabilidade do uso de plantas medicinais, ao mercado econômi-co, ao processo de desenvolvimento de fitomedicamentos ou fitoterápicos, bem com alguns tópicos sobre  a legislaçãoenvolvida são abordados.  Para mostrar esse potencial,  Lippia alba (Mill.) N. E. Brown (Verbenaceae), uma espéciemedicinal nativa conhecida popularmente como erva-cidreira ou falsa-melissa, é utilizada como exemplo. Alguns usospopulares, constituintes fitoquímicos, atividades farmacológicas e estudos agronômicos da planta são apresentados

EFEITO DA SAZONALIDADE SOBRE O RENDIMENTO DO ÓLEO ESSENCIAL DE Piper gaudichaudianum KUNTH

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.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

Nectandra grandiflora By-Products Obtained by Alternative Extraction Methods as a Source of Phytochemicals with Antioxidant and Antifungal Properties

Nectandra grandiflora Nees (Lauraceae) is a Brazilian native tree recognized by its durable wood and the antioxidant compounds of its leaves. Taking into account that the forest industry offers the opportunity to recover active compounds from its residues and by-products, this study identifies and underlines the potential of natural products from Nectandra grandiflora that can add value to the forest exploitation. This study shows the effect of three different extraction methods: conventional (CE), ultrasound-assisted (UAE) and microwave-assisted (MAE) on Nectandra grandiflora leaf extracts (NGLE) chemical yields, phenolic and flavonoid composition, physical characteristics as well as antioxidant and antifungal properties. Results indicate that CE achieves the highest extraction phytochemical yield (22.16%), but with similar chemical composition to that obtained by UAE and MAE. Moreover, CE also provided a superior thermal stability of NGLE. The phenolic composition of NGLE was confirmed firstly, by colorimetric assays and infrared spectra and then by chromatographic analysis, in which quercetin-3-O-rhamnoside was detected as the major compound (57.75–65.14%). Furthermore, the antioxidant capacity of the NGLE was not altered by the extraction methods, finding a high radical inhibition in all NGLE (>80% at 2 mg/mL). Regarding the antifungal activity, there was observed that NGLE possess effective bioactive compounds, which inhibit the Aspergillus niger growth.This research was financially supported by the Department of Education of Basque Government (IT1008-16) and by Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq process 454447/2014-0). Authors would like to thanks the CNPq for research grants received by Berta Maria Heinzmann, Ph.D. scholarship (process 203796/2014-4) granted to Daniela Thomas da Silva and the Basque Government for scholarship of young researchers training granted to Rene Herrera

Seasons influence on content, yield and chemical composition of Origanum majorana L. essential oil

The aim of this study was to determine the season that provides the highest production and best quality of marjoram (Origanum majorana L.) essential oil in summer and winter transplants. Two experiments were performed in a protected cultivation, the first with transplantation in summer and the second with transplantation in winter, with a completely randomized design with four treatments, being the seasons of the year. Content, yield and chemical composition of the essential oil were determined. The essential oil was extracted by hydrodistillation and analyzed by gas chromatography. In the summer transplant the essential oil content and yield were higher in the summer and spring seasons. In the winter transplant the oil content was higher in the summer season and the yield in the summer and in spring. Carvacrol was the major component of marjoram essential oil regardless of harvest and transplant season. Of the other main compounds, only terpinolene was detected in all samples analyzed, with the other essential oil components varying between transplant and harvest seasons. The highest production of marjoram essential oil is obtained in summer and spring harvests from plants transplanted in summer and winter. The major components of marjoram essential oil are carvacrol and terpinolene

Óleos essenciais e eugenol como anestésico para serrasalmus rhombeus

This study evaluated the periods of time of anesthetic induction and recovery of Serrasalmus rhombeus exposed to essential oils (EOs) of Aloysia triphylla and Lippia alba and eugenol, as well as if these anesthetics can be used for transport of this species through analysis of swimming behavior. Fish were placed in aquaria containing different concentrations of A. triphylla EO or L. alba EO or eugenol, posteriorly were transferred to aquaria containing only water to evaluate the recovery time. In the second experiment, behavior was analyzed during exposure to A. triphylla EO, L. alba EO or eugenol at 5 or 10 μL L-1. The evaluations were carried out at 0, 1, 5, 10 and 15 min of exposure. Fish exposed to 150, 200 and 50 μL L-1 of A. triphylla EO, L. alba EO and eugenol, respectively, showed anesthetic induction time lower than 3 min and recovery time lower than 10 min. Concentrations of 50 μL L-1 of both EOs and 25 μL L-1 eugenol caused only sedation. Exposure to 5 and 10 μL L-1 EOs and eugenol decreased fish swimming time. Both EOs and eugenol were effective for anesthesia and can be used for transport of S. rhombeus. © 2018, Instytut Technologii Drewna. All rights reserved

Essential Oils as Stress-Reducing Agents for Fish Aquaculture: A Review

In fish, stressful events initiate a hormone cascade along the hypothalamus-pituitaryinterrenal and hypothalamus-sympathetic-chromaffin (HSC) axis to evoke several physiological reactions in order to orchestrate and maintain homeostasis. Several biotic and abiotic factors, as well as aquaculture procedures (handling, transport, or stocking density), activated stress system inducing negative effects on different physiological processes in fish (growth, reproduction, and immunity). In order to reduce these consequences, the use of essential oils (EOs) derived from plants has been the focus of aquaculture studies due to their diverse properties (e.g., anesthetic, antioxidant, and antimicrobial), which have been shown to reduce biochemical and endocrine alterations and, consequently, to improve the welfare status. Recently, several studies have shown that biogenic compounds isolated from different EOs present excellent biological activities, as well as the nanoencapsulated form of these EOs may potentiate their effects. Overall, EOs presented less side effects than synthetic compounds, but their stress-reducing efficacy is related to their chemical composition, concentration or chemotype used. In addition, their species-specific actions must be clearly established since they can act as stressors by themselves if their concentrations and chemotypes used are not suitable. For this reason, it is necessary to assess the effect of these natural compound mixtures in different fish species, from marine to freshwater, in order to find the ideal concentration range and the way for their administration to obtain the desired biological activity, without any undesired side effects. In this review, the main findings regarding the use of different EOs as stress reducers will be presented to highlight the most important issues related to their use to improve fish welfare in aquaculture

Stress-reducing and anesthetic effects of the essential oils of aloysia triphylla and lippia alba on serrasalmus eigenmanni (Characiformes: Serrasalmidae)

Anesthetic effect of Aloysia triphylla and Lippia alba essential oils (EOs) in the Amazonian fish Serrasalmus eigenmanni was evaluated. The fish were placed in aquaria containing A. triphylla or L. alba EOs (25 to 200 µL L-1). Then, fish were transferred to aquaria containing EO-free water to evaluate their recovery time. In another experiment, fish were transferred to aquaria containing A. triphylla or L. alba EOs (3 to 10 µL L-1) and swimming behavior was analyzed for up to 240 min of exposure. Water samples were collected at 0 and 240 min and blood samples were collected at 240 min. Tested concentrations induced all stages of anesthesia, except 25 µL L-1 A. triphylla EO and 50 µL L-1 L. alba EO, which only induced sedation. Prolonged exposure to both EOs reduced swimming time compared to the control at all evaluated times. The fish exposed to 3 µL L-1 A. triphylla EO showed a lower net K+ efflux compared to ethanol-exposed fish; in those exposed to 5 µL L-1, ammonia excretion was reduced. The blood parameters did not show significant differences between treatments. In conclusion, both EOs can be used as anesthetics and sedatives for transport of S. eigenmanni. © 2019 Sociedade Brasileira de Ictiologia

Variabilidade sazonal e biossíntese de terpenóides presentes no óleo essencial de Lippia alba (Mill.) N. E. Brown (Verbenaceae)

The essential oil of the leaves of Lippia alba chemotype linalool-1,8-cineol was extracted by hidrodistillation at different seasons and analyzed by GC/MS. Qualitative and quantitative variations in regard to the period of harvesting have been performed and the results were correlated with meteorological data. The essential oil yield varied from 0.33 to 0.67%. The chemical diversity of the constituents increased throughout the year, being 1,8-cineol and linalool the major components. Possible biosynthetic routes of mono and sesquiterpenoids present in the essential oil are discussed