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This study aimed to use digital image processing to evaluate the antifungal activity of essential oils (EOs) from Blepharocalyx salicifolius (Myrtaceae), Nectandra grandiflora (Lauraceae), Nectandra megapotamica (Lauraceae) and Piper gaudichaudianum (Piperaceae) on wood decay fungi. A white-rot fungus, Trametes versicolor, and a brown-rot fungus, Gloeophyllum trabeum, were selected. The EOs were extracted by hydrodistillation and chemically characterized by gas chromatography coupled to mass spectrometry (GC-MS). The antifungal activity of the EOs was evaluated by the Petri plate diffusion test. The inhibition verification was calculated with the aid of digital image processing, using ImageJ software. The predominant compounds of the B. salicifolius and P. gaudichaudianum extractives were eucalyptol and dillapiol, respectively. For the species of Nectandra, bicyclogermacrene was the most representative constituent of the N. megapotamica EO, whereas dehydrofuquinone was the major constituent of the EOs from N. grandiflora leaves and fruits. The highest growth inhibition of T. versicolor was caused by N. megapotamica EO. The highest inhibition percentages of G. trabeum were provided by P. gaudichaudianum and B. salicifolius extractives. Digital image processing was an effective tool for the accurate analysis of fungal growth. A busca por produtos naturais que possam substituir preservantes da madeira sintéticos é crescente. Dentre estes produtos, estão os óleos essenciais (OEs). Portanto, o objetivo deste estudo foi avaliar a atividade antifúngica dos OEs de Blepharocalyx salicifolius, Nectandra grandiflora, Nectandra megapotamica e Piper gaudichaudianum, sobre os fungos apodrecedores de madeira Trametes versicolor e Gloeophyllum trabeum. Os OEs foram extraídos por hidrodestilação e foram caracterizados quimicamente. A atividade antifúngica dos OEs foi avaliada pelo teste de difusão em placas de Petri. A verificação da inibição foi calculada com auxílio do software ImageJ®. Os componentes majoritários dos OEs de B. salicifolius e P. gaudichaudianum foram eucaliptol e dilapiol, respectivamente. Biciclogermacreno foi o constituinte majoritário do óleo essencial (OE) de folhas de N. megapotamica, enquanto que a deidrofuquinona foi majoritária nos OEs de folhas e frutos de N. grandiflora. A maior inibição do crescimento de T. versicolor foi causada pelo OE de N. megapotamica, com 31,4%. Os maiores percentuais de inibição observados sobre o crescimento de G. trabeum foram proporcionados pelos extrativos de P. gaudichaudianum e B. salicifolius, com 13,9 e 7,5%, respectivamente. Contudo, o resultado deste último não diferiu dos demais OEs avaliados. Os resultados indicaram que o extrativo de espécie de Nectandra que apresentou maior efeito sobre T. versicolor foi N. megapotamica. Entretanto, este gênero não foi tão eficiente contra G. trabeum. Palavras-chave: biciclogermacreno; deidrofuquinona; dilapiol; eucaliptol; Gloeophyllum trabeum; Trametes versicolor. Blepharocalyx, Nectandra and Piper essential oils: activity on wood-decay fungi ABSTRACT: The search for natural products that can replace synthetic wood preservatives is growing. Among these products are essential oils (EOs). Therefore, the aim of this study was to evaluate the antifungal activity of EOs from Blepharocalyx salicifolius , Nectandra grandiflora , Nectandra megapotamica and Piper gaudichaudianum on the wood-rotting fungi Trametes versicolor and Gloeophyllum trabeum. The EOs were extracted by hydrodistillation and chemically characterized. The antifungal activity of the EOs was evaluated by the Petri dish diffusion test. The inhibition verification was calculated using ImageJ® software. The major components of the EOs of B. salicifolius and P. gaudichaudianum were eucalyptol and dillapiol, respectively. Bicyclogermacrene was the major constituent of N. megapotamica leaves essential oil (EO), while dehydrofuquinone was the major constituent of the EOs from N. grandiflora leaves and fruits. The highest growth inhibition of T. versicolor was caused by N. megapotamica EO, with 31.4%. The highest inhibition percentages of G. trabeum growth were provided by P. gaudichaudianum and B. salicifolius extractives, with 13.9 and 7.5%, respectively. However, the result of the latter did not differ from the other EOs evaluated. The results indicated that, from the extractives of Nectandra species, the greatest effect on T. versicolor was detected to N. megapotamica EO. However, this genus was not so efficient against G. trabeum. Keywords: bicyclogermacrene; dehydrofuquinone; dillapiole; eucalyptol; Gloeophyllum trabeum; Trametes versicolor.

This study aimed to evaluate the antifungal potential of the essential oil (EO) from Hesperozygis ringens leaves and its major compound pulegone against wood-decay fungi. In addition, their effect ...

The objective of this exploratory work was to analyze the yield and chemical composition of essential oils (EO) from Blepharocalyx salicifolius [BS] and from two pools of EO obtained from Nectandra megapotamica [NM1 and NM2], as well as to evaluate their antifungal properties against the fungi Pycnoporus sanguineus (white-rot) and Gloeophyllum trabeum (brown-rot). The EO were obtained by hydrodistillation and its components were identified by gas chromatography coupled to mass spectrometry (GC-MS) and quantified with flame ionization detection (GC-FID). For the evaluation of antifungal activity, the mycelial growth index (MGI) and the mycelial growth inhibition (GI) of BS were determined at concentrations of 1, 2 and 5 µL.mL-1, and 0.25; 0.5 and 1 µL.mL-1 for MN1 and NM2. The yield of EOs was 2.29% (BS), 0.14% (NM1) and 0.17% (NM2). The major components of BS EO were eucalyptol (63.44%) and β-caryophyllene (13.68%), from NM1 were bicyclogermacrene (16.14%) and α-pinene (15.93%), and for NM2, α-pinene (19.04%) and sabinene (16.66%). EO NM1 (1μL.mL-1) showed the best result for antifungal activity, inhibiting about 57.55 ± 0.68 % of P. sanguineus growth and 58.82 ± 0.78 % in the test with G. trabeum.

Nectandra megapotamica (Spreng.) Mez. it is a native tree species of the Atlantic Forest, commonly known as canela-preta. The species has some anti-inflammatory, antitumor and antirheumatic properties among others. In this work the use of frozen plant material for microscopy analysis was tested. In addition, the leaf morpho-anatomy of the species was characterized which allowed to perform a structural description and to identify structures of secretion and storage of essential oil. The plant material was prepared for analyzes in optical, fluorescence and scanning electron microscopy. The leaf anatomy shows glabrous epidermis, unistratified, paracytic stomata, absence of trichomes, polyhedral epidermal cells. Some typical family characteristics were observed as a closed arc-shaped bicollateral bundle vascular system and dorsiventral mesophyll. The structures of secretion and storage of essential oil were identified as secretory cavities.

Este estudo teve por objetivos avaliar o efeito da sazonalidade sobre o teor de óleo essencial (OE) presente nas folhas de Nectandra grandiflora Nees e determinar se a secagem do material vegetal à temperatura ambiente influencia o rendimento do OE. Para tanto, foi coletado material vegetal de 12 indivíduos ao longo de um ano, e o OE foi extraído separadamente de folhas frescas e folhas secas, pelo método de hidrodestilação. Paralelamente, 20 g de folhas frescas foram levados à estufa a 40 °C até peso constante, para determinação do teor de umidade, procedimento esse realizado para cada coleta, individualmente. O rendimento de OE das folhas (% m/m) foi calculado para o material vegetal fresco com base em massa de matéria seca, determinado considerando o teor de umidade, bem como para o material seco à temperatura ambiente. Os dados de rendimento foram analisados através do teste de Tukey (P

This review aims to conduct a historical analysis of the production chain of sheep in the Rio Grande do Sul, for this purpose we studied the market before the crisis laneira, the late 80s, and the return of productivity after the change in the focus of production. The sheep were introduced in Brazil in the sixteenth century, but only in the twentieth century the activity generated economic development in Rio Grande do Sul, in this period the main product was exploited wool. However, in the late 80s was the beginning of the crisis in the sector laneiro, mainly caused by an increase in inventories of wool from Australia, the marketing of synthetic fabrics and global crises and collapses. Currently identified is the return of the sheep production industry dedicated to meat eating as a result of factors such as the increased purchasing power of the population and adapt to new consumer habits that lead to appreciation for sheep meat. The trends for this market are promising. However, there are some barriers to growth, as the disorder of the sector and the lack of standardization of products. For the state to become major producer of sheep meat is necessary to organize the sector, from production to distribution channels.