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

TOXICITY OF TAGETES MINUTA ESSENTIAL OIL IN SILVER CATFISH (RHAMDIA QUELEN)

Objective: Evaluation of Tagetes minuta L. essential oil (EOTM) toxicity in the silver catfish Rhamdia quelen.Methods: The EOTM extracted by hydrodistillation was identified qualitatively based on retention indices and the mass spectrum of its components by gas chromatography-mass spectrometry (GC-MS) and quantified by GC with flame ionization detector. Fish were exposed to 0, 50, 100, 200 mg l-1 EOTM and ethanol (1.5 ml) (n = 10 each concentration) and mortality observed after 24, 48 and 96 h (h).Results: The EOTM presented as the main constituents: di-hidrotagetone (7.66 %), Z-tagetone (29.50%) and E-tagetone (40.37%). Silver catfish mortality was 10% after 96 h at 50 mg l-1, 70 and 80% after 24 and 96 h, respectively, at 100 mg l-1 and 80, 90 and 100% after 24, 48 and 96 h, respectively, at 200 mg l-1.Conclusion: The use of EOTM is not recommended in fish farming at the concentrations measured in this study due to its toxic action.Keywords: Medicinal plants, Fish farming, Toxic effect, Cloves marigoldÂ

ÓLEOS ESSENCIAIS DE Blepharocalyx, Nectandra e Piper: ATIVIDADE SOBRE FUNGOS APODRECEDORES DE MADEIRA

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

Robust estimation of bacterial cell count from optical density

Optical density (OD) is widely used to estimate the density of cells in liquid culture, but cannot be compared between instruments without a standardized calibration protocol and is challenging to relate to actual cell count. We address this with an interlaboratory study comparing three simple, low-cost, and highly accessible OD calibration protocols across 244 laboratories, applied to eight strains of constitutive GFP-expressing E. coli. Based on our results, we recommend calibrating OD to estimated cell count using serial dilution of silica microspheres, which produces highly precise calibration (95.5% of residuals <1.2-fold), is easily assessed for quality control, also assesses instrument effective linear range, and can be combined with fluorescence calibration to obtain units of Molecules of Equivalent Fluorescein (MEFL) per cell, allowing direct comparison and data fusion with flow cytometry measurements: in our study, fluorescence per cell measurements showed only a 1.07-fold mean difference between plate reader and flow cytometry data

Surface sterilization effect on germination and seeds incidence of fungi of forest species

O objetivo deste estudo foi testar tratamentos de assepsia e sua influência na germinação e sanidade de sementes de quatro espécies florestais: Bauhinia forficata, Cedrela fissilis, Parapiptadenia rigida e Senegalia bonariensis. As sementes foram submetidas aos seguintes tratamentos: controle (T0); NaClO 1% por 3 min (T1); NaClO 2% por 1 min + 1 enxágue com água destilada (T2); álcool 70% por 1 min + triplo enxágue em água destilada + NaClO 0,5% por 1 min + triplo enxágue com água destilada (T3); Lysoform® por 1 min (T4); e álcool 70% por 1 min + NaClO 1% por 1 min + 1 enxágue com água destilada por 1 min (T5). Após, as sementes foram submetidas ao teste de germinação, sendo registrado comprimento, massa fresca e massa seca de plântulas, e teste de sanidade. Para B. forficata recomenda-se o tratamento T2, com aumento do potencial germinativo e comprimento de plântulas, sendo o mesmo recomendado para C. fissilis para aumento da germinação e redução da incidência de Fusarium sp.; todos os tratamentos de assepsia reduzem a incidência de fungos de armazenamento em P. rigida, porém não há influência sobre a germinação; e para S. bonariensis não há necessidade de assepsia. Os tratamentos de assepsia recomendados podem ser utilizados rotineiramente em sementes das espécies florestais estudadas.The aim of this study was to test treatments for sterilization and its influence on germination and health of seeds and seedlings of four forest species: Bauhinia forficata, Cedrela fissilis, Parapiptadenia rigida and Senegalia bonariensis. The seeds were subjected to the following treatments: control without treatment (T0); sodium hypochlorite 1% for 3 min (T1); sodium hypochlorite 2% for 1 min + one rinse with distilled water (T2); alcohol 70% for 1 min + triple rinse with distilled water + sodium hypochlorite 0.5% for 1 min + triple rinse with distilled water (T3); Lysoform ® for 1 min (T4); alcohol 70% for 1 min + sodium hypochlorite 1% for 1 min + one rinse with distilled water for 1 min (T5). Seeds were subjected to germination tests and we evaluate length of seedlings, fresh and dry weight, and sanity test. T2 is recommended for B. forficata presenting increase on germination potential and on seedling length; the same treatment is recommended for C. fissilis to increase germination and reduction of Fusarium sp. incidence; all aseptic treatments reduced incidence of P. rigida storage pathogen, however, there was no influence on germination; and seeds of S. bonariensis do not need to be sterilized. The recommended surface sterilization treatments could be routinely used in seeds of the studied species

Esential oil of Hesperozygis ringens alters the expression of pituitary hormones and energy metabolism in catfish R. quelen

Trabajo presentado en el VI Congresso da Sociedade Brasileira de Aquicultura e Biologia Aquática (Aquaciência), celebrado en Foz do Iguaçu (Brasil) del 1 al 5 de septiembre de 2014.N

Relaxing effect of eugenol and essential oils in Pomacea 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