Growth and Biochemical Composition of Navicula sp. Cultivated at Two Light Intensities and Three Wavelengths

Many studies have reported that the exposure of microalgae cultures to red light increases the production of carbohydrates, while blue light promotes the production of protein. There are several studies about Navicula, however there are few, if any, studies of the combined effects of wavelength and light intensity on the biochemical composition of this genus In this study we evaluated the combined effect of three wavelengths: white (400-750nm), blue (430-480nm), and red (650-750nm), at two light intensities (50 and100 μmol/m2/sec) on the growth and biochemical composition of Navicula sp. cultured on a laboratory scale. The experiment was carried out under controlled conditions utilizing a factorial design 2x3 (light intensity and wavelength) with white light as the control. The cell concentration was measured daily. Dry biomass of filtered cells was incinerated at 450ºC in a muffle oven. The biochemical content was measured using micro methods. The cell concentration was higher with white light at both intensities (291,875 and 90,938 cells/mL at 50 and100 μmol photon/m2/sec, respectively). Microalgae grown under blue wavelengths at 100 μmol photon/m2/sec had the highest dry biomass (1607 pg/cell). The highest percentage of protein was obtained under the blue light (22.83%), carbohydrates under the white light (4.13) and lipids under the red light (35.25%) all these results were observed under the low light intensity (50 μmol photon/m2/sec). The highest cell concentration and growth rate was observed under the low light intensity the largest proportions of which were proteins produced under the blue light. Lipid composition was not affected by light intensity or wavelength

Production and characterization of supercritical CO₂ dried chitosan nanoparticles as novel carrier device

The materials produced by the supercritical CO₂ drying have outstanding properties that allow the incorporation of molecules in their porous structure. In this context, dried chitosan nanoparticles including β-lactoglobulin were obtained. First, the nanoparticles in water suspension were produced by ionotropic gelation incorporating the protein with high loading efficiency. Later, solvent exchange and CO₂ supercritical drying procedures were performed. The physicochemical characteristics and structural properties were determined, demonstrating a stable porous structure in the dried materials and corroborating the presence of the protein after the drying. The CO₂ supercritical dried chitosan nanoparticles can be effectively resuspended in acidic aqueous medium remaining in the nanoscale with minimum effect on the loading parameters. The release of the β-lactoglobulin was highly influenced by the pH, reaching around 40% under acidic conditions in ten hours. The obtained results demonstrate the possibility to apply these chitosan materials as a controlled release material

Fenologia, brotação de gemas e produção de frutos de macieira em resposta à aplicação de cianamida hidrogenada e óleo mineral Phenology, budbreak and apple fruit production by hydrogen cyanamide and mineral oil application

A aplicação de indutores de brotação é uma das principais estratégias de manejo utilizadas para minimizar os problemas da falta de frio em frutíferas de clima temperado. Em razão da influência dos indutores de brotação sobre a resposta produtiva das plantas, a mensuração de seus efeitos ao longo do ciclo produtivo torna-se importante. Assim, o presente trabalho foi desenvolvido no ciclo 2007/2008, em Caçador/SC, objetivando avaliar diferentes combinações de cianamida hidrogenada e óleo mineral sobre a fenologia, brotação de gemas e produção de frutos em macieiras. O delineamento experimental foi em blocos casualizados, com seis repetições compostas de uma planta, seguindo arranjo fatorial (5x2), com cinco níveis de indutor de brotação (1. testemunha; 2. óleo mineral 3,2%; 3. óleo mineral 3,2% + cianamida hidrogenada 0,20%; 4. óleo mineral 3,2% + cianamida hidrogenada 0,39%; 5. óleo mineral 3,2% + cianamida hidrogenada 0,59%) e duas cultivares (Imperial Gala e Fuji Suprema). A aplicação dos indutores de brotação antecipou e reduziu o período de florescimento, aumentando a coincidência de florescimento das cultivares Imperial Gala e Fuji Suprema. Os indutores de brotação uniformizaram e aumentaram a brotação de gemas axilares e terminais, obtendo-se máxima brotação na cultivar Imperial Gala com 0,44% de cianamida hidrogenada e 3,2% de óleo mineral. O aumento da concentração de cianamida hidrogenada revelou a tendência de diminuir a frutificação efetiva. Observaram-se respostas diferenciadas entre tratamentos quanto à produção e à massa média dos frutos, podendo ser atribuídas ao predomínio da produção de frutos em distintas estruturas de frutificação.<br>The budbreak promoters application is one of main management strategies used to decrease the problems of insufficient winter chilling on temperate fruit trees. Because the influence of budbreak promoters on productive behaviour of plants, detecting this effects along of productive season became important. Thus, this study was carried out during 2007/2008 season, in Caçador, Santa Catarina State, Brazil, aiming to evaluate different hydrogen cyanamide and mineral oil combinations on phenology, budbreak and apple fruit production. The experimental design was a randomized block, with six replications, in factorial arrangement (5x2), with five budbreak promoter treatments (1. control; 2. mineral oil 3.2%; 3. mineral oil 3.2% + hydrogen cyanamide 0.20%; 4. mineral oil 3.2% + hydrogen cyanamide 0.39%; 5. mineral oil 3.2% + hydrogen cyanamide 0.59%) and two cultivars (Imperial Gala and Suprema's Fuji). The budbreak promoters application anticipated and reduced the blooming period, increasing the blooming overlap between Imperial Gala and Suprema's Fuji cultivars. The budbreak promoters equalized and increased the budbreak in axillary and terminal buds, with the major budbreak level observed in Imperial Gala cultivar with 0.44% of hydrogen cyanamide and 3.2% of mineral oil treatment. The increase of hydrogen cyanamide concentration showed the tendency to decrease the fruit set. It was observed different treatment responses on production and mean fruit weight, probably to be related to fruit production predominance in different frutification structures

Anales de Edafología y Agrobiología Tomo 35 Número 3-4

Estudio de la materia orgánica del ranker atlántico. II. Análisis químico y espectral del humus, por P. Rodríguez Seoane, T. Carballas y F. Guitián Ojea .-- lnfluencia de P, Mn, Cu, Zn y .Mo en el contenido mineral del Trijolium subterraneum L. (var. Tal/arook). I. Macronutrimentos, por T. González Carreño y H. Carbajal Aced.-- Influencia de P, Mn, Cu, Zn y Mo en el contenido mineral del Trijolium subterraneum L. (var. Tallarook). II. Oligoelementos, por T. González Carreño y H. Carbajal Aced.-- Contribución al estudio de la influencia del 2-4-5-TP y nutrientes foliares en la cinética del crecimiento y desarrollo del limón fino, por A. Ortuño, J. Gómez, J. Rodríguez. A. García Lidón, F. L. Cánovas y J. Millán.-- Efecto de algunos herbicidas sobre un prado permanente, por J. Segura, E. Vieitez y R. Fábregas.-- Parámetros de actividad funcional en el diagnóstico de la deficiencia de hierro y manganeso, por O. Carpena, S. Llorente, A. León y A. Torrecillas.-- Crecimiento y desarrollo del fresón de la Sierra de Francia. ll. Evolución en un ciclo y diferencias con la edad de la planta, por R. Martínez-Carrascoy L. Sánchez de la Puente.-- Materiales amorfos (SiO., Al,O, y Fe,O), en integrados. Andosol-tierra parda oligotrófica de las islas de Tenerife y Gomera, por E. Femández Caldas, M. L. Tejedor Salguero, J. M. Hernánde.z Moreno y O. Cabezas Vieitez.-- Inhibidores fenólicos de la germinación en Erica arborea L., por J. L. Alonso, F. de Landa y E. Vieitez.-- Evolución de la materia orgánica en los suelos pardos de la submeseta meridional, por F. Velasco de Pedro.-- Relaciones suelo-planta, respecto a nitrógeno, en el trigo cultivado en el campo, por G. Fuentes Rodríguez y L. Sánchez de la Puente.-- Rubefacción e hidromorfismo en suelos de terrazas del Guadalquivir. l. Datos geomorfológicos, fisiográficos y morfológicos, por G. Paneque, L. Clemente y W. GarcéS.-- Rubefacción e. hidromorfismo en suelos de terrazas del Guadalquivir. II. Datos físicos químicos y mineralógicos, por L. Clemente, G. Paneque y W. Garcés.-- Nota inicial. Estudio comparado de la fracción arcilla de la facies Madrid y la facies rojiza de Guadalajara, por M. T. Garrcía-Gonzáles y J. L. Moreno Alvarez.-- José María Alhareda. X aniversario de su fallecimiento.- Notas. Constitución de nueva Junta de Gobierno del Patronato «Alonso de Herrera».-- Comisión Permanente de la Junta de Gobierno del Patronato Alonso deHerrera.-- Nombramientos de Consejeros Adjuntos del Patronato Alonso de Herrera.-- Nombramiento del Pro F. Lucena Conde como Director Honorario del Centro de Edafología y Biología Aplicada de Salamanca y del Instituto de Orientación y Asistencia Técnica del Oeste.-- Nombramiento del Director del Centro de Edafología y Biología Aplicada de Salamanca.-- Nombramiento de Director de la Estación Experimental La Mayora.-- Variaciones en la Estación Experimental de Aula Dei.-- Variaciones en la Secretaría del Instituto de Alimentación y Productividad Animal.-- Variaciones en los Centros.-- Consejo Técnico Administrativo de La Mayora.-- Nombramientos de miembros del Consejo Técnico Asesor del Patronato .Alonso de Herrera.-- Nombramientos de Profesores Agregados.-- Curso Internacional de Fertilidad de Suelos y Nutrición Vegetal.-- PrimeraPeer reviewe