48 research outputs found
Hancornia speciosa Gomes: caracterização química, compostos bioativos e atividade antioxidante / Hancornia speciosa Gomes: chemical characterization, bioactive compounds and antioxidant activity
A Hancornia speciosa Gomes é uma árvore frutífera que está presente na zona de transição da Floresta Amazônica para o Cerrado e apresenta uma grande importância sócio- cultural. O objetivo deste projeto foi analisar as propriedades físico-químicas e seus compostos bioativas presentes na entrecasca da mangabeira (Hancornia speciosa Gomes). As análises fisíco quimicas foram feitas seguindo os procedimentos descritos no livro de métodos do Instituto Adolf Lutz e seguindo o método AOAC. Para determinação dos compostos bioativos, as análises de compostos fenólicos, submeteu-se a amostra à extração alcoólica e aquosa. As análises de antocianinas e flavonoides foram realizadas por meio da extração com etanol e HCl 1,5 N. Foi determinado a quantidade de licopeno e betacaroteno presentes na amostra por meio da extração com cetona-hexano. A atividade antioxidante total foi determinada pelo método de captura de radicais DPPH. As análises foram realizadas com o auxílio da espectrofotometria em triplicata, com exceção da quantificação do teor de ácido ascórbico determinado pelo método Balentine com volumetria de oxirredução, em duplicata. Os resultados das análises determinaram uma acidez titulável total de 3,3967%; acidez total de 2,19%; pH de 3,87; ácido ascórbico de 50,7076 mg/ 100g; cinzas de 0,13 mg/100g; proteínas de 0,51mg/100g; sólidos solúveis totais de 0,1 0 Brix; relação SST/ATT de 0,041 e fibra bruta de 38,01%. A entrecasca analisada demonstrou altos valores na determinação de compostos fenólicos com 717,15 ± 7,5 e 700,48 ± 7,57 mg GAE/100g, para os extratos aquosos e alcoólicos, respectivamente. A atividade antioxidante também apresentou teor elevado tendo 0,49 g fruta/ g DPPH. Os teores de antocianinas mostraram-se um pouco cima do esperado e os valores referentes aos flavonoides foram inconclusivos. O valor encontrado de licopeno foi superior ao obtido no ensaio do betacaroteno, podendo justificar a presença de cor vermelha intensa na maioria dos extratos obtidos com a entrecasca. Por fim, o teor obtido para o ácido ascórbico foi de 51,8546 ± 0,12 mg/100 g. Deste modo, os resultados da caracterização físico-química apresentaram valores centesimais importantes para a caracterização da entrecasca, diante de seu uso e importância medicinal. Além disso, mostrou boas características funcionais para ser empregada no consumo humano e ampliar os estudos nessa espécie
ESTUDIO DE PREFACTIBILIDAD PARA LA INSTALACION DE UNA PLANTA PRODUCTORA DE BIOPLASTICO PHB
Synergistic effect of divalent cations in improving technological properties of cross-linked alginate beads
Gelling solution parameters are some of the most important variables in ionotropic gelation and consequently influence the technological characteristics of the product. To date, only a few studies have focused on the simultaneous use of multiple cations as gelling agents. With the aim to deeply explore this possibility, in this research we investigated the effect of two divalent cations (Ca2+ and Zn2+) on alginate beads formation and properties. Alginate beads containing prednisolone (P) as model drug were prepared by prilling technique. The main critical variables of the ionotropic gelation process i.e. composition of the aqueous feed solutions (sodium alginate and prednisolone concentration) and cross-linking conditions (Ca2+, Zn2+ or Ca2+ + Zn2+), were studied. The obtained beads were characterized and their in vitro release performances were assessed in conditions simulating the gastrointestinal environment. Results evidenced a synergistic effect of the two cations, affecting positively both the encapsulation efficiency and the ability of the alginate polymeric matrix to control the drug release. A Ca2+/Zn2+ ratio of 4:1, in fact, exploited the Ca2+ ability of establish quicker electrostatic interactions with guluronic groups of alginate and the Zn2+ ability to establish covalent-like bonds with carboxylate groups of both guluronic and mannuronic moieties of alginate
Primera cita de Megastigmus zebrinus Grissell de Argentina (Hymenoptera: Torymidae) asociado a agallas de Leptocybe invasa (Hymenoptera: Eulophidae) = First record of Megastigmus zebrinus Grissell from Argentina (Hymenoptera: Torymidae) associated with galls of Leptocybe invasa (Hymenoptera: Eulophidae)
Se cita por primera vez de Argentina la presencia de Megastigmus zebrinus Grissell (Hymenoptera: Torymidae) asociada a agallas de Eucalyptus camaldulensis Dehnhardt (Myrtaceae) producidas por Leptocybe invasa Fisher & LaSalle (Hymenoptera: Eulophidae) de la provincia de Buenos Aires. Megastimus zebrinus fue hallada en Australia, su país de origen, y en Sudáfrica.Megastigmus zebrinus Grissell (Hymenoptera: Torymidae) is reported for the first time from Argentina, associated with galls of Eucalyptus camaldulensis Dehnhardt (Myrtaceae) induced by the gall-forming wasp, Leptocybe invasa Fisher & LaSalle (Hymenoptera: Eulophidae), in Buenos Aires. Megastimus zebrinus was previously found in Australia, its home country, and South Africa.Instituto de Microbiología y Zoología AgrícolaFil: Hernandez, Carmen Marcela. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Microbiología y Zoología Agrícola. Insectario de Investigaciones Lucha Biológica; ArgentinaFil: Aquino, Daniel A. Universidad Nacional de la Plata. Facultad de Ciencias Naturales y Museo. División Entomología; ArgentinaFil: Cuello, Eliana Marina. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Microbiología y Zoología Agrícola. Insectario de Investigaciones Lucha Biológica; ArgentinaFil: Andorno, Andrea Veronica. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Microbiología y Zoología Agrícola. Insectario de Investigaciones Lucha Biológica; ArgentinaFil: Botto, Eduardo Norberto. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Microbiología y Zoología Agrícola. Insectario de Investigaciones Lucha Biológica; Argentin
Exportación a costa rica con financiamiento a carta de crédito
Seminario: el crédito comercial y su importancia en los negocios internacionale
A vision-based closed spirulina (a. platensis) cultivation system with growth monitoring using artificial neural network
This paper presents the development of a closed algal cultivation system that automatically monitors and controls significant bio-environmental parameters to optimize the growth of the microalgae Spirulina platensis, which is normally used as fish feeds. The system is composed of three major parts: the detection system, which monitors the pH level, temperature and dissolved oxygen (DO) level; the correction system, which maintains the important parameters for optimum growth of the culture, 29 to 32 degree Celsius for temperature and 8.5 to 11 for pH; and the vision system which measures the cell density of the culture using an artificial neural network (ANN) model. The ANN model measures the cell density of the culture based on the RGB and lux values from the vision. The system then gives out a notification when the culture has reached its mature phase and is ready for harvesting. Based on the results of the experimental setups performed, the culture system was able to reach its matured phase on its 5th day for controlled and on the 7th day for uncontrolled. Furthermore, based on the regression analysis performed, the growth coefficient for the controlled set-up is 0.0519 and 0.0372 for the uncontrolled setup; the growth of Spirulina platensis has increased by 39.52% when the culture parameters are controlled. © 2018 IEEE
Long-term apoptosis-related protein expression in the diabetic mouse ovary.
Emerging evidence has shown that oocytes from diabetic ovaries exhibit delayed maturation, mitochondrial dysfunction and meiotic defects, which are related increased apoptosis. The main objective of the present study was to analyze the apoptosis pathways activated during follicular loss at multiple time points in a diabetic mouse model. Twenty BALB/c mice were used in this study, and diabetes mellitus was induced by streptozotocin injection. Three diabetic and two control animals were sacrificed on days 15, 20, 70 and 80 posttreatment. The ovaries were then removed; one was used for follicular counting, TUNEL, immunohistochemistry and immunofluorescence, while the other was used for Western blot analysis. The proteins studied were BAX, BCL2, t-BID, FAS, FASL, active caspase 8, active caspase 9 and active caspase 3. Follicular apoptosis decreased over time, with the highest values observed at 15 days posttreatment. Granulosa cells were positive for active caspase 3, which showed constant expression levels at all time points. FAS, FASL, t-BID and active caspase 8 showed strong cytoplasmic immunostaining in the oocytes and granulosa cells of the diabetic mice, with significant increases observed at 15, 20 and 70 days posttreatment. BAX expression was slightly higher in the diabetic mouse ovaries than in the control ovaries at 15, 20 and 70 days posttreatment, whereas the highest active caspase 9 expression was at observed 20 days posttreatment. Low BCL2 protein levels were detected in the diabetic mouse ovaries at all time points. This study describes for the first time the behavior of apoptosis-related proteins in the diabetic mouse ovary and shows not only that the FAS/FASL pathway contributes to follicular loss but also that antral follicles are the most affected
Ig-like transcript 7, but not bone marrow stromal cell antigen 2 (also known as HM1.24, tetherin, or CD317), modulates plasmacytoid dendritic cell function in primary human blood leukocytes
The immunoglobulin-like transcript (ILT) 7 is a surface molecule selectively expressed by human plasmacytoid dendritic cells (pDCs). ILT7 cross-linking suppresses pDC activation and type I interferon (IFN-I) secretion following Toll-like receptors (TLR)7/9 engagement. The bone marrow stromal cell antigen 2 (BST2, aka HM1.24, tetherin or CD317) is expressed by different cell types upon exposure to IFN-I and is a natural ligand for ILT7. Here we show that ILT7 expression decreased spontaneously in pDCs upon in vitro culture, which correlates with pDC differentiation measured as increased side scatter properties and CCR7 expression. TLR7/9 Ligands , as well as HIV, induced BST2 upregulation on all tested cell types except T cells, which required TCR stimulation to respond to TLR9L-induced IFN-I. IFN-γ, IL-4, IL-10 and TNF-α had only marginal effects on BST2 expression in blood leukocytes compared to TLR9L. Pre-incubation with ILT7-crosslinking Ab inhibited IFN-I production in PBMCs treated with TLR7/9L or HIV, whereas BST2 blockade did not affect IFN-I responses even when BST2 upregulation was further boosted with TCR agonists or immunoregulatory cytokines. Our data indicate that BST2-mediated ILT7 cross-linking may act as a homeostatic regulatory mechanism on immature circulating pDC, rather than a negative feedback for activated mature pDCs which have downregulated ILT7