Estudo das características físico-químicas e biológicas pela adesão de osteoblastos em superfícies de titânio modificadas pela nitretação em plasma

SILVA, J. S. P. Estudo das características físico-químicas e biológicas pela adesão de osteoblastos em superfícies de titânio modificadas pela nitretação em plasma. 2008. 119 f. Tese (Doutorado) - Faculdade de Medicina, Universidade de São Paulo. São Paulo, 2008.

Uso de diferentes agentes ligantes no desenvolvimento de barra de cereal salgada adicionada de chia (Salvia hispânica L.)

The objective of this study was to evaluate different binders when preparing salt cereal bars and to characterize them as physical, physico-chemical and sensory parameters. Four formulations of different cereal bars using binders have been developed. The evaluated binders were collagen, guar gum, xanthan gum and psyllium. The developed cereal bars were evaluated according to their physical characteristics (color and texture), physicochemical (pH, moisture, ash, protein, lipids, Aw, crude fiber) beyond their calorie, fatty acid composition and concentration of the main minerals. Among the four binding agents evaluated, psyllium stood out due to its physicochemical characteristics. A cereal bar high in protein and fiber; low in carbohydrates and water activity. The binding agent guar gum and xanthan showed characteristics similar to psyllium, especially regarding to fiber content. Collagen as binder gave the final product a high level in protein and lipid. The color and texture analyzes showed that the salt cereal bars had the color and crispness characteristics for this type of product. Regarding to the composition in the fatty acid, the developed bars offer a good supply of essential fatty acids to the human body. The same was observed regarding to mineral contents. Sensory, salt cereal bars made with chia showed good acceptability, highlighting the elaborate bar with psyllium binder. Different binders demonstrated technological efficiency in the preparation of salt cereal bars. The binder psyllium agent over others showed better physical-chemical and sensory characteristics. However, in general the product has healthy and nutritional characteristics it may be indicated for a protein diet with high fiber content and free sugars.

The physico-chemistry of the northern waters of Lake Victoria

In this paper, we try to briefly review the current physico-chemical data pertaining to Northern Lake Victoria which could eventually be used to explain the following:- (a) whether there bas been a change of the dissolved organic nutrient cencentrations when compared with the pre-perch period, (b) the specific point sources of the influent nutrients and other chemicals and how they correlate with changes in algal productivity, and (c) whether the data can contribute to the validation of the Lake Victoria ecological model developed by Jorgensen at al. (1982).

Efeitos dos fatores ambientais na comunidade de macrófitas em pequenos cursos lóticos perenes subtropicais

Neste estudo foi investigado como a distribuição das espécies e a produção de biomassa de macrófitas aquáticas são influenciadas pelas condições físico-químicas do ambiente. Também foi avaliado como uma espécie com maior potencial competitivo pode interferir na diversidade de espécies da comunidade macrofítica. Para tanto, em cada um dos três arroios, foram dispostos seis transecções, perpendiculares à margem. Em cada transecção foram demarcadas três unidades amostrais de 1m², nas quais foram registrados os parâmetros fitossociológicos cobertura e frequência relativas e valor de importância. A diversidade de espécies foi estimada pelo índice de Shannon, utilizando os valores de cobertura de espécies. Para determinar a biomassa das macrófitas aquáticas foram usados quadrats de 0,25m², alocados dentro da unidade amostral de 1m² usadas para quantificar os dados fitossociológicos, nos mesmos pontos onde foi feito o levantamento de cobertura da vegetação. Utilizamos como variáveis preditoras a velocidade da corrente, radiação solar incidente, coeficiente de sombreamento, vegetação ripária arbórea adjacente, nitrogênio orgânico dissolvido, carbono orgânico dissolvido e condutividade elétrica. Foram registradas 32 espécies de macrófitas aquáticas, distribuídas em 19 famílias e 28 gêneros. Conforme Análise de Correspondência Canônica (CCA), as espécies com maiores valores de biomassa foram relacionadas a unidades amostrais com alta incidência luminosa. As unidades amostrais com dominância de Pistia stratiotes apresentaram menor diversidade de espécies indicando que esta espécie, quando encontra condições que permitam sua proliferação, pode excluir espécies de menor potencial competitivo. De acordo com GLM (Generalized Linear Model), a ausência de vegetação ripária ou presente em apenas uma das margens e baixas velocidades de corrente configura-se em condições favoráveis ao estabelecimento e desenvolvimento de macrófitas aquáticas, possibilitando produção maiores valores de biomassa.

Bioecology and conservation of Duck Mussel Species (Anodonta anatina L., 1758) in Northeastern Portugal

Freshwater mussel (Mollusca, Bivalvia, Unionoida) populations are one of the most endangered faunistic groups. Mussels play an important role in the functioning of aquatic ecosystems, because they are responsible for the filtration and purification of water. They have a complex life cycle, with a parasitic larvae and usually limited host fish species. The real status of these populations is still poorly understood worldwide. The objectives of the present work were the study of bioecology of duck mussel (Anodonta anatina L.) populations of Tua Basin (NE Portugal). It was made the characterization of the ecological status of Rabaçal, Tuela and Tua Rivers, selecting 15 sampling sites, equally distributed by the three rivers. Samplings were made in the winter of 2016, and several physico-chemical water parameters measured and two habitat quality indexes calculated (GQC and QBR indexes). Benthic macroinvertebrate communities were sampled based on the protocols established by the Water Framework Directive. Host fish populations for duck mussel were determined in laboratorial conditions, testing several native and exotic fish species. The results showed that several water quality variables (e.g. dissolved oxygen, conductivity, pH, total dissolved solids, and nutrients) can be used for the classification of river typology. Other responsive metrics were also determined to identify environmental degradation. For instances, hydromorphological conditions (GQC and QBR indexes) and biota related metrics (e.g. composition, distribution, abundance, diversity of invertebrate communities) contributed to the evaluation of the ecological integrity. The upper zones of Rabaçal and Tuela rivers were classified with excellent and good ecological integrity, while less quality was found in downstream zones. The host fish tests showed that only native species are effective hosts, essential for the conservation purposes of this mussel species. Threats, like pollution, sedimentation and river regularization (3 big dams are in construction or in filling phase), are the main cause of habitat loss for native mussel and fish populations in the future. Rehabilitation and mitigation measures are essential for these lotic ecosystems in order to preserve the prioritary habitats and the native species heavily threatened.

Résultats de la mise en oeuvre des réseaux REPHY et SRN – Zones côtières de la Manche orientale et de la baie sud de la Mer du Nord – Bilan de l’année 2015

The coastal zone of the Nord – Pas de Calais / Picardie showed dysfonctioning patterns of the ecosystem considered to be link to human activities along shores. These results in regular massive development of species, such as the phytoplanktonic seaweed, Phaeocystis sp. which life cycle was partly linked to nutrients availability and consequently to anthropogenic inputs. As part of the evaluation of the influence of continental inputs on the marine environment (nitrates, phosphates,…) and on potential eutrophication processes, of the estimation of the efficiency of the sewage treatments plants in the possible elimination of dumpings and in order to establish a long-term survey to follow up the change in coastal waters quality, the regional nutrients monitoring network was implemented by Ifremer in collaboration with the Agence de l'Eau Artois-Picardie in 1992 in order to complete the REPHY (Phytoplankton and Phycotoxins) monitoring programme. This study reports the main results for the year 2015 in terms of temporal change of the main physico-chemical and biological parameters characteristic of water masses sampled along three transects offshore Dunkerque, Boulogne-sur-Mer and the Bay of Somme.

Changes in the annual harmful algal blooms of Alexandrium minutum : effects of environmental conditions and drainage basin inputs in the Rance estuary (Brittany, France)

Time series of physico-chemical data and concentrations (cell L-1) of the toxic dinoflagellate Alexandrium minutum collected in the Rance macrotidal estuary (Brittany, France) were analyzed to understand the physico-chemical processes of the estuary and their relation to changes in bloom development from 1996 to 2009. The construction of the tidal power plant in the north and the presence of a lock in the south have greatly altered hydrodynamics, blocking the zone of maximum turbidity upstream, in the narrowest part of the estuary. Alexandrium minutum occurs in the middle part of the estuary. Most physical and chemical parameters of the Rance estuary are similar to those observed elsewhere in Brittany with water temperatures between 15–18 °C, slightly lowered salinities (31.8–33.1 PSU), low river flow rates upstream and significant solar radiation (8 h day-1). A notable exception is phosphate input from the drainage basin which seems to limit bloom development: in recent years, bloom decline can be significantly correlated with the decrease in phosphate input. On the other hand, the chemical processes occurring in the freshwater-saltwater interface do not seem to have an influence on these occurrences. The other hypotheses for bloom declines are discussed, including the prevalence of parasitism, but remain to be verified in further studies.

Caracterização físico-química de complexo de inclusão entre hidroximetilnitrofurazona e hidroxipropil-beta-ciclodextrina

Hydroxymethylnitrofurazone (NFOH) is a prodrug that is active against Trypanosoma cruzi. It however presents low solubility and high toxicity. Hydroxypropyl-beta-cyclodextrin (HP-beta-CD) can be used as a drug-delivery system for NFOH modifying its physico-chemical properties. The aim of this work is to characterize the inclusion complex between NFOH and HP-beta-CD. The rate of NFOH release decreases after complexation and thermodynamic parameters from the solubility isotherm studies revealed that a stable complex is formed (deltaGº= 1.7 kJ/mol). This study focuses on the physico-chemical characterization of a drug-delivery formulation that comes out as a potentially new therapeutic option for Chagas disease treatment.

Extended use of gamma irradiation in wild mushrooms conservation: validation of 2 kGy dose to preserve their chemical characteristics

Irradiation is recognized by international organizations as a conservation technology, and its application to wild mushrooms has been tested in some species. Our research group evaluated the effectiveness of gamma irradiation to conserve different samples of highly appreciated species, particularly, Lactarius deliciosus, Macrolepiota procera, Boletus edulis and Hydnum repandum. From those results and considering also international recommendations on this subject, the 2 kGy dose was chosen for further studies. Therefore, the application of gamma irradiation at 2 kGy dose was extended to Boletus pinophilus Pilát & Dermek and Clitocybe subconnexa Murrill to validate the proposed technology. Considering the obtained results, some of the analysed chemical parameters (specially sugars and fatty acids), as well as the antioxidant activity, showed significant changes after irradiation treatment, particularly in B. pinophillus, probably due to its higher water content. Nevertheless, the obtained differences did not seem to be sufficient to change the organoleptic characteristics of these mushrooms. Furthermore, the antioxidant activity was generally higher in irradiated samples. In conclusion, the detected chemical changes might be considered as acceptable, when considering the high advantages of gamma irradiation at decontamination and/or disinfestation level.

Desenvolvimento de bioblendas poliméricas a partir de gelatina bovina e de tilápia com amido de milho

The natural raw materials acquired special importance beside the mineral raw materials with the need for using alternative sources to oil, because they can be used to produce biopolymers. Gelatin, produced from the denaturation of collagen, and starch, an abundant polysaccharide in various plants, are examples of biopolymers which have several technological applications, especially in films. The objective of this work is to produce polymeric bioblends with gelatin and corn starch using two types of gelatin: commercial bovine gelatin and gelatin produced from mechanically separated flesh of tilapia (Oreochromis niloticus). For the extraction of tilapia gelatin 3 distinct pretreatments, followed by extraction in distilled water under heating were performed. The properties of gelatin extracted were similar to bovine gelatin, and the differences can be explained by the difference in extraction processes and sources. Blends of commercial gelatin and starch were produced in an internal mixer from a Haake torque rheometer, to study the behavior of the gelatin mixture with starch, thus, the same compositions were processed by twin screw extrusion, to define the mixing parameters. Subsequently, the extrusion of blends of tilapia gelatin and corn starch was carried out in the same twin screw extruder. The physico-chemical, rheological and morphological properties of the blends with thermoplastic starch and gelatin were studied. It was found that various properties vary linearly with increasing concentration of the components. The blends produced are immiscible, and among the two gelatins, tilapia gelatin showed a better interfacial adhesion with the corn starch. Regarding the morphology, gelatins formed the dispersed phase in all compositions studied, even in compositions rich in starch. Can be concluded that the procedure for tilapia gelatin extraction is feasible and advantageous, and the increasing in its scale to a reactor of 30 liters is possible, with a satisfactory yield. The bioblends of bovine gelatin/corn starch and tilapia gelatin/corn starch were successfully produced, and the processing conditions were appropriate

Chemical and aromatic characteristics of Brazilian tropical wines.

Traditional winegrowing areas are located in temperate climate zones and allow to produce grapes only once per year. Tropical wines have been elaborated in India, Thailand, Venezuela and Brazil and present another kind of viticulture, as compared with countries located in temperate climate zones. Northeast of Brazil started wine production twenty six years ago. This region vines can produce two or three crops per year, depending of the cycle of different cultivars. Harvests can be scaled throughout the year, mainly between May and December, corresponding to the dry season. Red, white, rosé and sparkling wines are being elaborated in the region. The objective of this work was to determine the physico-chemical and aromatic characteristics of some tropical wines elaborated in Northeast of Brazil, with grapes harvested in November 2008. Wines were elaborated using traditional method with control of the alcoholic and malolactic fermentation temperatures, at 25 and 18ºC for red wines, respectively, and at 18ºC for alcoholic fermentation of the white wines. After stabilization and bottling and wines were analyzed to determine physico-chemical characteristics, like alcohol degree, pH, total and volatile acidities, dry extract, sulfur dioxide, total anthocyanin and total phenol index. Aromatic profile was determined by gas chromatography, while 19 esters and 6 superior alcohols were identified. Wines presented different chemical and aromatic characteristics according to different grape cultivars.

Removal Of Glyphosate Herbicide From Water Using Biopolymer Membranes.

Enormous amounts of pesticides are manufactured and used worldwide, some of which reach soils and aquatic systems. Glyphosate is a non-selective herbicide that is effective against all types of weeds and has been used for many years. It can therefore be found as a contaminant in water, and procedures are required for its removal. This work investigates the use of biopolymeric membranes prepared with chitosan (CS), alginate (AG), and a chitosan/alginate combination (CS/AG) for the adsorption of glyphosate present in water samples. The adsorption of glyphosate by the different membranes was investigated using the pseudo-first order and pseudo-second order kinetic models, as well as the Langmuir and Freundlich isotherm models. The membranes were characterized regarding membrane solubility, swelling, mechanical, chemical and morphological properties. The results of kinetics experiments showed that adsorption equilibrium was reached within 4 h and that the CS membrane presented the best adsorption (10.88 mg of glyphosate/g of membrane), followed by the CS/AG bilayer (8.70 mg of glyphosate/g of membrane). The AG membrane did not show any adsorption capacity for this herbicide. The pseudo-second order model provided good fits to the glyphosate adsorption data on CS and CS/AG membranes, with high correlation coefficient values. Glyphosate adsorption by the membranes could be fitted by the Freundlich isotherm model. There was a high affinity between glyphosate and the CS membrane and moderate affinity in the case of the CS/AG membrane. Physico-chemical characterization of the membranes showed low values of solubility in water, indicating that the membranes are stable and not soluble in water. The SEM and AFM analysis showed evidence of the presence of glyphosate on CS membranes and on chitosan face on CS/AG membranes. The results showed that the glyphosate herbicide can be adsorbed by chitosan membranes and the proposed membrane-based methodology was successfully used to treat a water sample contaminated with glyphosate. Biopolymer membranes therefore potentially offer a versatile method to eliminate agricultural chemicals from water supplies.

Properties Of Bologna-type Sausages With Pork Back-fat Replaced With Pork Skin And Amorphous Cellulose.

Bologna-type sausages were produced with 50% of their pork back-fat content replaced with gels elaborated with different ratios of pork skin, water, and amorphous cellulose (1:1:0, 1:1:0.1, 1:1:0.2, 1:1:0.3, and 1:1:0.4). The impact of such replacement on the physico-chemical characteristics and the consumer sensory profiling was evaluated. The modified treatments had 42% less fat, 18% more protein, and 8% more moisture than the control group. Treatments with amorphous cellulose had a lower cooking loss and higher emulsion stability. High amorphous cellulose content (1:1:0.3 and 1:1:0.4) increased hardness, gumminess, and chewiness. The gel formulated with the ratio of 1:1:0.2 (pork skin: water: amorphous cellulose gel) provided a sensory sensation similar to that provided by fat and allowed products of good acceptance to be obtained. Therefore, a combination of pork skin and amorphous cellulose is useful in improving technological quality and producing healthier and sensory acceptable bologna-type sausages.

Combining Xanthan And Chitosan Membranes To Multipotent Mesenchymal Stromal Cells As Bioactive Dressings For Dermo-epidermal Wounds.

The association between tridimensional scaffolds to cells of interest has provided excellent perspectives for obtaining viable complex tissues in vitro, such as skin, resulting in impressive advances in the field of tissue engineering applied to regenerative therapies. The use of multipotent mesenchymal stromal cells in the treatment of dermo-epidermal wounds is particularly promising due to several relevant properties of these cells, such as high capacity of proliferation in culture, potential of differentiation in multiple skin cell types, important paracrine and immunomodulatory effects, among others. Membranes of chitosan complexed with xanthan may be potentially useful as scaffolds for multipotent mesenchymal stromal cells, given that they present suitable physico-chemical characteristics and have adequate tridimensional structure for the adhesion, growth, and maintenance of cell function. Therefore, the purpose of this work was to assess the applicability of bioactive dressings associating dense and porous chitosan-xanthan membranes to multipotent mesenchymal stromal cells for the treatment of skin wounds. The membranes showed to be non-mutagenic and allowed efficient adhesion and proliferation of the mesenchymal stromal cells in vitro. In vivo assays performed with mesenchymal stromal cells grown on the surface of the dense membranes showed acceleration of wound healing in Wistar rats, thus indicating that the use of this cell-scaffold association for tissue engineering purposes is feasible and attractive.

EFEITO DA ASSOCIAÇÃO DE PECTINASE, INVERTASE E GLICOSE ISOMERASE NA QUALIDADE DO SUCO DE BANANA

The association of 0,03 % v/w pectinase (Clarex), 0,6 % v/w invertase (Invertase-S) and 0,5 % w/w glucose isomerase (Taka-sweet) in industrialized banana (Musa cavendishii) pulp, under conditions of hydrolysis 40oC, 15 minutes, was observed and compared to other three enzymatic treatements: 0,03 % v/w pectinase (Clarex); 0,03 % v/w pectinase (Clarex) associated to 0,6 % v/w invertase (Invertase-S); and 0,03 % v/w pectinase (Sigma) associated to 0,03 % cellulase (Sigma) to determine the quality using a group of physical, physico-chemical, chemical, microbiological and sensory properties of the banana juices obtained. These properties had not differ significantly in function of pectinases and celulase employed. The addition of invertase had increased sweetness and decreased viscosity in juice. On the other side, the addition of glucose isomerase in inverted juice was not able in increasing significantly fructose content.