Production and characterization of ZrCN-Ag coatings deposited by mganetron sputtering

Tese de Doutoramento (Programa doutoral em Engenharia de Materiais)

Biotechnological valorization of waste cooking oils: lipase and microbial lipids production by Yarrowia lipolytica

[Excerpt] Waste cooking oils (WCO) generated from vegetable oils used at high temperatures in food frying, cause environmental problems and must be reutilized. New strategies to valorize these wastes are attracting a great scientific interest due to the important advantages offered from an economic and environmental point of view. A microbial platform can be established to convert low-value hydrophobic substrates, such as waste cooking oils, to microbial lipids (single cell oil, SCO) and other value-added bioproducts, such as lipase. (...)

Biosynthesis, detection and toxicology of ochratoxins - optimisation of production

Ochratoxin A (OTA) is a very well known mycotoxin found in several food commodities for which maximum limits are being discussed in EC in other to produce appropriate regulations. OTA is one of several ochratoxins produced by Aspergillus and Penicillium species. All the compounds in this group have a molecular structure very similar to OTA and some were already isolated from natural substrates. Several of these compounds such as ochratoxin , methyl and ethyl ester of ochratoxin A, 4-R and S-hydroxyochratoxin A, 10-hydroxyochratoxin A and ochratoxin A open lactone are commercially unavailable. However, they can be easily synthesized through OTA modification. With the main objective of its application on further research works, OTA production, isolation and purification has been optimised from an A. alliaceus strain grown on wheat medium. Synthesis and purification of some OTA derivatives has been achieved and an HPLC method for their detection was optimised. Data about their production by several species of Aspergillus will be presented. The toxicological properties of ochratoxins are still not very clear and a future EC safety limit for OTA will depend on e.g., a better clarification of its carcinogenity. Could OTA derivatives play a role here?

Production of medium-chain fatty acids and higher alcohols by a synthetic co-culture grown on carbon monoxide or syngas

Synthesis gas, a mixture of CO, H2, and CO2, is a promising renewable feedstock for bio-based production of organic chemicals. Production of medium-chain fatty acids can be performed via chain elongation, utilizing acetate and ethanol as main substrates. Acetate and ethanol are main products of syngas fermentation by acetogens. Therefore, syngas can be indirectly used as a substrate for the chain elongation process.

Biocatalysis in micellar systems

[Excert] Biocatalysis and biotransformations are environmentally friendly, and allow the development of sustainable production processes on a large scale. Thus, these processes are becoming important alternatives to conventional chemistry in the drug, biochemical, and emerging biorenewable energy industries. Biocatalysts are required to function under non-conventional conditions, such as in organic solvents, being competitive in terms of cost and efficiency. In fact, the technological utility of enzymes can be enhanced greatly by using them in the presence of organic solvents, rather than in their natural aqueous reaction media. Multiphase systems are more complex but offer a new field of possibilities. The presence of hydrophobic solvents in biocatalysis allows the conversion of poorly water soluble substrates more efficiently. The accessibility of hydrophobic substrates to enzymes or whole cells presents an interesting challenge for researchers and technologists. In this context, microemulsions are a promising tool in enzyme technology. This chapter presents an overview of the characterization of biphasic and microemulsion systems and their applications in biotransformation processes (...).

The state of art of biological processes in paternal care

This review of the state of art aimed to present the most recent data on neuronal, neurochemical, hormonal and genetic bases of paternal care using MEDLINE and PsycInfo databases (1970-2013). An integrated model of biological substrates that assist men in the transition to fatherhood is presented. Guided by a genetic background, hypothalamic-midbrain-limbic-paralimbic-cortical circuits were found to be activated in fathers when infant stimuli are presented. A set of specifi c neuropeptides and steroid hormones are produced and seem to be related to brain activation, potentiating the paternal phenotype. Together, genetic, brain and hormonal processes suggest the existence of biological bases of paternal care in humans, activated and enhanced by infant stimuli and responsive to variations in the father-infant relationship.

Acabamentos funcionais têxteis aplicados por estamparia digital em substratos têxteis ativados por plasma

Tese de Doutoramento em Engenharia Têxtil

Electroquímica de sustancias de interés en los sistemas agroalimentario y de sanidad animal. Desarrollo de biosensores electroquímicos. Aplicaciones analíticas.Electrochemistry of substances of interest in agroalimentary and animal health systems. Development of electrochemical biosensors. Analytical applications.

Se estudiarán los mecanismos de reacción electroquímica de las micotoxinas (metabolitos tóxicos generados por hongos) citrinina (CIT), patulina (PAT) y moniliformina (MON), de los antioxidantes naturales alfa, beta, gama y delta tocoferoles, de los flavonoides fisetina (FIS), morina (MOR), luteolina (LUT), rutina (RUT), buteina (BUT), naringenina (NAR) y miricetina (MIR) y de las hormonas esteroides estradiol (EDIOL), estrona (EONA) y estriol (ETRIOL). Por otra parte, se implementarán técnicas electroanalíticas para la detección y cuantificación de estos sustratos en muestras de matrices naturales que los contengan. Se realizará el diseño y caracterización de biosensores enzimáticos a partir de peroxidasas y/o fosfatasa alcalina para la determinación de la micotoxina CIT y de los flavonoides y, por otro, de inmunosensores para las micotoxinas ocratoxina A (OTA) y PAT y hormonas. Para el anclaje de enzimas y/o anticuerpos, se estudiarán las propiedades de electrodos modificados por monocapas autoensambladas, nanotubos de carbono y partículas magnéticas. Se usarán las técnicas de voltamperometría cíclica, de onda cuadrada y de redisolución con acumulación adsortiva, espectroscopías de impedancia electroquímica, electrólisis a potencial controlado, uv-vis e IR, microbalanza de cristal de cuarzo y microscopías de alta resolución (SEM, TEM, AFM). La importancia de este proyecto apunta a la obtención de nuevos datos electroquímicos de los sustratos indicados y conocimientos relacionados con la aplicación de electrodos modificados en la preparación de biosensores y en el desarrollo de técnicas alternativas para la determinación de los analitos mencionados precedentemente. Electrochemical reaction mechanisms of mycotoxins (toxic metabolites generated by fungi) citrinin (CIT), Patulin (PAT) and moniliformin (MON), natural antioxidants alpha, beta, gamma and delta tocopherols, flavonoids fisetin (FIS), morin (MOR), luteolin (LUT), rutin (RUT), butein (BUT), naringenin (NAR), miricetin (MIR) and steroid hormones estradiol (EDIOL), estrone (EONA) and estriole (ETRIOL) will be explored. On the other hand, electroanalytical techniques for the detection and quantification of these substrates in samples of natural matrices will be implemented. The design and characterization of enzymatic biosensors from peroxidases and/or from alkaline phosphatase for the determination of CIT and flavonoids, and also of inmunosensors for ochratoxin A (OTA) and PAT and hormones will be performed. For the anchor of enzymes and/or antibody, properties of electrodes modified by self assembled monolayers, carbon nanotubes and magnetic particles will be explored. Cyclic, square wave and adsorptive stripping voltammetries, electrochemical impedance spectroscopy, controlled potential electrolysis, uv-vis and IR, quartz crystal microbalance and high-resolution microcopies (SEM, TEM, AFM) will be used. The importance of this project is aimed at obtaining new electrochemical data for the indicated substrates and knowledge on the application of modified electrodes in preparation of biosensors and in the development of alternative techniques for the determination of the above-mentioned analytes.

Human Tissue Kallikrein Activity in Angiographically Documented Chronic Stable Coronary Artery Disease

AbstractBackground:Human tissue kallikrein (hK1) is a key enzyme in the kallikrein–kinin system (KKS). hK1-specific amidase activity is reduced in urine samples from hypertensive and heart failure (HF) patients. The pathophysiologic role of hK1 in coronary artery disease (CAD) remains unclear.Objective:To evaluate hK1-specific amidase activity in the urine of CAD patientsMethods:Sixty-five individuals (18–75 years) who underwent cardiac catheterism (CATH) were included. Random midstream urine samples were collected immediately before CATH. Patients were classified in two groups according to the presence of coronary lesions: CAD (43 patients) and non-CAD (22 patients). hK1 amidase activity was estimated using the chromogenic substrate D-Val-Leu-Arg-Nan. Creatinine was determined using Jaffé’s method. Urinary hK1-specific amidase activity was expressed as µM/(min · mg creatinine) to correct for differences in urine flow rates.Results:Urinary hK1-specific amidase activity levels were similar between CAD [0.146 µM/(min ·mg creatinine)] and non-CAD [0.189 µM/(min . mg creatinine)] patients (p = 0.803) and remained similar to values previously reported for hypertensive patients [0.210 µM/(min . mg creatinine)] and HF patients [0.104 µM/(min . mg creatinine)]. CAD severity and hypertension were not observed to significantly affect urinary hK1-specific amidase activity.Conclusion:CAD patients had low levels of urinary hK1-specific amidase activity, suggesting that renal KKS activity may be reduced in patients with this disease.

Ecologia de Xylocopa (Neoxylocopa) cearensis (Hymenoptera, Anthophoridae) nas dunas litorâneas de Abaeté, Salvador, Bahia

The study was carried out in a 8.2 ha area in an environmental protection area of tropical sea coastal sand dune with "restinga" vegetation in Salvador, Bahia, northeastern Brazil. A total of 1760 bees of Xylocopa (Neoxylocopa) cearensis Ducke, 1910 were netted during the whole year on flowers of 43 plant species belonging to 26 botanic families. The majority of the individuals (79%) concentrated their foraging activity in five plant species. Individuals foraged all day long being the greatest activity between 8 h and 14 h. Similar proportions of young and old bees were sampled over the year. The density of substrates used for nesting was 4.56/ha. In total, 94% of the nests were found in branches of Agaristha revoluta (Spr.) DC. (Ericaceae). The great occurrence (68.7%) of old perforations indicates that the nests were used twice or more times by bees.

The influence of prior experience with artificial fruits on the ovipositioning behavior of Anastrepha fraterculus (Diptera, Tephritidae)

The South American fruit fly, Anastrepha fraterculus (Wiedemann, 1830) (Diptera, Tephritidae), is a leading pest of Brazilian fruit crops. This study evaluated how prior experience with artificial fruits containing peach and/or guabiroba pulp influenced the ovipositing behavior of A. fraterculus. Insects 15-21 days old were exposed to four treatments: 1) experience with guabiroba, Campomanesia xanthocarpa O. Berg (Myrtaceae); 2) experience with peach, Prunus persica (L.) Batsch (Chimarrita cultivar; Rosaceae); 3) experience with both fruits; and 4) no experience (naive). Naive females and females experienced with guabiroba pulp and with both fruits (peach and guabiroba) oviposited and showed dragging and puncturing behavior on substrates containing guabiroba, but females that were only exposed to peach pulp did not show a preference for any substrate. The study shows that prior experience with substrate influences ovipositing behavior in A. fraterculus.

Use of tree species by White-throated treerunner (Pygarrhichas albogularis King) in a secondary native forest of southern Chile

ABSTRACT In forest ecosystems, numerous species of insectivorous birds use certain tree species as feeding and nesting substrates. Between 2009 and 2010, the use of different floristic components as feeding substrate by the Pygarrhichas albogularis King, 1831 was evaluated in a southern Chilean secondary native forest. From a total of 13 trees and bush species, six tree species were used by P. albogularis as a feeding substrate. Tree use was limited to intermediate heights (11-20 m) and, mainly, to the trunk (40% of observations) and secondary branches (26%). Pygarrhichas albogularis showed a disproportionated use of N. dombeyi and an important use of trees with a greater age structure (DBH 81-100 cm). Nothofagus dombeyi presented a significantly greater tree bark crevice depth than E. cordifolia. In turn, covariance between crevice depth and invertebrate supply in tree bark was positive and significant. We consider bark depth and invertebrate supply to be the proximate causes explaining P. albogularis disproportionated use of Nothofagus dombeyi.

Poderá o carrapato transmitir a lepra?: isolamento e cultura dum bacilo acido-álcool resistente de sedimento de "Amblyomma cajennense" capturado em leproso: 2ª nota

In this 2nd note upon the possibility of transmission of human leprosy by ticks, the A. relates his stepps to obtain the collaboration of his colleagues working in leprosaria in various States of Brazil, Argentina and Paraguay in such studies. Firstly the A. describes the positive results of examination of sediment of ticks, the cattle tick Boophilus microplus (Canestrini, 1888), received from Paraná (Leprosário São Roque) , which were put on active lepers, two of them sucking during 9 days and one during 7 days. Two out of three were killed for examination and were very strongly positive for acid-fast bacilli. A series of tubes of Loewenstein medium was smeared with the sediment of such ticks. Secondly the A. relates his personnal experiment, carried out in Rio de Janeiro, trying to infect normal ticks in lepers. The experiment with Boophilus microplus was negative and was twicely positive the experiment with Amblyomma cajennense Fabricius, 1794. The experiment is being in progress and will be continued in other places of Brazil. Finally, after being given the general characteristics of Boophilus microplus, the A. describes the non-chromogenic culture of a acid-fast bacillus isolated by him from sediment of ticks (Amblyomma cajennense) captured in lepers from Colônia Santa Isabel (Minas gerais), which parasitism was spontaneous. The first isolation was obtained in Loewenstein medium after 62 days incubation at 37°C. The culture is pure and the bacillus is permanent acid-fast. The plate1, in full color, represents this culture in its four generations. The colonies are pearl-white in color, dry, elevated and rough, developing slowly and beginning as white pinhead points scattered upon the surface of the medium. The culture is not yet rich enough to be inoculated into laboratory animals, which will be done when possible.

Estudo bacteriológico de escarros de leprosos-tuberculosos em tratamento com a Estreptomicina

Fourteen samples of sputum from fourteen lepers with pulmonary tuberculosis, were treated by PETROFF method and its sediments were smeared on LOEWENSTEIN medium and incubated at 37°C. These fourteen patients are under treatment by Streptomycin. They are advanced cases of active leprosy associated with pulmonary tuberculosis, according to X ray diagnosis. Between 15 to 45 days thirteen out of fourteen (92,85%) sputa gave cultures of acid-fast bacilli with all characteristics of KOCH'S bacillus, eugonic type. Nine out of thirteen positive cases produced eugonic colonies in all ten tubes smeared with each sample. These facts proved that Streptomycin did not affect the pulmonary flora. Three out of fourteen patients died within two months after positive cultures of KOCH'S bacillus. New fact - Three out of those thirteen positive patients gave non-chromogenic cultures, eugonic type, associated with chromogenic ones, quite similar to cultures of acid-fast bacilli isolated previously by the author from leprous material. One of the three patients who died showed in smear of fresh sputum only characteristics globies (globies of MARCHOUX not globi of NEISSER) of HANSEN'S Bacillus. Probably he died from leprous-pneumonia. The eugonic type cultures are being inoculated in guinea-pigs and the choromogenic ones, similar to leprosy-culture, will be inoculated in white rats and mice.

The use of triphenyltetrazolium chloride in the study of dehydrogenase activity of Brucellae

Experiments for the investigation of dehydrogenase activity of washed cells of a strains of Br. abortus and another of Br. suis in presence of different single added substrates are reported. The activity was measured as the amount of formazan produced by the reduction of 2, 3, 5-triphenyltetrazolum chloride acting as a hydrogen ions acceptor, at pH 7.0. In a general manner the dehydrogenase activity of Br. suis was much more intense than that of Br. abortus (fig. 5). In the conditions of the experiments Br. abortus oxidized L-arabinose, D-galactose, D-glucose, glycerol, D-xylose, DL-alanine, D-fructose, and D-sorbitol. Brucella suis oxidized D-xylose, L-arabinose, D-glucose, D-galactose, DL-alanine, sodium acetate, maltose, glycine, D-fructose, and D-sorbitol. Glycerol was oxidized by Br. abortus but its oxidation by Br. suir was very slight. Sodium acetate and maltose were intensely oxidized by Br. suir but not by Br. abortus. The sites of more intense enzymatic acitivity were seen as small red colored round granules located in one pole of the cells.