Genome sequencing of cells that live inside glass cages reveals their past history

One-quarter of the total primary production on earth is contributed by diatoms1. These are photosynthetic, unicellular algae with ornamented silica shells found in all aquatic and moist environments. They form the base of energy-efficient food webs that support all aquatic life forms. More than 250 genera of living diatoms, with as many as 100,000 species are known2. Fossil diatoms are known as early as the Cretaceous, 144–65 m.y. ago3. In India, deposits of diatoms occur in Rajasthan and are known as ‘multani mitti’. Multani mitti or Indian Fuller’s earth or diatomaceous earth as it is called in the West, is applied as a paste on the surface of the skin for 15–20 min and then washed-off. This leaves the skin feeling smooth, soft, moist and rejuvenated. Diatomaceous earth is now being used in the formulation of soaps, cleansing products, face powders and skincare preparations. Diatomaceous earth is a mineral material consisting mainly of siliceous fragments of various species of fossilized remains of diatoms.

Microbial life and deposits in paper machine circuits

Väitöskirjani käsittele mikrobien ja erilaisten kemikaalien rooleja saostumien ja biofilmien muodostumisessa paperi- ja kartonkikoneilla. "Saostuma" tässä työssä tarkoittaa kiinteän aineen kertymää konepinnoille tai rajapinnoille konekierroissa, jotka on tarkoitettu massasulppujen, lietteiden, vesien tai ilman kuljetukseen. Saostumasta tulee "biofilmi" silloin kun sen oleellinen rakennekomponentti on mikrobisolut tai niiden tuotteet. Väitöstyöni työhypoteesina oli, että i. tietämys saostumien koostumuksesta, sekä ii. niiden rakenteesta, biologisista, fysikaalis-kemiallisista ja teknisistä ominaisuuksista ohjaavat tutkijaa löytämään ympäristöä säästäviä keinoja estää epätoivottujen saostumien muodostus tai purkaa jo muodostuneita saostumia. Selvittääkseni saostumien koostumista ja rakennetta käytin monia erilaisia analytiikan työkaluja, kuten elektronimikroskopiaa, konfokaali-laser mikroskopiaa (CLSM), energiadispersiivistä röntgenanalyysiä (EDX), pyrolyysi kaasukromatografiaa yhdistettynä massaspektrometriaan (Py-GCMS), joninvaihtokromatografiaa, kaasukromatografiaa ja mikrobiologisia analyysejä. Osallistuin aktiivisesti innovatiivisen, valon takaisinsirontaan perustuvan sensorin kehittämistyöhön, käytettäväksi biofilmin kasvun mittaukseen suoraan koneen vesikierroista ja säiliöistä. Työni osoitti, että monet paperinvalmistuksessa käytetyistä kemikaaleista reagoivat keskenään tuottaen orgaanisia tahmakerroksia konekiertojen teräspinnoille. Löysin myös kerrostumia, jotka valomikroskooppisessa tarkastelussa oli tulkittu mikrobeiksi, mutta jotka elektronimikroskopia paljasti alunasta syntyneiksi, alumiinihydroksidiksi joka saostui pH:ssa 6,8 kiertokuitua käyttävän koneen viiravesistä. Monet paperintekijät käyttävät vieläkin alunaa kiinnitysaineena vaikka prosessiolot ovat muuttuneet happamista neutraaleiksi. Sitä pidetään paperitekijän "aspiriinina", mutta väitöstutkimukseni osoitti sen riskit. Löysin myös orgaanisia saostumia, joiden alkuperä oli aineiden, kuten pihkan, saippuoituminen (kalsium saippuat) niin että muodostui tahmankasvua ylläpitävä alusta monilla paperi- ja kartonkikoneilla. Näin solumuodoiltaan Deinococcus geothermalista muistuttavia bakteereita kasvamassa lujasti teräskoepalojen pintaan kiinnittyneinä pesäkkeinä, kun koepaloja upotettiin paperikoneiden vesikiertoihin. Nämä deinokokkimaiset pesäkkeet voivat toimia jalustana, tarttumisalustana muiden mikrobien massoille, joka selittäisi miksi saostumat yleisesti sisältävät deinokokkeja pienenä, muttei koskaan pääasiallisena rakenneosana. Kun paperikoneiden käyttämien vesien (raakavedet, lämminvesi, biologisesti puhdistettu jätevesi) laatua tutkitaan, mittausmenetelmällä on suuri merkitys. Koepalan upotusmenetelmällä todettu biofilmikasvu ja viljelmenetelmällä mitattu bakteerisaastuneisuus korreloivat toisiinsa huonosti etenkin silloin kun likaantumisessa oli mukana rihmamaiseti kasvavia bakteereja. Huoli ympäristöstä on pakottanut paperi- ja kartonkikoneiden vesikiertojen sulkemiseen. Vesien kierrätys ja prosessivesien uudelleenkäyttö nostavat prosessilämpötilaa ja lisäävät koneella kiertävien kolloidisten ja liuenneiden aineiden määriä. Tutkin kiertovesien pitoisuuksia kolmessa eriasteisesti suljetussa tehtaassa, joiden päästöt olivat 0 m3, 0,5 m3 ja 4 m3 jätevettä tuotetonnia kohden, perustuen puhdistetun jäteveden uudelleen käyttöön. Nollapäästöisellä tehtaalla kiertovesiin kertyi paljon orgaanisesti sidottua hiiltä (> 10 g L-1), etenkin haihtuvina happoina (maito-, etikka-, propioni- ja voi-). Myös sulfaatteja, klorideja, natriumia ja kalsiumia kertyi paljon, > 1 g L-1 kutakin. Pääosa (>40%) kaikista bakteereista oli 16S rRNA geenisekvenssianalyysien tulosten perusteella sukua, joskin etäistä (< 96%) ainoastaan Enterococcus cecorum bakteerille. 4 m3 päästävältä tehtaalta löytyi lisäksi Bacillus thermoamylovorans ja Bacillus coagulans. Tehtaiden saostumat sisälsivät arkkeja suurina pitoisuuksina, ≥ 108 g-1, mutta tunnistukseen riittävää sekvenssisamanlaisuutta löytyi vain yhteen arkkisukuun, Methanothrix. Tutkimustulokset osoittivat että tehtaan vesikiertojen sulkeminen vähensi rajusti mikrobiston monimuotoisuutta, muttei estänyt liuenneen aineen ja kiintoaineen mineralisoitumista.

Biotransformations of α-terpineol in the rat: Its effects on the liver microsomal cytochrome P-450 system

Alpha-Terpineol (I), a monocyclic monoterpene tertiary alcohol, is widely used in the manufacture of perfumes, cosmetics, soaps and antiseptic agents. It was reported earlier (Horning et al. 1976) that this monoterpene alcohol when administered to humans is hydroxylated to p-menth-l,2,8-triol (II). It is not known whether c~-terpineol also produces other metabolites during its metabolism in the mammalian system and if so, the nature of these metabolites.

Delamination of oil paints from acrylic grounds

Many modern artists paint in oil or oil-modified alkyd paints over acrylic grounds. In some cases the oil based paints do not remain adhered to the ground. In a set of composite samples of oil or alkyd paints, over acrylic grounds, naturally aged for nine years, some of the samples delaminated. Samples were analyzed with X-ray fluorescence (XRF), inductively coupled plasma (ICP), Fourier transform infrared - attenuated total reflectance (FTIR-ATR), scanning electron microscopy (SEM), pyrolysis gas-chromatography mass-spectrometry (PY-GC/MS), laser desorption/ionization mass-spectrometry (LDI-MS), atomic force microscopy (AFM) and other methods, in order to find what the delaminating ones have in common. In addition, two examples of severely delaminating paintings were examined, to confirm the results from the laboratory-prepared samples. Results indicate the main cause of delamination is metal soaps in the oil paint and particularly zinc soaps. There is some evidence that metal soaps were more concentrated at the interface between the layers and this disrupted the adhesion. The ground is a minor consideration as well, rougher grounds providing better adhesion than smooth ones.

Spéciation chimique des nanoparticules d'argent dans les sols

À cause de leurs propriétés antibactériennes, les nanoparticules d’argent sont couramment utilisées dans un grand nombre de produits tels les tissus, les savons et les produits médicaux. Dans cette industrie en pleine croissance, ces nanoparticules sont produites en grandes quantités et s’accumuleront éventuellement dans l’environnement. Pour comprendre le destin, le transport et la biodisponibilité des nanomatériaux, il est essentiel de comprendre leurs propriétés physicochimiques. Entre autres, il est particulièrement important de quantifier la dissolution des nanoparticules à l’aide de mesures de spéciation chimique. En effet, l’objectif de cette recherche est de déterminer la spéciation chimique des nanoparticules d’argent dans différents sols. Pour y parvenir, différentes concentrations de nanoparticules d’argent ont été incorporées dans un sol et après un certain laps de temps, la forme ionique a été mesurée à l’aide d’une électrode sélective d’argent tandis que l’argent total est mesuré par absorption atomique ou par ICP-MS. L’analyse de la spéciation dans trois sols différents révèle que les caractéristiques des sols influencent grandement la spéciation chimique, plus particulièrement la quantité de matière organique ainsi que le pH du sol. Ainsi, la tendance des résultats semble indiquer que plus un sol est acide, il y aura plus d’ions argent libres tandis que la matière organique adsorbe fortement les ions argent les rendant ainsi moins disponibles en solution. L’observation de la spéciation chimique à long terme indique aussi que les nanoparticules tendent à éventuellement se dissocier et ainsi émettre un plus grand nombre d’ions dans l’environnement. Ces résultats ont des implications importantes dans la détermination des risques environnementaux des nanoparticules métalliques.

Realitätsnähe von Kinderfernsehprogrammen und geschlechterspezifische Fernsehnutzungspräferenzen

Überblick über die Arbeit: "Die Notwendigkeit deutscher Kinderfernseh- und -filmproduktion ist unbestritten. Sie sind die Voraussetzung dafür, dass Kinder im Fernsehen ihre eigene Lebenswirklichkeit wiederfinden und zur Reflexion dieser Wirklichkeit angeregt werden."(Rosenbaum 2000) Kinderfernsehexperten wie Uwe Rosenbaum (Landessenderdirektor des Südwestrundfunks Rheinland-Pfalz) oder Armin Maiwald (Geschäftsführer der Flash Filmstudio GmbH, Produzent und Regisseur vieler Sachgeschichten der Sendung mit der Maus) vertreten die Meinung, dass in Deutschland mehr Kinderprogramm mit Kindern produziert werden müsse, die in Deutschland wohnen. Sie sind dabei auch der Meinung, Realprogramm sei qualitativ hochwertiger und damit für Kinder besser, als einseitiges, triviales Zeichentrickprogramm. Der Teil 1 greift diesen Diskurs auf und beschreibt ihn. Einen Beitrag zu diesem Diskurs möchte die Frageleisten, welche Darstellungsformen von Welt vom expliziten Kinderfernsehen angeboten werden und welche davon Kinder bevorzugen. Das Material einer systematischen Fernsehprogrammanalyse, die von den Nutzungspräferenzen der Kinder ausgeht, kann dabei helfen. Dabei konzentriere ich mich auf die zwei Aspekte "Animation" und "real", da der Diskurs Realfilm als qualitativ hochwertig ansieht und Animation in dieser Hinsicht das genaue Gegenteil darstellt. Dabei ist ein zentrales Ergebnis der Analyse, dass sich die Nutzungspräferenzen der Jungen und Mädchen in bezug auf realitätsnahes Programm sehr unterscheiden: Jungen sehen eher Zeichentrickprogramm und Mädchen sehen eher Realformate wie z.B. Soap-Operas. Das legt nahe, die Diskussion um Realitätsnähe im Kinderfernsehen aus geschlechterspezifischer Sicht zu betrachten und die Fragestellung der Arbeit dahingehend neu zu formulieren. Der zweite Teil der Arbeit sortiert zunächst die Begriffe "Realitätsnähe", "Realfilm" und "Zeichentrick", die im ersten Teil eingeführt wurden und trennt sie von einander. Die "Jährliche Bestandsaufnahme zum Kinderfernsehen - qualitative und quantitative Fernsehprogrammanalyse in der Sicht der Kinder" dient dazu, im Kinderfernsehen die Spuren des Diskurses wieder zu finden. Die systematische Suche nach solchen Programmen macht es nötig, mit Hilfe operationalisierter Begriffe, Fernsehprogramm zu kodieren. Dabei bieten sich bereits vorhandene Kodes zur Realitätsnähe an. Für die Auswertung sind zudem auch Zugänge über weitere Kodes wie z.B. Information/ Unterhaltung oder Fiction/ Non-Fiction möglich. Die Ansätze in Teil 1 und 2 waren bis dahin umgangssprachliche Formulierungen, deshalb folgt im dritten Teil der Arbeit ein Exkurs in die Theorie, um den Begriff der Realitätsnähe im Fernsehen theoretisch zu begründen und um Realfilm und Animation theoretisch zu beschreiben. Zwei Themenfelder sind hierbei wesentlich: Das erste Themenfeld behandelt die Wirklichkeitskonstruktion im Fernsehen mit den Autoren Alfred Schütz, Thomas Luckmann und Jürgen Fritz. Das Wesentliche in diesem Abschnitt ist der Versuch Realfilm und Zeichentrick als geschlossene Sinngebiete wie "reale Welt" und "Spielwelt" zu verstehen, da geschlossenen Sinngebieten spezifische, eigene Erlebnis- und Erkenntnisstile zugrunde liegen. Fazit dieser Überlegung ist, dass Realfilm und Zeichentrick einander nicht über- oder untergeordnet sind, sondern formal nebeneinander mit unterschiedlichen Erkenntnis- und Erlebnisstilen in Erscheinung treten, bzw. in ihnen unterschiedliche Erlebnis- und Erkenntnisstile angelegt sind. Das zweite Themenfeld widmet sich der von David Buckingham so genannten "Perceived Reality", die nach der Wahrnehmung der Kinder von Wirklichkeit im Fernsehen fragt. Dabei geht es um die Frage, wie Kinder die Realität des Fernsehens beurteilen. Ein Fazit ist hierbei, dass Kinder an Fernsehsendungen keine allgemeingültige Messlatte anlegen, um die Realitätsnähe zu bestimmen, sondern Kinder handeln die Realitätsnähe von Sendungen und deren Bewertung in sozialen Kontexten mit Peers und Erwachsenen je nach Situation aus. Der vierte Teil der Arbeit wertet die Kodierung aus dem zweiten Teil aus und präsentiert Ergebnisse. In diesem Teil werden verschiedene Auswertungsverfahren ausprobiert, um Muster in der Rezeption und im Ein- und Ausschaltverhalten der Kinder in bezug auf Realitätsnähe zu finden. Nachdem Überblick über das Angebot an realitätsnahem Kinderfernsehprogramm, folgt die Auswertung der Nutzung des Kinderprogramms. Hierbei steht die Frage im Vordergrund, in welchem Ausmaß Kinder realitätsnahe Programme nutzen und welche geschlechterspezifischen Unterschiede es in der Nutzung Formate "Animation" und "real" gibt. Im Groben werden in diesem Kapitel zahlreiche Listen präsentiert, Sendungen beschrieben und vor allem unterschiedliche Altersgruppen sowie Geschlechter berücksichtigt. Eines der auffälligsten Merkmale wird sein, dass Jungen in Bezug auf die eingangs eröffneten Begriffe andere Präferenzen und Fernsehnutzungsmuster zeigen als Mädchen. Im Gegensatz zu Mädchen sehen die Jungen eher weniger Realprogramm und eher mehr Animationsprogramm. Kinder im Fernsehen stehen stellvertretend für Muster und Typen von Kindern der realen Welt. Das legitimiert anhand der Typologie der Kinder nach Freizeitmustern , nach diesen Kindertypen im Fernsehen und bei den Zuschauern zu suchen. Ein Ergebnis bestätigte die Beobchtung, dass Mädchen neben Realprogramm auch Zeichentrick sehen, und Jungen nur Zeichentrick. Anhand der bis dort gewonnenen Ergebnisse und zweier Beispiele aus dem Schulalltag folgt abschließend in Teil 5 ein pädagogisches Fazit. Der Umgang von Jungen mit Medien wird häufig problematisiert und so wie es sich in den Ergebnissen dieser und anderer Arbeiten wie der PISA2000-Studie oder in der Typologie der Freizeitmuster darstellt, könnte man durchaus den Eindruck gewinnen, dass Jungen eine schwierige Beziehung zu Medien haben. Deshalb muss man sich vermutlich zunächst eingestehen, dass Jungen eher Zeichentrick und Mädchen eher Soaps gucken, um danach Jungen emphatisch in Bezug auf ihre Mediennutzungsmuster zu begegnen und ihre Vorlieben nicht zu trivialisieren oder zu verurteilen. Das hat pädagogische Bedeutung für die Schule, wie die beiden Beispiele zeigen.

Jabones El Tigre y Roca S.A., estudio estratégico para ingreso a mercados internacionales

Jabones El Tigre y Roca S.A. es una compañía productora y comercializadora de jabones en barra y detergentes para el lavado de ropa y de jabones en pasta para la limpieza de la loza. Con el presente trabajo enmarcado dentro de las etapas descriptiva, de diagnóstico y prescriptiva, se pretende analizar y evaluar la situación actual de la empresa y a su vez dar alternativas de exportación para el producto detergente presentando recomendaciones que pueden orientar futuras decisiones.

Effect of impurities in biodiesel-derived waste glycerol on the performance and feasibility of biotechnological processes

The rapid development of biodiesel production technology has led to the generation of tremendous quantities of glycerol wastes, as the main by-product of the process. Stoichiometrically, it has been calculated that for every 100 kg of biodiesel, 10 kg of glycerol are produced. Based on the technology imposed by various biodiesel plants, glycerol wastes may contain numerous kinds of impurities such as methanol, salts, soaps, heavy metals and residual fatty acids. This fact often renders biodiesel-derived glycerol unprofitable for further purification. Therefore, the utilization of crude glycerol though biotechnological means represents a promising alternative for the effective management of this industrial waste. This review summarizes the effect of various impurities-contaminants that are found in biodiesel-derived crude glycerol upon its conversion by microbial strains in biotechnological processes. Insights are given concerning the technologies that are currently applied in biodiesel production, with emphasis to the impurities that are added in the composition of crude glycerol, through each step of the production process. Moreover, extensive discussion is made in relation with the impact of the nature of impurities upon the performances of prokaryotic and eukaryotic microorganisms, during crude glycerol bioconversions into a variety of high added-value metabolic products. Finally, aspects concerning ways of crude glycerol treatment for the removal of inhibitory contaminants as reported in the literature are given and comprehensively discussed

Fatty acid composition of intramuscular fat from Nellore steers fed dry or high moisture corn and calcium salts of fatty acids

The purpose of this work was to evaluate the fatty acid composition of the Longissimus muscle from carcasses of Nellore steers fed diets with calcium salts of fatty acids (CSFA) and high moisture corn. Forty eight steers were fed during 70 days four diets containing dry corn (DC), high moisture corn (HM). dry corn plus CSFA (DC-CSFA) or high moisture corn plus CSFA (HM-CSFA). Fatty acid composition of the Longissimus muscle was determined by gas chromatography. Corn type had no effect on the ether extract percentage and in the content of the majority of the fatty acids, although steers fed HMC showed higher levels of polyunsaturated fatty acids and polyunsaturated/saturated ratio. Feeding CSFA increased ether extract percentage but had no effect on total of saturated, unsaturated and saturated: unsaturated ratio. Both high moisture corn and calcium salts of fatty acids increased CIA (cis9, trans11) and total CIA concentrations in intramuscular fat (C) 2008 Elsevier B.V. All rights reserved.

Genotoxicity and mutagenicity of Rosmarinus officinalis (Labiatae) essential oil in mammalian cells in vivo

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Influence of domestic sewage leakage on the collapse of tropical soils

In the studied region, 35% of the soil collapses are related to leakage from sewage ducts. The paper describes the soils from this part of Brazil and a series of laboratory tests undertaken using water and domestic sewage fluid as the wetting agents. It is considered that the presence of soaps and detergents as recorded by the sodium concentration facilitates the densification of the soils and hence has a major effect on the surface settlement/collapse.

Counterion effects on the structure and solubilization properties of anionic detergents. Role of hydrophobic cations in stabilizing micelles and attenuating their solvent properties

A series of alkyl sulfate detergents has been investigated in the presence of the cations Na +, methylviologen(2+) (MV 2+), 4-(cyanomethyl)pyridinium(1+) (CMP +), and tetramethylammonium (TMA +). The binding of these ions to the aqueous micellar assemblies has been measured through studies of luminescence quenching with the extramicellar probe, RuL 34-, where L = 4,4′-dicarboxy-2,2′-bipyridine. A general comparison of the alkyl sulfate aggregates with the nonquenching cations Na + and TMA + shows that the latter ion reduces the critical micelle concentration but at the same time depresses the ability of the detergent assemblies to bind or solubilize the hydrophobic quencher cations MV 2+ or CMP +. The reduced binding ability of the TMA + aggregates compared to that of the corresponding Na + soaps shows up largely in the form of a reduced favorable ΔS° for the solubilization in the case of the former. The results are in accord with a picture of the TMA + micelle as being more stable and more disordered than the corresponding assembly with Na + as the counterion. © 1989 American Chemical Society.

A preliminary physicochemical, exergetic and economic study of hydrogen production utilizing glycerol

This work has as objective to demonstrate technical and economic viability of hydrogen production utilizing glycerol. The volume of this substance, which was initially produced by synthetic ways (from oil-derived products), has increased dramatically due mainly to biodiesel production through transesterification process which has glycerol as main residue. The surplus amount of glycerol has been generally utilized to feed poultry or as fuel in boilers, beyond other applications such as production of soaps, chemical products for food industry, explosives, and others. The difficulty to allocate this additional amount of glycerol has become it in an enormous environment problem, in contrary to the objective of biodiesel chain, which is to diminish environmental impact substituting oil and its derivatives, which release more emissions than biofuels, do not contribute to CO2-cycle and are not renewable sources. Beyond to utilize glycerol in combustion processes, this material could be utilized for hydrogen production. However, a small quantity of works (theoretical and experimental) and reports concerning this theme could be encountered. Firstly, the produced glycerol must be purified since non-reacted amounts of materials, inclusively catalysts, contribute to deactivate catalysts utilized in hydrogen production processes. The volume of non-reacted reactants and non-utilized catalysts during transesterification process could be reutilized. Various technologies of thermochemical generation of hydrogen that utilizes glycerol (and other fuels) were evaluated and the greatest performances and their conditions are encountered as soon as the most efficient technology of hydrogen production. Firstly, a physicochemical analysis must be performed. This step has as objective to evaluate the necessary amount of reactants to produce a determined volume of hydrogen and determine thermodynamic conditions (such as temperature and pressure) where the major performances of hydrogen production could be encountered. The calculations are based on the process where advance degrees are found and hence, fractions of products (especially hydrogen, however, CO2, CO, CH4 and solid carbon could be also encountered) are calculated. To produce 1 Nm3/h of gaseous hydrogen (necessary for a PEMFC - Proton Exchange Membrane Fuel Cell - containing an electric efficiency of about 40%, to generate 1 kWh), 0,558 kg/h of glycerol is necessary in global steam reforming, 0,978 kg/h of glycerol in partial oxidation and cracking processes, and 0,782 kg/h of glycerol in autothermal reforming process. The dry reforming process could not be performed to produce hydrogen utilizing glycerol, in contrary to the utilization of methane, ethanol, and other hydrocarbons. In this study, steam reforming process was preferred due mainly to higher efficiencies of production and the need of minor amount of glycerol as cited above. In the global steam reforming of glycerine, for one mole of glycerol, three moles of water are necessary to produce three moles of CO2 and seven moles of H2. The response reactions process was utilized to predict steam reforming process more accurately. In this mean, the production of solid carbon, CO, and CH4, beyond CO2 and hydrogen was predicted. However, traces of acetaldehyde (C2H2), ethylene (C2H4), ethylene glycol, acetone, and others were encountered in some experimental studies. The rates of determined products obviously depend on the adopted catalysts (and its physical and chemical properties) and thermodynamic conditions of hydrogen production. Eight reactions of steam reforming and cracking were predicted considering only the determined products. In the case of steam reforming at 600°C, the advance degree of this reactor could attain its maximum value, i.e., overall volume of reactants could be obtained whether this reaction is maintained at 1 atm. As soon as temperature of this reaction increases the advance degree also increase, in contrary to the pressure, where advance degree decrease as soon as pressure increase. The fact of temperature of reforming is relatively small, lower costs of installation could be attained, especially cheaper thermocouples and smaller amount of thermo insulators and materials for its assembling. Utilizing the response reactions process in steam reforming, the predicted volumes of products, for the production of 1 Nm3/h of H2 and thermodynamic conditions as cited previously, were 0,264 kg/h of CO (13% of molar fraction of reaction products), 0,038 kg/h of CH4 (3% of molar fraction), 0,028 kg/h of C (3% of molar fraction), and 0,623 kg/h of CO2 (20% of molar fraction). Through process of water-gas shift reactions (WGSR) an additional amount of hydrogen could be produced utilizing mainly the volumes of produced CO and CH4. The overall results (steam reforming plus WGSR) could be similar to global steam reforming. An attention must to be taking into account due to the possibility to produce an additional amount of CH4 (through methanation process) and solid carbon (through Boudouard process). The production of solid carbon must to be avoided because this reactant diminishes (filling the pores) and even deactivate active area of catalysts. To avoid solid carbon production, an additional amount of water is suggested. This method could be also utilized to diminish the volume of CO (through WGSR process) since this product is prejudicial for the activity of low temperature fuel cells (such as PEMFC). In some works, more three or even six moles of water are suggested. A net energy balance of studied hydrogen production processes (at 1 atm only) was developed. In this balance, low heat value of reactant and products and utilized energy for the process (heat supply) were cited. In the case of steam reforming utilizing response reactions, global steam reforming, and cracking processes, the maximum net energy was detected at 700°C. Partial oxidation and autothermal reforming obtained negative net energy in all cited temperatures despite to be exothermic reactions. For global steam reforming, the major value was 114 kJ/h. In the case of steam reforming, the highest value of net energy was detected in this temperature (-170 kJ/h). The major values were detected in the cracking process (up to 2586 kJ/h). The exergetic analysis has as objective, associated with physicochemical analysis, to determine conditions where reactions could be performed at higher efficiencies with lower losses. This study was performed through calculations of exergetic and rational efficiencies, and irreversibilities. In this analysis, as in the previously performed physicochemical analysis, conditions such as temperature of 600°C and pressure of 1 atm for global steam reforming process were suggested due to lower irreversibility and higher efficiencies. Subsequently, higher irreversibilities and lower efficiencies were detected in autothermal reforming, partial oxidation and cracking process. Comparing global reaction of steam reforming with more-accurate steam reforming, it was verified that efficiencies were diminished and irreversibilities were increased. These results could be altered with introduction of WGSR process. An economic analysis could be performed to evaluate the cost of generated hydrogen and determine means to diminish the costs. This analysis suggests an annual period of operation between 5000-7000 hours, interest rates of up to 20% per annum (considering Brazilian conditions), and pay-back of up to 20 years. Another considerations must to be take into account such as tariffs of utilized glycerol and electricity (to be utilized as heat source and (or) for own process as pumps, lamps, valves, and other devices), installation (estimated as US$ 15.000 for a plant of 1 Nm3/h) and maintenance cost. The adoption of emission trading schemes such as carbon credits could be performed since this is a process with potential of mitigates environment impact. Not considering credit carbons, the minor cost of calculated H2 was 0,16288 US$/kWh if glycerol is also utilized as heat sources and 0,17677 US$/kWh if electricity is utilized as heat sources. The range of considered tariff of glycerol was 0-0,1 US$/kWh (taking as basis LHV of H2) and the tariff of electricity is US$ 0,0867 US$/kWh, with demand cost of 12,49 US$/kW. The costs of electricity were obtained by Companhia Bandeirante, localized in São Paulo State. The differences among costs of hydrogen production utilizing glycerol and electricity as heat source was in a range between 0,3-5,8%. This technology in this moment is not mature. However, it allows the employment generation with the additional utilization of glycerol, especially with plants associated with biodiesel plants. The produced hydrogen and electricity could be utilized in own process, increasing its final performance.

Verificação da atividade antibacteriana de sabonete líquido contendo extrato glicólico de Dimorphandra mollis Benth.

Dimorphandra mollis Benth., Compositae, false barbatimão, has been used topically as a healing, astringent and antibacterial. In this study, antibacterial activity was verified on liquid soap containing glycolic extract of D. mollis (DGE) at different concentrations (8, 15 and 20%) and at different pH levels (6 and 8). Five soap formulations (F) were prepared: F1 - tryclosan (0.1%), F2 - DGE (8%), F3 - DGE (15%), F4 - DGE (20%) and F5 - without preservatives. Bark of D. mollis were dried in a circulating air oven and ground. The rude extracts were prepared by turbo extraction with ethanol. After screening, the extract were concentrated in rotating evaporator, lyophilized and resuspended in propileneglycol to obtain the glycolic extract. The antimicrobial activity was verified by diffusion in agar method, using cylinder in plate. Plates containing Staphylococcus aureus, Pseudomonas aeruginosa and Escherichia coli were incubated at 37°C for 24 hours. After incubation, the results were analysed with a pachymeter, observing the bacterial grouth inhibition halo diameter. It was verified that the liquid soap containing tryclosan caused on inhibition of bacterial growth at both pH levels; the soaps without preservatives and containing DGE, independently of the concentration and pH levels used, did not present antibacterial activity.

Characterization of a glucose- and solvent-tolerant extracellular tannase from Aspergillus phoenicis

Tannases have attracted wider attention because of their biotechnological potential, especially enzymes from filamentous fungi and other microorganisms. However, the biodiversity of these microorganisms has been poorly explored, and few strains were identified for tannase production and characterization. This article describes the production, purification and characterization of a glucose- and solvent-tolerant extracellular tannase from Aspergillus phoenicis. High enzymatic levels were obtained in Khanna medium containing tannic acid up to 72 h at 30 °C under 100 rpm. The purified enzyme with 65% of carbohydrate content had an apparent native molecular mass of 218 kDa with subunits of 120 kDa and 93 kDa and was stable at 50 °C for 1 h. Optima of temperature and pH were 60 °C and 5.0-6.5, respectively. The enzyme was not affected significantly by most ions, detergents and organic solvents. While glucose did not affect the tannase activity, the addition of a high concentration of gallic acid did. The Km values were 1.7 mM (tannic acid), 14.3 mM (methyl-gallate) and 0.6 mM (propyl-gallate). The enzyme was able to catalyze the transesterification reaction to produce propyl-gallate. All biochemical properties suggest the biotechnological potential of the glucose- and solvent-tolerant tannase from A. phoenicis. © 2012 Elsevier B.V. All rights reserved.