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Avanços Científicos e Tecnológicos em Bioprocessos, O Brasil é um dos maiores produtores de etanol no mundo, no entanto, durante o processo de obtenção deste combustível, elevadas quantidades de vinhaça são geradas, em média, para cada litro de etanol produzido são gerados 13 litros deste resíduo. A vinhaça possui propriedades físicas e químicas que podem desencadear efeitos nocivos à biota, deste modo, existe um interesse crescente em identificar novas tecnologias para o seu tratamento. A utilização de células a combustível microbianas (CCMs) apresenta um enorme potencial, uma vez que, pode promover simultaneamente o tratamento deste resíduo e a biogeração de energia elétrica, pela conversão da energia química disponível nesses substratos biodegradáveis diretamente em eletricidade, por meio da ação catalítica de bactérias eletrogênicas aderidas ao eletrodo. Neste contexto, o presente estudo avaliou a utilização de uma CCM de câmara dupla no tratamento de vinhaça sintética. Durante a operação deste reator foi detectada uma máxima densidade de potência de 330 mW·m-2 e uma redução na demanda química de oxigênio (DQO) em 58,8% após 28 dias. Diante destes resultados preliminares, a tecnologia CCM pode ser considerada promissora no tratamento da vinhaça, contudo, estudos a respeito da configuração, tipo de inóculo e formas de operação da CCM são necessários para que amplie sua eficiência., Brazil is one of the largest producers of ethanol in the world, however, during the process of obtaining ethanol, high quantities of vinasse are generated, on average, for each liter of ethanol produced, 13 liters of this residue is generated. Vinasse has physical and chemical properties that can trigger harmful effects on biota, so there is a growing interest in identifying new technologies for its treatment. The use of microbial fuel cells (CCMs) presents a very high potential, since it can simultaneously promote the treatment of this residue and the biogeneration of electric energy, by converting the available chemical energy in these biodegradable substrates and directly into electricity, by means of the action of electrogenic bacteria adhered to the electrode. In this context, the present study evaluated the use of a double chamber CCM in the treatment of synthetic vinasse. During the operation of this reactor, a maximum power density of 330 mW m-2 and a reduction in chemical oxygen demand (COD) was detected at 58.8% after 28 days. Considering these preliminary results, CCM technology may be considered promising in the treatment of vinasse, however, studies regarding the configuration, type of inoculum and forms of CCM operation are necessary to increase its efficiency., info:eu-repo/semantics/publishedVersion

Urban and industrial wastewaters have received an increased interest towards energy harvesting using microbial fuel cells (MFC). The combined use of microbial anode oxidizing organic substrates and enzymatic cathode reducing oxygen is a promising new approach for the simultaneous treatment of wastewater and generation of electricity. In this context, our study evaluated the performance of a two-chambered MFC operated with three laccase producing strains of filamentous fungi (Ff), immobilized on the cathodic compartment and filled up with simulated textile dye effluent (TDE) and urban wastewater in the anodic compartment. The result indicated a rapid TDE decolourisation (>86 % within 72 h). Electrochemical monitoring of the MFC during TDE decolourisation indicated power density (>35 mW m2, control 3,61) and laccase activity (989.6 U l–1) in the presence of Pleurotus ostreatus on the cathodic compartment. Considering the initial COD value of 464 ± 20 mg.l-1, the organic removal in the anodic compartment after 20 days of MFC operation was 90.2%. Final toxicity measurements in the TDE treated indicated a much lower impact when compared to the original TDE. These are the initial studies to select Ff as models for MFC application and further adaptation for wastewater treatment and bioelectricity generation

Pectinases, or pectinolytic enzymes, are naturally produced by plants, filamentous fungi, bacteria and yeasts. The pectinases are of great importance to clarify and reduce viscosity in fruit juices, improving and increasing tbe filtration efficiency. When used in the crushing of grapes or wine must improve juice extraction, reduce the time to clarify and enhance tbe content ofterpenes in wine. The filamentous fungi most frequently used fur industrial purposes because as much as 90% ofthe enzyme can be excreted into the culture medium. The partitioning and purification of polygalacturonases (PG) produced by Aspergillus niger URM 5162 were investigated in aqueous two-phase systems (ATPS), furmed by polyetbylene glycol and phosphate salts (PE(ijlhosphate). To evaluate the effect oftbe 4 independent variables- molar mass ofpolyetbylene glycol (PEG) (400-8000 g1nol MPEG), PEG concentration (12.5-17.5%, w/w- CPEG), phosphate concentration (15-25%, ...W, CPHOS) and pH (6.0, 8.0) - on the 3 response variables: partition coefficient (K), activity yield (Y) and purification fàctor (PF), a fuctorial design (24) was used. The endo-polygalacturonases (endo-PG) were prefurentially partitioned in tbe top phase. For endo-PG, the highest values for the response variables K, Y and PF of 1.23, 74.04% and 8.18, respectively, were obtained for a CPEG of 12.5% (...W), MPEG of8000 g1nol, and CPHOS of25% (w/w) at pH 6.0. Also, exo-polygalacturonases (exo-PG) were preferentially partitioned in the top phase. ln tbis case, the highest values ofK (2.40), Y (33.33%), and PF (1.98) were obtained with a MPEG of 8000 g1nol, CPEG of 12.5% (...W), and CPHOS of25% (...W) at pH 6.0. ln both cases, MPEG had a positive influence on K, Y and PF. The conditions ofMPEG 8000 g1nol, CPEG of 12.5% (...W), and CPHOS of25% (...W) at pH 6.0 were considered the most suitable for tbe purification of PG produced by A. niger URM 5162. Furtbermore, MPEG and CPHOS were the most important independent variables. The PEG/phosphate system is a useful cost-effective altemative for PG purification.

Pectinases are a heterogeneous group of related enzymes that hydrolyze pectic substances present mostly in plants. Pectinases are produced by plants, fungi, yeasts and bacteria. Filamentous fungi are good producers of pectinolytic enzymes (e.g., exopolygalacturonase (exo-PG) and endopolygalacturonase (endo-PG) and Aspergillus niger is the most commonly used fungal species for industrial production of pectinolytic enzymes. The application of pectinolytic enzymes plays an important role in food technology. In juice production, these enzymes have been used to improve the yield, decrease the viscosity, clarify the juices and make them more stable. In this context, the concept of using filamentous fungi and row and cheaper materials for pectinase production is an important parameter in technological development. In the present study a microplate method was developed for a rapid screening of Aspergillus strains. Fifty-tree strains of Aspergillus section Nigri obtained from the University of Recife Mycology (URM) culture collection and 8 of the Micoteca da Universidade do Minho (MUM) culture collection were used. Orange peel was the unique carbon source in the composition of the culture medium. The samples were incubated at 25 ºC for 120 h. After 24, 48, 72, 96 and 120 h the exo-PG and endo-PG were assessed using absorbance colorimetric and decrease in viscosity methods, respectively. The utilization of orange peel allowed the detection of exo-PG and endo-PG activity for all strains studied. The maximum exo-PG and endo-PG activity was obtained by strain URM5162 to the values 4.37 U and 2.13 U, respectively. This method and substrate may be useful to reduce the time for selecting promising strains and in reducing the enzyme production costs. The strain is now being used in a bioreactor and the enzymes and their mechanisms are also under further investigation.

Lacases produzidas por fungos derivados de amostras marinhas são consideradas biotecnologicamente promissores, pois podem representar enzimas diferentes das produzidas por seus parceiros terrestres e possuem potencial aplicação biotecnológica em ambientes ou processos salinos. O objetivo do presente trabalho fui avaliar o efeito indutivo de íons cobre na síntese da enzima lacase por duas linhagens: Nigrospora sp. (02) e Arthopyrenia sa/icis (D4) isoladas da esponja marinha Dragmacidon reticulata, bem como detectar as isoformas desta enzima através de técnicas moleculares. As amostras foram fermentadas em frascos contendo 100 m1 do meio MA2 + 3% de NaCI, incubadas à 28 oCa 150 rpm por 7 dias, filtmdas a vácuo e mantidas em estufu a I 05 °C por 8 homs. A atividade da lacase fui determinada através da oxidação de seringaldazina (525 nm). Uma unidade de atividade enzimática foi definida pela altemção da abso!bância em 0.01 por minuto. Os respectivos DNA genômicos foram extraídos, amplificados com os primers degenemdos LAC3!7LAC3r, purificados, clonados em E. co/i JM109 e sequenciados. As sequências obtidas fomm montadas em um contig e comparadas com sequências do Genbank (Blastx). Na concentração de 5 mM de íons CuS04, foi observada uma elevação dos níveis enzimáticos e em concentrações acima de 5 mM, houve um redução na produção da enzima. No 5° dia de fermentação, Nigrospora sp. (02) apresentou um valor máximo de lacase (25.2 U L-I) que fui 3.9 vezes superior ao valor obtido com o controle. Nas concentrações de 1mM e lO mM de CuS04 houve um aumento de 2.6 e 3.0 vezes em relação ao controle, respectivamente. Em adição, a produção desta enzima pelo fungo Nigrospora sp. (02) fui 2.8 vezes superior a produção obtida comA. salicis (D4). Uma isoforma da enzima fui identificada a partir da amostra de Nigrospora sp. (02) e três isoformas a partir da amostra A. salicis (D4 ), as quais apresentaram similaridade de sequência entre 45 e 100% com lacase de um ascomiceto marinho Clavariopsis aquatica. Os resultados derivados do presente trabalho estimulam estudos subsequentes de otimização e caracterização das lacases produzidas pelos dois fungos ascomicetos recuperados de ambiente marinho., FAPESP - Fundação de Amparo à Pesquisa do Estado de São Paulo, Micoteca da Universidade do Minho

Four different white rot fungi were screened to study the decolourisation of the textile dyes Reactive Black 5 (RB5) and Poly R-478 on plates under alkaline condition. Three strains of Trametes versicolor (MUM 94.04 MUM 04.100 MUM 04.101) and one strain of Phanerochaete chrysosporium (MUM 94.15), showed better decolourisation results. The strains were used for decolourisation study in liquid culture medium (LCM). All four strains presented more efficient decolourisation on dye RB5, but they differed in decolourisation capacity depending on the analised pH value. In LCM the decolouration of dye reached 100% for the two strains of WRF studied.

The wastewater of textile industry contains not only dyes but also salts, surfactants and others substances and as extreme pH values. Among all dyes and pigments azo dyes are claimed to be between 60 to 70% of the environmental pollutants. Nowadays, environmental regulations in most countries require textile effluents to be decolourised before discharging. This led to the study of innovative and environmental friendly technologies. The extracellular ligninolytic enzyme system of white rot fungi (WRF) has been demonstrated to be very efficient in textile dye decolourisation. The purpose of the present work was to study the dye decolourisation of recalcitrant di-azo Reactive Black S (RBS) using WRF in bioreactor. The bioreactor was a 300 ml capacity chemostat with 260 ml working liquid volume assisted by a peristaltic pump. In order to reproduce the current composition of textile effluents the assay was carried out under extreme conditions of pH and salt concentration. Trametes versico/or (MUM 04.100) from Micoteca da Universidade do Minho Culture Collection was used. The decolourisation and the enzymatic activities of lignin peroxidase, manganese peroxidase, laccase and glioxidase were assessed during 28 days by continuous and constantly increased addition of a RBS solution (100 mg r 1 at pH 9.S and 1S gr1 of NaCl) to the bioreactor. The results showed that in spite of extreme pH and salt concentration the decolourisation by WRF achieved 91 to 99%. Laccase seemed to be the most efficient ligninolytic enzyme. Mechanisms of dyes degradation for this strain are now under study.

Recent genetic studies of the Tuareg have begun to uncover the origin of this semi-nomadic northwest African people and their relationship with African populations. For centuries they were caravan traders plying the trade routes between the Mediterranean coast and south-Saharan Africa. Their origin most likely coincides with the fall of the Garamantes who inhabited the Fezzan (Libya) between the 1st millennium BC and the 5th century AD. In this study we report novel data on the Y-chromosome variation in the Libyan Tuareg from Al Awaynat and Tahala, two villages in Fezzan, whose maternal genetic pool was previously characterized. High-resolution investigation of 37 Y-chromosome STR loci and analysis of 35 bi-allelic markers in 47 individuals revealed a predominant northwest African component (E-M81, haplogroup E1b1b1b) which likely originated in the second half of the Holocene in the same ancestral population that contributed to the maternal pool of the Libyan Tuareg. A significant paternal contribution from south-Saharan Africa (E-U175, haplogroup E1b1a8) was also detected, which may likely be due to recent secondary introduction, possibly through slavery practices or fusion between different tribal groups. The difference in haplogroup composition between the villages of Al Awaynat and Tahala suggests that founder effects and drift played a significant role in shaping the genetic pool of the Libyan Tuareg.

A large amount of azo dyes are used for dyeing textiles. However, the dyes contaminate wastewaters and need to be treated. This is important because of the aesthetic, toxic and carcinogenic effects of the affected waters. Recently there has been an increase in interest in using white rot fungi (wrf) which degrade xenobiotic compounds including azo dyes. Wrf degrade lignin and others recalcitrant molecules using nonspecific extracellular enzymes. Four white rot fungi obtained from the Micoteca da Universidade do Minho (MUM) culture collection were used to screen for degradability capabilities. Reactice Black 5 (RB5) was selected in the present work because these dyes are most commonly used in the textile dyeing. Screening for RB5 decolourisation was carried out on solid medium in plates. Two wrf showed good growth and decolourisation abilities. These are now under study to determine which ligninolytic enzymes are produced.

Reactive dyes are widely used in the textile industry. Coloured effluents from dyestuff and textile industries. the major producers and users of azo dyes. not only produce visual pollution but con also be detrimental to life. as they ore usually resistant to biological treatment. Additionally. fungi, mainly white rot fungi. have shown the ability to degrade numerous aromatic organopollutants. including textile dyes. via oxidative mechanisms till their complete mineralisation. avoiding the formation of anilines as intermediates. In our work. textile azo dyes were synthesized using aminobenzoic and ominosulphonic acids as diozo components and bioaccessible groups such as 2-methoxyphenol (guaiocol) and 2,6-dimethoxyphenol (syringol) as coupling components. The bioaccessible groups are present in the lignln structure and seem to be access points to the ligninolytic enzymes produced by white rot fungi. The fungal biodegrodation of the ozo dyes were studied in order to establish the relationship between the chemical structure of the dye and the extent of biodegrodation. The rule of the non-specific fungal ligninolytic enzymatic system, lignin peroxidoses. manganese peroxidases and loccoses. as well as the enzyme glyoxal oxidose wich produce H202 for the activities of both peroxidoses were studied. Reactive Black 5 and the anthraquinone-bosed polymeric dye Poly R-478 hove been currently used to screen the fungal biodegradation under alkaline conditions (pH ≥ 8.0). In order to adapt the fungi to this alkaline condition a chemostat is now used. To perform this work the fungi used were supplied by the culture collection Micoteca do Universidade do Minho (MUM).

Doze diferentes fungos da podridão branca da madeira foram selecionados para o estudo da descoloração dos corantes têxteis Reativo Preto 5 e Poly R-478 em meio sólido, em elevado teor de alcalinidade. Três linhagens de Trametes versicolor (MUM 94.04 MUM 04.100 MUM 04.101) e uma de Phanerochaete chrysosporium MUM 94.15, apresentaram os melhores resultados. Em meio de cultura liquido, estes quatro basidiomicetos foram extensivamente testados em diferentes condições alcalinas e em concentrações extremas de salinidade. MUM 94.04 e MUM 04.100 apresentaram capacidade de descoloração de 90% e 100%, respectivamente. O desempenho de MUM 04.100 em quimiostato a pH 9,5, atendeu a ordem de descoloração de 100% e atividade enzimática da lacase com valor máximo em 3,5U. Introdução As contaminações ambientais dos corpos de água, decorrente da emissão de efluentes provenientes principalmente do setor têxtil ganham atenção mundial nos dias atuais [1,2]. Legislações cada vez mais rígidas que destacam a água com todo seu valor agregado obrigam as indústrias deste setor a possuírem um prévio tratamento de seus descartes [3]. Novas tecnologias, cujo tratamento seja mais adequado, com baixos custos e ambientalmente amigáveis são o foco de muitas pesquisas neste setor [4]. O biotratamento utilizando-se fungos da podridão branca da madeira (Fpb) torna-se promissor em comparação aos convencionais, visto que é mais econômico e também não gera subprodutos muitas vezes mais tóxicos que os de origem [5]. Fpb possuem um mecanismo oxidativo inespecífico, que inclui enzimas extracelulares capazes de degradar uma grande variedade de organopoluentes, dentre eles corantes têxteis [6,7]. As principais enzimas extracelulares detectadas são, lacase (Lcc - EC.1.10.3.2), manganês-peroxidase (MnP - EC.1.11.1.13) e lignina peroxidase (LiP - EC.1.11.10.14). No entanto, raramente estas enzimas são expressas ao mesmo tempo por um microorganismo [8]. Adicionalmente às enzimas já supracitadas, bem como outras que têm tido menor atenção como a enzima glioxaloxidase (GLOX - EC.1.2.3.5), ainda necessitam de ser melhor compreendidas quanto ao seu papel na degradação destes compostos xenobióticos [9-11]. Deste modo, o presente trabalho teve por objetivo verificar a capacidade de descoloração de linhagens fúngicas proveninentes da Micoteca da Universidade do Minho (MUM) em condições extremas de alcalinidade e concentração de sais, para dois corantes da indústria têxtil, considerando-se que o efluente deste segmento possuem tais características.

β-Fructofuranosidase production by Aspergillus oryzae IPT301 was maximized in shake flasks. Response Surface Methodology (RSM) involving Small Central Composite Design was adopted to evaluate the fructosyltransferase (FTase) activity by changing three medium component concentrations: sucrose, urea and yeast extract. The optimal set of conditions for maximum fructosyltransferase production was as follows: sucrose 320.5 g/L, urea 7.13 g/L and yeast extract 2.11 g/L. In this optimal condition, the following improvements were achieved: an increase of 48.8% in cell growth, 112% and 62% in micelial and free FTase activities, respectively, 62.8% in the ratio of fructosyltransferase/hydrolytic activities for enzyme linked to mycelium and 67.5% for free enzyme.

The advent of asteroseismology as the golden path to precisely characterize single stars naturally led to synergies with the field of exoplanetology. Today, the precise determination of stellar masses, radii and ages for exoplanet-host stars is a driving force in the development of dedicated software and techniques to achieve this goal. However, as various approaches exist, it is clear that they all have advantages and inconveniences and that there is a trade-off between accuracy, efficiency, and robustness of the techniques. We aim to compare and discuss various modelling techniques for exoplanet-host red giant stars for which TESS data are available. The results of the seismic modelling are then used to study the dynamical evolution and atmospheric evaporation of the planetary systems. We study, in detail, the robustness, accuracy and precision of various seismic modelling techniques when applied to four exoplanet-host red giants observed by TESS. We discuss the use of global seismic indexes, the use of individual radial frequencies and that of non-radial oscillations. In each case, we discuss the advantages and inconveniences of the modelling technique. We determine precise and accurate masses of exoplanet-host red giant stars orbited by long-period Jupiter-like planets using various modelling techniques. For each target, we also provide a model-independent estimate of the mass from a mean density inversion combined with radii values from Gaia and spectroscopic data. We show that no engulfment or migration is observed for these targets, even if their evolution is extended beyond their estimated seismic ages up the red giant branch., Accepted for publication in Astronomy and Astrophysics. Part of the CASCADES series of papers