Estudo cinético da síntese do octanoato de n-Pentila catalisada pela enzima Lipozyme TL IM

Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico. Programa de Pós-Graduação em Engenharia QuímicaOs ésteres são importantes compostos orgânicos, utilizados em diversos setores industriais como petroquímica, alimentos, cosméticos, tintas e vernizes, entre outros. Uma grande aplicação deles está relacionada à sua utilização como aromas. Quando sintetizados utilizando enzimas como catalisador podem ser considerados aromas naturais, aumentando seu valor no mercado. Nesse trabalho estudou-se a obtenção do éster alifático (aroma) octanoato do n-pentila por esterificação direta utilizando enzima Lipozyme TL IM como catalisador. Foi verificada a influência da concentração inicial dos reagentes (0,1 a 0,95 mol.L-1) na velocidade inicial da reação em função da temperatura de síntese (30, 40 e 50 ºC). A velocidade inicial da reação foi determinada através do consumo de ácido octanóico ao longo do tempo. A concentração de ácido foi determinada por titulação ácido-base com solução alcoólica de KOH e o éster caracterizado por FTIR. Modelos cinéticos encontrados na literatura foram ajustados aos dados experimentais. Os resultados obtidos demonstram que a enzima sofre inibição em concentrações iniciais de substrato acima de 0,65 mol.L-1, para qualquer valor de temperatura utilizada. A velocidade máxima atingida pela reação possui valores aproximados de 0,0067, 0,0092 e 0,0080mol.L-1.min-1 para 30, 40 e 50ºC, respectivamente. O modelo proposto por Wu e colaboradores se adaptou bem ao comportamento reação. Os parâmetros Ki= 0,738 0,032 mol.L-1e n= 17,11 1,83 mostraram ser independentes da temperatura. O parâmetro Vm mostrou ser afetado pelo efeito da temperatura, apresentando valores de 0,0163 (30 ºC), 0,0298 (40ºC) e 0,0155(50ºC)mol.L-1.min-1. Para o parâmetro Ks ele variou de maneira dependente a Vmax atingindo valores de 0,969, 1,473 e 0,702 mol.L-1 para as temperaturas de 30, 40 e 50ºC respectivamente. A enzima pode ser reutilizada por aproximadamente 6, 16 e 26 vezes para as temperaturas de 50, 40 e 30ºC, respectivamente. A maior quantidade de éster produzida pode ser obtida à temperatura de 30ºC (0,057 mol) para bateladas de 10 mL com concentração inicial dos reagentes igual a 0,65 mol.L-1

Reator anaeróbio de manta de lodo e biofiltro em polietileno como alternativa de tratamento descentralizado para esgoto sanitário no município de Rio Rufino - SC

Basic sanitation services are essential for promoting public health and for mitigating environmental damage. Thus, the objective of this work was to evaluate a wastewater treatment system consisting of anaerobic sludge blanket reactor and biofilter, as an alternative for the decentralized wastewater treatment in the municipality of Rio Rufino - Santa Catarina. The system was evaluated for its efficiency of removal of fecal coliforms, biochemical oxygen demand, chemical oxygen demand, soluble chemical oxygen demand, phosphorus, Total Kjhedal Nitrogen, nitrite, nitrate, sedimentable solids and maintenance of the hydrogen potential in the effluent. The treated effluent had its parameters compared to the standards established by Resolution 430/2011 of the Conselho Nacional do Meio Ambiente and Law 14.675 / 2009 of the State of Santa Catarina. It was also performed the estimate of the daily biochemical oxygen demand load, originated by the population of the municipality, and its respective impact. The effluent treated by the proposed system, when properly installed, follows what was established by the legislation, which implies in reducing the impacts caused by the municipality. In this way, the system can be an interesting alternative when it comes to decentralized wastewater treatment.Serviços de saneamento básico são essenciais para a promoção da saúde pública e para a mitigação de danos ambientais. Deste modo, o presente trabalho teve como objetivo avaliar um sistema de tratamento de efluentes domésticos constituído de reator anaeróbio de manta de lodo e biofiltro, como alternativa para o tratamento descentralizado de esgoto sanitário no município de Rio Rufino – Santa Catarina. O sistema foi avaliado pela eficiência referente a remoção de coliformes fecais, demanda bioquímica de oxigênio, demanda química de oxigênio, demanda química de oxigênio solúvel, fósforo, Nitrogênio Total Kjhedal, nitrito, nitrato, sólidos sedimentáveis e manutenção do potencial hidrogeniônico no efluente. O efluente tratado teve seus parâmetros comparados aos padrões estabelecidos pela Resolução 430/2011 do Conselho Nacional do Meio Ambiente e a Lei 14.675/2009 do Estado de Santa Catarina. Também foi realizada a estimativa da carga de demanda bioquímica de oxigênio diária, originada pela população do município, e seu respectivo impacto. O efluente tratado pelo sistema proposto, quando instalado de forma adequada, apresentou-se em acordo com o estabelecido pela legislação, o que implica na redução dos impactos causados pelo município. Desta forma, o sistema pode vir a ser uma alternativa interessante, quando se trata de tratamento descentralizado de esgoto sanitário

Extracts of Leaves of Ficus auriculata Lour.: Antioxidant, Antimicrobial and Phytotoxic Activity

Ficus auriculata Lour. is a tree of the genus Ficus. The aim of this study was to obtain the total phenolic compounds; and to determine the antioxidant (DPPH), antimicrobial (diffusion disc and Minimal Inhibitory Concentration) and phytotoxic activity (in cucumber - Cucumis sativus L.) of the extracts. Five extraction methods were used to obtain extracts of young and mature leaves of F. auriculata: water/ethanol (M1), water/ethanol/ultrasound (M2), water/ethanol/cellulase complex (M3), water (M4) and water/cellulase complex (M5). The phenolic content for extracts of young leaves was of 30.22 ± 2.99 mg GAE.g-1 dry sample (M1), 35.22 ± 0.53 mg GAE.g-1 dry sample (M2) and 28.90 ± 0.57 mg GAE.g-1 dry sample (M3) and for the mature leaves of 24.42 ± 0.04 mg GAE.g-1 dry sample (M2) and 17.13 ± 4.69 mg GAE.g-1 dry sample (M1). For the antioxidant activity, the lowest values of IC50 (or higher antioxidant activity) occurred for the extracts of young and mature leaves obtained by the M2. The extracts were able to inhibit all the evaluated bacteria, presenting MICs in the range of 21.60–90.32 µg.ml-1 for the Escherichia coli, 21.60-188.85 µg.ml-1 for the Salmonella enteritidis, 64.22-188.85 µg.ml-1 for the Staphylococcus aureus and 76.31-87.82 µg.ml-1 for the Listeria monocytogenes. The extracts of young and adult leaves presented herbicide potential, occurring suppression of the growth of cucumber plants. The use of the extract obtained in M3 led to the death of the plants. Extracts of F. auriculata presented antioxidant and antimicrobial activities, which agree with previous studies linking phenolic compounds to these properties

Extracts of Leaves of Ficus auriculata Lour.: Antioxidant, Antimicrobial and Phytotoxic Activity

Ficus auriculata Lour. is a tree of the genus Ficus. The aim of this study was to obtain the total phenolic compounds; and to determine the antioxidant (DPPH), antimicrobial (diffusion disc and Minimal Inhibitory Concentration) and phytotoxic activity (in cucumber - Cucumis sativus L.) of the extracts. Five extraction methods were used to obtain extracts of young and mature leaves of F. auriculata: water/ethanol (M1), water/ethanol/ultrasound (M2), water/ethanol/cellulase complex (M3), water (M4) and water/cellulase complex (M5). The phenolic content for extracts of young leaves was of 30.22 ± 2.99 mg GAE.g-1 dry sample (M1), 35.22 ± 0.53 mg GAE.g-1 dry sample (M2) and 28.90 ± 0.57 mg GAE.g-1 dry sample (M3) and for the mature leaves of 24.42 ± 0.04 mg GAE.g-1 dry sample (M2) and 17.13 ± 4.69 mg GAE.g-1 dry sample (M1). For the antioxidant activity, the lowest values of IC50 (or higher antioxidant activity) occurred for the extracts of young and mature leaves obtained by the M2. The extracts were able to inhibit all the evaluated bacteria, presenting MICs in the range of 21.60–90.32 µg.ml-1 for the Escherichia coli, 21.60-188.85 µg.ml-1 for the Salmonella enteritidis, 64.22-188.85 µg.ml-1 for the Staphylococcus aureus and 76.31-87.82 µg.ml-1 for the Listeria monocytogenes. The extracts of young and adult leaves presented herbicide potential, occurring suppression of the growth of cucumber plants. The use of the extract obtained in M3 led to the death of the plants. Extracts of F. auriculata presented antioxidant and antimicrobial activities, which agree with previous studies linking phenolic compounds to these properties

Extracts of branches and fruits of Ficus auriculata Lour: antioxidant, antimicrobial and phytotoxic activities

The present study aimed to obtain the phenolic compounds from Ficus auriculata Lour fruits and branches and to determine the antioxidant and antimicrobial activities and phytotoxicity. For this purpose, five extraction methodologies were used, containing water and ethanol as solvents, low-frequency ultrasound and a cellulases complex. The antioxidant activity was determined by eliminating the DPPH radical. Antimicrobial activity was determined against Gram-positive and Gram-negative bacteria, through disk diffusion and minimum inhibitory concentration. The extracts were also used for tests of phytotoxicity in cucumber (Cucumis sativus L.). The contents of total phenolic compounds showed up to 16.16 mg GAE·g-1 and 22.56 GAE·g-1 for the extracts obtained from the branches and by aqueous and enzymatic extraction. The highest antioxidant activity was found in the extract of the branches obtained with the mixture of ethanol and water and the use of ultrasound, with an IC50 value of 190.57 µg.mL-1. Extracts from branches and fruits showed antimicrobial activity against all tested microorganisms, with inhibition halos of up to 17 mm and minimum inhibitory concentrations of 25.5 μg.mL-1 to 122.25 μg.mL-1. The extracts showed phytotoxicity against cucumber seeds, with a 30% reduction in growth compared to the control. The extracts from the branches and fruits of F. auriculata have biological potential in relation to the tested activities and the difference in these was demonstrated according to the form of extraction

Extracts of branches and fruits of Ficus auriculata Lour: antioxidant, antimicrobial and phytotoxic activities

The present study aimed to obtain the phenolic compounds from Ficus auriculata Lour fruits and branches and to determine the antioxidant and antimicrobial activities and phytotoxicity. For this purpose, five extraction methodologies were used, containing water and ethanol as solvents, low-frequency ultrasound and a cellulases complex. The antioxidant activity was determined by eliminating the DPPH radical. Antimicrobial activity was determined against Gram-positive and Gram-negative bacteria, through disk diffusion and minimum inhibitory concentration. The extracts were also used for tests of phytotoxicity in cucumber (Cucumis sativus L.). The contents of total phenolic compounds showed up to 16.16 mg GAE·g-1 and 22.56 GAE·g-1 for the extracts obtained from the branches and by aqueous and enzymatic extraction. The highest antioxidant activity was found in the extract of the branches obtained with the mixture of ethanol and water and the use of ultrasound, with an IC50 value of 190.57 µg.mL-1. Extracts from branches and fruits showed antimicrobial activity against all tested microorganisms, with inhibition halos of up to 17 mm and minimum inhibitory concentrations of 25.5 μg.mL-1 to 122.25 μg.mL-1. The extracts showed phytotoxicity against cucumber seeds, with a 30% reduction in growth compared to the control. The extracts from the branches and fruits of F. auriculata have biological potential in relation to the tested activities and the difference in these was demonstrated according to the form of extraction

Characterization and evaluation of potential impacts in the environment of residual fiber from cellulose

The search for final alternative destinations for residue from industrial processes is a growing problem. Pulp and paper industries generate large amounts of residue, which are not always reused or do not receive an adequate destination. An alternative is its reuse, using the final disposal of the residue in the soil, for its potential to inactivate part of the chemical compounds, allowing its use as agricultural inputs of low cost. The purpose of this study was to analyze the final residue of the wastewater treatment plant of a pulp and paper industry. Industries in this economic sector produce high resistance and low lignin cellulose pulp and recover the chemicals used, reducing costs. In order to pre-evaluate this disposal possibility, this study carried out the classification of the waste classifying the hazardousness of the cellulose fiber, and its behavior under solubilization and leaching tests. The results of the analysis showed the potential of solubilization of substances in water above the maximum permissible value (MPV), characterizing the residue as non-inert and non-hazardous Class IIA. This fact implies that safety doses must be evaluated before its application in soil. Further studies must be carried out in terms of toxicological effects and its potential to be applied to crops.A busca por destinações finais alternativas para os resíduos de processos industriais é uma problemática crescente. As indústriasde papel e celulosegeram grandes quantidades deresíduos, que nem sempre são reutilizados ou não recebem a destinação adequada. Uma alternativa é seu reaproveitamento, utilizando a disposição final do resíduo no solo, pelo potencial do mesmo em inativar parte dos compostos químicos, possibilitando seu uso como insumos agrícolas de baixo custo. Este estudo teve por finalidade analisar o resíduo final da estação de tratamento deefluentesde uma indústria de papel e celulose. Indústrias deste setor produzemuma polpa de celulose de alta resistência e com baixoteor de lignina, alémderecuperar os químicos utilizados, diminuindo custos.De forma a pré-avaliar esta possibilidadede disposição, este estudo realizou a classificação do resíduo classificando a periculosidade da fibra de celulose, e seu comportamentosob ensaios de solubilização e lixiviação.As análises conduzidas demonstraramcaracterísticas de solubilização de substâncias em água acima dos níveis de valor máximo permitido (VMP), caracterizando o resíduo como não inerte enãoperigoso Classe IIA. Isso significa que doses seguras devem ser estudadas antes de sua aplicação no solo. Estudos adicionais devem avaliaros efeitos toxicológicose o seu potencial na agricultura.  

Characterization and evaluation of potential impacts in the environment of residual fiber from cellulose

The search for final alternative destinations for residue from industrial processes is a growing problem. Pulp and paper industries generate large amounts of residue, which are not always reused or do not receive an adequate destination. An alternative is its reuse, using the final disposal of the residue in the soil, for its potential to inactivate part of the chemical compounds, allowing its use as agricultural inputs of low cost. The purpose of this study was to analyze the final residue of the wastewater treatment plant of a pulp and paper industry. Industries in this economic sector produce high resistance and low lignin cellulose pulp and recover the chemicals used, reducing costs. In order to pre-evaluate this disposal possibility, this study carried out the classification of the waste classifying the hazardousness of the cellulose fiber, and its behavior under solubilization and leaching tests. The results of the analysis showed the potential of solubilization of substances in water above the maximum permissible value (MPV), characterizing the residue as non-inert and non-hazardous Class IIA. This fact implies that safety doses must be evaluated before its application in soil. Further studies must be carried out in terms of toxicological effects and its potential to be applied to crops

The use of enzymes in the dairy industry: a condensed review

The main aim of this paper is to show an overview of the technical aspects of enzymatic action in milk processing. Process indicator enzymes, just as alkaline phosphatase and lactoperoxidase, have widely been employed in dairy factories for thermal treatment validation. However, the development of new strategies for microbiological control in milk represents a challenge for maintaining its usage. New sources of milk clotting enzymes have been studied in order to replace the calves’ sourced enzymes and enhance the specificity for milk processing uses. Immobilization of enzymes also has been studied looking for improve usability, storage, and stability of enzymes in dairy products manufacturing. Immobilized enzymes are studied to be employed for several purposes in milk processing, just as clotting or hydrolyzing agents. The use of encapsulated enzymes is important for cheese ripening, avoiding taste or texture depletion along the ripening period

Os sentidos apontando para uma nova transformação, de Hélio Oiticica

Este texto foi escrito para o Simpósio de “arte tátil” realizado este ano (12 de  julho  de  1969)  na  Universidade Estadual da Califórnia em  Long  Beach  – Lygia Clark e eu fomos convidados. O texto pretende mostrar e definir as possíveis  relações  com  o  sujeito  e,  também,  as  profundas  diferenças,  indicando  os pontos em comum entre os trabalhos de ambos e a procura de um novo exercício de comunicação que, ao invés de uma busca por “invenções formais”, sirva como uma verdadeira linha de pensamento para lidar com os desafios da atualidade