RESUMO A avaliação nutricional em mangueiras baseada em métodos diagnósticos que consideram o equilíbrio nutricional tem sido recomendada. Os objetivos deste estudo foram: estabelecer faixas nutricionais ótimas por métodos diagnósticos e compará-las entre si; identificar o método diagnóstico mais eficiente na determinação de desequilíbrios nutricionais; e selecionar os nutrientes que melhor respondem à aplicação do método diagnóstico. O estudo foi realizado em pomares comerciais de mangueira no Vale do São Francisco-PE, Brasil. Foram calculados os teores nutricionais pelos métodos Sistema Integrado de Diagnóstico e Recomendação (DRIS-Beaufils, DRIS-Jones), DRIS Modificado (M-DRIS-Beaufils; M-DRIS-Jones), Diagnose da Composicão Nutricional (CND) e Chance Matemática (ChM) e comparados entre si pelo teste qui-quadrado. A análise de componentes principais foi aplicada para selecionar o método diagnóstico mais eficiente e os nutrientes responsáveis pela maior variabilidade. Os métodos DRIS Beaufils, M-DRIS Beaufils, DRIS Jones, M-DRIS Jones, CND e ChM geraram faixas de suficiência nutricional para as cultivares avaliadas. Os diagnósticos nutricionais dos métodos DRIS-Beaufils e M-DRIS Beaufius foram semelhantes entre si e discordantes dos métodos DRIS-Jones, M-DRIS-Jones e CND que foram semelhantes. O método DRIS Beaufils atualizado por Maia mostrou-se mais consistente na avaliação nutricional de mangueiras. Os nutrientes N, P, K, Mg e S na cultivar Tommy Atkins; N, P, Mg, S, B, Mn, Zn, Mo e Cl na cultivar Kent; e N, P, K, Ca, S, B, Cu, Fe, Zn, Mo e Cl na cultivar Keitt apresentam potencial de resposta significativa à aplicação do método DRIS-Beaufils atualizado por Maia. recomendada comparálas compará las FranciscoPE, FranciscoPE Francisco PE, PE Francisco-PE Brasil DRISBeaufils, DRISBeaufils (DRIS-Beaufils DRISJones, DRISJones Jones , DRIS-Jones) MDRISBeaufils M (M-DRIS-Beaufils MDRISJones, MDRISJones M-DRIS-Jones) (CND (ChM quiquadrado. quiquadrado qui quadrado. quadrado qui-quadrado variabilidade MDRIS avaliadas DRIS-Jones mostrouse mostrou se N P K Atkins B Mn Zn Kent Ca Cu Fe

ABSTRACT Nutritional assessment of mango trees based on diagnostic methods considering nutritional balance is recommended. This study aimed to establish optimum nutritional ranges using diagnostic methods, compare them, identify the most efficient diagnostic method, and select the nutrients responding best to the application of the diagnostic method. The study was conducted in commercial mango orchards in the São Francisco Valley. Nutritional content was calculated using the diagnosis and recommendation integrated system (DRIS-Beaufils, DRIS-Jones), modified DRIS (M-DRIS-Beaufils; M-DRIS-Jones), compositional nutrient diagnosis (CND), and mathematical chance (ChM) methods and compared using the chi-square test. Principal component analysis was applied to select the most efficient diagnostic method and the nutrients responsible for the greatest variability. The DRIS-Beaufils, M-DRIS-Beaufils, DRIS-Jones, M-DRIS-Jones, CND, and ChM methods generated nutritional sufficiency ranges for the evaluated cultivars. The nutritional diagnoses of the DRIS-Beaufils and M-DRIS-Beaufils methods were similar and discordant with those of DRIS-Jones, M-DRIS-Jones, and CND. The DRIS-Beaufils method, updated by Maia, proved to be more consistent for the nutritional assessment of mango trees. The nutrients N, P, K, Mg, and S in the Tommy Atkins cultivar; N, P, Mg, S, B, Mn, Zn, Mo, and Cl in the Kent cultivar; and N, P, K, Ca, S, B, Cu, Fe, Zn, Mo, and Cl in the Keitt cultivar showed significant responses to the application of the DRIS-Beaufils method updated by Maia. recommended them Valley DRISBeaufils, DRISBeaufils Beaufils, Beaufils (DRIS-Beaufils DRISJones, DRISJones Jones , DRIS-Jones) MDRISBeaufils M (M-DRIS-Beaufils MDRISJones, MDRISJones M-DRIS-Jones) CND (CND) (ChM chisquare chi square test variability MDRISBeaufils, Jones, DRIS-Jones M-DRIS-Jones cultivars Maia N P K Mg B Mn Zn Mo Ca Cu Fe (CND

RESUMO A região do Vale do São Francisco no Brasil destaca-se na exportação de frutos de manga. O diagnóstico nutricional prévio pode identificar estresses, antecipar a correção de limitações nutricionais e promover um manejo nutricional da fertilização mais eficiente. O estudo objetivou comparar o diagnóstico nutricional em mangueiras nas fases de pós-colheita e pré-florescimento e correlacionar com a produtividade. Normas e índices do Sistema Integrado de Diagnose e Recomendação foram geradas para cada fase fenológica das mangueiras, bem como o Índice de Balanço Nutricional e o Potencial de Resposta a Adubação. Os teores e faixas ótimas de nutrientes foram estabelecidos e classificados em deficientes, equilibrados ou excessivos. Esses teores e faixas ótimas de nutrientes foram comparados entre si e com valores recomendados na literatura. Os índices foram correlacionados com a produtividade dos pomares em cada fase fenológica das mangueiras. Ao comparar as normas DRIS das fases fenológicas pós-colheita e pré-floração, 55% das médias diferiram. As faixas de suficiência das fases pós-colheita e pré-floração, em geral, foram diferentes das referenciadas na literatura. Os diagnósticos nutricionais para os nutrientes P, K, Ca, Mg, S, Zn e Cl diferiram entre as fases fenológicas. O diagnóstico nutricional realizado na fase de pós-colheita mostrou que o desequilíbrio nutricional afetou a produtividade. destacase destaca se manga estresses eficiente póscolheita pós colheita préflorescimento pré florescimento Adubação deficientes excessivos literatura préfloração, préfloração floração, floração pré-floração 55 geral P K Ca Mg S 5

ABSTRACT The São Francisco Valley region of Brazil is a leading exporter of mango fruits. Previous nutritional diagnosis can identify stresses, provide adjustments for nutritional limitations, and promote more efficient fertilization and nutrient management. This study aimed to compare the nutritional diagnosis of mango trees in the post-harvest and pre-flowering phases and to correlate them with productivity. Norms and indices of the Integrated System of Diagnosis and Recommendation (DRIS), as well as the Nutritional Balance Index and the Potential of Response to Fertilization were generated for each phenological phase of the mango trees. Optimal concentrations and ranges of nutrients were established, classified as deficient, balanced, or excessive, and subsequently compared to each other and to values recommended in the literature. The indices were correlated with the productivity of the orchards in each phenological phase of the mango trees. When comparing the DRIS norms of post-harvest and pre-flowering phenological phases, 55% of the averages differed. The sufficiency ranges of the post-harvest and pre-flowering phases were generally different from those referenced in the literature. Nutritional diagnoses for P, K, Ca, Mg, S, Zn, and Cl altered between phenological phases. The nutritional diagnosis performed in the post-harvest phase showed that nutritional imbalance affected productivity. fruits stresses limitations management postharvest post harvest preflowering pre flowering DRIS, , (DRIS) established deficient balanced excessive literature 55 differed P K Ca Mg S Zn (DRIS 5

RESUMO O cultivo de fruteiras é influenciado por fatores abióticos como o manejo nutricional. Contudo, os fertilizantes são usados em grandes quantidades em vinhedos, resultando no excesso de nutrientes que podem causar estresse e reduzir a qualidade dos frutos. O Ca é um dos nutrientes mais utilizados nos vinhedos devido aos seus efeitos na qualidade dos frutos. Entretanto, o excesso de Ca interfere na distribuição das suas frações nos frutos, sendo uma forma de estresse abiótico. O objetivo desse estudo foi avaliar a influência do balanço nutricional da uva de mesa na nutrição cálcica e qualidade dos frutos. Foram selecionados 19 pomares de uvas de mesa no Vale do Submédio São Francisco nas safras de 2019 e 2020. Foi realizado o diagnóstico nutricional utilizando o sistema integrado de diagnose e recomendação (DRIS) e calculado o índice do balanço nutricional médio (IBNm) médio. O teor de Ca-pectato, Ca-total, firmeza da baga, sólidos solúveis, acidez titulável, razão sólidos solúveis/acidez titulável e matéria seca foram determinados nos frutos. O diagnóstico nutricional identificou excesso de Ca. A correlação entre Ca-pectato e o IBNm médio foi negativa, indicando que o teor de Ca-pectato é maior em videiras mais desbalanceadas nutricionalmente. Contudo, o Ca-total no fruto não teve correlação com Ca-pectato. O Ca-total e o Ca-pectato não se correlacionaram com a firmeza da baga. A nutrição cálcica é complexa e evidencia a importância de associar a avaliação do balanço nutricional com o Ca na qualidade dos frutos para otimizar o manejo nutricional da videira. Contudo Entretanto abiótico 1 201 2020 DRIS (DRIS (IBNm Capectato, Capectato pectato, pectato Catotal, Catotal total, total baga solúveis solúveisacidez negativa nutricionalmente Capectato. pectato. videira 20 202 2

ABSTRACT The cultivation of fruit trees is influenced by abiotic factors such as nutritional management. However, fertilizers are used in large amounts in vineyards, resulting in excess nutrients that can cause stress and reduce fruit quality. Calcium (Ca) is one of the most used nutrients in vineyards due to its effects on fruit quality. However, excess of Ca interferes with the distribution of Ca compounds in fruits, being a form of abiotic stress. The aim of this study was to evaluate the influence of the nutritional balance of table grape orchards on calcium nutrition and fruit quality. Nineteen table grape orchards were selected in the Submédio São Francisco Valley in 2019 and 2020 crops. The nutritional diagnosis was performed using the integrated diagnosis and recommendation system (DRIS) and the average nutritional balance index (NBIm) was calculated. The concentration of Ca-pectate, Ca-total, berry firmness, soluble solids, titratable acidity, soluble solids/titratable acidity ratio and dry matter were determined in the fruits. The nutritional diagnosis identified excess Ca in the orchards. The correlation between Ca-pectate and the average NBIm was negative, indicating that the Ca-pectate concentration is higher in vines that are more nutritionally unbalanced. However, the Ca-total in the fruit was not correlated with Ca-pectate. Ca-total and Ca-pectate were not correlated with berry firmness. Calcium nutrition is complex and highlights the importance of associating the assessment of nutritional balance with Ca in fruit quality to optimize the nutritional management of the grapevine. However (Ca fruits 201 202 crops DRIS (DRIS (NBIm calculated Capectate, Capectate pectate, pectate Catotal, Catotal total, total firmness solids solidstitratable negative unbalanced Capectate. pectate. grapevine 20 2

RESUMO O nitrogênio (N) é o nutriente mais limitante ao desenvolvimento da cana-de-açúcar e com a utilização de variedades mais produtivas e exigentes, as doses utilizadas na adubação nitrogenada na cana planta podem estar subestimadas e os teores críticos de N na folha poderão sofrer modificações. O objetivo da pesquisa foi determinar a curva de diluição dos teores críticos de N (CNDC) na folha, avaliar a produção da massa seca da parte aérea (ADM) e a produtividade de duas variedades de cana-de-açúcar em relação à adubação nitrogenada. A pesquisa foi realizada em condições de campo, sendo avaliadas as variedades RB92579 e RB867515, quando adubadas com sete doses de N (0, 30, 60, 90, 120, 150 e 200 kg ha-1). As variedades e doses de N foram dispostas em blocos casualizados com quatro repetições sob o esquema fatorial de 2 × 7. O teor de N na folha reduziu com o aumento da ADM e se ajustou ao modelo exponencial que permitiu estimar os teores críticos de 13,03 e 12,46 g de N kg-1 de matéria seca nas variedades RB92579 e RB867515, respectivamente. A cana planta respondeu positivamente à adubação nitrogenada e aumentou em 18,66% a tonelada de colmos por hectare (TCH) com adição de até 129,45 kg ha-1 de N. A variedade RB92579 apresentou menor diluição do teor crítico do N, maior produção de ADM e maior produtividade de colmos, sendo considerada mais eficiente na utilização do N-fertilizante.

ABSTRACT Nitrogen is the most limiting nutrient for the development of sugarcane and particularly the use of more productive and demanding varieties, for which the doses of nitrogen fertilization necessary during the plant cane cycle may be underestimated and the critical levels of nitrogen in the leaf may be modified. The objective of this study was to determine the critical nitrogen dilution curve (CNDC) for leaves, evaluate the aboveground dry mass production (DM) and productivity of two varieties fertilized with N in the plant cane cycle. The study was conducted under field conditions, evaluating two sugarcane varieties RB92579 and RB867515, fertilized with seven doses of N (0, 30, 60, 90, 120, 150 and 200 kg ha-1). The varieties and doses were arranged in randomized blocks and analyzed in the 2 × 7 factorial scheme. It was found that the nitrogen concentration in the leaf decreased with four repetitions increase in DM yield and adjusted an exponential model, which enabled to estimate the critical levels of 13.03 and 12.46 g N kg-1 dry matter in the varieties RB92579 and RB867515, respectively. The plant cane cycle were observed to respond positively to nitrogen fertilization, with increase of 18.66% in tons of stalk per hectare (TSH) in response to the application addition of up to 129.45 kg N ha-1. The variety RB92579 showed the lowest dilution of the critical nitrogen concentration, the highest production of DM and higher stalk yield, and accordingly is considered to be the more efficient of the two varieties with respect to nitrogen fertilizer utilization.

BACKGROUND: Elastic resistance bands (ERB) combined with proprioceptive neuromuscular facilitation (PNF) are often used in resistance muscle training programs, which have potential effects on peripheral muscle strength. However, the effects of the combination of ERB and PNF on respiratory muscle strength warrant further investigation. OBJECTIVES: The assessment of the effects of PNF combined with ERB on respiratory muscle strength. METHOD: Twenty healthy, right-handed females were included. Subjects were randomized to either the resistance training program group (TG, n=10) or the control group (CG, n=10). Maximal expiratory pressure (MEP) and inspiratory pressure (MIP) were measured before and after four weeks of an upper extremity resistance training program. The training protocol consisted of upper extremity PNF combined with ERB, with resistance selected from 1 repetition maximum protocol. RESULTS: PNF combined with ERB showed significant increases in MIP and MEP (p<0.05). In addition, there were significant differences between the TG and CG regarding ∆MIP (p=0.01) and ∆MEP (p=0.04). CONCLUSIONS: PNF combined with ERB can have a positive impact on respiratory muscle strength. These results may be useful with respect to cardiopulmonary chronic diseases that are associated with reduced respiratory muscle strength.

Uma das principais propriedades a serem estabelecidas para o desenvolvimento de vacinas seguras e atenuadas de flavivirus,é a taxa de replicação viral. Neste trabalho, aplicamos a metodologia de amplificação pela reação em cadeia da polimerase em tempo real e titulação viral por plaqueamento para determinação da replicação do vírus 17DD (FA 17DD) e recombinantes, expressando proteínas do envelope de dengue sorotipos 2 e 4 (17D-DENV-2 e 17D-DENV-4). As amostras de soros de macacos inoculados por via intracerebral ou subcutânea com FA 17DD ou 17D-DENV foram usadas para determinar e comparar a viremia induzida por estes vírus. A quantificação da carga viral em amostras de macacos inoculados por ambas as vias com FA 17DD sugere restrita capacidade de replicação com taxa não superior a 2,0 log10 PFU mL-1 ou 3,29 log10 cópias/mL-1. Os vírus recombinantes 17D-DENV mostraram-se tão atenuados quanto o vírus 17DD, tanto porRT-PCR em tempo real quanto por plaqueamento, com título médio máximo de 1,97 log10 PFU mL-1 ou 3,53 log10 cópias/mL-1. Estes dados servem como base comparativapara caracterização de outros vírus vivos atenuados, derivados do vírus 17D, candidatos a vacinas contra outras doenças.

For the development of safe live attenuated flavivirus vaccines one of the main properties to be established is viral replication. We have used real-time reverse transcriptase-polymerase chain reaction and virus titration by plaque assay to determine the replication of yellow fever 17DD virus (YFV 17DD) and recombinant yellow fever 17D viruses expressing envelope proteins of dengue virus serotypes 2 and 4 (17D-DENV-2 and 17D-DENV-4). Serum samples from rhesus monkeys inoculated with YFV 17DD and 17D-DENV chimeras by intracerebral or subcutaneous route were used to determine and compare the viremia induced by these viruses. Viral load quantification in samples from monkeys inoculated by either route with YFV 17DD virus suggested a restricted capability of the virus to replicate reaching not more than 2.0 log10 PFU mL-1 or 3.29 log10 copies mL-1. Recombinant 17D-dengue viruses were shown by plaquing and real-time PCR to be as attenuated as YF 17DD virus with the highest mean peak titer of 1.97 log10 PFU mL-1 or 3.53 log10 copies mL-1. These data serve as a comparative basis for the characterization of other 17D-based live attenuated candidate vaccines against other diseases.

Many industrial processes produce effluents with a wide variety of xenobiotic organic pollutants, which cannot be efficiently degraded by conventional biological treatments. Thus, the development of new technologies to eliminate these refractory compounds in water has become very imperative in order to assure the quality of this important resource. Ozonation is a very promising process for the treatment of wastewaters containing non-easily removable organic compounds. The present work aims at highlighting new methods of enhancing the efficiency of ozone towards the removal organic pollutants in aqueous solution. Special attention is given to catalytic ozonation processes contemplating homo- and heterogeneous catalysis, their activity and mechanisms. Recent results and future prospects about the application of these processes to real effluents are also evaluated.

Cerium based-compounds have great importance in a wide range of technological applications, such as: fuel cell devices development; metallurgic processes, petroleum refining; glass and ceramic production. Recently, its catalytic properties have been also explored for environmental applications, especially those to prevent or to control atmospheric and water pollution. Subjects covered in this work include a brief description of the fundaments of cerium catalytic properties and some relevant technological applications. Special attention is given to its photocatalytic activity and its ability to degrade pollutants. Recent results and future prospect about these applications are also evaluated.

Neste trabalho é apresentado um método eficiente para a degradação de corantes, usando uma fonte de pó de ferro zero ambientalmente amigável (resíduo de um processo industrial). A influência de vários fatores experimentais (tais como: pH, massa de ferro, tamanho de partícula, concentração do substrato, atmosfera inerte ou oxidante) sobre a eficiência do ferro zero em reduzir o grupo cromóforo e o teor de carbono orgânico total de um azocorante (Preto Remazol B) foi avaliada. O processo de degradação do corante apresentou uma cinética de primeira ordem com uma constante de 0,153 min-1. Nas condições otimizadas (pH=3, [Fe] = 5 g L-1, tamanho de partícula < 250 µm), este processo promoveu uma descoloração de 95% e redução de 70% na concentração de carbono orgânico total de uma solução 100 mg L-1 do corante. Este processo também foi empregado na degradação de um efluente industrial têxtil apresentando bons resultados e demonstrando capacidade para ser uma alternativa para a remediação de sistemas aquáticos poluídos.

In this paper an efficient method for azo dye degradation using an environmentally friendly zero-valent iron powder source is presented (iron particles discarded from a manufacturing process). The influence of several experimental parameters (such as pH, iron mass, particle size, substrate concentration, oxidizing and inert atmospheres) on the ability of zero-valent iron to reduce the chromophoric groups and total organic carbon content of the azo dye Remazol Black B was evaluated. Kinetic studies revealed that the azo degradation by Fe0 appeared to be first-order with respect to substrate, with an observed rate constant (k obs) of 0.153 min-1. Under the optimized operational conditions (pH 3, [Fe] = 5 g L-1, iron particle size < 250 µm), the iron-based process produced net a reduction in color and total organic carbon of about 95% and 70%, respectively. The process was also evaluated for the degradation of textile effluent. The studied process showed good characteristics, which can make it an effective alternative for polluted aquatic system remediation.

The identification and description of signal transduction molecules and mechanisms are essential to elucidate Schistosoma mansoni host-parasite interactions and parasite biology. This mini review focuses on recent advancements in the study of signalling molecules and transduction mechanisms in S. mansoni, drawing special attention to the recently identified and characterised protein tyrosine kinases of S. mansoni.

Anthropogenic pollution of groundwater and surface water has become a very serious environmental problem around the world. A wide range of toxic pollutants is recalcitrant to the conventional treatment methods, thus there is much interest in the development of more efficient remediation processes. Degradation of organic pollutants by zero-valent iron is one of the most promising approaches for water treatment, mainly because it is of low cost, easy to obtain and effective. After a general introduction to water pollution and current treatments, this work highlights the advances, applications and future trends of water remediation by zero-valent iron. Special attention is given to degradation of organochloride and nitroaromatic compounds, which are commonly found in textile and paper mill effluents.

Tióis de cadeias carbônicas com tamanhos diferentes e contendo grupo terminal COOH foram usados para formar monocamadas auto-organizadas sobre a superfície de eletrodos de ouro. A transferência de elétrons do par Fe(CN)6(3-/4-) para o eletrodo foi estudada em diferentes pH usando-se as técnicas de voltametria cíclica (CV) e de espectroscopia de impedância eletroquímica (EIS). Mudanças no pH da solução resultaram em variações na carga do grupo terminal das monocamadas auto-organizadas e, conseqüentemente, em alterações na interação eletrostática da SAM com as espécies eletroativas em solução.

Thiols with different alkyl chain length and containing COOH terminal group were self-assembled on gold electrodes. The electron transfer of Fe(CN)6(3-/4-) couple to the electrode was studied at different pH by means cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). Changes in solution pH resulted in the charge variation of the self-assembled monolayer (SAM) terminal group and, consequently, the electrostatic interaction of SAM with the electroactive species in the solution.

Self-assembled monolayers (SAMs) modified electrodes exhibit unique behavior that can greatly benefit electrochemical sensing. This brief review highlights the applications of SAM modified electrodes in electroanalytical chemistry. After a general introduction, which includes the approaches for SAM development, different electrochemical systems for detecting inorganic and organic species are described and discussed. Special attention to the coupling of biological sensing element to the SAM is given, which can selectively recognize the analyte. Future prospects are also evaluated.

A abordagem mais promissora para o desenvolvimento de biossensores eletroquímicos é a busca da comunicação elétrica direta entre as biomoléculas e a superfície do eletrodo. Esta revisão apresenta as principais abordagens, estratégias e avanços no desenvolvimento de biossensores eletroquímicos de terceira geração. Os temas discutidos englobam uma breve descrição sobre os fundamentos do fenômeno de transferência de elétrons e sobre o desenvolvimento de biossensores amperométricos (diferentes tipos e novas técnicas de imobilização orientada de enzimas). Um enfoque especial foi dado para as enzimas e proteínas redox capazes de eletrocatalisar reações via transferência direta de elétrons. Também foram apresentadas e discutidas as aplicações analíticas e tendências futuras dos biossensores de terceira geração.

The most promising approach for the development of electrochemical biosensors is to establish a direct electrical communication between the biomolecules and the electrode surface. This review focuses on advances, directions and strategies in the development of third generation electrochemical biosensors. Subjects covered include a brief description of the fundamentals of the electron transfer phenomenon and amperometric biosensor development (different types and new oriented enzyme immobilization techniques). Special attention is given to different redox enzymes and proteins capable of electrocatalyzing reactions via direct electron transfer. The analytical applications and future trends for third generation biosensors are also presented and discussed.

Desenvolveu-se um método de análise em fluxo para a determinação contínua de compostos fenólicos em matrizes ambientais, usando-se uma membrana de diálise para amostragem e biossensores a base de lacase e tirosinase para a detecção destes compostos. A resposta dos biossensores frente a diferentes compostos fenólicos foi investigada. O biossensor a base de lacase mostrou uma alta sensibilidade para guaiacol e cloroguaiacol, enquanto que o biossensor de tirosinase foi mais sensível para fenol e clorofenol. Ambos os biossensores apresentaram respostas seletivas para concentrações destes compostos em níveis micromolares. Limites de detecção de 1,1 x 10-7 mol L-1 para guaiacol e de 1,9 x 10-7 mol L-1 para cloroguaiacol foram obtidos usando-se o biossensor a base de lacase. Empregando-se o biossensor a base de tirosinase obteve-se limites de detecção de 1,5 x 10-7 mol L-1 para fenol e de 9,0 x 10-8 mol L-1 para clorofenol. O método de análise em fluxo proposto apresentou um faixa linear de trabalho entre 1,0 mimol L-1 e 100,0 mimol L-1, nas condições operacionais otimizadas dos biossensores (biossensor a base de lacase: pH 5,0 e potencial de trabalho 0 mV vs Ag/AgCl; biossensor a base de tirosinase: pH 5,0 e potencial de trabalho 50 mV vs Ag/AgCl). Uma amostra real de efluente papeleiro foi analisada pelo sistema proposto e pelo método colorimétrico de referência e os resultados discutidos.

A flow system method for continuous determination of phenolic compounds in environmental matrices was employed using a dialysis membrane sampler and laccase- and tyrosinase-based biosensors as detector. The biosensors response to different phenolic compounds was investigated. The laccase-based biosensor showed high sensitivity to guaiacol and chloroguaiacol, while the tyrosinase-based biosensor was more sensitive to phenol and chlorophenol. Both of the biosensors presented highly selective measurements of micromolar concentration of these compounds. Detection limits around 1.1 x 10-7 mol L-1 for guaiacol and 1.9 x 10-7 mol L-1 for chloroguaiacol could be estimated for the laccase-based biosensor. Using the tyrosinase-based biosensor detection limits of 1.5 x 10-7 mol L-1 for phenol and 9.0 x 10-8 mol L-1 for chlorophenol were observed. The proposed flow method presented a linear response range between 1.0 mumol L-1 and 100.0 mumol L-1, in the optimized operational conditions (laccase-based biosensor: pH 5.0 and 0 mV vs Ag/AgCl as working potential; tyrosinase-based biosensor: pH 5.5 and 50 mV vs Ag/AgCl as working potential). Real paper mill effluent sample was analyzed by this system and by the reference colorimetric method and the results were discussed.