15 research outputs found

    The Use of HRP in Decolorization of Reactive Dyes and Toxicological Evaluation of Their Products

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    This work studied the potential use of horseradish peroxidase (HRP) in the decolorization of the following textile dyes: Drimarene Blue X-3LR (DMBLR), Drimarene Blue X-BLN (DMBBLN), Drimarene Rubinol X-3LR (DMR), and Drimarene Blue CL-R (RBBR). Dyes were individually tested in the reaction media containing 120 mg·L−1, considering the following parameters: temperature (20–45°C), H2O2 concentration (0–4.44 mmol·L−1), and reaction time (5 minutes, 1 and 24 h). The following conditions: 35°C, 0.55 mmol·L−1, and 1h, provided the best set of results of color removal for DMBLR (99%), DMBBLN (77%), DMR (94%), and RBBR (97%). It should be mentioned that only 5 minutes of reaction was enough to obtain 96% of decolorization for DMBLR and RBBR. After the decolorization reactions of DMBLR, DMR, and RBBR, it was possible to observe the reduction of Artemia salina mortality and the no significant increase in toxicity for the products generated from DMBBLN

    The Protagonism of Biocatalysis in Green Chemistry and Its Environmental Benefits

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    The establishment of a bioeconomy era requires not only a change of production pattern, but also a deep modernization of the production processes through the implementation of novel methodologies in current industrial units, where waste materials and byproducts can be utilized as starting materials in the production of commodities such as biofuels and other high added value chemicals. The utilization of renewable raw resources and residues from the agro-industries, and their exploitation through various uses and applications through technologies, particularly solid-state fermentation (SSF), are the main focus of this review. The advocacy for biocatalysis in green chemistry and the environmental benefits of bioproduction are very clear, although this kind of industrial process is still an exception and not the rule. Potential and industrial products, such as biocatalysts, animal feed, fermentation medium, biofuels (biodiesel, lignocelulose ethanol, CH4, and H2), pharmaceuticals and chemicals are dealt with in this paper. The focus is the utilization of renewable resources and the important role of enzymatic process to support a sustainable green chemical industry.The authors are grateful to FAPERJ, CNPq, PETROBRAS, FINEP, PRH-ANP (all Brazilian), and MINECO (Spain) for financial support. We acknowledge support by the CSIC Open Access Publication Initiative through its Unit of Information Resources for Research (URICI)

    Comparação interlaboratorial para análise de dureza total e cloreto em água

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    Interlaboratorial comparison of the determination of hardness and chloride in water had been performed by 38 and 37 laboratories, respectively. In all cases the participating laboratories used its routine methods. Homogeneity and stability testing were performed on the samples sent to the laboratories. The codified results are graphically reported and compared to assigned value, determined by the consensus of the laboratories. Satisfactory results were obtained for 71 and 73% of the laboratories, considering hardness and chloride determination, respectively

    Simplified Method to Optimize Enzymatic Esters Syntheses in Solvent-Free Systems: Validation Using Literature and Experimental Data

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    The adoption of biocatalysis in solvent-free systems is an alternative to establish a greener esters production. An interesting correlation between the acid:alcohol molar ratio and biocatalyst (immobilized lipase) loading in the optimization of ester syntheses in solvent-free systems had been observed and explored. A simple mathematical tool named Substrate-Enzyme Relation (SER) has been developed, indicating a range of reaction conditions that resulted in high conversions. Here, SER utility has been validated using data from the literature and experimental assays, totalizing 39 different examples of solvent-free enzymatic esterifications. We found a good correlation between the SER trends and reaction conditions that promoted high conversions on the syntheses of short, mid, or long-chain esters. Moreover, the predictions obtained with SER are coherent with thermodynamic and kinetics aspects of enzymatic esterification in solvent-free systems. SER is an easy-to-handle tool to predict the reaction behavior, allowing obtaining optimum reaction conditions with a reduced number of experiments, including the adoption of reduced biocatalysts loadings

    Optimized atrazine degradation by Pleurotus ostreatus INCQS 40310: an alternative for impact reduction of herbicides used in sugarcane crops

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    Submitted by Alexandre Sousa ([email protected]) on 2016-08-02T17:44:51Z No. of bitstreams: 1 J_Microb_Biochem_Technol_S12-006.pdf: 1943299 bytes, checksum: a00c7d9cf985dde3762ab7b885ab8ef0 (MD5)Approved for entry into archive by Alexandre Sousa ([email protected]) on 2016-08-02T18:01:36Z (GMT) No. of bitstreams: 1 J_Microb_Biochem_Technol_S12-006.pdf: 1943299 bytes, checksum: a00c7d9cf985dde3762ab7b885ab8ef0 (MD5)Made available in DSpace on 2016-08-02T18:01:36Z (GMT). No. of bitstreams: 1 J_Microb_Biochem_Technol_S12-006.pdf: 1943299 bytes, checksum: a00c7d9cf985dde3762ab7b885ab8ef0 (MD5) Previous issue date: 2013Instituto Nacional de Tecnologia. Rio de Janeiro, RJ, Brasil.Universidade Federal do Rio de Janeiro. Instituto de Química. Rio de Janeiro, RJ, Brasil.Universidade Federal de Juiz de Fora. Departamento de Química. Rio de Janeiro, RJ, Brasil.Fundação Oswaldo Cruz. Instituto Nacional de Controle de Qualidade em Saúde. Programa de Pós-Graduação em Vigilância Sanitária. Rio de Janeiro, RJ, Brasil.Instituto Nacional de Tecnologia. Rio de Janeiro, RJ, Brasil.The herbicide atrazine (2-chloro-4-ethylamine-6-isopropylamine-s-triazine) is extensively used for weed control in sugarcane crops. The application of fungi for the biodegradation of xenobiotics has been studied with promising results. Therefore, atrazine degradation mediated by Pleurotus ostreatusINCQS 40310 was evaluated, and the involvement of ligninolytic enzymes along with the degradation process was also investigated. To promote high degradation percentages and rates, a fractional factorial experimental design was first used to determine the most significant medium components for atrazine degradation. This strategy improved atrazine degradation from 39.0% to 71.0% after 15 days, with the formation of different metabolites. Afterward, a 32 full factorial design was performed using the variables selected in the first part of this study. The salts FeSO4and MnSO4showed significant influence in the percentages and the rates of atrazine degradation. The medium optimization resulted in 90.3% and 94.5% of atrazine degradation after 10 days and 15 days, respectively. Although laccase activity was measured during the degradation process, it was not possible to correlate laccase activity with atrazine degradation. The results demonstrated the efficiency of P. Ostreatus INCQS 40310 for atrazine degradation, thus demonstrating the potential of this fungus as a bioremediation agent

    Technical–Economic Assessment—The Missing Piece for Increasing the Attractiveness of Applied Biocatalysis in Ester Syntheses?

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    Although the current literature describes significant advances in biocatalytic ester syntheses, few industrial plants worldwide are currently producing esters using biocatalysts. Green and sustainable esters can be obtained via a biocatalytic route, including some operational advantages over conventional syntheses. An analysis of the literature revealed that most articles neglect or describe the economic issues generically, without quantitative information. Scaling-up studies are also scarce in this field. The main disadvantage of biocatalysis using immobilized lipases—their cost—has not been studied at the same level of depth as other technical aspects. This gap in the literature is less intense in enzymatic biodiesel production studies and, despite the lack of a strict correlation, enzymatic biodiesel commercial plants are relatively more common. Preliminary techno-economic assessments are crucial to identify and circumvent the economic drawbacks of biocatalytic ester syntheses, opening the way to broader application of this technology in a large-scale context
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