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Evaluation of the extraction of antioxidant compounds from buriti pulp (Mauritia flexuosa L.) by response surface methodology

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Heliyon 2025年第2期11卷 e41926页

作者： Nogueira, Gabriela Mota Cardoso, Flávia Aparecida Reitz Perdoncini, Márcia Regina Ferreira Geraldo da Silva, Marcos Vieira Rigobello, Eliane Sloboda Department of Food Engineering and Chemical Engineering Federal University of Technology–Paraná (UTFPR) Campo Mourão 87301-005 Brazil Post-Graduation Program of Food Technology (PPGTA) Federal University of Technology–Paraná (UTFPR) Campo Mourão 87301-005 Brazil Post-Graduation Program of Technological Innovations (PPGIT) Federal University of Technology–Paraná Campo Mourão 87301-005 Brazil Instituto Federal Farroupilha Campus Alegrete Alegrete 97555-000 Brazil

Buriti is a fruit rich in antioxidant compounds, and hydroalcoholic extracts were produced from its pulp to investigate the extraction conditions that result in the highest concentrations of bioactive compounds and maximum antioxidant capacity. The results showed considerable variation in the bioactive compound contents in the pulp: total phenolics (104.64–270.61 mg GAE 100 g-1), total flavonoids (17.74–60.46 mg EC 100 g⁻¹), and total carotenoids (1.30–3.92 mg kg⁻¹). The antioxidant capacity of the extracts, evaluated by DPPH, ABTS, and FRAP methods, ranged from 1.23 to 3.47 μmol ET g⁻¹, 6.34–15.86 μmol ET g⁻¹, and 4.74–11.95 μmol ET g⁻¹, respectively, highlighting the broad diversity of antioxidant activities present in the extracts. Data modeling generated statistically significant mathematical models and contour graphs, which allowed the identification of the optimal extraction conditions for the compounds. Total carotenoids were most effectively extracted with 20 % buriti pulp, intermediate ethanol concentrations, and temperatures around 70 °C. All other bioactive compounds were more efficiently extracted with 5 % buriti pulp, intermediate ethanol concentrations, and temperatures close to 30 °C. The results confirmed the efficiency of the extractions and highlighted the excellent antioxidant potential of buriti pulp. Additionally, the analysis of the optimal regions for extracting antioxidant compounds from the pulp can be applied in future studies to optimize the extraction process, providing a solid foundation for using this fruit in industrial processes, such as the production of functional ingredients. © 2025

关键词： Antioxidants Buriti Experimental design Extraction Pulp

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Transient CFD Simulation of Vortex Formation in a Stirred Multiphase Flow 6th

Transient CFD Simulation of Vortex Formation in a Stirred Mu...

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6th Multiphase Flow Journey, JEM 2021

作者： Nogueira, André Lourenço Department of Chemical Engineering and Post-Graduation Program in Process Engineering University of the Region of Joinville UNIVILLE Joinville89219-710 Brazil

ISBN: (纸本)9783030934552

The present study simulated the dynamic behavior of the water–air interface in a cylindrical tank stirred mechanically. CFD techniques were applied using the software ANSYS-Fluent. The Volume of Fluid (VOF) model with explicit formulation coupled to the κ - ω SST turbulence model was employed to numerically represent the transient displacement of the water–air interface starting from a situation of stagnated flow. An isothermal operation was considered for the case studied. A simple experimental apparatus composed of a glass vessel filled with dyed water and a mechanical stirrer with a pitched-bladed impeller was used to generate the experimental data of the interface position along the time. The model accuracy was evaluated at stirring rates of 300 and 400 RPM. According to the results, the geometric shape profile of the vortex at the pseudo-stationary state could be reasonably well reproduced by the model. However, the model could not generate accurate results regarding the transient behavior of the vortex formation. Additional strategies should be tested to enhance the model capability to reproduce the transient displacement of the water–air interface due to the rotational flow. © 2022, The Author(s), under exclusive license to Springer Nature Switzerland AG.

关键词： Computational fluid dynamics Stirred tank Two-phase interface

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Assessment of the Total Organic Carbon and Conductivity in Consecutive Dyeings with Reactive Dyestuffs Using Treated Effluent by UV/H202 Photocatalysis

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Journal of Chemistry and chemical engineering 2014年第2期8卷 139-144页

作者： Leite Adilson da SilvaI Barco Luiz Trindade Nelson Barros Araujo Mauricio de Campos Rosa Jorge Marcos Tambourgi Elias Basile Santana José Carlos Curvelo Chemical Textile Post Graduation Department College of Technology SENAI Antoine Skaf $6o Paulo 03008-020 Brazil Textile and Fashion Post Graduation Program S6o Paulo University S6o Paulo 03828-000 Brazil College of Chemical Engineering State University of Campinas Campinas 13083-852 Brazil Production Engineering Post Graduation Program Nove de Julho University Sao Paulo 05001-100 Brazil

The paper was monitored the conductivity （g.L＂l of NaCI）, the absorbances values （Abs） and the amount of TOC （total organic carbon）, before and after five consecutive dyeings made with reuse water, obtained from treated effluent by UV/H202 photocatalysis. All rates of decolorization were above 92%, the removal of total organic carbon was above 89% in all treatments and the economy of NaCI was from 3.10 in the first recipe, 3.17 in the second, 3.49 in the third, 3.79 in the fourth and 4.05 in the fifth recipe. The five dyeings compared with same dyeings made with deionized water presented a color deviation （AE＊） below 1. The conventional dyeings would consume 80 L/kg against 40 L/kg used in the dyeing process proposed in this study, representing a great economy of water, with no discharge of effluents.

关键词： Conductivity reactive dyestuffs reuse of water photocatalysis textile effluent.

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Synthesis of PMMA Nanoparticles Loaded with Geopropolis Extract from the Brazilian Stingless Bee Melipona quadrifasciata Lepeletier, 1836 by Miniemulsion Polymerization

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Macromolecular Symposia 2022年第1期406卷 2200046-2200046页

作者： da Silva, Thiago S. Nogueira, André L. Lafratta, Fernando H. Department of Chemical and Food Engineering Federal University of Santa Catarina – UFSC Florianópolis88040-900 Brazil Department of Chemical Engineering and Post-Graduation Program in Process Engineering University of the Region of Joinville – UNIVILLE Santa Catarina Joinville89219-710 Brazil Department of Mechanical Engineering Santa Catarina State University – UDESC Santa Catarina Joinville89219-710 Brazil

The present work aims to encapsulate the concentrated geopropolis extract from the Brazilian stingless bee Melipona quadrifasciata quadrifasciata Lepeletier, 1836 in poly(methyl methacrylate) (PMMA) nanoparticles produced by miniemulsion polymerization. The concentrated geopropolis extract is obtained by hydroalcoholic maceration and characterized by ultraviolet–visible spectrophotometry (UV–Vis) to quantify flavonoids and polyphenols in terms of quercetin (Q) and galic acid (GA), respectively. The PMMA-Propolis nanoparticles is characterized by size exclusion chromatography (SEC), transmission electron microscopy (TEM), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), UV–Vis and nuclear magnetic resonance (NMR1H). UV–Vis results of the geopropolis extract revealed an average flavonoid content of 22.51 mg Q g–1 and an average polyphenol content of 10.15 mg GA g–1. TEM images showed that the produced PMMA nanoparticles are spherical, and their average diameter reduced from 72.62 to 44.60 nm by increasing the propolis concentration from 0% to 40%. Additionally, the kinetic data reveal a reduction of the polymerization reaction rate as well as the average molecular weight when raising the propolis extract concentration in the reaction media. These results suggest that propolis extract may be used as a biocompatible and biodegradable co-stabilizer and chain transfer agent in miniemulsion polymerization reactions of vinyl monomers. © 2022 Wiley-VCH GmbH.

关键词： Thermogravimetric analysis

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The question of socio-environmental accountability in recycling of plastics in Rio de Janeiro

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Procedia Environmental Sciences 2011年 4卷 323-330页

作者： M.A.G. de Figueiredo A.C. Deorsola Estadual University of Rio de Janeiro Chemistry Institute Department of Industrial Operations and Projects Brazil Estadual University of Rio de Janeiro Chemistry Institute Post Graduation Program in Chemical Engineering (PGPEQ) Brazil

This study aimed to determine how the activities of recycling impact on health, safety and the environment also raising questions related to social accountability, especially on the compliance with regulatory standards, and the legislation on health, safety and the environment. A questionnaire was developed and was applied directly to a group of recyclers, all located in Rio de Janeiro, Brazil being three from the Polyethylene segment and one from ethylene polyterephthalate. It was found that only 24% of the items evaluated were complied with in their entirety, demonstrating a low rate of compliance with issues related to health, safety, environment and social accountability. Ultimately, this study shows that there is a need for greater attention by the government to create an infrastructure for training in order to permeate information on health, safety, environment and social accountability to the professionals who operate in this sector.

关键词： Recycling Plastic Health Safety Social Accountability

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Effect of Concentration and Residence Time of Joncryl■ADR4368 on Melt processability of Poly(3-hydroxybutyrate)

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Journal of Renewable Materials 2024年第12期12卷 2079-2094页

作者： Jéssica da Silva Chagas JoséElson Soares Filho Natália Fernanda Inocêncio Silva Marcelo Massayoshi Ueki Eliton Souto de Medeiros Renate Maria Ramos Wellen Mauricio Pinheiro de Oliveira Gelsoneide da Silva Gois Yêda Medeiros Bastos de Almeida Amélia S.F.Santos Post-Graduation Program in Materials Engineering(PPCEM) Federal University of Paraíba(UFPB)João PessoaPB 58051-900Brazil Laboratory of Materials and Biosystems(LAMAB) Federal University of Paraíba(UFPB)João PessoaPB 58051-900Brazil Department of Materials Engineering Federal University of Sergipe(UFS)Jardim Rosa ElzeSão CristóvãoSE 49100-000Brazil Institute of Science and Technology Federal University of São Paulo(UNIFESP)São Josédos CamposSP 12231-280Brazil Department of Chemical Engineering Federal University of Pernambuco(UFPE)Cidade UniversitáriaRecifePE 50670-901Brazil

Poly(3-hydroxybutyrate)(PHB)is a biothechnological and biodegradable thermoplastic polymer from the polyhydroxyalkanoates(PHAs)family,whose chain regularity,high molecular weight,and physical and mechanical properties comparable to polypropylene(PP)are characteristics that have made PHB a prominent commercial ***,its susceptibility to thermal degradation and hydrolysis has limited many *** address the challenges associated with processing,a random copolymer of 95.86 mol%3-hydroxybutyrate and 4.14 mol%3-hydroxyvalerate(referred as PHB)was compounded without(neat PHB)and with 0.25,0.5,1,and 1.5 wt%of chain extender(Joncryl■ADR 4368),consisting of multifunctional epoxy groups,and melt mixed in an internal mixer at 170℃,50 rpm,and residence times of 5,10,and 15 *** effect of chain extender concentration and residence time on the effectiveness of Joncryl■ADR 4368 to recover the pristine PHB properties were investigated through torque rheometry,melt flow index(MFI),differential scanning calorimetry(DSC),tensile testing,and thermogravimetric *** results indicated that an increase in residence time strongly influenced the prevalence of thermomechanical degradation reactions over chain extension reactions of PHB during processing in the molten *** residence times favored chain extension,while longer times favored chain *** trend led to no enhancement of PHB mechanical properties processed for 10 and 15 min,regardless of additive content *** flow index,thermogravimetric analysis and tensile strength exhibited an asymptotic behavior with the increase in additive concentration,exhibiting a noteworthy improvement in tensile strength and temperature at the highest rate of thermal degradation(TMAX),and a decrease in melt flow index of neat PHB with only 0.25 wt%of additive mixed for 5 *** results found in this work allow additional data for processing PHB by manipulating the ratios of multifunctional chain

关键词： PHB chain extender degradation epoxy groups viscosity

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Bo-derived waste neem to enriching reinforced hybrid composite for environmental remediation

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Chemosphere 2024年 350卷 141055页

作者： Anbuchezhiyan, Gnanasambandam Mubarak, Nabisab Mujawar Hussain Siddiqui, Muhammad Tahir Malafaia, Guilherme Abnisa, Faisal Department of Mechanical Engineering Saveetha School of Engineering Saveetha Institute of Medical and Technical Sciences Tamil Nadu Chennai602105 India Petroleum and Chemical Engineering Faculty of Engineering Universiti Teknologi Brunei Bandar Seri BegawanBE1410 Brunei Department of Chemistry School of Chemical Engineering and Physical Sciences Lovely Professional University Punjab Jalandhar India Department of Chemical and Materials Engineering Faculty of Engineering King Abdulaziz University Rabigh21911 Saudi Arabia School of Engineering RMIT University MelbourneVIC3001 Australia Post-Graduation Program in Ecology Conservation and Biodiversity Federal University of Uberlândia MG Uberlândia Brazil Laboratory of Toxicology Applied to the Environment Goiano Federal Institute – Urutaí Campus. Rodovia Geraldo Silva Nascimento 2 5 Km Zona Rural GO Urutaí Brazil Post-Graduation Program in Conservation of Cerrado Natural Resources Goiano Federal Institute Post-Graduation Program in Biotechnology and Biodiversity Federal University of Goiás GO Goiânia Brazil

The utilization of natural fibres often entails a lesser environmental impact when compared to synthetic fibres. Biodegradable natural fibres minimize waste and pollution, and promote sustainability, but their weaker bonds limit their resilience. These issues can be addressed by customizing the composite's mechanical properties with natural and synthetic fibres. In this study, hybrid composites were created using the hand layup method with a novel dissimilar layer arrangement of neem (N), sisal (S), and glass (G) fibre and analyze its mechanical and thermal properties. Experimental observation shows that the GN composite had a higher maximum ultimate tensile strength of 26 N/mm2 than the GS, GNS, and GSN composites. The GN composite had a percentage elongation of 6.33%, similar to the percentage elongation of the GS composite (6.833%), and it also had a higher ultimate shear strength of 50 MPa. The composite GS absorbed 6.6 J energy, higher than the composites GN, GNS, and GNS, which absorbed 6.1 J, 4.5 J, and 4.5 J, respectively. The fractured surface's SEM images were obtained and analyzed for failure. The results demonstrated that the hybridization was effective, and better properties can be obtained by combining neem, sisal, and glass fiber, and it can be used for other requirements, including strength, weight, cost, and ecological impact. © 2024 Elsevier Ltd

关键词： Glass

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Analysis of post-tanning chemicals and Reduction of Pollution Load in Wastewater 36

Analysis of Post-tanning Chemicals and Reduction of Pollutio...

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36th International Union of Leather Technologists and Chemists Societies Congress 2021, IULTCS 2021

作者： Hansen, Éverton de Aquim, Patrice Monteiro Gutterres, Mariliz Federal University of Rio Grande do Sul - UFRGS Post-Graduation Program of Chemical Engineering Laboratory for Leather and Environmental Studies -LACOURO Eng. Luiz Englert street RS Porto Alegre Brazil Feevale University Institute of Pure Sciences and Technology 2755 RS 239 Novo Hamburgo RS Brazil Centro Universitário Ritter dos Reis - UniRitter 555 Orfanotrófio RS Porto Alegre Brazil Universidade do Vale do Rio dos Sinos Chemical Engineering Department 950 Av. Unisinos RS São Leopoldo Brazil

The chemicals in post-tanning are partially retained by the leather, and the fractions remaining in the process are discharged with the wastewater. Current literature has an extensive number of studies characterizing tannery effluents. However, few studies have evaluated how groups of chemicals applied to the leather impact the quality of wastewater generated in the process. Thus, this study aims to evaluate and reduce the impact of chemicals used in the post-tanning process on the main quality parameters of the wastewater. The assessment and reduction of the pollution load of leather chemicals were carried out using a formulation from a Brazilian tannery as a case study. Results showed that retanning agents (natural and synthetic tannins) were responsible for high inorganic pollution load in the wastewater, and the synthetic tannins were more toxic than the natural ones. The fatliquoring agents were responsible for the highest chemical oxygen demand load in the wastewater and were the chemical group that presented the highest cytotoxicity. The fixing agent and the dye contributed to the inorganic pollution load of the wastewater, and the nitrogen load of the wastewater was mainly related to the neutralizing retanner and the dye. The adjustment of the chemicals supply showed depletion in the pollution load of wastewater. The obtained leather showed quality within the required specifications of the tannery, and the formulation cost was reduced by 24%. © 2021 XXXVI International Union of Leather Technologists and Chemists Societies Congress 2021, IULTCS 2021. All rights reserved.

关键词： Leather

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Short-Term Exposure of the Mayfly Larvae (Cloeon Dipterum, Ephemeroptera: Baetidae) to Sars-Cov-2-Derived Peptides and Other Emerging Pollutants: A New Threat for the Aquatic Environments

SSRN

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SSRN 2022年

作者： Freitas, Ítalo Nascimento Dourado, Amanda Vieira Araújo, Amanda Pereira da Costa da Silva Matos, Stênio Gonçalves de Souza, Sindoval Silva Luz, Thiarlen Marinho da Rodrigues, Aline Sueli de Lima Batista Guimarães, Abraão Tiago Nabisab Mujawar, Mubarak Rahman, Md Mostafizur Arias, Andrés Hugo Malafaia, Guilherme Laboratory of Toxicology Applied to the Environment Goiano Federal Institute Urutaí GO Brazil Post-Graduation Program in Conservation of Cerrado Natural Resources Goiano Federal Institute Urutaí GO Brazil Post-Graduation Program in Environmental Sciences Federal University of Goiás GO Goiânia Brazil Post-Graduation Program in Biotechnology and Biodiversity Federal University of Goiás GO Goiânia Brazil Petroleum and Chemical Engineering Faculty of Engineering Universiti Teknologi Brunei Bandar Seri Begawan BE1410 Brunei Laboratory of Environmental Health and Ecotoxicology Department of Environmental Sciences Jahangirnagar University Dhaka1342 Bangladesh CONICET Florida 8000 Complejo CCT CONICET Bahía Blanca Bahía Blanca Argentina Post-Graduation Program in Ecology Conservation and Biodiversity Federal University of Uberlândia MG Uberlândia Brazil

The input of SARS-CoV-2 or its fragments into freshwater ecosystems (via domestic or hospital sewage) has raised concerns about its possible impacts on aquatic organisms. Thus, using mayfly larvae [Cloeon dipterum (L.), Ephemeroptera: Baetidae] as a model system, we aimed to evaluate the possible effects of the combined short exposure of SARS-CoV-2-derived peptides (named PSPD-2001, PSPD-2002, and PSPD-2003 – at 266.2 ng/L) with multiple emerging pollutants at ambient concentrations. After six days of exposure, we observed higher mortality of larvae exposed to SARS-CoV-2-derived peptides (alone or in combination with the pollutant mix) and a lower-body condition index than those unexposed larvae. In the "PSPD" and "Mix+PSPD" groups, the activity of superoxide dismutase, catalase, DPPH radical scavenging activity, and the total thiol levels were also lower than in the "control" group. In addition, we evidenced the induction of nitrosative stress (inferred by increased nitrite production) and reduced acetylcholinesterase activity by SARS-CoV-2-derived peptides. On the other hand, malondialdehyde levels in larvae exposed to treatments were significantly lower than in unexposed larvae. The values of the integrated biomarker response index and the results of the principal component analysis (PCA) confirmed the similarity between the responses of animals exposed to SARS-CoV-2-derived peptides (alone and in combination with the pollutant mix). Although viral peptides did not intensify the effects of the pollutant mix, our study sheds light on the potential ecotoxicological risk associated with the spread of the new coronavirus in aquatic environments and therefore, recommends that this topic be explored in other organisms and different experimental contexts. © 2022, The Authors. All rights reserved.

关键词： Coronavirus

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Plant-Zno Nanoparticles Interaction: An Approach to Improve Guinea Grass (Panicum Maximum) Productivity and Evaluation of the Impacts of its Ingestion by Freshwater Teleost Fish

SSRN

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SSRN 2023年

作者： Gomes, Alex Rodrigues de Matos, Letícia Paiva Batista Guimarães, Abraão Tiago Freitas, Ítalo Nascimento da Luz, Thiarlen Marinho Silva, Abner Marcelino da Silva Matos, Stênio Gonçalves de Lima Rodrigues, Aline Sueli de Oliveira Ferreira, Raíssa Towfiqul Islam, Abu Reza Md. Rahman, Md. Mostafizur Ragavendran, Chinnasamy Kamaraj, Chinnaperumal Mubarak, Nabisab Mujawar Arias, Andrés Hugo Silva, Fabiano Guimarães Malafaia, Guilherme Laboratory of Toxicology Applied to the Environment Goiano Federal Institute GO Urutaí Brazil Post-Graduation Program in Ecology Conservation and Biodiversity Federal University of Uberlândia MG Uberlândia Brazil Post-Graduation Program in Agronomy Goiano Federal Institute Campus Rio Verde GO Brazil Post-Graduation Program in Conservation of Cerrado Natural Resources Goiano Federal Institute GO Urutaí Brazil Begum Rokeya University Department of Disaster Management Rangpur5404 Bangladesh Laboratory of Environmental Health and Ecotoxicology Department of Environmental Sciences Jahangirnagar University Dhaka1342 Bangladesh Chennai India Tamil Nadu Kattankulathur603203 India Petroleum and Chemical Engineering Faculty of Engineering Universiti Teknologi Brunei Bandar Seri Begawan Brunei DarussalamBE1410 Brunei Argentina Post-Graduation Program in Biotechnology and Biodiversity Federal University of Goiás GO Goiânia Brazil Brazil

We aimed to evaluate the possible effects of the application of ZnO NPs (in the substrate, at 100 and 500 mg/kg) in the cultivation of Panicum maximum (Guinea grass), using biometric, morphological, biochemical, and productivity biomarkers in addition to evaluating the uptake of Zn by the plants. Furthermore, we assessed the possible transfer of ZnO NPs from P. maximum leaves to zebrafish and their effects on the health of the animals. Plants cultivated in substrates enriched with ZnO NPs at 500 mg/kg showed a lower germination rate and affected germination and plant growth. However, P. maximum grown on substrate enriched with ZnO NPs (at 100 mg/kg) showed higher biomass and productivity, associated with higher Zn uptake, without inducing redox imbalance and nitrosative stress. PCA analysis and cluster analysis confirmed the differential performance of the crop in substrate containing ZnO NPs at 100 mg/kg. Zinc content in zebrafish was not associated with ingesting leaves of P. maximum in substrate containing ZnCl2 or ZnO NPs or with genotoxic, mutagenic, and biochemical effects. In conclusion, ZnO NPs (at 100 mg/kg) are promising in the cultivation of P. maximum, and their ingestion by zebrafish did not cause significant ecotoxicological effects from the evaluated biomarkers. © 2023, The Authors. All rights reserved.

关键词： II-VI semiconductors

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