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1.
Artigo em Inglês | MEDLINE | ID: mdl-38558334

RESUMO

Lipases represent versatile biocatalysts extensively employed in transesterification reactions for ester production. Ethyl oleate holds significance in biodiesel production, serving as a sustainable alternative to petroleum-derived diesel. In this study, our goal was to prospect lipase and assess its efficacy as a biocatalyst for ethyl oleate synthesis. For quantitative analysis, a base medium supplemented with Rhodamine B, olive oil, and Tween 80 was used. Solid-state fermentation utilized crambe seeds of varying particle sizes and humidity levels as substrates. In the synthesis of ethyl oleate, molar ratios of 1:3, 1:6, and 1:9, along with a total enzymatic activity of 60 U in n-heptane, were utilized at temperatures of 30 °C, 37 °C, and 44 °C. Reactions were conducted in a shaker at 200 rpm for 60 min. As a result, we first identified Penicillium polonicum and employed the method of solid-state fermentation using crambe seeds as a substrate to produce lipase. Our findings revealed heightened lipolytic activity (22.5 Ug-1) after 96 h of fermentation using crambe cake as the substrate. Optimal results were achieved with crambe seeds at a granulometry of 0.6 mm and a fermentation medium humidity of 60%. Additionally, electron microscopy suggested the immobilization of lipase in the substrate, enabling enzyme reuse for up to 4 cycles with 100% enzymatic activity. Subsequently, we conducted applicability tests of biocatalysts for ethyl oleate synthesis, optimizing parameters such as the acid/alcohol molar ratio, temperature, and reaction time. We attained 100% conversion within 30 min at 37 °C, and our results indicated that the molar ratio proportion did not significantly influence the outcome. These findings provide a methodological alternative for the utilization of biocatalysts in ethyl oleate synthesis.

2.
Molecules ; 28(3)2023 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-36770696

RESUMO

Caryocar brasiliense Cambess (pequi) is the fruit of the pequizeiro tree found in the Brazilian Cerrado (savanna). Supercritical fluids have been used to effectively extract bioactive chemicals. In light of the paucity of research on the supercritical extraction of pequi, in this study, experimental tests were conducted on the extraction of pequi almond oil using supercritical CO2; the optimal extraction conditions were determined, and the fatty acids and active compounds in the oil were characterized. The experiments were conducted using the Box-Behnken experimental design of a three-variable system: pressure (15, 20, and 25 MPa), temperature (303.15, 318.15, and 333.15 K), and flow rate (2, 3, and 5 g.min-1). The optimal extraction conditions were 318.15 K, 25 MPa, and 5.0 g.min-1, which yielded 27.6 wt% of oil. The experimental kinetic curves were described using a second-order quadratic model (based on the Sovová model), which demonstrated a satisfactory correspondence with the kinetic curves. Significant amounts of squalene, stigmasterol, oleic fatty acids, and palmitic fatty acids were detected in pequi almond oil.

3.
Environ Sci Pollut Res Int ; 29(42): 64192-64204, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35471761

RESUMO

This study refers to the development of hybrid briquettes using centrifuged sludge from the wastewater treatment of poultry and sawdust from furniture industry. The aim was to evaluate the performance of briquettes as a source of thermal energy, mitigating the risks of the current elimination and reducing the operational costs of their destination. To know the oxidizing characteristics of the briquettes and their mechanical resistance, superior calorific power, ash content, volatile materials, fixed carbon, and resistance to axial compression were evaluated. Thermogravimetric and differential exploratory calorimetry analyses were performed. Statistical treatments were carried out to verify the most significant factors to produce briquettes, the best proportions of the raw materials, and to evaluate whether there is interference from moisture and glue flour used as a binder. The best condition of the sludge-sawdust mixture was 15% and 85%, respectively, with 6.0% moisture. The best-case treatment had 23.82-MPa mechanical resistance, a calorific value of 17.20 MJ kg-1, and a density of 1374.15 kg m-3.


Assuntos
Matadouros , Esgotos , Animais , Biomassa , Carbono , Aves Domésticas
4.
Environ Sci Pollut Res Int ; 29(30): 45221-45229, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35146605

RESUMO

The main goal of this study was to assess alternatives to the current challenges on environmental quality and circular economy. The former is here addressed by the treatment of radioactively contaminated solutions, and the latter by using abundant and low-cost biomass. In this paper, we examine the biosorption of hexavalent uranium (U(VI)) in a batch system using the macrophytes Limnobium laevigatum and Azolla sp. by three operational parameters: biomass dose, metal ion concentration, and contact time. Simulated solutions were firstly addressed with two biomasses, followed by studies with real liquid organic radioactive waste (LORW) with Azolla sp. The batch experiments were carried out by mixing 0.20 g biomass in 10 mL of the prepared solution or LORW. The total contact time employed for the determination of the equilibrium times was 240 min, and the initial U(VI) concentration was 0.63 mmol L-1. The equilibrium times were 15 min for L. laevigatum and 30 min for Azolla sp. respectively. A wide range of initial U(VI) concentrations (0.25-36 mmol L-1) was then used to assess the adsorption capacity of each macrophyte. Isotherm models validated the adsorption performance of the biosorption process. Azolla sp. presented a much higher U(VI) uptake (0.474 mmol g-1) compared to L. laevigatum (0.026 mmol g-1). When in contact with LORW, Azolla sp. removed much less uranium, indicating an adsorption capacity of 0.010 mmol g-1. In conclusion, both biomasses, especially Azolla sp., can be used in the treatment of uranium-contaminated solutions.


Assuntos
Gleiquênias , Hydrocharitaceae , Urânio , Poluentes Radioativos da Água , Adsorção , Biomassa , Concentração de Íons de Hidrogênio , Cinética , Soluções , Água
5.
J Infect Dev Ctries ; 15(2): 270-279, 2021 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-33690211

RESUMO

INTRODUCTION: Trypanosoma cruzi is the agent of Chagas' disease and affects approximately 6-8 million people worldwide. The search for new anti-T. cruzi drugs are relevant because only two drugs exist actually. The objective of this study was to investigate the effect of the extracts from the seeds of Lonchocarpus cultratus on T. cruzi, its cytotoxicity as well as to elucidate its chemical profile. METHODOLOGY: The characterization of the extracts was done using 1H-RMN. T. cruzi forms were treated with increasing concentrations of the extracts and after, the percentage of inhibition and IC50 or LC50 were calculated. Murine peritoneal macrophages were treated with different concentrations of the extracts to evaluate the cellular viability. The hemotoxicity was accessed by verifying the levels of hemolysis caused by the extracts on human red blood cells. RESULTS: Chalcones isocordoin and lonchocarpin were detected in the dichloromethane extract, and chalcone lonchocarpin was detected in the hexane extract. The dichloromethane extract showed higher activity against all the forms of T. cruzi compared to the other two extracts, but the hexane showed the best selectivity index. The cytotoxicity observed in murine macrophages was confirmed in human erythrocytes, with dichloromethane extract having the highest toxicity. The methanolic extract showed the lowest anti-T. cruzi activity but was nontoxic to peritoneal murine macrophages and red blood cells. CONCLUSIONS: L. cultratus extracts have the potential to be explored for the development of new anti-trypanosomal drugs. This study was the first to demonstrate the action of extracts from the genus Lonchocarpus on infecting forms of T. cruzi.


Assuntos
Fabaceae/química , Macrófagos Peritoneais/parasitologia , Extratos Vegetais/farmacologia , Sementes/química , Trypanosoma cruzi/efeitos dos fármacos , Animais , Doença de Chagas/tratamento farmacológico , Fabaceae/classificação , Humanos , Concentração Inibidora 50 , Macrófagos Peritoneais/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos BALB C
6.
Saudi J Biol Sci ; 28(1): 99-108, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33424286

RESUMO

Trypanosoma cruzi is the agent of Chagas disease, an infection that affects around 8 million people worldwide. The search for new anti-T. cruzi drugs are relevant, mainly because the treatment of this disease is limited to two drugs. The objective of this study was to investigate the trypanocidal and cytotoxic activity and elucidate the chemical profile of extracts from the roots of the Lonchocarpus cultratus. Roots from L. cultratus were submitted to successive extractions with hexane, dichloromethane, and methanol, resulting in LCH, LCD, and LCM extracts, respectively. Characterization of extracts was done using 1H-RMN, 13C-RMN, CC and TLC. Treatment of T. cruzi forms (epimastigotes, trypomastigotes, and amastigotes) with crescent concentrations of LCH, LCD, and LCM was done for 72, 48, and 48 h, respectively. After this, the percentage of inhibition and IC50/LC50 were calculated. Benznidazole was used as a positive control. Murine macrophages were treated with different concentrations of both extracts for 48 h, and after, the cellular viability was determined by the MTT method and CC50 was calculated. The chalcones derricin and lonchocarpine were identified in the hexane extract, and for the first time in the genus Lonchocarpus, the presence of a dihydrolonchocarpine derivative was observed. Other chalcones such as isocordoin and erioschalcone B were detected in the dichloromethane extract. The dichloromethane extract showed higher activity against all tested forms of T. cruzi than the other two extracts, with IC50 values of 10.98, 2.42, and 0.83 µg/mL, respectively; these values are very close to those of benznidazole. Although the dichloromethane extract presented a cytotoxic effect against mammalian cells, it showed selectivity against amastigotes. The methanolic extract showed the lowest anti-T. cruzi activity but was non-toxic to peritoneal murine macrophages. Thus, the genus Lonchocarpus had demonstrated in the past action against epimastigotes forms of T. cruzi but is the first time that the activity against infective forms is showed, which leading to further studies with in vivo tests.

7.
Environ Sci Pollut Res Int ; 27(29): 36651-36663, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32564321

RESUMO

Rice and coffee husks (raw and chemically activated) are examined as potential biosorption materials regarding their capacity to remove U (total), 241Am, and 137Cs. The physical parameters evaluated were the morphological characteristics of the biomass, real and apparent density, and surface area. Contact times for the batch experiments were 0.5, 1, 2, and 4 h, and the concentrations tested ranged between 10% of the total concentration and the radioactive waste itself without any dilution. The results were evaluated by experimental sorption capacity, ternary isotherm, and kinetics models. The kinetics results showed that equilibrium was reached after 2 h for all biomass. Raw coffee husk showed the best adsorption results in terms of maximum capacity (qmax) for all three radionuclides, which were 1.96, 39.4 × 10-6, and 46.6 × 10-9 mg g-1 for U, Am, and Cs, respectively. The biosorption process for the raw and activated rice husks was best represented by the Langmuir ternary isotherm model with two sites. For the coffee husk, in the raw and activated states, the biosorption process was best described by the modified Jain and Snoeyink ternary model. These results suggest that biosorption with these biomaterials can be applied in the treatment of liquid organic radioactive waste containing mainly uranium and americium.


Assuntos
Oryza , Resíduos Radioativos , Poluentes Químicos da Água , Adsorção , Biomassa , Radioisótopos de Césio , Café , Concentração de Íons de Hidrogênio , Cinética
8.
J Photochem Photobiol B ; 203: 111763, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31931382

RESUMO

Photodynamic therapy (PDT) is a clinical modality that allows the destruction of tumor cells and microorganisms by reactive oxygen species, formed by the combination of photosensitizer (PS), molecular oxygen and adequate wavelength light. This research, through a clean methodology that involves pressurized liquids extraction (PLE), obtained a highly antimicrobial extract of Tetragonia tetragonoides, which rich in chlorophylls as photosensitizers. The Chlorophylls-based extract (Cbe-PLE) presented pharmacological safety, through the maintenance of cellular viability. In addition, Cbe-PLE showed great efficacy against Staphylococcus aureus, with severe dose-dependent damage to the cell wall of the pathogen. The obtained product has a high potential for the development of photostimulated phytotherapic formulations for clinical applications in localized infections, as a complementary therapeutic alternative to antibiotics.


Assuntos
Aizoaceae/química , Extratos Vegetais/química , Aizoaceae/metabolismo , Animais , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Clorofila/química , Clorofila/farmacologia , Luz , Camundongos , Testes de Sensibilidade Microbiana , Nanoestruturas/química , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/farmacologia , Folhas de Planta/química , Folhas de Planta/metabolismo , Caules de Planta/química , Caules de Planta/metabolismo , Staphylococcus aureus/efeitos dos fármacos
9.
J Environ Radioact ; 203: 179-186, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30925263

RESUMO

Biosorption-based technologies have been proposed for the removal of radionuclides from radioactive liquid waste containing organic compounds. Nevertheless, pytoremediation potential of uranium (U) by nonliving aquatic macrophytes Lemna sp. and Pistia stratiotes has not been previously addressed. In this study, uranium biosorption capacity by Pistia stratiotes and Lemna sp. was evaluated by equilibrium and kinetics experiments. The biomasses were added to synthetic and real waste solutions. The assays were tested in polypropylene vials containing 10 mL of uranium nitrate solution and 0.20 g of biomass. Solutions ranging from 0.25 to 84.03 mmol l-1 were employed for the assessment of uranium concentration in each macrophyte. The equilibrium time was 1 h for both macrophytes. Lemna sp. achieved the highest sorption capacity with the use of the synthetic solution, which was 0.68 mmol g-1 for the macrophyte. Since Lemna sp. exhibit a much higher adsorption capacity, only this biomass was exposed to the actual waste solution, being able to adsorb 9.24 × 10-3 mmol g-1 U (total). The results show that these materials are potentially applicable to the treatment of liquid radioactive waste.


Assuntos
Araceae/metabolismo , Biodegradação Ambiental , Urânio/metabolismo , Poluentes Radioativos da Água/metabolismo , Adsorção
10.
Environ Sci Pollut Res Int ; 24(11): 10778-10785, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28290084

RESUMO

This study evaluated the feasibility of production of briquettes using fine charcoal, sewage sludge, and mixtures thereof for use in energy production. The briquettes of 7-8 cm diameter and 20 cm length were produced in the conical press extruder type, mixing sewage sludge to charcoal fines in different ratios: 0:100, 25:75, 50:50, 75:25, and 100:0, with the addition of a binder (glue flour) in a ratio of 8 mass% prepared for briquetting. After air drying (temperatures between 24 and 30°C) for 48 h, the mechanical, thermal, and morphological characterizations were performed. The morphological properties of the briquettes were evaluated by scanning electron microscopy (SEM) and Fourier transform infrared (FTIR) spectroscopy. The briquettes produced had mechanical strength, with values between 210 and 420 kgf, and densities between 0.75 and 0.91 g cm-3. The calorific value of briquettes was in the range from 13.21 to 23.10 MJ kg-1, in which there was an increase with the increase of concentration of charcoal fines in the mixture. Thermogravimetric analysis showed mass losses that occurred in the temperature range between 150 and 740 °C. The results of the mechanical and thermal properties showed the feasibility of using fine charcoal briquettes from sewage sludge as well as mixtures thereof, for the production of energy. The fine charcoal briquette was the one with the highest calorific value, but not showed the highest resistance to mechanical shock.


Assuntos
Carvão Vegetal/química , Esgotos/química , Temperatura
12.
Parasitol Res ; 114(6): 2085-91, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25758585

RESUMO

Pediculosis is an infestation of the scalp caused by Pediculus humanus capitis, known as lice, which affects thousands of people throughout the world. Disease control is achieved by topical insecticides, whose indiscriminate use has led to the emergence of resistant populations of lice. Melia azedarach L. (Meliaceae) is an Asian tree that is found in Brazil, where it is popularly known as cinnamon or santa-bárbara. This study aimed to evaluate a pediculicidal treatment, made from a hydroethanolic extract of M. azedarach, and to study the effect of extraction solvents (ethanol and water) on insect mortality. The chemical composition of crude extract was studied by gas chromatography, identifying 32 methyl esters of fatty acids, with esters of heneicosanoic, palmitic, and arachidic acids present in greatest abundance. The (1)H and (13)C nuclear magnetic resonance (NMR) spectra suggested the presence of flavonoids and terpenes. Quercetin-3-O-ß-D-glucopyranoside (1) and quercetin-3-O-ß-D-glucopyranosyl-(1 → 6)-O-ß-D-glucopyranoside (2) were isolated from the extract. The bioassay of pediculicidal activity shows that the M. azedarach extract had a pediculicidal activity, inducing the death of all lice faster than 1% permethrin, a topical insecticide commonly used to control lice.


Assuntos
Antiparasitários/farmacologia , Infestações por Piolhos/tratamento farmacológico , Melia azedarach/química , Pediculus/efeitos dos fármacos , Extratos Vegetais/farmacologia , Animais , Antiparasitários/química , Antiparasitários/isolamento & purificação , Bioensaio , Brasil , Etanol/farmacologia , Feminino , Humanos , Inseticidas/farmacologia , Pediculus/fisiologia , Permetrina/farmacologia , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação
13.
Arch Oral Biol ; 59(6): 639-44, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24747412

RESUMO

AIM: It is known that atherosclerosis begins in childhood, a behaviour towards oral health care and metabolic control, since an early age, is essential for patients with cardiovascular disease. The aim of this research was to evaluate the effectiveness of periodontal treatment full-mouth scaling and root planning (FMSRP), applied to children without systemic diseases, correlating with periodontal clinical and blood parameters (lipid profile and inflammatory markers). MATERIALS AND METHODS: The 29 patients were divided into two groups, group 1 (14) - scaling and rot planning (SRP), group 2 (15) - FMSRP and the follow-up was conducted among 180 days. RESULTS: The results showed a significant improvement in clinical periodontal parameters (p<0.05) in both groups. In the analyzed blood parameters there was a greater evidence, with a significant improvement (p<0.05), in total cholesterol (TC), triglycerides (TGs), fibrinogen (FGN), and interleukin-6 (IL-6) CONCLUSIONS: Thus, we suggest that both periodontal treatments were effective in children without any systemic diseases.


Assuntos
Biomarcadores/sangue , Raspagem Dentária , Lipídeos/sangue , Periodontite/sangue , Periodontite/terapia , Brasil/epidemiologia , Criança , Índice de Placa Dentária , Feminino , Humanos , Inflamação/sangue , Masculino , Perda da Inserção Periodontal/epidemiologia , Índice Periodontal , Periodontite/epidemiologia , Aplainamento Radicular
14.
Vasc Health Risk Manag ; 9: 703-9, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24250224

RESUMO

Due to the biological associations between periodontal and cardiovascular diseases, as well as the fact that atherosclerosis begins in childhood, behavior based on oral health care and metabolic control from an early age is essential for patients with cardiovascular disease. The aim of this research was to examine the effect of full-mouth scaling and root planing on the reduction of periodontal disease in children with congenital heart disease. In this study, treatments were related to clinical periodontal parameters and also to blood ones, such as lipid profile and inflammatory markers. The patients were divided into two groups: group 1 (n=17), scaling and root planing; and group 2 (n=16), full-mouth scaling and root planing. The results showed a significant improvement in clinical periodontal parameters (P<0.05) in both groups. Considering lipid parameters, total cholesterol, triglycerides, and very-low-density lipoprotein parameters showed significant improvement (P<0.05). There was also an improvement in C-reactive protein (ultrasensitive) in the group treated with scaling and root planing (P<0.05). Fibrinogen and interleukin-6 parameters improved (P<0.05) in both groups. We suggest that both periodontal treatments were effective in children with congenital heart disease, though neither demonstrated superiority.


Assuntos
Aterosclerose/prevenção & controle , Raspagem Dentária , Cardiopatias Congênitas/complicações , Mediadores da Inflamação/sangue , Lipídeos/sangue , Doenças Periodontais/terapia , Aplainamento Radicular , Fatores Etários , Aterosclerose/sangue , Aterosclerose/diagnóstico , Aterosclerose/imunologia , Biomarcadores/sangue , Brasil , Criança , Feminino , Cardiopatias Congênitas/sangue , Cardiopatias Congênitas/diagnóstico , Cardiopatias Congênitas/imunologia , Humanos , Masculino , Doenças Periodontais/sangue , Doenças Periodontais/complicações , Doenças Periodontais/diagnóstico , Doenças Periodontais/imunologia , Estudos Prospectivos , Medição de Risco , Fatores de Risco , Resultado do Tratamento
15.
Molecules ; 18(6): 6215-29, 2013 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-23708233

RESUMO

Calophyllum brasiliense is a rich source of bioactive coumarins, xanthones and biflavonoids. The aim of the study was to compare the phenol contents and the antioxidant activity of C. brasiliense extracts obtained by conventional and supercritical fluid extraction (SFE) methods, as well as the quantification of crude extracts and (-)-mammea A/BB yields. Dichloromethane and hexane were used as solvents for the conventional extractions and SFE was developed using supercritical CO2; the kinetic curves were modeled using a second-order empirical model. The dichloromethane extract presented the best total yield, although it showed the lowest content of (-)-mammea A/BB. The concentration of the coumarin was considerably higher in extracts obtained by the supercritical fluid method and a higher antioxidant activity was assigned to extracts obtained by this technique. Concerning the total phenolic contents, both the dichloro-methane and the supercritical extractions produced satisfactory amounts. The SFE method proved to be more promising than conventional methods.


Assuntos
Antioxidantes/química , Antioxidantes/farmacologia , Calophyllum/química , Cromatografia com Fluido Supercrítico , Cumarínicos/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Cromatografia com Fluido Supercrítico/métodos , Modelos Teóricos , Fenóis/química , Fenóis/farmacologia
16.
J Hazard Mater ; 152(1): 366-72, 2008 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-17706867

RESUMO

A copper (II) ions biosorption by Sargassum sp. biomass was studied in a fixed bed column at 30 degrees C and pH 3.5. The experimental curves were obtained for the following feed concentrations -2.08, 4.16, 6.42 and 12.72mmol/L of the copper ions. The mathematical models developed by Thomas and Bohart-Adams were used for description of ions sorption process in the column. The models principle hypothesis is that the mass transfer controlling stage of the process is the adsorption kinetics between sorbate and adsorbent. The phenomena such as intraparticle diffusion, a mass transfer external resistance and axial dispersion effects were out of considerations. Some of the models parameters were experimentally determined (rho(B), epsilon, u(0), C(0)) and the others were evaluated on the bases of the experimental data (k(a1), k(a2)). The unique fitting parameter in all models was the adsorption kinetic constant. The identification procedure was based on the least square statistical method. Simulation results show that the models describe well a copper ions sorption process in a fixed bed column. The used models can be considered as useful tools for adsorption process design and optimization in fixed bed column by using algae biomass of Sargassum sp. as an adsorbent.


Assuntos
Cobre/isolamento & purificação , Eucariotos/metabolismo , Modelos Teóricos , Adsorção , Biomassa , Cinética
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