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1.
Water Sci Technol ; 80(3): 426-436, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31596254

RESUMO

Thermal pre-flocculation to enable dispersed air flotation is an economical and ecofriendly technology for harvesting microalgae from water. However, the underlying mechanism and optimal conditions for this method remain unclear. In this study, Chlorella vulgaris (C. vulgaris) and Scenedesmus obliquus (S. obliquus) were harvested using a thermal flotation process. The surface structure and characteristics (morphology, electricity, and hydrophobicity) of the microalgae were analyzed using FT-IR (Fourier transform infrared spectroscopy), SEM (scanning electron microscopy), zeta potential, and a hydrophobic test. Further, response surface methodology (RSM) was used to optimize the flotation process. The hydrophobicity of S. obliquus exceeded that of C. vulgaris; as such, under the thermal pre-flocculation, S. obliquus (88.16%) was harvested more efficiently than C. vulgaris (47.16%). Thermal pre-flocculation denatured the lipids, carbohydrate, and proteins of microalgal cell surfaces. This resulted in a decrease in the electrostatic repulsion between the cells and air bubbles. The highest harvesting efficiency was 91.96% at 70 °C, 1,412 rpm, and 13.36 min. The results of this study demonstrate the potential for economic and ecofriendly harvesting of microalgae for biofuels and other bioproducts industries.


Assuntos
Chlorella vulgaris , Microalgas , Biocombustíveis , Biomassa , Floculação , Espectroscopia de Infravermelho com Transformada de Fourier
2.
Water Sci Technol ; 80(3): 587-596, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31596269

RESUMO

The aim of this study was to determine the removal of ciprofloxacin (CIP) by the electro-persulfate (EC-PS) process using aluminum (Al) electrodes. The effects of variables including pH, contact time, PS concentration, initial CIP concentration and current density on the removal efficiency of CIP were studied. In order to determine the mechanisms of the EC-PS process, the radical scavenger tests, as well as energy dispersive spectroscopy (EDS) and Fourier transform infrared spectroscopy (FT-IR) were performed on the sludge. The results showed that the PS process alone had no effect on the CIP removal, and the EC process alone could remove 25% of CIP after 160 min. However, the EC-PS process under the optimum conditions: pH of 7, time of 40 min, current density of 2.75 mA/cm2, CIP concentration of 20 mg/L, and PS concentration of 0.84 mM removed 90% of CIP. The effect of the EC-PS process on the actual hospital wastewater was 81% in optimal conditions. The kinetic study also showed that the second-order kinetic model was the most consistent. The oxidation process during the initial contact was dominant in the EC-PS process and, over time, the EC process was dominant for CIP removal.


Assuntos
Ciprofloxacino/análise , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Alumínio/química , Eletrodos , Espectroscopia de Infravermelho com Transformada de Fourier
3.
Ying Yong Sheng Tai Xue Bao ; 30(9): 3215-3223, 2019 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-31529897

RESUMO

The modified fly ash (MFA) was prepared through roasting the mixture of fly ash and NaOH/Ca(OH)2 at 250 ℃ for 1.5 h. The physicochemical properties of MFA were analyzed by scanning electron microscope (SEM), energy dispersive spectrometer (EDS), X-ray diffraction (XRD), surface area analyze (BET), and Fourier transform infrared spectroscopy (FTIR) techniques. Results from BET analysis showed that the BET of MFA was enlarged by 20.6 times compared with FA. Results from SEM analysis showed that the glass phase was dissolved, with a rough surface and porous structure. Results from FTIR analysis demonstrated that -OH played an important role in Cd2+ adsorption. Results from the static adsorption experiment revealed that the removal efficiency of Cd2+ reached 97.3% when 0.2 g MFA was applied while the concentration of Cd2+ was 100 mg·L-1, the solution pH was 7.0, the adsorption temperature was 25 ℃ and the adsorption time was 90 min. In addition, the coexisting cations (K+, Na+, Mg2+, and Ca2+) might inhibit Cd2+ adsorption. Among all the cations, Ca2+ showed a most significant inhibitory effect on the removal of Cd2+. Langmuir isotherm and the pseudo-second-order kinetic models could well describe the adsorption behavior of Cd2+ on MFA, with the maximum adsorption capacity of 55.77 mg·g-1. Meanwhile, thermodynamic studies showed that Cd2+ adsorption onto MFA was spontaneous and endothermic process. MFA had better adsorption capacity than FA and had certain application pro-spects in wastewater treatment.


Assuntos
Cádmio/química , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias , Poluentes Químicos da Água/química , Adsorção , Cinza de Carvão , Concentração de Íons de Hidrogênio , Cinética , Espectroscopia de Infravermelho com Transformada de Fourier
4.
Bioresour Technol ; 293: 122062, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31494436

RESUMO

The study aimed to evaluate biopolymer production using two bacterial strains, Acinetobacter junii BP25 and Aeromonas hydrophila ATCC 7966, and their co-culture. Batch experiments were evaluated using acetate and butyrate as carbon sources in feast and famine strategy. Feast phase was studied using carbon, nitrates and phosphate in the ratio of 100:8:1 and famine phase was limited with the phosphate and nitrates. Co-culture resulted in highest specific growth rate (0.30 h-1) in the feast phase and the famine phase accounted the maximum polyhydroxybutyrate (PHB) accumulation (2.46 g PHB/L), followed by Acinetobacter junii BP25 (0.25 h-1 and 1.82 g PHB/L) and Aeromonas hydrophila ATCC 7966 (0.17 h-1 and 1.12 g PHB/L). Fourier-transform infrared spectroscopy (FT-IR) and nuclear magnetic resonance spectroscopy (NMR) structural analysis confirmed as PHB. PHB production using the co-culture could be integrated with biohydrogen process using volatile fatty acids (VFA) as a carbon source in the biorefinery framework.


Assuntos
Acinetobacter , Butiratos , Aeromonas hydrophila , Reatores Biológicos , Técnicas de Cocultura , Hidroxibutiratos , Poliésteres , Espectroscopia de Infravermelho com Transformada de Fourier
5.
Int J Nanomedicine ; 14: 4741-4754, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31456635

RESUMO

Background: Ipomoea batatas (L.) Lam.(Ib) has high content of various beneficial nutrients which helps in improving and maintaining human health. It is well known as a functional food and also a valuable source of unique natural products. It contains various phenolic and flavonoid bioactive compounds. Methods: In this study, using the outer peel of two varieties of Ib : Korean red skin sweet potato and Korean pumpkin sweet potato, silver nanoparticles (AgNPs) were synthesized (termed Ib1-AgNps and Ib2-AgNps), respectively. Characterization of Ib1-AgNPs and Ib2-AgNPs was carried out through scanning electron microscopy, Fourier-transform infrared (FT-IR) spectroscopy, energy-dispersive X-ray analysis, X-ray powder diffraction and UV-Vis spectroscopy. Further, the bio-potential of the synthesized AgNPs was investigated by antidiabetic (α-glucosidase assay), antioxidant (free radical scavenging assays), antibacterial (disc diffusion method) and cytotoxicity assays (cell viability against HepG2 cells). Results: FT-IR spectroscopy revealed the contribution of bioactive compounds existing in Ib1 and Ib2 extracts, in the biosynthesis and equilibrium of the AgNPs. Although the Ib2-AgNPs had a higher atomic percentage of Ag in comparison with Ib1-AgNPs, in the antidiabetic assay, the inhibition percentage of α-glucosidase was higher for AgNPs of Ib1 than Ib2, at all three concentrations examined. From the cytotoxicity results, HepG2 cancer cells were more sensitive to the Ib1-AgNPs in comparison to the Ib2-AgNPs-treated HepG2 cells. The antioxidant prospective was higher in Ib2-AgNPs than Ib1-AgNPs. Moreover, the Ib2-AgNPs showed inhibitory action against all five tested pathogenic bacteria, producing an inhibition zone of 8.74-11.52 mm while Ib1-AgNPs had an inhibitory effect on four of them, with an 8.67-11.23 (mm) inhibition zone. Conclusions: Overall, the results concluded that the Ib2-AgNPs exhibited relatively higher functional activity than Ib1-AgNPs, which might be credited to the greater abundance of bioactive compounds existing in Ib2 extract that acted as reducing as well as capping agents in the synthesis of Ib2-AgNPs. Overall, the current study highlights a novel cost-effective and eco-friendly AgNPs synthesis using food waste peels with biocompatibility and could be potentially utilized in biomedical and pharmaceutical industries.


Assuntos
Antibacterianos/farmacologia , Antioxidantes/farmacologia , Ipomoea batatas/química , Nanopartículas Metálicas/química , Prata/farmacologia , Bactérias/efeitos dos fármacos , Morte Celular/efeitos dos fármacos , Células Hep G2 , Humanos , Hipoglicemiantes/farmacologia , Concentração Inibidora 50 , Nanopartículas Metálicas/ultraestrutura , Testes de Sensibilidade Microbiana , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X , alfa-Glucosidases/metabolismo
6.
Int J Nanomedicine ; 14: 4895-4909, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31456636

RESUMO

Introduction: Insulin is given by injection, because when administered orally, it would be destroyed by enzymes in the digestive system, hence only about 0.1% reaches blood circulation. The purpose of the present study was to use pH sensitive polyelectrolyte methyl methacrylate (MMA)/itaconic acid (IA) nanogels as carriers in an attempt to improve absorption of insulin administered orally. Methods: Insulin (Ins) was incorporated into the MMA/IA nanogels (NGs) using the polyelectrolyte complexation (PEC) method to form Ins/NGs-PEC. Several parameters, including Ins:NGs ratio, pH, incubation time and stirring rate were optimized during preparation of InsNGs-PEC. The prepared formulations were characterized in terms of particle size (PS), polydispersity index (PdI), zeta potential (ZP) and percent entrapment efficiency (% EE). Results: The optimized InF12 nanogels had a PS, PdI, ZP and %EE of 190.43 nm, 0.186, -16.70 mV and 85.20%, respectively. The InF12 nanogels were lyophilized in the presence of different concentrations of trehalose as cryoprotectant. The lyophilized InF12 containing 2%w/v trahalose (InF12-Tre2 nanogels) was chosen as final formulation which had a PS, PdI, ZP and %EE of 430.50 nm, 0.588, -16.50 mv and 82.10, respectively. The in vitro release of insulin from InF12-Tre2 nanogels in the SGF and SIF were 28.71% and 96.53%, respectively. The stability study conducted at 5±3°C for 3 months showed that lnF12-Tre2 nanogels were stable. The SDS-PAGE assay indicated that the primary structure of insulin in the lnF12-Tre2 nanogels was intact. The in-vivo study in the diabetic rats following oral administration of InF12-Tre2 nanogels at a dose of 100 IU/kg body weight reduced blood glucose level significantly to 51.10% after 6 hours compared to the control groups. Conclusions: The pH sensitive MMA/IA nanogels are potential carriers for oral delivery of insulin as they enhanced the absorption of the drug.


Assuntos
Liofilização , Insulina/administração & dosagem , Polieletrólitos/química , Polietilenoglicóis/administração & dosagem , Polietilenoimina/administração & dosagem , Administração Oral , Animais , Crioprotetores/farmacologia , Diabetes Mellitus Experimental/tratamento farmacológico , Portadores de Fármacos/química , Liberação Controlada de Fármacos , Concentração de Íons de Hidrogênio , Ponto Isoelétrico , Masculino , Ratos Sprague-Dawley , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura Ambiente , Fatores de Tempo
7.
Int J Nanomedicine ; 14: 4911-4929, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31456637

RESUMO

Background: Apocynin (APO) is a bioactive phytochemical with prominent anti-inflammatory and anti-oxidant activities. Designing a nano-delivery system targeted to potentiate the gastric antiulcerogenic activity of APO has not been investigated yet. Chitosan oligosaccharide (COS) is a low molecular weight chitosan and its oral nanoparticulate system for potentiating the antiulcerogenic activity of the loaded APO has been described here. Methods: COS-nanoparticles (NPs) loaded with APO (using tripolyphosphate [TPP] as a cross-linker) were prepared by ionic gelation method and fully characterized. The chosen formula was extensively evaluated regarding in vitro release profile, kinetic analysis, and stability at refrigerated and room temperatures. Ultimately, the in vivo antiulcerogenic activity against ketoprofen (KP)-induced gastric ulceration in rats was assessed by macroscopic parameters including Paul's index and antiulcerogenic activity, histopathological examination, immunohistochemical (IHC) evaluation of cyclooxygenase-2 (COX-2) expression level in ulcerated gastric tissue, and biochemical measurement of oxidative stress markers and nitric oxide (NO) levels. Results: The selected NPs formula with COS (0.5 % w/v) and TPP (0.1% w/v) was the most appropriate one with drug entrapment efficiency percentage of 35.06%, particle size of 436.20 nm, zeta potential of +38.20 mV, and mucoadhesive strength of 51.22%. It exhibited a biphasic in vitro release pattern as well as high stability at refrigerated temperature for a 6-month storage period. APO-loaded COS-NPs provoked marvelous antiulcerogenic activity against KP-induced gastric ulceration in rats compared with free APO treated group, which was emphasized by histopathological, IHC, and biochemical studies. Conclusion: In conclusion, APO-loaded COS-NPs could be considered as a promising oral phytopharmaceutical nanoparticulate system for management of gastric ulceration.


Assuntos
Acetofenonas/administração & dosagem , Acetofenonas/farmacologia , Quitosana/química , Mucosa Gástrica/efeitos dos fármacos , Nanopartículas/química , Oligossacarídeos/química , Compostos Fitoquímicos/administração & dosagem , Compostos Fitoquímicos/farmacologia , Acetofenonas/uso terapêutico , Administração através da Mucosa , Animais , Biomarcadores/metabolismo , Varredura Diferencial de Calorimetria , Ciclo-Oxigenase 2/metabolismo , Liberação Controlada de Fármacos , Cinética , Masculino , Nanopartículas/ultraestrutura , Óxido Nítrico/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Tamanho da Partícula , Ratos Wistar , Espectroscopia de Infravermelho com Transformada de Fourier , Eletricidade Estática , Estômago/efeitos dos fármacos , Estômago/patologia , Úlcera Gástrica/tratamento farmacológico , Úlcera Gástrica/patologia , Suínos , Difração de Raios X
8.
Bioresour Technol ; 291: 121842, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31377505

RESUMO

The spherical cellulose nanocrystals (CNCs) with high purity were prepared, the processes included composite enzymolysis of pulp fibers and the purification of product. The impurities in the crude product CNCs were analyzed with FTIR, coomassie brilliant blue-G250 and ionic chromatography. The pure CNCs were characterized with SEM, XRD, DLS and TGA. The results indicated that the crude CNCs was flocculated and washed twice with a dilute acid solution (pH = 2) to get pure spherical CNCs, the purity was approximate 99.99%. The obtained pure spherical CNCs had a narrow particle size distribution with diameter 15-40 nm. FTIR and XRD analyses proved that the crystal phase of the spherical CNCs did not change, but the crystallinity decreased slightly compared with pulp fibers. The thermal degradation showed that the spherical CNCs had better thermal stability than one from other methods, and the temperature of maximum weight loss rate (Tmax) was 329.2 °C.


Assuntos
Celulose/química , Nanopartículas/química , Temperatura Alta , Papel , Espectroscopia de Infravermelho com Transformada de Fourier
9.
J Biomed Nanotechnol ; 15(10): 2121-2129, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31462376

RESUMO

To develop a vancomycin-loaded superparamagnetic chitosan nanoparticles (Vm-SPMCNs) system for the treatment of chronic pyogenic osteoarthrosis to avoid the critical side effects caused by the systemic administration of vancomycin, the preparation process of Vm-SPMCNs was optimized by the orthogonal array design method; the optimum parameters were 1.2 g of chitosan, 0.2 g of vancomycin, 0.3 g of magnetite (Fe3O4), 12 mL of glutaraldehyde and stirring at 400 rpm. The drug loading and encapsulation efficiencies of the optimum Vm-SPMCNs were 10.30 ± 0.42% and 79.02 ± 1.81%, respectively. The Fourier transform infrared spectra confirmed that vancomycin was successfully bound to the magnetic chitosan nanoparticles. The Vm-SPMCNs were superparamagnetic particles with a diameter of 207.2 nm. The results of in vitro release tests suggested that the Vm-SPMCNs could constantly release vancomycin to maintain the concentration above the minimum inhibitory concentration for ten days, and noninvasive external magnetic stimulation could modulate the release profile according to the actual therapeutic requirements.


Assuntos
Nanopartículas de Magnetita , Quitosana , Testes de Sensibilidade Microbiana , Tamanho da Partícula , Espectroscopia de Infravermelho com Transformada de Fourier , Vancomicina
10.
World J Microbiol Biotechnol ; 35(9): 137, 2019 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-31432268

RESUMO

The presence of very high concentrations of organic pollutants, phenols, tannins and heavy metals mainly chromium in wastewater discharged from leather industries, tags it as one of the most polluting industries. The phenolic syntans discharged from tanning units have an adverse effect on living organisms and cause serious environmental pollution, thereby making it very imperative to remove it. Among various treatment methods available for removal of phenols, biodegradation is environment friendly. The present study aims at the remediation of phenolic syntan used in the leather industry employing individual as well as co-culture of Bacillus cereus and Pseudomonas aeruginosa at varying syntan concentration in the medium. Parameters such as chemical oxygen demand (COD), total organic carbon (TOC), total phenol content (TPC) and Fourier Transform Infrared Spectroscopy (FTIR) indicating biodegradation were analyzed. Promising results were observed with P. aeruginosa, which exhibited a reduction in TPC by 62-72% in all the concentrations of syntan tested just within 12 h of inoculation, whereas about 67 and 83% reduction in COD and TOC respectively was observed for 2000 ppm concentration at the end of 5 days. B. cereus also demonstrated very good reduction in the above parameters however; percentage was less as compared to P. aeruginosa. In the case of co-culture, the TPC reduction was higher than B. cereus but lesser than P. aeruginosa. The percentage reduction in TOC and COD was highest for 500 ppm which eventually decreased for subsequent concentrations.


Assuntos
Bacillus cereus/metabolismo , Resíduos Industriais , Fenóis/metabolismo , Pseudomonas aeruginosa/metabolismo , Poluentes Químicos da Água/metabolismo , Bacillus cereus/crescimento & desenvolvimento , Análise da Demanda Biológica de Oxigênio , Biotransformação , Carbono/análise , Técnicas de Cocultura , Fenóis/análise , Pseudomonas aeruginosa/crescimento & desenvolvimento , Espectroscopia de Infravermelho com Transformada de Fourier , Água/química
11.
An Acad Bras Cienc ; 91(3): e20180237, 2019 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-31365648

RESUMO

The aim of this study was to develop polyurethane (PU) wound dressing incorporated with cobalt nitrate using electrospinning technique. The morphology analysis revealed that the developed composites exhibited reduced fiber and pore diameter than the pristine PU. The electrospun membranes exhibited average porosity in the range of 67% - 71%. Energy-dispersive X-ray spectra (EDS) showed the presence of cobalt in the PU matrix. The interaction of cobalt nitrate with PU matrix was evident in Fourier transform infrared spectroscopy (FTIR) and thermogravimetric analysis (TGA). The contact angle results indicated the improved wettability of the prepared PU/cobalt nitrate composites (82° ± 2) than the pure PU (100° ± 1). The incorporation of cobalt nitrate into the PU matrix enhanced the surface roughness and mechanical strength as evident in the atomic force microscopy (AFM) and tensile test analysis. The blood compatibility assays revealed the anticoagulant nature of the prepared composites by displaying prolonged blood clotting time than the PU control. Further, the developed composite exhibited less toxicity nature as revealed in the hemolysis and cytotoxicity studies. It was observed that the PU wound dressing added with cobalt nitrate fibers exhibited enhanced physicochemical, better blood compatibility parameters and enhanced fibroblast proliferation rates which may serve as a potential candidate for wound dressings.


Assuntos
Materiais Biocompatíveis/administração & dosagem , Cobalto/administração & dosagem , Teste de Materiais , Engenharia Tecidual , Cicatrização , Materiais Biocompatíveis/química , Cobalto/química , Humanos , Microscopia Eletrônica de Varredura , Espectroscopia de Infravermelho com Transformada de Fourier
12.
Life Sci ; 234: 116777, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31465734

RESUMO

This work aimed to characterize normal, benign and malignant excised breast tissues through the analysis of the FTIR spectra of their plasma membrane proteins. Tissue characterization parameters such as peak position, peak intensity, area under the peak, relative peak intensity and relative area under peak were evaluated mainly for protein spectral peaks; 1150 cm-1, Amide I, Amide II, Amide III, and Amide A. The sensitivity, specificity and diagnostic accuracy for each parameter were obtained and Receiver Operating Characteristic (ROC) Curves were plotted. Results showed significant spectral differences between normal and benign tissues compared to malignant tissues at 1536 and 1645 cm-1. The three tissues could be distinguished at 2900 cm-1, where the malignant peak uniquely split into two separate peaks. ROC curves showed that the Amide A peak position yielded a higher accuracy compared to all other investigated characterization parameters. The deconvolution of Amide I revealed the conformational changes in plasma proteins characterizing the transformation to malignancy (a decrease in the percentage of alpha helix accompanied by an increase in the percentage of beta sheets). The use of the present structure-based analysis in conjunction with histopathological examination of excised breast tissues would offer an enhanced characterization that might reduce possible personal diagnostic mistakes.


Assuntos
Neoplasias da Mama/diagnóstico , Mama/patologia , Proteínas de Membrana/análise , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Mama/química , Neoplasias da Mama/química , Neoplasias da Mama/patologia , Feminino , Humanos , Estrutura Secundária de Proteína
13.
Water Sci Technol ; 80(1): 164-172, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31461433

RESUMO

The purpose of this study was to investigate the effect of Cu(II) on the adsorption performance and mechanism of tetracycline (TC) adsorption by natural zeolite (NZ) in aqueous solution. Low levels of Cu(II) (<0.01 mmol/L) enhanced the extent of TC adsorption from ∼0.4 mg/g (in the absence of Cu(II)) to ∼0.5 mg/g (with 0.01 mmol/L Cu(II)), resulting in 99% removal of the total TC content. The TC adsorption gradually decreased with increase in the initial pH, but the coexistence of Cu(II) lowered the extent of decrease. The adsorption process was better simulated by the pseudo-second-order kinetics model, but the isotherm model that was more fitting changed from the Langmuir to the Freundlich model as Cu(II) increased, indicating the coexistence of Cu(II) and TC altered the adsorption mechanisms. However, the residual TC in solution increased from 0 to ∼6 mg/L as the concentration of Cu(II) increased from 0 to 1 mmol/L, suggesting a competition between TC and Cu(II) for the adsorption sites in NZ. Fourier transform infrared spectroscopy analysis showed that the functional groups on the surface of NZ changed after the adsorption of TC, suggesting that complex reactions had occurred on the surface of the adsorbent.


Assuntos
Cobre/química , Tetraciclina/química , Poluentes Químicos da Água/química , Adsorção , Concentração de Íons de Hidrogênio , Cinética , Espectroscopia de Infravermelho com Transformada de Fourier , Eliminação de Resíduos Líquidos , Zeolitas/química
14.
Bioresour Technol ; 292: 121286, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31386946

RESUMO

Hydrothermal liquefaction of Ulva prolifera macroalgae (UM), an aquatic biomass, was carried out in an autoclave reactor at different temperature (270, 290 and 310 °C) and reaction holding time (10, 20 and 30 min.). The catalytic reactions of UM were carried out in the presence of three basic catalysts (KOH, NaOH and Na2CO3) with the different catalyst amount. Maximum bio-oil yield for non-catalytic liquefaction was (12.0 wt%) at 290 with 10 min reaction time. In the catalytic reaction the maximum bio-oil yield (26.7 wt%) was observed with KOH (0.1 g) catalyst. The chemical components and functional groups present in the bio-oils are identified by GC-MS, FT-IR, 1H-NMR, TGA and elemental analysis techniques. Majorly nitrogen containing compounds were found with catalytic reaction in bio-oils. The higher heating value (33.6 MJ kg-1) as well as the higher carbon content (64.2%) was observed in the case of catalytic liquefaction bio-oil.


Assuntos
Alga Marinha , Ulva , Biocombustíveis , Biomassa , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura Ambiente
15.
Bioresour Technol ; 292: 121973, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31445239

RESUMO

Twelve biochars from forest and agri-food wastes (pruning of Quercus ilex, Eucalyptus grandis, Pinus pinaster, Quercus suber, Malus pumila, Prunus spinosa, Cydonia oblonga, Eriobotrya japonica, Juglans regia, Actinidia deliciosa, Citrus sinensis and Vitis vinifera) were investigated as potential low-cost and renewable adsorbents for removal of a commonly used pharmaceutical, fluoxetine. Preliminary adsorption experiments allowed to select the most promising adsorbents, Quercus ilex, Cydonia oblonga, Eucalyptus, Juglans regia and Vitis vinifera pruning material. They were characterized by proximate, elemental and mineral analysis, thermogravimetric analysis, Fourier transform infrared spectroscopy, determination of specific surface area and pH at the point of zero charge. Batch and equilibrium studies were performed, and the influence of pH was evaluated. The equilibrium was reached in less than 15 min in all systems. The maximum adsorption capacity obtained was 6.41 mg/g for the Eucalyptus biochar, which also demonstrated a good behavior in continuous mode (packed column).


Assuntos
Fluoxetina , Poluentes Químicos da Água , Adsorção , Carvão Vegetal , Florestas , Cinética , Espectroscopia de Infravermelho com Transformada de Fourier
16.
Waste Manag Res ; 37(10): 1043-1057, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31395003

RESUMO

Thermal composting is an important and useful way to transfer raw organic matter into value-added product rich in humic substances. Furthermore, thermal composting is a very promising way to reduce deinking paper sludge pollutions, which are difficult to remove. The objective of this study was to investigate the behaviour of the composting process of deinking paper sludge with poultry manure over 14 months. Two composts were used: C1 (70/30: deinking paper sludge/poultry manure) and C2 (50/50: deinking paper sludge/poultry manure). The compost stability and maturity were assessed via physico-chemical and thermal analyses: thermogravimetric analysis, differential thermal analysis and diffuse reflectance infrared Fourier transform spectroscopy. Diffuse reflectance infrared Fourier transform spectroscopy analysis provided chemical information for the presence of aromatic, phenolic, aliphatic and polysaccharidic structures. Thermogravimetry analyses revealed that both deinking paper sludge composts were rich in humic acids. The ratio E4/E6 (fulvic acids/humic acids) was also carried out to characterise the maturity index of composts. After 14 months, the compost C2 is more stable, mature and rich in humic acids than compost C1. Furthermore, the addition of poultry manure to the deinking paper sludge-based composts enhanced the formation of humic substances. From 0 to 14 months of composting, the concentration of polychlorinated biphenyls decreased from 0.2 to 0.1 mg kg-1 and from 0.6 to 0.2 mg kg-1 for C1 and C2, respectively.


Assuntos
Compostagem , Animais , Substâncias Húmicas , Esterco , Esgotos , Solo , Espectroscopia de Infravermelho com Transformada de Fourier
17.
Int J Nanomedicine ; 14: 5147-5157, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31371953

RESUMO

Background: Kaempferol (K) is a recognized anticancer drug that can conjugate with small-size gold nanoclusters (AuNCs). Materials and methods: K-AuNCs were synthesized and their use as an anticancer drug was explored using A549 lung cancer cells. Colony formation and cell migration assays were carried out. The morphology of the K-AuNCs treated A549 cells was explored using bio-atomic force microscopy. Results: The K-AuNCs were 1-3 nm in diameter and emitted strong fluorescent at 650 nm following excitation at 550 nm. The stretching and bending nature of the K-AuNCs were analyzed by the Fourier transform infrared spectroscopy. The presence of kaempferol in the AuNCs were confirmed by the PL spectroscopy. Conclusion: The synthesized K-AuNCs mainly targeted and damaged the nuclei of the cancer cells. This composite nanocluster was less toxicity to the normal human cell and higher toxicity to the A549 lunch cancer cell and these material is potential for anticancer drug delivery and bio imaging applications.


Assuntos
Antineoplásicos/uso terapêutico , Ouro/química , Quempferóis/uso terapêutico , Neoplasias Pulmonares/tratamento farmacológico , Nanopartículas Metálicas/química , Células A549 , Antineoplásicos/química , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/patologia , Proliferação de Células/efeitos dos fármacos , Forma Celular/efeitos dos fármacos , Humanos , Quempferóis/farmacologia , Nanopartículas Metálicas/toxicidade , Nanopartículas Metálicas/ultraestrutura , Fenômenos Ópticos , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
18.
Int J Nanomedicine ; 14: 5381-5396, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31409994

RESUMO

Background: Tacrolimus (TCR), also known as FK-506, is a biopharmaceutics classification system (BCS) class II drug that is insoluble in water because of its high log P values. After dermal application, TCR remains in the stratum corneum and passes through the skin layers with difficulty. Purpose: The objectives of this study were to develop and evaluate solid lipid nanoparticles (SLNs) with thermosensitive properties to improve penetration and retention. Methods: We prepared TCR-loaded thermosensitive solid lipid nanoparticles (TCR-SLNs) with different types of surfactants on the shell of the particle, which conferred the advantages of enhancing skin permeation and distribution. We also characterized them from a physic point of view and performed in vitro and in vivo evaluations. Results: The TCR contained in the prepared TCR-SLN was in an amorphous state and entrapped in the particles with a high loading efficiency. The assessment of ex vivo skin penetration using excised rat dorsal skin showed that the TCR-SLNs penetrated to a deeper layer than the reference product (0.1% Protopic®). In addition, the in vivo skin penetration test demonstrated that TCR-SLNs delivered more drug into deeper skin layers than the reference product. FT-IR images also confirmed drug distribution of TCR-SLNs into deeper layers of the skin. Conclusion: These results revealed the potential application of thermosensitive SLNs for the delivery of difficult-to-permeate, poorly water-soluble drugs into deep skin layers.


Assuntos
Derme/metabolismo , Lipídeos/química , Nanopartículas/química , Tacrolimo/farmacologia , Temperatura Ambiente , Administração Cutânea , Animais , Varredura Diferencial de Calorimetria , Derme/efeitos dos fármacos , Liberação Controlada de Fármacos , Irritantes/toxicidade , Nanopartículas/ultraestrutura , Tamanho da Partícula , Coelhos , Ratos Sprague-Dawley , Absorção Cutânea/efeitos dos fármacos , Testes Cutâneos , Espectroscopia de Infravermelho com Transformada de Fourier , Tensoativos/química , Difração de Raios X
19.
Food Chem ; 298: 125015, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31260956

RESUMO

The effect of microwave irradiation-retrogradation (MIR) treatment on the physicochemical properties and in vitro digestibility of corn starch (A-type crystallinity), potato starch (B-type) and chestnut starch (C-type) were evaluated. After MIR treatment, the amount of resistant starch (RS) increased and rapid digestible starch (RDS) decreased along with the retrogradation time in all three starches. The degree of retrogradation (DR) of starch was significantly positive correlated with amylose and RS content. All three starches subjected to MIR treatment exhibited a B-type crystalline structure. With the increase in retrogradation time, starch granules became more orderly. The DR was significantly positively correlated with relative crystallinity of X-ray pattern, To, ΔH of thermal properties, and the Fourier transform infrared ratio of 1047/1022 cm-1 of starch. The results indicated that MIR treatment is a good industrial method for preparing low digestive starch and retrogradation time is an important parameter for the process.


Assuntos
Amilose/efeitos da radiação , Amido/efeitos da radiação , Amilose/química , Fenômenos Químicos/efeitos da radiação , Cristalização , Micro-Ondas , Espectroscopia de Infravermelho com Transformada de Fourier , Amido/química , Difração de Raios X
20.
Anal Bioanal Chem ; 411(21): 5593-5603, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31289896

RESUMO

A novel SBA-15-based fluorescent sensor, SBA-PI: mesoporous SBA-15 structure modified with iminostilbene groups, was designed, synthesized, and characterized by Fourier transform-infrared spectroscopy (FT-IR), ultraviolet-visible spectroscopy, field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDS), thermogravimetric analysis (TGA), low-angle X-ray diffraction techniques (low-angle XRD), and N2 adsorption-desorption techniques. The SBA-PI as a sensor with a selective behavior for detection of Cu2+ comprises iminostilbene carbonyl as the fluorophore group. The SBA-PI sensor displays an excellent fluorescence response in aqueous solutions and the fluorescence intensity quenches remarkably upon addition of Cu2+. Other common interfering ions even at high concentration ratio showed either no or very small changes in the fluorescence intensity of SBA-PI in the absence of Cu2+. A limit of detection of 8.7 × 10-9 M for Cu2+ indicated that this fluorescence sensor has a high sensitivity and selectivity toward the target copper (II) ion. The fabricated Cu2+ sensor was successfully applied for the determination of the Cu2+ in human blood samples without any significant interference. With the selective analysis of Cu2+ ions down to 0.9 nM in blood, the sensor is a promising and a novel detection candidate for Cu2+ and can be applied in the clinical laboratory. A reversibility and accuracy in the fluorescence behavior of the sensor was found in the presence of I¯ that was described as a masking agent for Cu2+. Graphical abstract.


Assuntos
Cobre/sangue , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Oligoelementos/sangue , Humanos , Concentração de Íons de Hidrogênio , Limite de Detecção , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Difração de Pó , Espectrometria por Raios X , Termogravimetria
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