The aim of this study was to evaluate the potential of Hancornia speciosa GOMES (mangaba) seeds as a novel matrix for the production of bio-oil. The study was divided into three steps: (i) characterization of the biomass (through elemental analysis (CHN), infrared spectroscopy (FTIR-ATR), thermogravimetry (TG), and determination of biomass composition; (ii) pyrolysis of mangaba seed to obtain the bio-oil; and (iii) characterization of the bio-oil (thermogravimetry and gas chromatography/mass spectrometry-GC/qMS). The TG of the sample showed a mass loss of around 90% in 450°C. In the pyrolysis experiments the variables included temperature (450 and 600°C), sample mass (5 and 11g) and prior heating (with or without), with the best conditions of 600°C, 11g of seeds and prior heating of the furnace. The GC/qMS analysis identified carboxylic acids and hydrocarbons as the major components, besides the presence of other compounds such as furanes, phenols, nitriles, aldehydes, ketones, and amides.
Resumo Contexto As doenças vasculares influenciam a qualidade de vida (QV) e afetam de forma direta o aspecto biopsicossocial dos indivíduos. Sendo assim, a QV é uma importante forma de avaliação das intervenções vasculares. Objetivo Avaliar a QV em pacientes com doença arterial periférica internados no serviço de cirurgia vascular em um hospital terciário beneficente. Métodos Trata-se de um estudo exploratório, com desenho transversal, em um serviço de cirurgia vascular em um hospital terciário beneficente, no qual pacientes com doença arterial periférica foram avaliados através de dois questionários, sendo um a respeito de qualidade de vida (versão abreviada WHOQOL-Bref) e outro sobre as condições sociodemográficas. Resultados Foi observado que os domínios físico, meio ambiente e QV total obtiveram os menores escores entre os 127 entrevistados. Além disso, uma análise intragrupo demonstrou que os homens obtiveram pontuação maior em todos os domínios quando comparados às mulheres, com exceção do domínio de relações sociais. Conclusão As mulheres com doença arterial periférica apresentaram uma menor pontuação em todos os domínios do questionário de QV, exceto no de relações sociais, quando comparadas aos homens.
Guava seed biochar appears as a new alternative of the effective support to the immobilization of Burkholderia cepacia lipase (BCL) by physical adsorption. The objective of this work was to evaluate the potential of this immobilized biocatalyst in the transesterification reaction of crude coconut oil and ethanol and to understand the mechanism of the reaction through the study of molecular docking. The best loading of BCL was determined to be 0.15 genzyme/gsupport having a hydrolytic activity of 260 U/g and 54% immobilization yield. The products of transesterification reaction produced a maximum yield at 40 °C under different reaction conditions. The monoacylglycerols (MAGs) conversion of 59% was using substrate molar ratio oil:ethanol of 1:7 with the reaction time of 24 H. In addition, the highest ethyl esters yield (48%) had the molar ratio of 1:7 with the reaction time of 96 H and maximum conversion of diacylglycerols (DAGs) was 30% with the molar ratio of 1:6 with the reaction time of 24 H. Molecular Docking was applied to clarify the mechanisms of transesterification reaction at the molecular level. MAGs and DAGs are compounds with excellent emulsifying properties used in industrial production of several bioproducts such as cosmetic, pharmaceuticals, foods, and lubricants.
The use of agricultural residues for the production of bio-oil is an important alternative to the use of fossil fuels. In this study, the Caupi bean pod (Vigna unguiculata) was characterized and used as biomass in the production of bio-oil. This biomass was evaluated in terms of physicochemical, morphological (scanning electron microscopy (SEM)), and thermal (thermogravimetric analysis (TGA), differential scanning calorimetry (DSC)) characterization, lignocellulosic composition, and pyrolysis processes. The pyrolysis was carried out in a stainless steel fixed-bed reactor (260 mm in length and 60 mm in diameter) under atmospheric nitrogen pressure. Pyrolysis was conducted at 550, 600, and 700 °C and N 2 gas flow of 2, 5, and 7 mL min-1. The chemical composition of the bio-oils was studied through CHN, TGA, Fourier-transform infrared spectroscopy (FTIR), and gas chromatography-mass spectrometry (GC-MS). The results confirmed the bean pod's potential in the thermochemical process. The thermogravimetric analyses demonstrate that there can be a relationship between the components of the principal biomass (cellulose, hemicellulose, and lignin) and the compounds present in the bio-oil. The obtained bio-oils represent bio-products that are rich in compounds of several chemical classes with relevant commercial value such as acids (palmitic, linoleic, oleic, and stearic), alcohols (ethylene glycol), sugars (levoglucosan), and phenols (guaiacol, catechol, phenol, and pyrocatechol).
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Ultrasonic pretreatment of cowpea bean pod biomass with addition of tripotassium phosphate (K3PO4) was used to induce the production of bio-oil enriched in phenolic compounds. An ultrasound bath operating at 40 kHz, 154 W power, and constant biomass:K3PO4 ratio of 5:1 (m/m) was used for pretreatments with different durations: 0.5, 1.5, 3, 6, 8, and 12 h. After the pretreatment, the biomass was pyrolyzed in a fixed bed reactor at 600 °C, under a flow of N2 at 5 mL min-1. The pyrolysis results indicated that the use of K3PO4 reduced the bio-oil yield, when compared to non-catalytic pyrolysis, and that the use of ultrasound caused increased biomass devolatilization, increasing the gas yield and reducing the formation of biochar. Gas chromatography mass spectrometry (GC-MS) analysis of the bio-oils indicated that pretreatment of the biomass led to significant increases of the phenolics contents, as well as alteration of the chemical profile of these compounds. The highest phenolics content of 8.12% m/m was obtained for the biomass submitted to 1.5 h of ultrasonic pretreatment, compared to 4.89% m/m for the untreated biomass.
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