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1.
Heliyon ; 9(8): e18632, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37576303

RESUMO

Sustainable management of non-edible agricultural residues of cashew nut production is a concern in Colombia. Therefore, this study aimed to study the fatty acid content of a pyrolytic liquid obtained from cashew nut shells (CNSs) from the Vichada region in Colombia. Transesterification of pyrolytic liquid was conducted to obtain biodiesel at the micro-scale as the first approach for this valorization route. Proximal analysis of samples was carried out using advanced analytical techniques (UHPLC-MS and CG-MS) whereas phenolic content and antioxidant activity were determined. The production yield of pyrolytic liquid was 69.15 ± 5.07% weight (wt.), at 550 °C and 2h of pyrolysis and the liquid was rich in fatty acids (∼70% wt.) and long-chain phenols (∼18% wt.). Among the phenolic compounds in liquid, mainly unsaturated C15:4 cardanol was identified (82.1 ± 5.5 mg/g), whereas the antioxidant activity of pyrolytic liquid was 0.714 ± 0.030 TE/g. Moreover, the biodiesel yield was 81% using catalyst sodium methoxide (12% v), and 50 °C and 26 min for the reaction. The obtained biodiesel in the hexane fraction was rich in methyl trans-8-octadecanoate (20.9 % wt.) and methyl palmitate (14.3 % wt.), being the representative compounds in the biodiesel. Therefore, the results indicated that thermal conversion of CNSs for obtaining biodiesel on a one-step process is a suitable strategy for the management of toxic and non-edible cashew residues. Finally, this is the first work of its kind that propose in detail the composition of pyrolytic liquid obtained from Colombian cashew nut residues under the proximate analysis approach and using advanced analytical techniques.

2.
Heliyon ; 8(5): e09528, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35663750

RESUMO

Cashew nut production generates large amounts of cashew apple as residue. In Colombia, cashew cultivation is increasing together with the concerns on residue management. The objective of this study was to provide the first chemical, physical and thermal decomposition characterization of cashew apple from Colombian varieties harvested in Vichada, Colombia. This characterization was focused to identify the important bioactive and natural compounds that can be further valorized in the formulation of food, nutraceuticals, and pharmacological products. The results obtained in this study are helpful to portray the cashew apple as a potential by-product due to its renewable nature and valuable composition, instead of seeing it just as an agricultural residue. For that, cashew apples of Regional 8315 and Mapiria varieties were studied. The natural juice (cashew apple juice) that was extracted from the cashew apples and the remanent solids (cashew apple bagasse) were separately analyzed. The HPLC analytical technique was used to determine the concentration of bioactive compounds, structural carbohydrates, and soluble sugars that constitute this biomass. Spectrophotometric techniques were used to determine the concentration of tannins, carotenoids, and total polyphenols. Mineral content and antioxidant activity (DPPH and ABTS assays) were determined in the biomass. Also, the thermal decomposition under an inert atmosphere or pyrolysis was performed on cashew apple bagasse. The varieties of cashew apple studied in this work showed similar content of bioactive compounds, total phenolic content, and structural carbohydrates. However, the Mapiria variety showed values slightly higher than the Regional 8315. Regarding cashew apple juice, it is rich in tannins and ascorbic acid with values of 191 mg/100 mL and 70 mg/100 mL, respectively, for Mapiria variety. Additionally, the principal reservoir of bioactive compounds and constitutive carbohydrates was the cashew apple bagasse. About 50 wt.% of it was composed of cellulose and hemicellulose. Also, in the bagasse, the ascorbic acid content was in a range of 180-200 mg/100 g, which is higher than other fruits and vegetables. Moreover, alkaloids were identified in cashew apples. The maximum value of antioxidant activity (DPPH assay: 405 TEs/g) was observed in the bagasse of Mapiria variety. The bagasse thermal decomposition started around 150 °C when the structural carbohydrates and other constitutive substances started to degrade. After thermogravimetric analysis, a remanent of 20% of the initial weight suggested the formation of a rich-carbon solid, which could correspond to biochar. Therefore, the cashew apple harvested in Vichada is a valuable reservoir of a wide range of biomolecules that potentially could be valorized into energy, foods, and pharmacologic applications. Nevertheless, future work is necessary to describe the complex compounds of this residual biomass that are still unknown.

3.
J Fungi (Basel) ; 8(1)2021 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-35049947

RESUMO

This research aimed to establish the relationship between carbon-nitrogen nutritional factors and copper sulfate on laccase activity (LA) by Pleurotus ostreatus. Culture media composition was tested to choose the nitrogen source. Yeast extract (YE) was selected as a better nitrogen source than ammonium sulfate. Then, the effect of glucose and YE concentrations on biomass production and LA as response variables was evaluated using central composite experimental designs with and without copper. The results showed that the best culture medium composition was glucose 45 gL-1 and YE 15 gL-1, simultaneously optimizing these two response variables. The fungal transcriptome was obtained in this medium with or without copper, and the differentially expressed genes were found. The main upregulated transcripts included three laccase genes (lacc2, lacc6, and lacc10) regulated by copper, whereas the principal downregulated transcripts included a copper transporter (ctr1) and a regulator of nitrogen metabolism (nmr1). These results suggest that Ctr1, which facilitates the entry of copper into the cell, is regulated by nutrient-sufficiency conditions. Once inside, copper induces transcription of laccase genes. This finding could explain why a 10-20-fold increase in LA occurs with copper compared to cultures without copper when using the optimal concentration of YE as nitrogen sources.

4.
PLoS One ; 12(6): e0179428, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28636672

RESUMO

Cordyceps sensu lato is a genus of arthropod-pathogenic fungi, which have been used traditionally as medicinal in Asia. Within the genus, Ophiocordyceps sinensis is the most coveted and expensive species in China. Nevertheless, harvesting wild specimens has become a challenge given that natural populations of the fungus are decreasing and because large-scale culture of it has not yet been achieved. The worldwide demand for products derived from cultivable fungal species with medicinal properties has increased recently. In this study, we propose a new species, Cordyceps nidus, which parasitizes underground nests of trapdoor spiders. This species is phylogenetically related to Cordyceps militaris, Cordyceps pruinosa, and a sibling species of Cordyceps caloceroides. It is found in tropical rainforests from Bolivia, Brazil, Colombia and Ecuador. We also investigated the medicinal potential of this fungus based on its biochemical properties when grown on four different culture media. The metabolic profile particularly that of nucleosides, in polar and non-polar extracts was determined by UPLC, and then correlated to their antimicrobial activity and total phenolic content. The metabolome showed a high and significant dependency on the substrate used for fungal growth. The mass intensities of nucleosides and derivative compounds were higher in natural culture media in comparison to artificial culture media. Among these compounds, cordycepin was the predominant, showing the potential use of this species as an alternative to O. sinensis. Furthermore, methanol fractions showed antimicrobial activity against gram-positive bacteria, and less than 3.00 mg of gallic acid equivalents per g of dried extract were obtained when assessing its total phenolic content by modified Folin-Ciocalteu method. The presence of polyphenols opens the possibility of further exploring the antioxidant capacity and the conditions that may enhance this characteristic. The metabolic composition and biochemical activity indicate potential use of C. nidus in pharmaceutical applications.


Assuntos
Antibacterianos/farmacologia , Antioxidantes/farmacologia , Cordyceps/metabolismo , Bactérias Gram-Positivas/efeitos dos fármacos , Metabolômica , Nucleosídeos/metabolismo , Ásia , Cordyceps/crescimento & desenvolvimento
5.
Aval. psicol ; 14(3): 299-307, dez. 2015.
Artigo em Português | LILACS | ID: lil-772466

RESUMO

Este artículo centra su interés en la importancia de la validez dentro de los procesos de evaluación psicológica cuando se pretende evaluar a personas invidentes o con baja visión, y en el desarrollo de los Test Adaptativos Informatizados (TAI) como una alternativa para la evaluación de esta población. Se presenta una revisión sobre el concepto de validez a partir de las aproximaciones contemporáneas dominantes, y se habla acerca del desarrollo de los TAI, el problema de su validez y los alcances de esta tecnología como una alternativa para evaluar personas con baja visión o invidentes. Finalmente, este trabajo deja abierta la posibilidad para futuros desarrollos e investigaciones en torno a otras alternativas de evaluación con equidad para poblaciones con discapacidad física.


Este artigo centra o seu interesse na importância da validade dentro dos processos de avaliação psicológica de pessoas cegas ou com baixa visão e no desenvolvimento dos Testes Adaptativos Computadorizados (TAC) como uma alternativa para a avaliação dessa população. Apresenta-se uma revisão sobre o conceito de validade a partir das abordagens contemporâneas dominantes e sobre o desenvolvimento dos TAC, o problema da sua validade e os alcances dessa tecnologia como uma alternativa para avaliar pessoas cegas. Finalmente, o trabalho deixa em aberto a possibilidade de futuros desenvolvimentos e pesquisas sobre alternativas de avaliação com equidade para a população com deficiência física.


This article focuses on the importance of validity in the process of psychological evaluation, especially when the evaluation is intended for people with visual impairment, and about the development of the Computerized Adaptive Testing (CAT) as an alternative for the assessment of this population. First, a review of the main controversies about the concept of validity and the development of Computerized Adaptive Test is presented. Then, topics related to validity in CAT and scope, technological limitations, and the challenges of its use as an alternative to evaluate the visual impairment population are discussed. Finally, possibilities for future developments and research on high quality alternative assessment for populations with physical disabilities are set forth.


Assuntos
Humanos , Baixa Visão/psicologia , Diagnóstico por Computador/psicologia , Pessoas com Deficiência Visual/psicologia
6.
Aval. psicol ; 14(3): 299-307, dez. 2015.
Artigo em Espanhol | Index Psicologia - Periódicos | ID: psi-66560

RESUMO

Este artículo centra su interés en la importancia de la validez dentro de los procesos de evaluación psicológica cuando se pretende evaluar a personas invidentes o con baja visión, y en el desarrollo de los Test Adaptativos Informatizados (TAI) como una alternativa para la evaluación de esta población. Se presenta una revisión sobre el concepto de validez a partir de las aproximaciones contemporáneas dominantes, y se habla acerca del desarrollo de los TAI, el problema de su validez y los alcances de esta tecnología como una alternativa para evaluar personas con baja visión o invidentes. Finalmente, este trabajo deja abierta la posibilidad para futuros desarrollos e investigaciones en torno a otras alternativas de evaluación con equidad para poblaciones con discapacidad física.(AU)


Este artigo centra o seu interesse na importância da validade dentro dos processos de avaliação psicológica de pessoas cegas ou com baixa visão e no desenvolvimento dos Testes Adaptativos Computadorizados (TAC) como uma alternativa para a avaliação dessa população. Apresenta-se uma revisão sobre o conceito de validade a partir das abordagens contemporâneas dominantes e sobre o desenvolvimento dos TAC, o problema da sua validade e os alcances dessa tecnologia como uma alternativa para avaliar pessoas cegas. Finalmente, o trabalho deixa em aberto a possibilidade de futuros desenvolvimentos e pesquisas sobre alternativas de avaliação com equidade para a população com deficiência física.(AU)


This article focuses on the importance of validity in the process of psychological evaluation, especially when the evaluation is intended for people with visual impairment, and about the development of the Computerized Adaptive Testing (CAT) as an alternative for the assessment of this population. First, a review of the main controversies about the concept of validity and the development of Computerized Adaptive Test is presented. Then, topics related to validity in CAT and scope, technological limitations, and the challenges of its use as an alternative to evaluate the visual impairment population are discussed. Finally, possibilities for future developments and research on high quality alternative assessment for populations with physical disabilities are set forth.(AU)


Assuntos
Diagnóstico por Computador/psicologia , Baixa Visão/psicologia , Pessoas com Deficiência Visual/psicologia , Reprodutibilidade dos Testes
7.
J Microbiol Biotechnol ; 23(5): 689-98, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23648860

RESUMO

The production and characterization of an active recombinant N-acetylgalactosamine-6-sulfate sulfatase (GALNS) in Escherichia coli BL21(DE3) has been previously reported. In this study, the effect of the signal peptide (SP), inducer concentration, process scale, and operational mode (batch and semi-continuous) on GALNS production were evaluated. When native SP was presented, higher enzyme activity levels were observed in both soluble and inclusion bodies fractions, and its removal had a significant impact on enzyme activation. At shake scale, the optimal IPTG concentrations were 0.5 and 1.5 mM for the strains with and without SP, respectively, whereas at bench scale, the highest enzyme activities were observed with 1.5 mM IPTG for both strains. Noteworthy, enzyme activity in the culture media was only detected when SP was presented and the culture was carried out under semi-continuous mode. We showed for the first time that the mechanism that in prokaryotes recognizes the SP to mediate sulfatase activation can also recognize a eukaryotic SP, favoring the activation of the enzyme, and could also favor the secretion of the recombinant protein. These results offer significant information for scaling-up the production of human sulfatases in E. coli.


Assuntos
Condroitina Sulfatases/metabolismo , Meios de Cultura/metabolismo , Escherichia coli/metabolismo , Sinais Direcionadores de Proteínas , Condroitina Sulfatases/química , Condroitina Sulfatases/genética , Escherichia coli/genética , Humanos , Engenharia de Proteínas , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/química , Proteínas Recombinantes/genética
8.
Enfer. tórax (Lima) ; 43(1): 33-43, ene.-abr. 2000. tab, graf
Artigo em Espanhol | LIPECS | ID: biblio-1107917

RESUMO

Realizamos un estudio descriptivo retrospectivo que comprende 12 años y 6 meses en los pacientes del programa de EPOC del Hospital EsSalud Cusco. Evaluamos 160 pacientes naturales y residentes de altura. El 62 por ciento son varones entre los 50 y 79 años; los profesionales preponderán, siendo los profesores el 78.6 por ciento. El 50.6 por ciento de los pacientes tuvieron hábito tabáquico, el 7.5 por ciento persiste fumando; el 38.7 por ciento de ellos llegaron a consumir más de 15 cig./día. El 100 por ciento de los casos estuvieron expuestos a contaminantes por combustión intradomiciliaria (humo de leño) y el 35 por ciento de los casos reporta ser fumadores pasivos. El 91.9 por ciento tuvo antecedentes de enfermedad respiratoria en su niñez y juventud; el 38.8 por ciento indican que sus familiares no tuvieron EPOC y/o asma. El 57.5 por ciento tiene ECG normal, la alteración saltante es el BIRDHH; se encontró 17 casos de poliglobulia. Existe tendencia al sobre peso. La espirometría en el 47.5 por ciento de los casos son normales al ingreso, en el control 40.4 por ciento; predomina el estadío moderado. El 80 por ciento de la radiología es compatible con bronquitis crónica, en el 17.5 por ciento es normal. La tos, espectoración blanca, dísnea y roncus son síntomas preponderantes en el 80 por ciento. Los síntomas inician en la segunda década de vida. El 56.7 por ciento no evidencia mejoría al tratamiento. El 34.4 por ciento fueron evaluados en emergencia y el 9.4 por ciento fueron hospitalizados por infecciones respiratorias.


Assuntos
Humanos , Altitude , Bronquite/diagnóstico por imagem , Bronquite/epidemiologia , Enfisema/diagnóstico por imagem , Enfisema/epidemiologia , Pneumopatias Obstrutivas/diagnóstico por imagem , Pneumopatias Obstrutivas/epidemiologia , Epidemiologia Descritiva , Estudos Retrospectivos
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