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1.
Food Chem ; 302: 125334, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31419773

RESUMO

Carotenoids, natural pigments, are a group of chemically heterogeneous molecules, present in numerous taxonomical clusters. Because of their various bioactivities, carotenoids are day-by-day applied in numerous fields. The present work aimed to investigate an efficient extraction process of carotenoids from blue crab shells and their identification by HR-ESI-MS technique. In this context, different methods (enzymatic, maceration, Soxhlet, etc.) and solvents (variable polarity index) were tested. Maceration using the binary system hexane/isopropanol (50/50) was found to be the most efficient process, producing high carotenoids content and low total phenolic and soluble protein amounts (p < 0.05). When combined with an enzymatic pretreatment, this procedure was found to be remarkably (p < 0.05) more efficient and selective especially towards astaxanthin (p < 0.05). The HR-ESI-MS identified 23 compounds, depending on the adopted extraction approach. The compounds identified may have potential for applications in food or pharmaceutical industries.


Assuntos
Exoesqueleto/química , Braquiúros/química , Carotenoides/isolamento & purificação , Fracionamento Químico/métodos , 2-Propanol/química , Animais , Carotenoides/análise , Hexanos/química , Fenóis/análise , Fenóis/química , Proteínas/análise , Proteínas/isolamento & purificação , Solventes/química , Espectrometria de Massas por Ionização por Electrospray , Espectroscopia de Infravermelho com Transformada de Fourier , Xantofilas/análise , Xantofilas/isolamento & purificação
2.
Food Chem ; 303: 125392, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31446362

RESUMO

In this article, an easy and quick method based on microwave assisted acid digestion technique prior to quantification using inductively coupled plasma mass spectrometry for the analysis of heavy metals in cocoa beans, cocoa powder and chocolate was established and validated for arsenic (As), cadmium (Cd), lead (Pb), and antimony (Sb). Limit of quantification for all elements were product dependent and varies from 7.84 to 194.52 µg/kg. The recoveries of the heavy metals at 250 and 1000 µg/kg spiking levels were ranged between 96.27-108.75%, 90.43-101.97% and 89.72-106.26% for cocoa beans, cocoa powder, and chocolate, respectively. Relative standard deviation values obtained were all below 20% and the expanded uncertainty measurements for the elements were less than 25%. The analysis of real samples found that the concentration level is far from the national alarming level except for cadmium in cocoa beans.


Assuntos
Cacau/química , Fracionamento Químico/métodos , Espectrometria de Massas/métodos , Metais Pesados/análise , Micro-Ondas , Sementes/química , Antimônio/análise , Arsênico/análise , Cádmio/análise , Chocolate/análise , Chumbo/análise
3.
Food Chem ; 303: 125394, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31473455

RESUMO

A simple and effective vesicle based ultrasonic-assisted extraction (UAE) method was developed for extraction of active compounds in functional food. The target analytes were determined by ultra-high performance liquid chromatography with ultraviolet detector. Surfactant vesicle was adopted as extraction solvent. Different operating conditions including the type and concentration of vesicle, extraction time and solid to liquid ratio were investigated by single-factor experiments and response surface methodology. Optimized experimental conditions were 1% (w/v) of DTAB/SDS vesicle, 20 min of extraction time and 160 mg/mL of solid to liquid ratio. The proposed method provided good linearity in the linear range of 10-1000 µg/mL with regression coefficients larger than 0.999, low limits of detection of 27.64-55.67 ng/mL, good precision with relative standard deviations below 0.35%, and satisfactory recoveries of 83.84-90.92% for tested saponins. Consequently, the proposed vesicle based UAE method was well suited for the extraction of saponins in Panax notoginseng.


Assuntos
Fracionamento Químico/métodos , Panax notoginseng/química , Saponinas/isolamento & purificação , Ultrassom , Cromatografia Líquida de Alta Pressão , Saponinas/análise
4.
Sci Total Environ ; 691: 1082-1088, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31466190

RESUMO

The turmeric industry produces a huge amount of residues annually. After undergoing different extraction process, turmeric residue biomass may be transformed from waste to resource. Turmeric residues exhibit different characteristics suitable for various environmental applications. In this work, the adsorption of Cu(II) onto turmeric residues from microbial (TR-A) and chemical (TR-B) extraction was investigated. The characteristics of the residues were examined via Brunauer-Emmett-Teller analysis, thermogravimetric analysis, scanning electron microscopy, Fourier-transform infrared spectroscopy, and elemental analysis. Then, applications to Cu(II) immobilization were identified. Results suggested that although TR-B had better thermal stability, larger surface area, and more pores than TR-A, the adsorption capacity of Cu(II) onto TR-A was higher (13.12 mg/g) than that onto TR-B (7.37 mg/g) because TR-A had more microbial cell debris, metabolites, and S element than TR-B. In practice, TR-A-added soil achieved 40% more Cu immobilization than TR-B-added soil under continuous leaching of simulated acid rain. Consequently, the residues extracted using the microbial method prevented pollution after the traditional extraction process and transformed waste into a material for environmental remediation.


Assuntos
Cobre/química , Curcuma/química , Recuperação e Remediação Ambiental/métodos , Adsorção , Fracionamento Químico , Cinética , Espectroscopia de Infravermelho com Transformada de Fourier
5.
J Agric Food Chem ; 67(37): 10296-10305, 2019 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-31464437

RESUMO

Grass pea is an orphan legume that is grown in many places in the world. It is a high-protein, drought-tolerant legume that is capable of surviving extreme environmental challenges and can be a sole food source during famine. However, grass pea produces the neurotoxin ß-N-oxalyl-L-α,ß-diaminopropionic acid (ß-ODAP), which can cause a neurological disease. This crop is promising as a food source for both animals and humans if ß-ODAP levels and other antinutritional factors such as protease inhibitors are lowered or removed. To understand more about these proteins, a proteomic analysis of grass pea was conducted using three different extraction methods to determine which was more efficient at isolating antinutritional factors. Seed proteins extracted with Tris-buffered saline (TBS), 30% ethanol, and 50% isopropanol were identified by mass spectrometry, resulting in the documentation of the most abundant proteins for each extraction method. Mass spectrometry spectral data and BLAST2GO analysis led to the identification of 1376 proteins from all extraction methods. The molecular function of the extracted proteins revealed distinctly different protein functional profiles. The majority of the TBS-extracted proteins were annotated with nutrient reservoir activity, while the isopropanol extraction yielded the highest percentage of endopeptidase proteinase inhibitors. Our results demonstrate that the 50% isopropanol extraction method was the most efficient at isolating antinutritional factors including protease inhibitors.


Assuntos
Fracionamento Químico/métodos , Fabaceae/química , Extratos Vegetais/isolamento & purificação , Inibidores de Proteases/isolamento & purificação , Sementes/química , Endopeptidases/química , Fabaceae/genética , Fabaceae/metabolismo , Espectrometria de Massas , Extratos Vegetais/química , Extratos Vegetais/metabolismo , Proteínas de Plantas/química , Proteínas de Plantas/genética , Proteínas de Plantas/isolamento & purificação , Proteínas de Plantas/metabolismo , Inibidores de Proteases/química , Inibidores de Proteases/metabolismo , Proteômica , Sementes/genética , Sementes/metabolismo
6.
J Agric Food Chem ; 67(35): 9840-9850, 2019 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-31424924

RESUMO

In the present study, methanolysis of poplar biomass was conducted for the selective transformation of hemicellulose and lignin, which leads to methyl glycosides (mainly C5 glycosides) and lignin fragments in the liquefied products that can be separated according to their difference in hydrophilicity. The distribution of methyl glycosides and delignification was dependent on the presence of acid catalysts and reaction temperatures. The obtained lignin fraction was separated into solid lignin fragments and liquid lignin oil according to their molecular weight distribution. Subsequently, directional conversion of methyl C5 glycosides into methyl levulinate was performed with dimethoxymethane/methanol as the cosolvent. A yield of 12-30% of methyl levulinate yield (based on the methyl glycoside) was achieved under these conditions. The remaining cellulose-rich substrate showed enhanced susceptibility to enzymatic hydrolysis, resulting in a yield of glucose of above 70%. Overall, the described strategy shows practical implications for the effective valorization of biomass.


Assuntos
Fracionamento Químico/métodos , Glucose/isolamento & purificação , Ácidos Levulínicos/isolamento & purificação , Metanol/química , Fenóis/isolamento & purificação , Extratos Vegetais/isolamento & purificação , Populus/química , Madeira/química , Catálise , Celulose/química , Celulose/isolamento & purificação , Glucose/química , Ácidos Levulínicos/química , Lignina/química , Lignina/isolamento & purificação , Fenóis/química , Extratos Vegetais/química
7.
An Acad Bras Cienc ; 91(3): e20180621, 2019 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-31411258

RESUMO

Aristolochia triangularis Cham., is one of the most frequently used medicinal plant in Southern Brazil. Preparations containing the leaves and/or stems are traditionally used as anti-inflammatory, diuretic, as well as antidote against snakebites. This study screened A. triangularis extracts, fractions and isolated compounds for different bioactivities. A weak antiproliferative activity against human lung cancer cell line (A549) was observed only for chloroform fraction obtained from stems (CFstems - CC50: 2.93 µg/mL). Also, a moderate antimicrobial activity against Staphylococcus aureus was detected just for chloroform fraction obtained from leaves (CFleaves -13-16 mm inhibition zone). Additionally, two semi-purified fractions (CFstems-4 and CFleaves-4) selectively inhibited HSV-1 replication (IC50 values of 0.40 and 2.61 µg/mL, respectively), while only CFleaves showed promising results against Leishmania amazonensis. Fractionation of extracts resulted in the isolation of one neolignan (-) cubebin and one lignan (+) galbacin. However, these compounds are not responsible for the in vitro bioactivities herein detected. The presence of aristolochic acid I and aristolochic acid II in the crude ethanol extract of stems (CEEstems) and leaves (CEEleaves) was also investigated. The HPLC analysis of these extracts did not display any peak with retention time or UV spectra comparable to aristolochic acids I and II.


Assuntos
Aristolochia/química , Compostos Fitoquímicos/química , Antibacterianos/farmacologia , Antifúngicos/farmacologia , Antiprotozoários/farmacologia , Antivirais/farmacologia , Ácidos Aristolóquicos/química , Brasil , Fracionamento Químico , Cromatografia Líquida de Alta Pressão/métodos , Humanos , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/farmacologia
8.
Environ Monit Assess ; 191(9): 578, 2019 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-31432272

RESUMO

A possible impact of sample preparation on the chemical fractionation results is generally underestimated in studies of forms of occurrence of heavy metals in river sediments. Our analysis of the recently published results of sequential extraction of chromium has revealed the effect of sample grinding on the result of determination of mobile chromium fractions in river sediments. This observation has been experimentally verified along with the analysation of potential effect of river sediment drying conditions on chromium distribution pattern. The studies were carried out on river sediments polluted with tannery effluents (Cr, 29.2-233 mg/kg). The determined content of chromium bound to carbonates in powdered samples was 2 to 7 times higher than those in raw river sediment samples. It was shown that the main reason was the different kinetic characteristics of chromium leaching in these sediments. Using the shrinking core model, it was found that diffusion through the "ash layer" was the rate-controlling step during the extraction of the carbonate fraction of chromium. It has been additionally confirmed that common air drying of sediment samples does not affect the results of chemical fractionation of chromium.The results of our studies are also vital for the assessment of environmental risk posed by river sediments polluted with heavy metals. In the case of sediment samples used in this study, powdering changed the risk category (RAC) from low risk to high risk. Hence, in order to achieve a realistic assessment of chromium mobility and environmental risk, it is advisable to use raw samples, despite their poorer homogeneity, and thus, lower precision of chemical fractionation results.


Assuntos
Cromo/análise , Monitoramento Ambiental/métodos , Sedimentos Geológicos/análise , Rios/química , Poluentes Químicos da Água/análise , Fracionamento Químico , Resíduos Industriais/análise , Polônia , Curtume
9.
Soft Matter ; 15(30): 6160-6170, 2019 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-31317157

RESUMO

We investigate by time-resolved synchrotron ultra-small X-ray scattering the dynamics of liquid-liquid phase-separation (LLPS) of gluten protein suspensions following a temperature quench. Samples at a fixed concentration (237 mg ml-1) but with different protein compositions are investigated. In our experimental conditions, we show that fluid viscoelastic samples depleted in polymeric glutenin phase-separate following a spinodal decomposition process. We quantitatively probe the late stage coarsening that results from a competition between thermodynamics that speeds up the coarsening rate as the quench depth increases and transport that slows down the rate. For even deeper quenches, the even higher viscoelasticity of the continuous phase leads to a "quasi" arrested phase separation. Anomalous phase-separation dynamics is by contrast measured for a gel sample rich in glutenin, due to elastic constraints. This work illustrates the role of viscoelasticity in the dynamics of LLPS in protein dispersions.


Assuntos
Fracionamento Químico/métodos , Glutens/isolamento & purificação , Viscosidade , Glutens/química , Espalhamento de Radiação , Síncrotrons , Temperatura Ambiente
10.
Food Chem ; 300: 125185, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31326673

RESUMO

Bioactive compounds should be extracted using alternative solvents and enabling technologies, in accordance with green extraction principles. The aim of this study is to develop an eco-friendly extraction method for grape-pomace anthocyanins on a larger scale. From a preliminary screening of 8 different natural deep eutectic solvents (NADES), a combination of choline chloride:citric acid was selected because of its price, physicochemical properties, and anthocyanin recovery and stability. The effects of multimode-microwave (MW), and low-frequency-ultrasound (US) irradiation (used alone or simultaneously), as well as that of process parameters on extraction efficiency have been investigated in order to maximise anthocyanin extraction yield. The best conditions were found to be: simultaneous ultrasound/microwave-assisted extraction (UMAE) (MW power at 300 W, US power 50 W), for 10 min with 30% (v/v) of water. This gave 1.77 mg gdw-1 of anthocyanins. Anthocyanins were efficiently recovered from NADES, which were recycled. The optimised procedure was scaled up to a half-litre batch.


Assuntos
Antocianinas/isolamento & purificação , Fracionamento Químico/métodos , Solventes/química , Vitis/química , Micro-Ondas , Extratos Vegetais/química , Ultrassom
11.
Food Chem ; 300: 125188, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31336274

RESUMO

An effective, simple and sensitive analytical method has been developed employing liquid chromatography coupled with tandem mass spectrometry and validated for estimation of five organophosphate pesticides at trace levels in six fruits and twelve vegetables. Plackett-Burman design and central composite design was used to screen and optimize the significant factors in modified QuEChERS (quick, easy, cheap, effective, rugged and safe) extraction method. The method evaluation was done by matrix-matched calibration with linearity ranging from 5 to 500 µg/L with a correlation coefficient more than 0.990. The detection and quantification limit ranged from 0.1 to 1.0 µg/kg and 0.5 to 5 µg/kg, respectively. The mean recoveries were in the range of 76.89-110.30 % with the relative standard deviation less than 13.26% for all pesticides. Further, the method developed was applied to analyze real samples cultivated in the hill areas of Nilgiris, South India.


Assuntos
Fracionamento Químico/métodos , Contaminação de Alimentos/análise , Organofosfatos/análise , Praguicidas/análise , Calibragem , Cromatografia Líquida/métodos , Análise de Alimentos/métodos , Frutas/química , Índia , Análise Multivariada , Organofosfatos/isolamento & purificação , Resíduos de Praguicidas/análise , Resíduos de Praguicidas/isolamento & purificação , Praguicidas/isolamento & purificação , Sensibilidade e Especificidade , Espectrometria de Massas em Tandem/métodos , Verduras/química
12.
Food Chem ; 300: 125200, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31325748

RESUMO

Ethyl carbamate (EC) and N-nitrosoamines (NAs) are toxic contaminants which can be typically formed in fermented alcoholic beverages. In the present work, a novel approach for simultaneous analysis of EC and NAs in beer and yellow rice wine based on ice-bath assisted sodiumhydroxide purification and GC-MS/MS was firstly established. Samples were extracted with acetonitrile-ethyl acetate after addition of internal standards. The extraction solution system was purified by sodiumhydroxide solid under ice-bath. After concentration, target analytes were separated on a HP-INNOWAX quartz capillary column and determined under dynamic multiple reactions monitoring mode of MS/MS. The limits of detection and quantification (LOD and LOQ), matrix effect, recovery and precision of the method were evaluated. Results were linear in the concentration range 2-200 µg/L for all analytes of interest, with regression coefficients higher than 0.999. LODs and LOQs were in the ranges of 0.1-0.5 µg/kg and 0.5-1.5 µg/kg, respectively. The mean recoveries at three spiked levels were between 81.5% and 121.0%. The intra- and inter-day precisions were in the ranges of 2.2-9.4% and 1.6-7.9%, respectively. The validated method was successfully applied to determine thirteen targets in commercial beer and yellow rice wine. EC was detected in all beers and yellow rice wines with the concentrations ranging from 1.18 to 22.90 µg/L. Results indicated wide EC contamination and confirmed its urgency for monitoring EC in fermented alcoholic beverages.


Assuntos
Cerveja/análise , Contaminação de Alimentos/análise , Nitrosaminas/análise , Uretana/análise , Vinho/análise , Acetonitrilos/química , Fracionamento Químico/métodos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Gelo , Limite de Detecção , Oryza , Reprodutibilidade dos Testes , Hidróxido de Sódio/química , Espectrometria de Massas em Tandem/métodos
13.
Fitoterapia ; 137: 104270, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31326418

RESUMO

As the important component of humus, fulvic acids (FA) have a good antidiarrhoeal effect on animals and humans, and have been worldwide used in animal husbandry and even clinical practice for a long time. Due to the extremely complex chemical composition and structure of FA, the material basis and mechanism of its antidiarrhoeal activity have not been fully elucidated. In this study, we used ultrafiltration technique to fractionate this heterogeneous mixture into a series of relatively uniform fractions. The main structural features of FA and its fractions were characterized, and at the same time their antidiarrhoeal activities on drug-induced diarrhoea model mice were evaluated and the collagen content in the intestine of mice were determined. Through contrastive study of the relative variations between structure characteristics and antidiarrhoeal activities with the change of molecular weight, we found that the oxygen-containing functional groups especially phenolic hydroxyl groups, molecular weight distribution, colloidal properties and astringency were the material basis of the antidiarrhoeal activity. Fulvic acid substances had a dual antidiarrhoeal mechanism acting on the intestinal mucosa. The components with low molecular weight (< 5 K) mainly acted on the inside of intestinal mucosa and the components with high molecular weight (> 5 K) acted on the surface, and they could simultaneously exert the antidiarrhoeal effects.


Assuntos
Antidiarreicos/farmacologia , Benzopiranos/farmacologia , Diarreia/tratamento farmacológico , Mucosa Intestinal/efeitos dos fármacos , Animais , Fracionamento Químico , Diarreia/induzido quimicamente , Masculino , Camundongos , Peso Molecular
14.
Bioresour Technol ; 289: 121708, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31271914

RESUMO

This study investigated simultaneous lignocellulose fractionation and conversion in a one-pot reaction using an aqueous choline chloride/methyl isobutyl ketone (ChCl/MIBK) biphasic solvent system. Under the optimized condition (170 °C, 60 min, 0.6 wt% H2SO4, 10.7 wt% solid loading), the biphasic solvent solubilized 96% xylan in raw switchgrass, which was simultaneously converted to furfural with a yield of 84.04%. The biphasic solvent was also able to selectively extract lignin, which had a high purity (93.1%), and uncondensed moieties (i.e., Hibbert's ketone), as well as decreased molecular weight and polydispersity index. The resultant pulp was enriched with cellulose (73.3%), which can be completely hydrolyzed into glucose within 48 h via enzymatic hydrolysis. Aqueous ChCl was successfully recycled and reused for atleast three cycles with similar performance in switchgrass fractionation. This study demonstrated that aqueous ChCl/MIBK biphasic system was an effective solvent system for co-production of furfural, high quality technical lignin and digestible cellulose for further upgrading.


Assuntos
Biomassa , Furaldeído/metabolismo , Lignina/metabolismo , Fracionamento Químico , Colina/química , Glucose/metabolismo , Hidrólise , Metil n-Butil Cetona/química , Panicum/metabolismo , Solventes
15.
Ying Yong Sheng Tai Xue Bao ; 30(6): 1840-1846, 2019 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-31257754

RESUMO

We used two types of soil with different physicochemical properties (loam and sand), oven-dried them, and then added the known isotopic composition mineral water that was reference water to compose the soil-water mixture with different soil water contents (loam: 0.15, 0.20, 0.30 g·g-1; sand: 0.10 g·g-1). After that, we set up different equilibrium time (loam: 3, 6, 12, 24, 48, 72, 96 h; sand: 96 h) to ensure that the dry soil particles were well mixed with the added water. The soil water was extracted by mechanical centrifugation and cryogenic vacuum extraction after equilibrium, and their isotope composition was analyzed. Results showed that the isotopic values of soil water extracted by mechanical centrifugation method had no significant difference in same water content with different equilibration times, but were more enriched compared with the reference water isotopic value. The maximum enrichment for hydrogen and oxygen isotope was 7.38‰ and 1.24‰, respectively. In contrast, cryogenic vacuum extraction method resulted in more depleted soil water isotopes than reference water, with the maximum depletion for hydrogen and oxygen isotope being 6.27‰ and 1.03‰, respectively. Moreover, the degree of depletion increased with the increases of equilibrium time (less than 24 h) at low water content, and became stable after 24 h. With the increases of soil water content, the isotopic composition of the extracted soil water was less affected by the two extraction methods. The water isotope value of loam that had high clay content, was more sensitive to the extraction method than the sandy soil that had low clay content. The difference of isotopic composition caused by extraction methods did not affect the plant water source segmentation.


Assuntos
Fracionamento Químico/métodos , Plantas/química , Solo/química , Água , Deutério , Isótopos de Oxigênio/análise
16.
Food Chem ; 299: 125144, 2019 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-31323440

RESUMO

Magnetic nanoparticles were synthesised to extract Sudan dyes from chilli powders. The adsorbents used were magnetic ferroferric oxide nanoparticles coated with polystyrene. The extraction procedures for Sudan dyes comprised liquid-solid extraction and magnetic solid phase extraction. The conditions were optimised to achieve efficient magnetic solid phase extraction, including extraction and desorption time, type and volume of the desorption solvent, and the mass of the adsorbents. Repeatability tests showed satisfactory recovery rates of 80.2-115.8%, with a relative standard deviation <3.8%. The results suggested that the proposed extraction method was effective and efficient to extract Sudan dyes from chilli powders. The extraction process was simpler compared with traditional approaches because the adsorbents can be rapidly removed from the sample matrix using a permanent magnet. The use of recyclable adsorbents decreased the cost greatly. Chilli powder samples collected from local markets in Singapore were tested using the proposed method under optimum conditions.


Assuntos
Capsicum/química , Corantes/análise , Contaminação de Alimentos/análise , Nanopartículas de Magnetita/química , Compostos Azo/análise , Fracionamento Químico/métodos , Cromatografia Líquida de Alta Pressão , Análise de Alimentos/instrumentação , Análise de Alimentos/métodos , Pós/química , Reprodutibilidade dos Testes , Singapura , Extração em Fase Sólida/instrumentação , Extração em Fase Sólida/métodos
17.
J Chromatogr A ; 1603: 433-437, 2019 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-31288929

RESUMO

An efficient strategy for the selection of active components based on counter-current fractionation and bioassay-guided separation was established in the present work. Blaps rynchopetera Fairmaire was an edible medicinal insect. Its extract showed the potential RAW264.7 macrophage cell inhibitory activity. After extraction with different solvents, the active components were enriched in ethyl acetate. In order to further track the active compounds, the ethyl acetate extraction was divided into 14 fractions by means of HSCCC. The results showed that the activities of F6 and F7 were significant higher than the others. Two compounds, hydroxytyrosol and 4-ethylbenzene-1,3-diol, were separated from the mixture of F6 and F7 by column chromatography and their chemical structures were confirmed by MS, 1H NMR and 13C NMR. The IC50 of hydroxytyrosol and 4-ethylbenzene-1,3-diol against RAW264.7 macrophage cell were 38.24 ±â€¯0.26 µg/mL and 103.26 ±â€¯0.29 µg/mL, respectively, indicating that hydroxytyrosol was the major active ingredient responsible for the RAW264.7 inhibitory activity of Blaps rynchopetera Fairmaire.


Assuntos
Bioensaio/métodos , Distribuição Contracorrente/métodos , Insetos/química , Animais , Fracionamento Químico , Cromatografia Líquida de Alta Pressão , Camundongos , Extratos Vegetais/farmacologia , Células RAW 264.7 , Solventes/química
18.
Bioresour Technol ; 291: 121799, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31351375

RESUMO

The aim of this work is to develop a novel green solvent based sustainable process to refine lignin into low molecular weight (LMW) and high molecular weight (HMW) fractions. Lignin dispersity reduction were experimentally determined using four solvent mixtures, and benchmarked against eight pure solvents. Data outputs were used for modelling the integrated fractionation process. Dispersity reduction of up to 73% was achieved for the high value LMW fraction. Also, a 90% reduction of energy requirement was achieved with an optimized process incorporating a mechanical vapor compression system. This study showed that solvent mixtures involving water can significantly reduce the cost, environment, health and safety impacts of lignin fractionation. Techno-economic evaluation confirmed the economic viability of a large-scale process processing 50 tonne/day of lignin.


Assuntos
Lignina/química , Fracionamento Químico , Peso Molecular , Solventes
19.
Environ Pollut ; 253: 19-28, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31302399

RESUMO

We studied the size distribution of ions (Cl-, NO3-, SO4=, Na+, NH4+, K+, Mg++, Ca++) and elements (As, Ba, Cd, Co, Cs, Cu, Fe, Li, Mn, Ni, Pb, Rb, Sb, Se, Sn, Sr, Ti, Tl, V, Zn) during the winter and summer seasons of seven consecutive years (2008-2014) in an area of the Po Valley (Northern Italy) characterised by industrial, agricultural and urban settings. The study included the collection and analysis of 41 series of size-segregated samples (MOUDI sampler, 10 stages, cut sizes from 0.18 to 18 µm). Ions were analysed by ion chromatography; elemental analysis was carried out by ICP-MS, by applying a chemical fractionation method able to increase the selectivity of PM source tracers. Our results indicate that important winter/summer variations occurred in both the concentration and size distribution of most PM components. These variations were explained in terms of variations in the strength of the prevailing sources of each component. The contribution of biomass burning for domestic heating was highlighted by the well-known tracer K+ but also by the soluble fraction of Rb, Cs and Li. Biomass burning contribution to atmospheric PM was mostly contained in the fine fraction, with a broad size-distribution from 0.18 to 1.8 µm. This source also appreciably increased the concentration of other elements in fine PM (As, Cd, Co, Mn, Pb, Sb, Sn). A few PM components (tracers of sea-spray, brake lining and some industries) did not show marked seasonal variations in concentration and size distribution. However, during winter, for brake lining and industry tracers we observed an upward shift in the dimension of fine particles and a downward shift in the dimension of coarse particles, due to the ageing of the air masses.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental , Material Particulado/análise , Aerossóis/análise , Envelhecimento , Fracionamento Químico , Calefação , Indústrias , Íons/análise , Itália , Peso Molecular , Tamanho da Partícula , Estações do Ano
20.
J Sci Food Agric ; 99(14): 6546-6551, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31328269

RESUMO

BACKGROUND: Proteins recovery using hydrochloric acid (HCl) in acid-aided solubilization could cause greater loss in its functionality over alkali-aided solubilization. Moreover, using HCl in edible foods is also a health concern. Replacing HCl with organic acids for acid-aided solubilization could address these problems. The aim was to study the effect of organic acid (glacial acetic acid) as a replacement for HCl during pH shift processing on the characteristics and functionality of rohu (Labeo rohita) protein isolates. Rohu proteins were obtained by solubilizing at pH 3.0 and pH 11.0 using glacial acetic acid and sodium hydroxide (10 mol L-1 ). RESULTS: Results showed that solubilization at pH 11.0 gave higher protein yields (766.8 ± 2.4 g kg-1 ) compared to solubilization at pH 3.0 (735.7 ± 7.1 g kg-1 ) (P < 0.05). Isolates from acid-aided solubilization had higher whiteness and total pigment content over isolates obtained by alkali-aided solubilization. Rohu isolates recovered by alkaline solubilization showed higher water and oil holding capacity, gel strength, folding scores, foaming and emulsion capacity than acid processed isolates (P < 0.05). Solubilization of rohu proteins using glacial acetic acid produced isolates with low breaking force (149.0 g), low storage modulus (G') values and low folding test score (1.0) over the alkaline isolates (P < 0.05). CONCLUSION: Results indicated that, recovering rohu proteins using organic acid (glacial acetic acid) could produce isolates with poor functional properties, while using the organic acid to precipitate the proteins solubilized by alkali-aided processing could produce proteins with better yields and functionality. © 2019 Society of Chemical Industry.


Assuntos
Fracionamento Químico/métodos , Proteínas de Peixes/isolamento & purificação , Manipulação de Alimentos/métodos , Ácido Acético/química , Animais , Cyprinidae , Proteínas de Peixes/química , Concentração de Íons de Hidrogênio , Solubilidade
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