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1.
Food Res Int ; 173(Pt 1): 113220, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37803538

RESUMO

Grape pomace is the main solid residue of wine industry, containing high amounts of phenolic compounds. Considering its high potential, an extraction procedure was optimized for maximal recovery of anthocyanins from grape pomace (Vitis vinifera L.) using citric acid as a generally recognized as safe (GRAS) acidulant in water. Volume of solvent (3.2-36.8 mL), time (14.4-165.6 min) and pH of solvent (1.12-4.48) were the studied variables. Furthermore, the best condition to obtain extract rich in anthocyanins was submitted to the gravitational block freeze concentration process. The performance of the process was evaluated and cryoconcentrated and ice fractions were analyzed for physicochemical properties, bioactive compounds content, and antioxidant activity. Interaction, linear, and quadratic effects for volume and pH of solvent were significant by analysis of variance (ANOVA). The experimental design allowed the prediction for maximal recovery of anthocyanins (10 mL of solvent at pH 1.8). The bioactive composition of the optimized grape pomace extract was influenced by the cryoconcentration process. After three cycles using gravitational block freeze concentration, the total phenolics and monomeric anthocyanins were approximately 4 and 5 times higher than the initial condition of the extract, respectively. Consequently, an increase in antioxidant activity was observed. The increase in the concentration of bioactive compounds reached a process efficiency of 93% (stage 1) for phenolic compounds and 91% (stage 2) for anthocyanins. Therefore, the final water-based optimized method is safe and has a low cost and the concentrated extract certainly showed higher concentrations of total phenolics and anthocyanins, compared to the initial extract. The proposed clean extraction method and cryoconcentration technique can be considered important strategies for recovering and valuing grape pomace components, improving the approach to the circular economy concept in the wine industry.


Assuntos
Vitis , Vinho , Antocianinas/análise , Vinho/análise , Antioxidantes/análise , Vitis/química , Fenóis/análise , Extratos Vegetais/química , Solventes/análise , Água/análise
2.
Food Res Int ; 173(Pt 1): 113266, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37803579

RESUMO

In this study, different Deep Eutectic Solvents based on choline chloride ([Ch]Cl) with carboxylic acids, sugars, and glycerol, were investigated as alternative solvents for the extraction of flavonoids from soybean and okara. Initially, the COSMO-SAC was investigated as a tool in solvent screening for the extraction of flavonoids. Experimental validation was performed using total flavonoid analysis with the solvents that showed greater interaction with the solutes. The extracts obtained from soybean and okara using the DES [Ch]Cl:acetic acid added with 30 % water showed the highest total flavonoid content, 1.05 mg eq. of catechin/g dry soybean and 0.94 mg eq. of catechin /g dry okara, respectively. For phenolic compound extraction, [Ch]Cl: acetic acid DES extracted approximately 1.16 mg GAE/g of soybean and 0.69 mg GAE/g of okara. For antioxidant activity, soybean and okara extracts obtained with [Ch]Cl: acetic acid showed FRAP results of 0.40 mg Trolox/mL of extract and 0.45 mg Trolox/mL of extract, respectively. In addition, the isoflavones daidzein, genistein, glycitein, daidzin, genistin, and glycitin were identified and quantified in the soybean and okara extracts obtained with DES [Ch]Cl: acetic acid with 30% water, totaling 1068.05 and 424.32 µg total isoflavones/g dry sample. Therefore, The COSMO-SAC model was a useful tool in solvent screening, saving time and costs. Also, DES can be an alternative solvent for extracting flavonoids to replace conventional organic solvents, respecting current environmental and human health concerns.


Assuntos
Catequina , Isoflavonas , Humanos , Flavonoides/análise , Glycine max , Solventes Eutéticos Profundos , Extratos Vegetais/análise , Isoflavonas/análise , Solventes/análise , Água , Acetatos
3.
J Anal Toxicol ; 47(7): 580-587, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37506044

RESUMO

There is an increasing number of people affected worldwide by mental health disorders, such as depression and anxiety. One of the main courses of treatment, along with psychotherapy, is the use of psychoactive medications, like antidepressants and benzodiazepines. Also, the unprescribed use of these substances is a concerning public health issue. Hence, the analysis of psychotropic medications is mandatory in postmortem toxicology and various biological samples can be used for this detection, among them the vitreous humor (VH) stands out. Also, there is a demand for more sustainable and more efficient extraction methodologies according to green chemistry. An example is solid phase microextraction techniques (SPME), which use a solid sorbent and small solvent amounts. Biosorbents are substances of natural origin with sorptive properties, and they have been successfully used in SPME in environmental toxicology for water analysis, mainly. This study aimed to develop a sustainable, fast, cheap and simple SPME methodology using cork sheet strips as a biosorbent, to extract antidepressants, benzodiazepines and others from VH samples by liquid chromatography coupled to tandem mass spectrometry. The extraction was conducted in a 96-well plate using 200 µL of VH and optimization of relevant parameters for extraction was performed. For solvent optimization, two simplex-centroid experiments were planned for extraction and desorption and to evaluate time and pH, a Doehlert design experiment was performed. The analytical method for the determination and quantification of 17 substances was validated. The quantification limits were 5 ng/mL for all analytes and the calibration curves were linear between 5 and 30 ng/mL. This study was able to develop an efficient, cheap, simple and fast microextraction method for 17 analytes in VH, using strips of cork sheet for extraction and a 96-well plate as a container. Furthermore, this approach system could be automated for routine toxicology laboratories.


Assuntos
Microextração em Fase Sólida , Corpo Vítreo , Humanos , Toxicologia Forense , Corpo Vítreo/química , Microextração em Fase Sólida/métodos , Psicotrópicos/análise , Solventes/análise , Benzodiazepinas/análise
4.
Anal Bioanal Chem ; 415(16): 3073-3091, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37085739

RESUMO

Toxic elements represent a serious threat to the environment and cause harmful effects on different environmental components, even at trace levels. These toxic elements are often difficult to detect through the typical instrumentation of an analytical laboratory because they are found at very low concentrations in matrices such as food and water. Therefore, preconcentration plays a fundamental role since it allows the effects of the matrix to be minimized, thus reaching lower detection limits and greater sensitivity of detection techniques. In recent years, solid-phase extraction has been successfully used for the preconcentration of metals as an environmentally friendly technique due to the fact that it eliminates or minimizes the use of reagents and solvents and offers reduced analysis times and low generation of waste in the laboratory. Hybrid biomaterials are low-cost, eco-friendly, and useful as efficient solid phases for the preconcentration of elements. In this review, recent investigations based on the use of hybrid biomaterials for the preconcentration and determination of toxic metals are presented and discussed, given special attention to bionanomaterials. A brief description of hybrid biomaterials often used for analytical purposes, as well as analytical techniques mostly used to characterize the hybrid biomaterials, is explained. Finally, the future prospects that encourage the search for new hybrid biomaterials are commented upon.


Assuntos
Metaloides , Metais/toxicidade , Metais/análise , Água , Solventes/análise , Extração em Fase Sólida/métodos
5.
Molecules ; 28(5)2023 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-36903602

RESUMO

Jabuticaba (Plinia cauliflora) and jambolan (Syzygium cumini) fruits are rich in phenolic compounds with antioxidant properties, mostly concentrated in the peel, pulp, and seeds. Among the techniques for identifying these constituents, paper spray mass spectrometry (PS-MS) stands out as a method of ambient ionization of samples for the direct analysis of raw materials. This study aimed to determine the chemical profiles of the peel, pulp, and seeds of jabuticaba and jambolan fruits, as well as to assess the efficiency of using different solvents (water and methanol) in obtaining metabolite fingerprints of different parts of the fruits. Overall, 63 compounds were tentatively identified in the aqueous and methanolic extracts of jabuticaba and jambolan, 28 being in the positive ionization mode and 35 in the negative ionization mode. Flavonoids (40%), followed by benzoic acid derivatives (13%), fatty acids (13%), carotenoids (6%), phenylpropanoids (6%), and tannins (5%) were the groups of substances found in greater numbers, producing different fingerprints according to the parts of the fruit and the different extracting solvents used. Therefore, compounds present in jabuticaba and jambolan reinforce the nutritional and bioactive potential attributed to these fruits, due to the potentially positive effects performed by these metabolites in human health and nutrition.


Assuntos
Myrtaceae , Syzygium , Humanos , Syzygium/química , Frutas/química , Solventes/análise , Myrtaceae/química , Antioxidantes/análise , Extratos Vegetais/química , Espectrometria de Massas em Tandem
6.
Vet Res Commun ; 47(3): 1273-1283, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36729277

RESUMO

Physic nut Jatropha curcas cake/meal obtained after oil extraction has a high protein content, however, the presence of antinutrients (trypsin inhibitor, lectin and phytate) and toxic compounds (phorbol esters) limit their use as an alternative feedstuff. Thus, the detoxification process in cake/meal is necessary to allow their inclusion in fish diets. The present study aimed to evaluate the effects of solvent and extrusion-treated jatropha cake (SETJC) in Nile tilapia (Oreochromis niloticus) diets on growth, body composition, nutrient utilization, metabolic and hematological responses, and digestibility of experimental diets. Five experimental diets were formulated to be isonitrogenous (28.50% digestible protein) and isoenergetic (13.39 MJ/kg digestible energy) with graded levels of SETJC (0, 3, 6, 9, and 12%). The experimental design was completely randomized with five treatments and four replicates. The detoxification treatments reduced the phorbol esters (PE) of jatropha cake by 96% (0.58 mg/g of PE before and 0.023 mg/g of PE after treatments). Increased levels of SETJC depressed growth, feed efficiency, and protein digestibility. A similar trend was observed for hematological and biochemistry parameters. Aspartate and alanine aminotransferase, as well as phosphorus and magnesium concentrations in the fillets, increased at the highest levels of SETJC. Thus, the data of the present study suggests that the residual content, different structural forms of phorbol ester and its biological activity, as well as some antinutritional factors, can influence negatively the growth, metabolism and digestibility of experimental diets for Nile tilapia.


Assuntos
Ciclídeos , Jatropha , Animais , Jatropha/química , Jatropha/metabolismo , Ração Animal/análise , Solventes/análise , Dieta/veterinária , Ésteres de Forbol/farmacologia , Ésteres de Forbol/análise , Ésteres de Forbol/metabolismo , Sementes/química , Sementes/metabolismo
7.
Molecules ; 28(3)2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36771071

RESUMO

Tobacco cultivation and industrialization are characterized by the production of trillions of pre-harvest and post-harvest waste biomasses each year with the resulting negative effects on the environment. The leaves of blunt, pre-harvest waste, could be further used to obtain bioactive metabolites, i.e., polyphenols and alkaloids, for its potential cosmetic use. This study was conducted to obtain bio-compounds from pre-harvest tobacco leaf waste (var. Virginia) by applying conventional and green solvents (NaDES). Leaves and ground leaf waste were characterized based on their microscopic features. Conventional solvents, such as water, acetone, ethanol, and non-conventional solvents, such as Natural Deep Eutectic Solvents (NaDES), i.e., sucrose:lactic acid (LAS), frutose:glucose:sucrose (FGS), lactic acid:sucrose:water (SALA), choline chloride:urea (CU), and citric acid: propylene glycol (CAP) were used for bioactive extraction from tobacco waste powder. CU, FGS, and acetone/ethanol had similar behavior for the best extraction of alkaloids (6.37-11.23 mg ACE/g tobacco powder). LAS, FGS, SALA, and CU were more effective in phenolic compound extraction than conventional solvents (18.13-21.98 mg AGE/g tobacco powder). Because of this, LAS and SALA could be used to obtain phenolic-enriched extracts with lower alkaloid content rather than CU and FGS. Extracts of the powder obtained with conventional solvent or CU showed a high level of sugars (47 mg/g tobacco powder) The ABTS antioxidant capacity of tobacco leaf powder was higher in the extracts obtained with CU, FGS, and acetone (SC50 1.6-5 µg GAE/mL) while H2O2 scavenging activity was better in the extracts obtained with LAS, CAP and SALA (SC50 3.8-8.7 µg GAE/mL). Due to the biocompatibility of the NaDES with the components of tobacco leaf waste, the opportunity to apply these extracts directly in antioxidant formulations, such as cosmetics, phytotherapic, and other formulations of topic use seems promising. Furthermore, NaDES constituents, i.e., urea and organic acid can also have beneficial effects on the skin.


Assuntos
Alcaloides , Nicotiana , Acetona , Antioxidantes/análise , Solventes Eutéticos Profundos , Etanol , Peróxido de Hidrogênio , Fenóis , Extratos Vegetais/análise , Folhas de Planta/química , Pós , Propilenoglicol , Solventes/análise , Nicotiana/química , Água
8.
Integr Environ Assess Manag ; 19(3): 698-705, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36189835

RESUMO

The literature on the presence of microplastics (MPs) and their potential impact on terrestrial ecosystems is still scarce. Interestingly, soil MPs are detected as organic carbon (SOC) using traditional quantification methods (e.g., loss on ignition [LOI]), although its dynamics in the environment will be different. The objective of this study was to quantify the carbon (C) contribution of MPs to the SOC in superficial soil samples from a coastal urban wetland (Avellaneda, Buenos Aires, Argentina) with the features of a humid subtropical forest and compare with hydrocarbon contribution. Soil samples were split for analysis of moisture content; texture (sieve and pipet method); organic matter as a LOI (8 h at 450 °C); total hydrocarbons (THCs; gravimetry of solvent extractable matter); n-alkanes (solvent extraction and gas chromatography-flame ionization detection analysis); and extraction of MPs (floatation in NaClaq , filtration, H2 O2 digestion, and visual sorting under a stereomicroscope). The superficial soil was a sandy clay loam with a large organic matter content (19%-30%). The THC averaged 2.5 ± 1.9 g kg and the marked predominance of odd-numbered carbon n-alkanes maximizing at C29 and C31 show the contribution of the terrestrial plant waxes. The average number of MPs was 587 ± 277 items kg of dry soil, predominantly fibers. Taking account of the C content, THCs and MPs add to the soil 1.23 ± 1.10 ton C ha and 0.10-0.97 ton C ha, respectively. Therefore, in this system with humid forest characteristics, the MPs represent between 0.12% and 1.25% of soil estimated carbon, in a magnitude similar to the C contribution of THCs (0.6%-4.2%). This preliminary study shows the relevance of discriminating MPs from other carbon sources and presents a description of their impact on soils to advance future research or tools for decision-makers. Integr Environ Assess Manag 2023;19:698-705. © 2022 SETAC.


Assuntos
Microplásticos , Solo , Plásticos , Carbono/análise , Ecossistema , Hidrocarbonetos , Alcanos/análise , Solventes/análise
9.
Molecules ; 27(24)2022 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-36557786

RESUMO

A new sorbent material based on modified clay with ionic liquid immobilized into an agarose film was developed as part of this study. It was applied to determine organochlorine pollutants, like disinfection byproducts, through headspace solid-phase microextraction-gas chromatography-electron capture detection (HS-SPME-GC-ECD). The disinfection byproducts determined in this study were used as model molecules because they were volatile compounds, with proven severe effects on human health. Their presence in aquatic environments is in trace concentrations (from pg L-1 to mg L-1). They are classified as emergent pollutants and their determination is a challenge for analytical chemists. The parameters which affected the extraction efficiency, i.e., number and distance between SPME discs, salt concentration, the temperature of extraction, extraction time, and desorption time, were optimized. A wide linear dynamic range of 10-1000 ng mL-1 and coefficients of determination better than 0.997 were achieved. The limits of detection and the limits of quantitation were found in the ranges of (1.7-3.7) ng mL-1 and (5.6-9.9) ng mL-1, respectively. The precision, expressed as relative standard deviation (RSD), was better than 8%. The developed sorbent exhibits good adsorption affinity. The applicability of the proposed methodology for the analysis of trihalomethanes in environmental and water samples showed recoveries in the range of 86-95%. Finally, the newly created method fully complied with the principles of green chemistry. Due to the fact that the sorbent holder was made of agarose, which is a wholly biodegradable material, sorbent clay is a widespread material in nature. Moreover, the reagents intercalated into the montmorillonite are new green solvents, and during the whole procedure, low amounts of organic solvents were used.


Assuntos
Microextração em Fase Sólida , Poluentes Químicos da Água , Humanos , Microextração em Fase Sólida/métodos , Trialometanos/análise , Argila , Sefarose , Água/análise , Solventes/análise , Poluentes Químicos da Água/análise , Reprodutibilidade dos Testes
10.
J Forensic Leg Med ; 91: 102434, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36191450

RESUMO

The use of vitreous humor (VH) in forensic casework has been growing in the last years due to numerous advantages. Several compounds can be evaluated in this matrix, including benzodiazepines whose determination is essential due to their great availability and potential of dependance and misuse. Postmortem toxicological analyses are required to determine the influence of benzodiazepines in deaths. However, most of the analytical methods which determine these drugs in VH are laborious and time consuming. This article describes a simple method based on protein precipitation for the determination of eight benzodiazepines in VH samples. Samples were prepared through a protein precipitation method and analyzed by liquid chromatography tandem mass spectrometry. Solvent choice and sample and solvent volumes for precipitation were optimized using chemometric approaches. The method was validated for selectivity, lower limit of quantification (LLOQ), linearity, carryover, precision, bias, matrix effect and dilution integrity. In order to verify the applicability, 62 vitreous humor samples were analyzed. LLOQs were 1 ng/mL and calibration curves were linear from 1 to 25 ng/mL (r2 > 0,99) for all analytes. Bias, precision and dilution integrity results were satisfactory according to proper guidelines. Ionization suppression was significant with values ranging from 8 to 37%. Two samples from real cases were positive for diazepam with the following concentrations: 6.80 ng/mL and 47.68 ng/mL, approximately 10 times lower than those found in peripheral blood. The procedure described here can be used as a straightforward and low cost method for the quantitation of multiple benzodiazepines in VH.


Assuntos
Benzodiazepinas , Espectrometria de Massas em Tandem , Benzodiazepinas/análise , Cromatografia Líquida/métodos , Diazepam/análise , Humanos , Reprodutibilidade dos Testes , Solventes/análise , Espectrometria de Massas em Tandem/métodos , Corpo Vítreo/química
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