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1.
Curr Protoc ; 1(9): e237, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34499805

RESUMO

Eukaryotic cells contain numerous membrane-bound and membraneless organelles that provide spatiotemporal control for diverse biological processes. The liquid-liquid phase separation of proteins has been proposed as the driving force behind the formation of membraneless organelles. Here, we describe a method to determine the phase separation activities of proteins in plants. This basic method includes protocols for an in vivo fluorescence recovery after photobleaching assay in Nicotiana benthamiana using transient expression, an in vitro liquid droplet reconstitution assay using purified recombinant proteins, and an in vivo fluorescence recovery after photobleaching assay in Arabidopsis thaliana using stable transgenic plants. With these assays, the phase separation characteristics of a protein can be determined. © 2021 Wiley Periodicals LLC. Basic Protocol 1: Detection of protein phase separation activities in N. benthamiana Support Protocol: Fluorescence recovery after photobleaching assay Basic Protocol 2: Detection of protein phase separation in vitro Basic Protocol 3: Detection of protein phase separation in stable transgenic Arabidopsis thaliana plants.


Assuntos
Fracionamento Químico/métodos , Organelas , Proteínas de Plantas , Fenômenos Biofísicos , Membranas
2.
Ultrason Sonochem ; 77: 105680, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34365154

RESUMO

The present study optimised the ultrasound-assisted extraction (UAE) of bioactive compounds from Amaranthus hypochondriacus var. Nutrisol. Influence of temperature (25.86-54.14 °C) and ultrasonic power densities (UPD) (76.01-273.99 mW/mL) on total betalains (BT), betacyanins (BC), betaxanthins (BX), total polyphenols (TP), antioxidant activity (AA), colour parameters (L*, a*, and b*), amaranthine (A), and isoamaranthine (IA) were evaluated using response surface methodology. Moreover, betalain extraction kinetics and mass transfer coefficients (KLa) were determined for each experimental condition. BT, BC, BX, TP, AA, b*, KLa, and A were significantly affected (p < 0.05) by temperature extraction and UPD, whereas L*, a*, and IA were only affected (p < 0.05) by temperature. All response models were significantly validated with regression coefficients (R2) ranging from 87.46 to 99.29%. BT, A, IA, and KLa in UAE were 1.38, 1.65, 1.50, and 29.93 times higher than determined using conventional extraction, respectively. Optimal UAE conditions were obtained at 41.80 °C and 188.84 mW/mL using the desired function methodology. Under these conditions, the experimental values for BC, BX, BT, TP, AA, L*, a*, b*, KLa, A, and IA were closely related to the predicted values, indicating the suitability of the developed quadratic models. This study proposes a simple and efficient UAE method to obtain betalains and polyphenols with high antioxidant activity, which can be used in several applications within the food industry.


Assuntos
Amaranthus/química , Antioxidantes/isolamento & purificação , Betalaínas/isolamento & purificação , Fracionamento Químico/métodos , Polifenóis/isolamento & purificação , Ondas Ultrassônicas , Fatores de Tempo
3.
Molecules ; 26(16)2021 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-34443623

RESUMO

Phenolic compounds have long been of great importance in the pharmaceutical, food, and cosmetic industries. Unfortunately, conventional extraction procedures have a high cost and are time consuming, and the solvents used can represent a safety risk for operators, consumers, and the environment. Deep eutectic solvents (DESs) are green alternatives for extraction processes, given their low or non-toxicity, biodegradability, and reusability. This review discusses the latest research (in the last two years) employing DESs for phenolic extraction, solvent components, extraction yields, extraction method characteristics, and reviewing the phenolic sources (natural products, by-products, wastes, etc.). This work also analyzes and discusses the most relevant DES-based studies for phenolic extraction from natural sources, their extraction strategies using DESs, their molecular mechanisms, and potential applications.


Assuntos
Produtos Biológicos/química , Fracionamento Químico/métodos , Fenóis/isolamento & purificação , Solventes/química
4.
Molecules ; 26(16)2021 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-34443587

RESUMO

Panax spp. (Araliaceae family) are widely used medicinal plants and they mainly include Panax ginseng C.A. Meyer, Panax quinquefolium L. (American ginseng), and Panax notoginseng (notoginseng). Polysaccharides are the main active ingredients in these plants and have demonstrated diverse pharmacological functions, but comparisons of isolation methods, structural features, and bioactivities of these polysaccharides have not yet been reported. This review summarizes recent advances associated with 112 polysaccharides from ginseng, 25 polysaccharides from American ginseng, and 36 polysaccharides from notoginseng and it compares the differences in extraction, purification, structural features, and bioactivities. Most studies focus on ginseng polysaccharides and comparisons are typically made with the polysaccharides from American ginseng and notoginseng. For the extraction, purification, and structural analysis, the processes are similar for the polysaccharides from the three Panax species. Previous studies determined that 55 polysaccharides from ginseng, 18 polysaccharides from American ginseng, and 9 polysaccharides from notoginseng exhibited anti-tumor activity, immunoregulatory effects, anti-oxidant activity, and other pharmacological functions, which are mediated by multiple signaling pathways, including mitogen-activated protein kinase, nuclear factor kappa B, or redox balance pathways. This review can provide new insights into the similarities and differences among the polysaccharides from the three Panax species, which can facilitate and guide further studies to explore the medicinal properties of the Araliaceae family used in traditional Chinese medicine.


Assuntos
Fracionamento Químico/métodos , Panax/química , Polissacarídeos/química , Polissacarídeos/farmacologia , Animais , Humanos , Polissacarídeos/isolamento & purificação
5.
Molecules ; 26(16)2021 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-34443475

RESUMO

Different parts of a plant (seeds, fruits, flower, leaves, stem, and roots) contain numerous biologically active compounds called "phytoconstituents" that consist of phenolics, minerals, amino acids, and vitamins. The conventional techniques applied to extract these phytoconstituents have several drawbacks including poor performance, low yields, more solvent use, long processing time, and thermally degrading by-products. In contrast, modern and advanced extraction nonthermal technologies such as pulsed electric field (PEF) assist in easier and efficient identification, characterization, and analysis of bioactive ingredients. Other advantages of PEF include cost-efficacy, less time, and solvent consumption with improved yields. This review covers the applications of PEF to obtain bioactive components, essential oils, proteins, pectin, and other important materials from various parts of the plant. Numerous studies compiled in the current evaluation concluded PEF as the best solution to extract phytoconstituents used in the food and pharmaceutical industries. PEF-assisted extraction leads to a higher yield, utilizes less solvents and energy, and it saves a lot of time compared to traditional extraction methods. PEF extraction design should be safe and efficient enough to prevent the degradation of phytoconstituents and oils.


Assuntos
Fracionamento Químico/instrumentação , Fracionamento Químico/métodos , Técnicas Eletroquímicas/instrumentação , Técnicas Eletroquímicas/métodos , Compostos Fitoquímicos , Indústria de Processamento de Alimentos , Solventes/química , Tecnologia Farmacêutica
6.
Ultrason Sonochem ; 77: 105696, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34358883

RESUMO

A novel, green and eco-friendly, cost-effective, fast, and reliable high energy ultrasonication (US) extraction with UHPLC-MSMS (Ultrahigh performance liquid chromatography with mass spectrometry) quantification of Glycyrrhizic acid (GZA) is reported herein for the first time. The study provides useful insights regarding the effect of US-factors with statistical analysis and mechanisms, involved in GZA-extraction and analysis. An US-extraction method (US-MD) was developed using three levels of US factors: solvents (AC (acetone), EtOH (ethanol), H2O (water)), time (1, 2, 3 min), amplitudes (30, 40, 50%), pulse (10/0.5, 20/0.5, 30/0.5 sec), particle sizes (0.5, 1, 1.4 mm), and temperatures (20, 30, 40 °C). The US-MD was further validated with high accuracy 98.96 ± 6.82 and r2 = 0.995 whereas, an in-house analytical method (UHPLC-MSMS) was developed and validated to quantify the GZAamount. UHPLCMSMS-MD resulted in a retention time of 0.31 min with MSMS (821.400 > 351.200) in a 1 min run time whereas, UHPLCMSMS-MV showed high accuracy and precision with r2 = 0.998 for GZA. Statistical analysis of K-mean clustering finalized US-set-of-factors showing optimum extract yield (mg/1mg) of 0.48 with sum (2.41 ± 014) and mean (0.27) along with a high GZA-amount (µg/mg) of 8.23 with sum (43.31 ± 2.07) and mean (4.81) for H2O in 3 min at 40 °C using particle size (1.4 mm), amplitude (50%), and pulse (30/0.5). Large scale application of US-UHPLCMSMS confirmed the evaluation power of the method showing the order for GZA amount; Egypt > Pakistan > Syria > India > Palestine > America > Georgia > Morocco. A significant effect for US factors Vs extract yield and GZA amount was observed however, solvent*GZA-amount and extract yield*particle size were more significantly correlated compared to time*temperature*amplitude*pulse analyzed via PCA, GLM-UniANOVA, K-mean, and Pearson's correlation (P ≤ 0.05). A combined mechanism of shear stress, macroturbulence due to acoustic cavitation and implosions, sonochemical, and sonocapillary effect were noted for the US technique producing higher extract yield and GZA amount from licorice.


Assuntos
Fracionamento Químico/métodos , Cromatografia Líquida de Alta Pressão , Glycyrrhiza/química , Ácido Glicirrízico/análise , Ácido Glicirrízico/isolamento & purificação , Espectrometria de Massas em Tandem , Ondas Ultrassônicas , Química Verde , Fatores de Tempo
7.
Int J Mol Sci ; 22(16)2021 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-34445303

RESUMO

Macromolecular associates, such as membraneless organelles or lipid-protein assemblies, provide a hydrophobic environment, i.e., a liquid protein phase (LP), where folding preferences can be drastically altered. LP as well as the associated phase change from water (W) is an intriguing phenomenon related to numerous biological processes and also possesses potential in nanotechnological applications. However, the energetic effects of a hydrophobic yet water-containing environment on protein folding are poorly understood. Here, we focus on small ß-sheets, the key motifs of proteins, undergoing structural changes in liquid-liquid phase separation (LLPS) and also model the mechanism of energy-coupled unfolding, e.g., in proteases, during W → LP transition. Due to the importance of the accurate description for hydrogen bonding patterns, the employed models were studied by using quantum mechanical calculations. The results demonstrate that unfolding is energetically less favored in LP by ~0.3-0.5 kcal·mol-1 per residue in which the difference further increased by the presence of explicit structural water molecules, where the folded state was preferred by ~1.2-2.3 kcal·mol-1 per residue relative to that in W. Energetics at the LP/W interfaces was also addressed by theoretical isodesmic reactions. While the models predict folded state preference in LP, the unfolding from LP to W renders the process highly favorable since the unfolded end state has >1 kcal·mol-1 per residue excess stabilization.


Assuntos
Transição de Fase/efeitos dos fármacos , Conformação Proteica em Folha beta/efeitos dos fármacos , Água/farmacologia , Motivos de Aminoácidos/efeitos dos fármacos , Fracionamento Químico/métodos , Simulação por Computador , Interações Hidrofóbicas e Hidrofílicas/efeitos dos fármacos , Cinética , Substâncias Macromoleculares/química , Modelos Moleculares , Conformação Proteica/efeitos dos fármacos , Dobramento de Proteína/efeitos dos fármacos , Estabilidade Proteica/efeitos dos fármacos , Teoria Quântica , Viscosidade , Água/química
8.
Food Environ Virol ; 13(3): 303-315, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34296387

RESUMO

Wastewater surveillance of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is an emerging public health tool to understand the spread of Coronavirus Disease 2019 (COVID-19) in communities. The performance of different virus concentration methods and PCR methods needs to be evaluated to ascertain their suitability for use in the detection of SARS-CoV-2 in wastewater. We evaluated ultrafiltration and polyethylene glycol (PEG) precipitation methods to concentrate SARS-CoV-2 from sewage in wastewater treatment plants and upstream in the wastewater network (e.g., manholes, lift stations). Recovery of viruses by different concentration methods was determined using Phi6 bacteriophage as a surrogate for enveloped viruses. Additionally, the presence of SARS-CoV-2 in all wastewater samples was determined using reverse transcription quantitative PCR (RT-qPCR) and reverse transcription droplet digital PCR (RT-ddPCR), targeting three genetic markers (N1, N2 and E). Using spiked samples, the Phi6 recoveries were estimated at 2.6-11.6% using ultrafiltration-based methods and 22.2-51.5% using PEG precipitation. There was no significant difference in recovery efficiencies (p < 0.05) between the PEG procedure with and without a 16 h overnight incubation, demonstrating the feasibility of obtaining same day results. The SARS-CoV-2 genetic markers were more often detected by RT-ddPCR than RT-qPCR with higher sensitivity and precision. While all three SARS-CoV-2 genetic markers were detected using RT-ddPCR, the levels of E gene were almost below the limit of detection using RT-qPCR. Collectively, our study suggested PEG precipitation is an effective low-cost procedure which allows a large number of samples to be processed simultaneously in a routine wastewater monitoring for SARS-CoV-2. RT-ddPCR can be implemented for the absolute quantification of SARS-CoV-2 genetic markers in different wastewater matrices.


Assuntos
Fracionamento Químico/métodos , SARS-CoV-2/isolamento & purificação , Ultrafiltração/métodos , Águas Residuárias/química , Águas Residuárias/virologia , Precipitação Química , Monitoramento Ambiental , Polietilenoglicóis/química , Saúde Pública , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , SARS-CoV-2/genética , Esgotos/química , Esgotos/virologia , Proteínas Virais/genética , Poluição da Água/análise
9.
Ultrason Sonochem ; 76: 105638, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34225213

RESUMO

The aim of the present research was to develop green and sustainable extraction procedure for ß-carotene recovery from pumpkin. A series of hydrophobic natural deep eutectic solvents (NADESs) based onfatty acids were prepared to establish high extraction efficiency of ß-carotene and to increase stability of extracted carotenoids from the pumpkin. To intensify extraction process, NADES composed of C8 and C10 fatty acids (3:1) was selected and coupled with ultrasound assisted extraction. Response surface methodology and artificial neural network model (ANN) model was adopted to analyze significance of extraction parameters demonstrating high prediction levels of the ß-carotene yield, experimentally confirming the maximum ß-carotene content of 151.41 µg/mL at the optimal process condition. Extracted carotenoids in the optimal NADES extract have shown high stability during the storing period of 180 days. A switchable-hydrophilicity eutectic solvent system has been introduced as a successful way to recover extracted carotenoids from the NADES solvent. It was capable of precipitating 90% of carotenoids present in the extract. The proposed procedure is simple, easily scalable and has minimal impact on operators and the environment.


Assuntos
Fracionamento Químico/métodos , Cucurbita/química , Solventes/química , beta Caroteno/isolamento & purificação
10.
Ultrason Sonochem ; 76: 105658, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34242865

RESUMO

Phenolic compounds are secondary metabolites involved in plant adaptation processes. The development of extraction procedures, quantification, and identification of this compounds in habanero pepper (Capsicum chinense) leaves can provide information about their accumulation and possible biological function. The main objective of this work was to study the effect of the UAE method and the polarity of different extraction solvents on the recovery of phenolic compounds from C. chinense leaves. Quantification of the total phenolic content (TPC), antioxidant activity (AA) by ABTS+ and DPPH radical inhibition methods, and the relation between the dielectric constant (ε) as polarity parameter of the solvents and TPC using Weibull and Gaussian distribution models was analyzed. The major phenolic compounds in C. chinense leaves extracts were identified and quantified by UPLC-PDA-ESI-MS/MS. The highest recovery of TPC (24.39 ± 2.41 mg GAE g-1 dry wt) was obtained using MeOH (50%) by UAE method. Correlations between TPC and AA of 0.89 and 0.91 were found for both radical inhibition methods (ABTS+ and DPPH). The Weibull and Gaussian models showed high regression values (0.93 to 0.95) suggesting that the highest phenolic compounds recovery is obtained using solvents with "ε" values between 35 and 52 by UAE. The major compounds were identified as N-caffeoyl putrescine, apigenin, luteolin and diosmetin derivatives. The models presented are proposed as a useful tool to predict the appropriate solvent composition for the extraction of phenolic compounds from C. chinense leaves by UAE based on the "ε" of the solvents for future metabolomic studies.


Assuntos
Antioxidantes/isolamento & purificação , Capsicum/química , Fracionamento Químico/métodos , Fenóis/isolamento & purificação , Folhas de Planta/química , Solventes/química , Ondas Ultrassônicas , Antioxidantes/química , Cromatografia Líquida de Alta Pressão , Fenóis/química , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas em Tandem
11.
Ultrason Sonochem ; 76: 105661, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34252684

RESUMO

In this work, extraction of flavonoids from peanut shells has been studied in the presence of ultrasound and the results are compared with Soxhlet and heat reflux extraction for establishing the process intensification benefits. The process optimization for understanding the effects of operating parameters, such as ethanol concentration, particle size, solvent to solid ratio, extraction temperature, ultrasonic power and ultrasonic frequency, on the extraction of flavonoids has been investigated in details. The highest extraction yield (9.263 mg/g) of flavonoids was achieved in 80 min at optimum operating parameters of particle size of 0.285 mm, solvent to solid ratio of 40 ml/g, extraction temperature of 55 °C, ultrasonic power of 120 W and ultrasonic frequency of 45 kHz with 70% ethanol as the solvent. Two kinetic models (i.e. phenomenological model and Peleg's model) have been introduced to describe the extraction kinetic of flavonoids by fitting experimental data and predict kinetic parameters. Good performance with slight loss of goodness of fit of two models was found by comparing their coefficient of determination (R2), root mean square error (RMSE) and/or mean percentage error (MPE) values. This work would provide the reduction of degradation and the economic evaluation for the extraction processes of flavonoids from peanut shells, as well as give a better explanation for the mechanism of ultrasound.


Assuntos
Arachis/química , Fracionamento Químico/métodos , Flavonoides/isolamento & purificação , Ondas Ultrassônicas , Cinética
12.
Ultrason Sonochem ; 76: 105666, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34271396

RESUMO

This study was aimed at optimizing the astaxanthin extraction efficiency from shrimp shell (green tiger, Penaeus semisulcatus). Astaxanthin was extracted using selected nonpolar/polar solvents (petroleum ether, n-hexane, ethanol, acetone) individually and in ternary mixtures of petroleum ether, acetone, and water in ratios of 15:50:35, 50:45:5, and 15:75:10 for different times (2,4 and 6 h). The results showed that solvents with higher polarity were more suitable for the extraction of astaxanthin, and increasing the extraction time from 2 to 6 h improved the extraction yield. The conditions of extraction of astaxanthin with the desirable solvent were then optimized with the ultrasonic method using the Box-Behnken design [variables included: extraction temperature (25 to 45 °C), extraction time (5 to 15 min), and ultrasound amplitude (20 to 100%)]. Optimal extraction conditions were determined as the ultrasonic amplitude of 23.6%, extraction time of 13.9 min, and extraction temperature of 26.3 °C. Under this optimum condition, the amount of astaxanthin, ferric reducing antioxidant power, and free radical scavenging capacity of the extract were obtained as 51.5%, 1705 µmol of Fe2+/g, and 73.9%, respectively. Extraction and analysis of the extract at the optimum point were used to validate the results.


Assuntos
Exoesqueleto/química , Fracionamento Químico/métodos , Penaeidae/química , Ondas Ultrassônicas , Animais , Temperatura , Fatores de Tempo , Xantofilas/isolamento & purificação
13.
Ultrason Sonochem ; 77: 105670, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34304120

RESUMO

This study aims to investigate effects of ultrasound assisted extraction on the abalone viscera protein extraction rate and iron-chelating activity of peptides. The optimal conditions for ultrasound assisted extraction by response surface methodology was at sodium hydroxide concentration 14 g/kg, ultrasonic power 428 W and extraction time 52 min. Under the optimal conditions, protein extraction rate was 64.89%, compared with alkaline extraction of 55.67%. The iron-chelating activity of peptides affected by ultrasound technology was further evaluated by iron-chelating rate, FTIR spectroscopy and LC-HRMS/MS. Alcalase was the suitable enzyme for the preparation of iron-chelating peptides from two abalone viscera proteins, showing no significant difference between their iron-chelating rate of 16.24% (ultrasound assisted extraction) and 16.60% (alkaline extraction). Iron binding sites from the two hydrolysates include amino and carboxylate terminal groups and peptide bond of the peptide backbone as well as amino, imine and carboxylate from side chain groups. Moreover, 24 iron-chelating peptides were identified from hydrolysate (alcalase, ultrasound assisted extraction), which were different from the 27 iron-chelating peptides from hydrolysate (alcalase, alkaline extraction). This study suggests the application of ultrasound technology in the generation of abalone viscera-derived iron-chelating peptides which have the ability to combat iron deficiency.


Assuntos
Fracionamento Químico/métodos , Quelantes de Ferro/isolamento & purificação , Quelantes de Ferro/farmacologia , Moluscos , Proteínas/isolamento & purificação , Proteínas/farmacologia , Ondas Ultrassônicas , Vísceras , Animais
14.
Molecules ; 26(13)2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34279379

RESUMO

Sulforaphane (SFN) is a powerful health-promoting compound found in broccoli in the form of its inactive precursor, glucoraphanin (GFN). SFN formation occurs through the enzymatic hydrolysis of glucoraphanin by myrosinase under specific chemical conditions. Its incorporation in food formulations has been hindered by the thermal instability of SFN and low concentration in Brassicaceae. Then, extracting SFN from broccoli at a temperature below 40 °C appears as an option to recover and stabilize SFN, aiming at delivering it as a nutraceutical. We studied an eco-friendly extraction process to obtain an SFN-rich extract from broccoli. The effect of the broccoli mass/solvent ratio, ethanol concentration in the extractant solution, and extraction time on the recovery of SFN, GFN, phenolic compounds, and antioxidant activity were studied through a Box-Behnken design. The regression models explained more than 70% of the variability in the responses, adequately representing the system. The experimental factors differently affected the bioactive compound recovery and antioxidant activity of the extracts. The extraction conditions that allowed the highest recovery of bioactive compounds and antioxidant activity were identified and experimentally validated. The results may provide the basis for the design of a process to produce a sulforaphane-rich food supplement or nutraceutical by using a GRAS extractant.


Assuntos
Brassica/química , Fracionamento Químico/métodos , Isotiocianatos/química , Sulfóxidos/química , Etanol/química , Glucosinolatos/análise , Glucosinolatos/química , Isotiocianatos/análise , Oximas/análise , Oximas/química , Extratos Vegetais/química , Sulfóxidos/análise
15.
Se Pu ; 39(1): 34-45, 2021 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-34227357

RESUMO

Aquatic products, which are among the most important sources of animal protein, contain proteins, vitamins, and a variety of trace elements, thus occupying an indispensable part of a reasonable diet. China is the largest consumer market of aquatic products in the world. The quality and safety of aquatic products are closely related not only to the healthy development of the aquaculture industry, but also to people's health. However, the presence of harmful substances has a bearing on the quality and safety of aquatic products in the overall process, including breeding, processing, storage, and transportation. These harmful substances are enriched in aquatic products and are transferred to humans via the food chain. Accurate determination of such harmful substances in aquatic product samples is imperative because of their complex matrices and extremely low concentrations. Many efficient sample preparation techniques such as liquid-liquid extraction, solid-phase extraction, and QuEChERS (quick, easy, cheap, effective, rugged, and safe method) with different configurations have been developed and widely employed for preconcentration in different matrices of aquatic products. Meanwhile, solid-phase microextraction has been demonstrated to be advantageous for some volatile and ultra-trace harmful substances. Suitable sample preparation techniques are important for effectively removing matrix interferences as well as for improving the sensitivity and accuracy of the method. It is important to develop appropriate sample preparation techniques for different target compounds in aquatic products. The harmful substances in aquatic products can be segregated into three categories according to their sources: (1) environmental pollutants in aquatic products; (2) substances acquired during aquaculture, transportation, and processing; (3) biotoxins in aquatic products. This article reviews the progress in sample pretreatment techniques for three harmful substances in aquatic products over the past decade. Various sample pretreatment techniques have been summarized and described, including liquid-liquid extraction, solid-phase extraction, solid-phase microextraction, QuEChERS, and magnetic solid-phase extraction. In addition, the merits and demerits of these techniques and future research directions are discussed. Finally, we reviewed the progress in functionalized materials for the preparation of aquatic product samples. With the increasing demand for aquatic products, quick, sensitive, and practical detection methods, such as surface-enhanced Raman scattering (SERS) are gaining importance. SERS has great potential for fast and accurate on-site detection of harmful substances in aquatic products. Several nondestructive sample pretreatment techniques have also been developed for harmful substances in aquatic products. The application and development of these techniques will guarantee the safety of aquatic products. Moreover, in vivo solid-phase microextraction is a potential method for aquatic product analysis. This technique integrates sampling, extraction, and enrichment into a single step, thus significantly reducing the processing time, labor, and cost. Overall, with the development and application of sophisticated materials and techniques, we can expect theoretical and practical advances in aquatic product analysis.


Assuntos
Fracionamento Químico/métodos , Poluentes Ambientais , Contaminação de Alimentos/análise , Alimentos Marinhos/análise , Animais , China , Poluentes Ambientais/análise , Humanos , Extração Líquido-Líquido , Extração em Fase Sólida , Microextração em Fase Sólida
16.
Food Chem ; 361: 129866, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34091399

RESUMO

This study investigated the in vitro bioactivities of extracts obtained from viscera, spines, shells, and gonads of Stomopneustes variolaris using subcritical water extraction (SWE) at 110 °C, 150 °C, 190 °C, and 230 °C and Soxhlet extraction. The highest amounts of phenolics (22.68 ± 0.05 mg GAE/g), flavonoids (27.11 ± 0.10 mg RE/g), and proteins (40.25 ± 0.84 mg BSA/g) were recorded from gonads at 230 °C, whereas maximum sugar content (23.38 ± 1.30 mg glucose/g) was in viscera at 150 °C. Gonads at 230 °C exhibited the highest DPPH activity (78.68 ± 0.18%), whereas viscera at 150 °C exhibited the highest ABTS+ (98.92 ± 1.27%) and protein denaturation inhibition activity (37.13 ± 9.94%). Viscera at 110 °C claimed the highest amylase inhibition (42.46 ± 0.83%), and spines at 150 °C had the highest anticancer activity (IC50 = 767.47 µg/mL). SWE achieved superior results in bioactive compound recovery and detected higher levels of bioactivities (p < 0.05). Results suggest processing sea urchin extracts via SWE has potential application to the food and pharmaceutical industries.


Assuntos
Produtos Biológicos/farmacologia , Fracionamento Químico/métodos , Ouriços-do-Mar/química , Animais , Anti-Inflamatórios não Esteroides/isolamento & purificação , Anti-Inflamatórios não Esteroides/farmacologia , Antineoplásicos/isolamento & purificação , Antineoplásicos/farmacologia , Antioxidantes/isolamento & purificação , Antioxidantes/farmacologia , Produtos Biológicos/isolamento & purificação , Avaliação Pré-Clínica de Medicamentos , Flavonoides/análise , Flavonoides/isolamento & purificação , Flavonoides/farmacologia , Química Verde , Células HeLa , Humanos , Hipoglicemiantes/isolamento & purificação , Hipoglicemiantes/farmacologia , Fenóis/análise , Fenóis/isolamento & purificação , Fenóis/farmacologia , Água/química
17.
ACS Appl Mater Interfaces ; 13(26): 31010-31020, 2021 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-34160200

RESUMO

The development of high-performance protein-imprinted materials is vital to meet the requirements of proteomics research but remains a challenge. Herein, a new type of raspberry-like cytochrome C-imprinted nanoparticle was first designed and fabricated via surface imprinting technology combined with a template immobilization strategy. In particular, the state-of-the-art metal-organic framework (MOF)/carbon nanoparticle (CN) composites were selected as protein immobilization carriers for two advantages: (1) the composites reflected the intrinsic characteristics of MOFs including flexible design, facile preparation, and extensive interactions with proteins and (2) the utilization of composites also overcame the issue associated with the severe agglomeration of individual MOFs during the post-use process. Therefore, the as-prepared composites exhibited a regular raspberry-like shape with good dispersion (polydispersity index (PDI) < 0.25), high specific surface area (551.4 m2 g-1), and outstanding cytochrome C immobilization capacity (900 mg g-1). Furthermore, a zwitterionic monomer was chosen to participate in the synthesis of an imprinting layer to reduce the nonspecific binding with proteins. As a result, the unique design presented here in both the protein immobilization carrier and the selected polymer composition endowed the imprinted material (noted as CN@UIO-66@MIPs) with the excellent ability for cytochrome C enrichment with extremely high recognition ability (imprinting factor (IF) = 6.1), rapid adsorption equilibrium time (40 min), and large adsorption capacity (815 mg g-1). Furthermore, encouraged by the experimental results, we successfully used CN@UIO-66@MIPs to specifically capture cytochrome C in mixed protein solutions and biological samples, which proved them to be a potential candidate for protein separation and purification.


Assuntos
Citocromos c/isolamento & purificação , Estruturas Metalorgânicas/química , Polímeros Molecularmente Impressos/química , Nanopartículas/química , Adsorção , Animais , Carbono/química , Fracionamento Químico/métodos , Citocromos c/química , Cinética , Compostos Organometálicos/química , Ácidos Ftálicos/química , Ratos
18.
Ultrason Sonochem ; 76: 105630, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34146974

RESUMO

Polyphenols in carobs have recently attracted great attention due to their wide range of biological and health promoting effects. A comprehensive study was conducted to find an optimum method for the extraction, purification and characterization of these valuable bioactive substances. Under this framework, the ultrasound-assisted extraction (UAE) of polyphenols from carob pulp was optimized by the maximization of the yield in total phenolics using response surface methodology. In particular, the effects of solid-solvent ratio, solvent concentration, extraction time, sonication amplitude, and sonication mode were investigated and optimized using a complete experimental design. In comparison to conventional extraction techniques, UAE offered a higher yield of antioxidants and a shorter processing time. Solid-phase extraction was evaluated as a clean-up strategy prior to the electrophoretic analysis of extracts. The results from the analysis of real samples revealed the predominance of gallic acid and highlighted the great influence of the ripening stage on carobs composition.


Assuntos
Antioxidantes/química , Antioxidantes/isolamento & purificação , Fracionamento Químico/métodos , Galactanos/química , Mananas/química , Gomas Vegetais/química , Polifenóis/análise , Ondas Ultrassônicas , Solventes/química
19.
Ultrason Sonochem ; 76: 105625, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34147916

RESUMO

Ultrasound has a significant effect on the rate of various processes in food, perfume, cosmetic, pharmaceutical, bio-fuel, materials, or fine chemical industries, despite some shortcomings. Combination with other conventional or innovative techniques can overcome these limitations, enhance energy, momentum and mass transfer, and has been successfully demonstrated in many recent studies. Various ultrasound combined hybrid and innovative techniques are systematically summarized in this review for the first time. Ultrasound can be combined with diverse conventional techniques including Soxhlet, Clevenger, enzyme, hydrotropes, ionic liquids, Deep Eutectic Solvents (DES) or Natural Deep Eutectic Solvents (NADES), to enhance mixing and micro-mixing, reduced thermal and concentration gradients, and selective extraction. Moreover, combinations of ultrasound with other innovative techniques such as microwave, extrusion, supercritical fluid, subcritical and pressure liquids, Instant controlled pressure drop (DIC), Pulsed Electric Field (PEF), Ultra-Violet (UV) or Infra-Red (IR) radiations, Counter-current chromatography (CCC), or centrifugal partition chromatographs (CPC) can enable reduced equipment size, faster response to process control, faster start-up, increased production, and elimination of process steps. The theories and applications of these ultrasound combined hybrid and innovative techniques as well as their advantages and limitations are compared, and further perspectives are proposed. This review provides new insights into advances in ultrasound combined techniques and their application at research, educational, and industrial level in modern food and plant-based chemistry.


Assuntos
Produtos Biológicos/isolamento & purificação , Fracionamento Químico/métodos , Manipulação de Alimentos/métodos , Ondas Ultrassônicas
20.
Methods Mol Biol ; 2348: 285-304, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34160815

RESUMO

During the last years, the study of extracellular vesicles (EVs) and its cargo has gained interest in the scientific media. EVs have been found in all biofluids and it is postulated that all cells are capable to secrete a wide variety of these vesicles, which play a key role in different cell-to-cell communication processes as well as in the microenvironment modulation. In the EV cargo, DNA, protein, and RNA molecules can be found, including long noncoding RNAs (lncRNAs). Several authors consider the study of EV lncRNAs an ideal source of biomarkers due to the easy sampling of EVs in different biofluids and the high specificity of the lncRNA expression pattern.In the present chapter, a detailed explanation of the EV isolation workflow followed by RNA isolation and lncRNA gene expression study is provided for two sample sources: blood plasma and cell culture conditioned media. EVs from both plasma samples and cell cultured media are isolated using sequential ultracentrifugation method (UC), which has been reported as one of the best methods available to date in terms of purity. UC is followed by RNA extraction based on the combination of phenol/guanidine-based lysis of samples with silica-membrane-based purification of total RNA. LncRNA quantification is performed by qRT-PCR. This chapter includes detailed discussion on lncRNA quantification using hydrolysis probes, recommended housekeeping genes and evaluation of methods for comparing lncRNA levels between EVs and its parental cells. In summary, we describe here the main steps for a successful isolation of the EVs-lncRNA cargo, paying attention to how overcome the different challenges found in the experimental procedure and in the data analysis of lncRNA expression from this source.


Assuntos
Ácidos Nucleicos Livres , Meios de Cultivo Condicionados/metabolismo , Vesículas Extracelulares/metabolismo , RNA Longo não Codificante/genética , Biomarcadores , Fracionamento Químico/métodos , Exossomos/metabolismo , Humanos , Biópsia Líquida/métodos , Reação em Cadeia da Polimerase , RNA Longo não Codificante/sangue , RNA Longo não Codificante/isolamento & purificação , RNA Longo não Codificante/metabolismo , Reprodutibilidade dos Testes
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