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1.
Sensors (Basel) ; 21(11)2021 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-34200436

RESUMO

Measurement of pH in aqueous-organic mixtures with different compositions is of high importance in science and technology, but it is, at the same time, challenging both from a conceptual and practical standpoint. A big part of the difficulty comes from the fundamental incomparability of conventional pH values between solvents (spH, solvent-specific scales). The recent introduction of the unified pH (pHabs) concept opens up the possibility of measuring pH, expressed as pHabsH2O, in a way that is comparable between solvent, and, thereby, removing the conceptual problem. However, practical issues remain. This work presents the experience of the authors with measuring pHabsH2O values in mixtures of methanol, ethanol, and acetonitrile, with water, but without the presence of buffers or other additives. The aim was to assigned pHabsH2O values to solvent-water mixtures using differential potentiometry and the 'pHabs-ladder' method. Measurements were made of the potential difference between glass electrodes immersed in different solutions, separated by an ionic liquid salt bridge. Data were acquired for a series of solutions of varying solvent content. This work includes experiences related to: a selection of commercial electrodes, purity of starting material, and comparability between laboratories. Ranges of pHabsH2O values for selected compositions of solvent-water mixtures are presented.


Assuntos
Metanol , Água , Acetonitrilas , Etanol , Concentração de Íons de Hidrogênio , Solventes
2.
Talanta ; 233: 122523, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34215026

RESUMO

Deep eutectic solvents (DESs) have been considered to be one of the most promising green alternatives of conventional volatile solvents for liquid-liquid separation. However, acidic hydrophobic DESs have been less studied although they are of great importance for the extraction of compounds which are unstable in alkaline conditions. In this study, a novel family of acidic hydrophobic deep eutectic solvents was designed and prepared from methyl trioctyl ammonium chloride and a series of haloacetic acids. For the first time, the obtained DESs were used for extraction and determination of calcium dobesilate, which is an extensively used medicine for treating vascular diseases, but it can be easily oxidized under alkaline and neutral conditions. The factors influencing extraction process including pH, temperature, extract time, inorganic salts and organic coexistence were systematically investigated. It is found that these DESs exhibited outstanding extraction performance towards calcium dobesilate. The extraction equilibrium time was only 3 min in a wide range of pH (1.2-9.2) at room temperature and the extraction capacity was up to 504 mg/g. The detection limit of calcium dobesilate extracting from water samples was 0.05 µg/L and the limit of quantification was 0.5 µg/L. A variety of inorganic salts with the concentration up to 1.0 mol/L and common coexisting organic compounds, such as glucose and starch, with the concentration more than 1000 times higher than the target analyte had no obvious impact on the extraction efficiency. The relative recovery for real samples ranged from 93.2% to 108.6%. Furthermore, the DESs could be recycled and regenerated through back extraction. After fifteen cycles, the extraction efficiency was still up to 99%. Finally, the extraction and back extraction mechanism was discussed in detail.


Assuntos
Dobesilato de Cálcio , Poluentes Químicos da Água , Interações Hidrofóbicas e Hidrofílicas , Solventes , Água , Poluentes Químicos da Água/análise
3.
Molecules ; 26(13)2021 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-34206357

RESUMO

In the current work, a simple, economical, accurate, and precise HPLC method with UV detection was developed to quantify Favipiravir (FVIR) in spiked human plasma using acyclovir (ACVR) as an internal standard in the COVID-19 pandemic time. Both FVIR and ACVR were well separated and resolved on the C18 column using the mobile phase blend of methanol:acetonitrile:20 mM phosphate buffer (pH 3.1) in an isocratic mode flow rate of 1 mL/min with a proportion of 30:10:60 %, v/v/v. The detector wavelength was set at 242 nm. Maximum recovery of FVIR and ACVR from plasma was obtained with dichloromethane (DCM) as extracting solvent. The calibration curve was found to be linear in the range of 3.1-60.0 µg/mL with regression coefficient (r2) = 0.9976. However, with acceptable r2, the calibration data's heteroscedasticity was observed, which was further reduced using weighted linear regression with weighting factor 1/x. Finally, the method was validated concerning sensitivity, accuracy (Inter and Intraday's % RE and RSD were 0.28, 0.65 and 1.00, 0.12 respectively), precision, recovery (89.99%, 89.09%, and 90.81% for LQC, MQC, and HQC, respectively), stability (% RSD for 30-day were 3.04 and 1.71 for LQC and HQC, respectively at -20 °C), and carry-over US-FDA guidance for Bioanalytical Method Validation for researchers in the COVID-19 pandemic crisis. Furthermore, there was no significant difference for selectivity when evaluated at LLOQ concentration of 3 µg/mL of FVIR and relative to the blank.


Assuntos
Amidas/análise , Amidas/sangue , Antivirais/análise , Antivirais/sangue , Bioensaio/métodos , COVID-19/tratamento farmacológico , Cromatografia Líquida de Alta Pressão/métodos , Extração Líquido-Líquido/métodos , Pirazinas/análise , Pirazinas/sangue , Aciclovir/análise , Aciclovir/sangue , COVID-19/sangue , Calibragem , Estabilidade de Medicamentos , Congelamento , Humanos , Padrões de Referência , Reprodutibilidade dos Testes , Solventes/química
4.
Molecules ; 26(13)2021 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-34208968

RESUMO

Two common extraction solvent systems, namely acidified aqueous methanol and acidified aqueous acetone, were used to extract blackberry phenolics, and the antioxidant properties of the recovered extracts were compared. The crude extracts were fractionated into low- and high-molecular-weight phenolics by Sephadex LH-20 column chromatography. The hydrophilic-oxygen radical absorbance capacity (H-ORACFL), ferric reducing antioxidant power (FRAP), and the cellular antioxidant activity (CAA) assays were employed as indices to assess antioxidant capacity of the extracts and their respective fractions. The methanolic solvent system displayed a greater efficiency at extracting anthocyanin and flavonol constituents from the blackberries, while the acetonic solvent system was better at extracting flavan-3-ols and tannins. Anthocyanins were the dominant phenolic class found in the blackberries with 138.7 ± 9.8 mg C3G eq./100 g f.w. when using methanol as the extractant and 114.6 ± 3.4 mg C3G eq./100 g f.w. when using acetone. In terms of overall antioxidant capacity of blackberry phenolics, the acetonic solvent system was superior. Though present only as a small percentage of the total phenolics in each crude extract, the flavan-3-ols (42.37 ± 2.44 and 51.44 ± 3.15 mg/100 g f.w. in MLF and ALF, respectively) and ellagitannins (5.15 ± 0.78 and 9.31 ± 0.63 mg/100 g f.w. in MHF and AHF, respectively) appear to account for the differences in the observed antioxidant activity between the two solvent systems.


Assuntos
Acetona/química , Antocianinas , Antioxidantes , Metanol/química , Extratos Vegetais/química , Rubus/química , Antocianinas/química , Antocianinas/isolamento & purificação , Antioxidantes/química , Antioxidantes/isolamento & purificação , Fenóis/química , Fenóis/isolamento & purificação , Solventes/química , Estados Unidos
5.
Molecules ; 26(13)2021 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-34209151

RESUMO

Subcritical water refers to high-temperature and high-pressure water. A unique and useful characteristic of subcritical water is that its polarity can be dramatically decreased with increasing temperature. Therefore, subcritical water can behave similar to methanol or ethanol. This makes subcritical water a green extraction fluid used for a variety of organic species. This review focuses on the subcritical water extraction (SBWE) of natural products. The extracted materials include medicinal and seasoning herbs, vegetables, fruits, food by-products, algae, shrubs, tea leaves, grains, and seeds. A wide range of natural products such as alkaloids, carbohydrates, essential oil, flavonoids, glycosides, lignans, organic acids, polyphenolics, quinones, steroids, and terpenes have been extracted using subcritical water. Various SBWE systems and their advantages and drawbacks have also been discussed in this review. In addition, we have reviewed co-solvents including ethanol, methanol, salts, and ionic liquids used to assist SBWE. Other extraction techniques such as microwave and sonication combined with SBWE are also covered in this review. It is very clear that temperature has the most significant effect on SBWE efficiency, and thus, it can be optimized. The optimal temperature ranges from 130 to 240 °C for extracting the natural products mentioned above. This review can help readers learn more about the SBWE technology, especially for readers with an interest in the field of green extraction of natural products. The major advantage of SBWE of natural products is that water is nontoxic, and therefore, it is more suitable for the extraction of herbs, vegetables, and fruits. Another advantage is that no liquid waste disposal is required after SBWE. Compared with organic solvents, subcritical water not only has advantages in ecology, economy, and safety, but also its density, ion product, and dielectric constant can be adjusted by temperature. These tunable properties allow subcritical water to carry out class selective extractions such as extracting polar compounds at lower temperatures and less polar ingredients at higher temperatures. SBWE can mimic the traditional herbal decoction for preparing herbal medication and with higher extraction efficiency. Since SBWE employs high-temperature and high-pressure, great caution is needed for safe operation. Another challenge for application of SBWE is potential organic degradation under high temperature conditions. We highly recommend conducting analyte stability checks when carrying out SBWE. For analytes with poor SBWE efficiency, a small number of organic modifiers such as ethanol, surfactants, or ionic liquids may be added.


Assuntos
Produtos Biológicos , Temperatura Alta , Extratos Vegetais/química , Sonicação , Água/química , Produtos Biológicos/química , Produtos Biológicos/isolamento & purificação , Solventes/química
6.
Anal Chim Acta ; 1174: 338743, 2021 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-34247738

RESUMO

Quick and visual detection of component contents, such as water, in a mixed solvent is important for many practical applications, and a full range detection is especially preferred. In this work, a carbon dots based ratiometric fluorescent sensor was synthesized by grafting fluorescent group (Rhodamine B, RhB) on carbon dots, and the dual emission peaks exhibited a linear ratiometric response with the change of polarity and hydrogen bond of Solvent Hansen solubility parameters. This responsive behavior is attributed to surface state photoluminescence mechanisms, and has been used for the quantitative detection of water content in ethanol with an excellent linear relationship (R2 = 0.996), a low detection limit (0.2%), and a full detection range (0-100%). Furthermore, a paper-based ratiometric fluorescence sensing strip is also demonstrated, which exhibits good storage stability and sensitivity. This study suggests that RhB grafted carbon dots could be feasibly and effectively used as ratiometric fluorescent sensors for solvent content detection.


Assuntos
Carbono , Pontos Quânticos , Corantes Fluorescentes , Rodaminas , Solventes
7.
Molecules ; 26(12)2021 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-34205529

RESUMO

Polyscias fruticosa (L.) leaves contain significant bioactive compounds with high antioxidant activity such as chlorophylls, total polyphenols, etc. but these have still been underutilized. In this study, the kinetics of chlorophyll and antioxidant activity extraction from P. fruticosa leaves by microwave-assisted extraction (MAE) were investigated. Microwave power was 300, 450, or 600 (W); the ratio of material/solvent varied from 1:40 to 1:80 (g/mL). In this study, the second-order kinetic model successfully predicted the change of chlorophyll and antioxidant activity during MAE. The increase of microwave power or/and the solvent amount increased saturated extraction efficiency and the extraction rate constant. However, the saturated concentration of chlorophyll and antioxidant activity increased with the increment of microwave power and the decrease in solvent amount.


Assuntos
Antioxidantes/farmacologia , Araliaceae/química , Clorofila/farmacologia , Extratos Vegetais/farmacologia , Folhas de Planta/química , Cromatografia Líquida de Alta Pressão/métodos , Etanol/química , Cinética , Micro-Ondas , Extratos Vegetais/química , Polifenóis/química , Polifenóis/farmacologia , Solventes/química
8.
Se Pu ; 39(3): 324-330, 2021 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-34227313

RESUMO

Organic solvents can be used to dissolve and disperse flavors, bactericides, preservatives, surfactants, oils, and coloring agents during the production of cosmetics. However, harmful chlorinated hydrocarbon organic solvents are found in cosmetics such as manicure products, anti-acne products, and perfumes. Long-term contact with such cosmetics will have an adverse effect on the consumers' health. Past research has focused on very few chlorinated hydrocarbon organic solvents in cosmetics. Most organic solvents with low boiling points are typically determined by headspace-gas chromatography-mass spectrometry. In this study, a high-boiling-point solvent was used as the injection solvent, and the solvent delay time was cancelled. The compounds that could only peak during the solvent delay time were effectively separated. A method coupling sample pretreatment with gas chromatography-mass spectrometry (GC-MS) was developed for the simultaneous determination of 18 chlorinated hydrocarbon organic solvents in cosmetics: vinylidene chloride, dichloromethane, trans-1,2-dichloroethylene, 1,1-dichloroethane, cis-1,2-dichloroethylene, chloroform, 1,1,1-trichloroethane, carbon tetrachloride, 1,2-dichloroethane, trichloroethylene, 1,1,2-trichloroethane, tetrachloroethylene, 1,1,1,2-tetrachloroethane, 1,1,2,2-tetrachloroethane, 1,2,3-trichloropropane, pentachloroethane, hexachloroethane, and hexachloro-1,3-butadiene. These 18 solvents have a wide range of polarities and a notable difference in volatilities, in addition to many isomers and structural analogs, which renders their separation difficult. Therefore, the separation effect of three kinds of GC columns with different polarities was compared. n-Tetradecane, an injection solvent with good solubility, was selected as the extraction solvent. An organic solvent with high polarity has low extraction rate because of its weak polarity. Adding sodium chloride solution to the sample to induce the "salting out" effect could change the partition coefficient of the components, thereby improving the extraction rate. Therefore, the concentration of the sodium chloride solution added to the sample was optimized. In this work, liquid-liquid extraction was the main extraction process, so the effects of different shaking times, temperatures, and frequencies on the extraction rate were discussed. The optimized results are as follows: at normal temperature, the sample dispersed or dissolved in saturated sodium chloride solution was extracted by n-tetradecane at an oscillating speed of 100 r/min for 20 min. Separation was performed on an Agilent J&W DB-624 column (30 m×0.25 mm×1.4 µm) by GC-MS with an electrospray ionization (EI) source in the selected ion monitoring (SIM) mode. The external standard method was used for quantitative determination. The 18 compounds could be analyzed within 19 min. The linear equations, linear correlation coefficients, and linear ranges were obtained by analyzing a series of mixed standard working solutions. The limits of detection (LODs, S/N=3) and limits of quantification (LOQs, S/N=10) of the 18 components were determined. The negative lipstick (solid) and mouthwash (liquid) samples were used as the spiked sample matrix at three levels, and the recoveries and precisions were calculated. The calibration curves showed good linearities for the 18 chlorinated hydrocarbon organic solvents in range of 0.2-100 mg/L, with correlation coefficients (R2) not less than 0.9992. The LODs and LOQs were in the range of 0.033-0.049 mg/L and 0.10-0.15 mg/L, respectively. The average recoveries of the 18 chlorinated hydrocarbon organic solvents in lipstick (solid) and mouthwash (liquid) were 92.4%-103.1% and 93.3%-102.4% respectively; the corresponding relative standard deviations (RSDs) were 3.1%-5.3% and 2.8%-5.4% (n=6). This method was used to determine 115 different types of cosmetics, and tetrachloroethylene was detected in three nail polishes. With its advantages of high sensitivity, good precision, and accuracy, the developed method is suitable for the quantitative analysis of the aforesaid 18 compounds in all kinds of cosmetics. The study findings would serve as a reference for the quality and safety monitoring of cosmetics.


Assuntos
Cosméticos , Hidrocarbonetos Clorados , Solventes/análise , Cosméticos/análise , Cromatografia Gasosa-Espectrometria de Massas , Hidrocarbonetos Clorados/análise , Conservantes Farmacêuticos
9.
Se Pu ; 39(4): 415-423, 2021 Apr 08.
Artigo em Chinês | MEDLINE | ID: mdl-34227762

RESUMO

A fast and simple ultra-high-performance liquid chromatography using diode array detector (UHPLC-DAD) technique has been developed for the simultaneous determination of 22 sunscreen agents (UV filters), viz. phenylbenzimidazole sulfonic acid (PBS), terephthalydene dicamphor sulfonic acid (TDS), benzophenone-4 (BZ4), camphor benzalkonium methosulfate (CBM), benzophenone-2 (BZ2), benzylidene camphor sulfonic acid (BCS), benzophenone-3 (BZ3), 3-benzylidene camphor (3BC), isoamyl p-methoxycinnamate (IMC), 4-methylbenzylidene camphor (MBC), diethylamino hydroxybenzoyl hexyl benzoate (DHHB), octocrylene (OCR), butyl methoxydibenzoyl methane (BDM), ethylhexyl dimethyl PABA (EDP), ethylhexyl methoxycinnamate (EMC), homosalate (HS), ethylhexyl salicylate (ES), diethylhexyl butamido triazone (DBT), ethylhexyl triazone (ET), drometrizole trisiloxane (DRT), methylene bis-benzotriazolyl tetramethylbutylphenol (MBP), and bis-ethylhexyloxyphenol methoxyphenyl triazine (EMT) in cosmetic products. Different parameters, such as column type, oven temperature, mobile phase composition, and detection wavelength, were studied. The best chromatographic separation was obtained under the following conditions: Poroshell 120 EC-C18 (100 mm×4.6 mm, 2.7 µm) column set at 25 ℃ and gradient acetonitrile-isopropanol-water (containing 50 mmol/L ammonium acetate and 0.05% (v/v) formic acid) as the mobile phase, pumped at a flow rate of 0.5 mL/min, with a wavelength of 311 nm. The proposed UHPLC-DAD technique provided separation of the 22 target sunscreen agents within 35 min, with the optimized sample pretreatment procedure below. First, samples were mixed thoroughly by adding 2 mL or 5 mL tetrahydrofuran, followed by vortex and dispersal. If the wax samples were still not homogenized completely, an ultrasonic dispersal protocol with heating to 50 ℃ was adopted. Second, the homogeneous samples were ultrasonically extracted with ethanol containing 0.1% (v/v) formic acid. The developed method showed good linear relationships, with correlation coefficients of no less than 0.998. Two kinds of samples with different matrix types were fortified at three levels. The average spiked recoveries of 22 UV filters ranged from 85.2% to 112.3%, with the relative standard deviations (RSDs) ranging from 0.5% to 6.5%. The limits of detection were between 0.7 and 64 mg/kg, and the limits of quantification ranged from 2.4 mg/kg to 215 mg/kg. Moreover, the stabilities of the mixed standard solutions at the levels of 2, 10, and 50 mg/L were tested. The stability results showed that drometrizole trisiloxane was stable for 12 h, while the others were stable for 36 h. The reliability of the developed method was demonstrated by applying it to 16 commercial sunscreen-containing cosmetic samples obtained from the Chinese market. The levels determined in this study agreed well with those of five commercial samples (such as emulsion and cream). The method developed was remarkably different from the standard method, which is mentioned in the Safety and Technical Standards for Cosmetics (2015 edition), especially in terms of mobile phase composition and extraction solvent. Compared to the standard method, this method bypassed the use of large amounts of corrosive solvents like tetrahydrofuran and perchloric acid, thus improving the extraction efficiency of low-polarity components like drometrizole trisiloxane, methylene bis-benzotriazolyl tetramethylbutylphenol, and bis-ethylhexyloxyphenol methoxyphenyl triazine, and the analytes were well separated with better stability. Benzophenone-2 was added to this method as another detection component. The good analytical features, as well as their environment-friendly characteristics, make the presented method suitable not only for routine analysis in cosmetics industries, but also as a candidate reference method for sunscreen analysis.


Assuntos
Cosméticos , Protetores Solares , Cromatografia Líquida de Alta Pressão , Cosméticos/análise , Reprodutibilidade dos Testes , Solventes , Protetores Solares/análise
10.
Int J Mol Sci ; 22(13)2021 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-34199144

RESUMO

Cyanine fluorescent dyes are attractive diagnostic or therapeutic agents due to their excellent optical properties. However, in free form, their use in biological applications is limited due to the short circulation time, instability, and toxicity. Therefore, their encapsulation into nano-carriers might help overcome the above-mentioned issues. In addition to indocyanine green (ICG), which is clinically approved and therefore the most widely used fluorescent dye, we tested the structurally similar and cheaper alternative called IR-820. Both dyes were encapsulated into liposomes. However, due to the synthetic origin of liposomes, they can induce an immunogenic response. To address this challenge, we proposed to use erythrocyte membrane vesicles (EMVs) as "new era" nano-carriers for cyanine dyes. The optical properties of both dyes were investigated in different biological relevant media. Then, the temperature stability and photo-stability of dyes in free form and encapsulated into liposomes and EMVs were evaluated. Nano-carriers efficiently protected dyes from thermal degradation, as well as from photo-induced degradation. Finally, a hemotoxicity study revealed that EMVs seem less hemotoxic dye carriers than clinically approved liposomes. Herein, we showed that EMVs exhibit great potential as nano-carriers for dyes with improved stability and hemocompatibility without losing excellent optical properties.


Assuntos
Carbocianinas , Corantes Fluorescentes , Terapia Fototérmica , Carbocianinas/administração & dosagem , Carbocianinas/química , Portadores de Fármacos/química , Membrana Eritrocítica/metabolismo , Eritrócitos/metabolismo , Vesículas Extracelulares/metabolismo , Corantes Fluorescentes/administração & dosagem , Corantes Fluorescentes/química , Verde de Indocianina/análogos & derivados , Lipossomos/síntese química , Estrutura Molecular , Terapia Fototérmica/métodos , Solubilidade , Solventes , Análise Espectral , Temperatura
11.
Int J Mol Sci ; 22(12)2021 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-34200696

RESUMO

Passiflora edulis by-products (PFBP) are a rich source of polyphenols, of which piceatannol has gained special attention recently. However, there are few studies involving environmentally safe methods for obtaining extracts rich in piceatannol. This work aimed to concentrate piceatannol from defatted PFBP (d-PFBP) by means of pressurized liquid extraction (PLE) and conventional extraction, using the bio-based solvents selected with the Hansen solubility parameters approach. The relative energy distance (Ra) between solvent and solute was: Benzyl Alcohol (BnOH) < Ethyl Acetate (EtOAc) < Ethanol (EtOH) < EtOH:H2O. Nonetheless, EtOH presented the best selectivity for piceatannol. Multi-cycle PLE at 110 °C was able to concentrate piceatannol 2.4 times more than conventional extraction. PLE exhibited a dependence on kinetic parameters and temperature, which could be associated with hydrogen bonding forces and the dielectric constant of the solvents. The acetylcholinesterase (AChE) and lipoxygenase (LOX) IC50 were 29.420 µg/mL and 27.682 µg/mL, respectively. The results reinforce the demand for processes to concentrate natural extracts from food by-products.


Assuntos
Acetilcolinesterase/química , Inibidores da Colinesterase/farmacologia , Inibidores de Lipoxigenase/farmacologia , Lipoxigenase/química , Passiflora/química , Extratos Vegetais/farmacologia , Frutas/química , Doenças Neurodegenerativas/tratamento farmacológico , Doenças Neurodegenerativas/enzimologia , Sementes/química , Solventes/química
12.
Sensors (Basel) ; 21(13)2021 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-34206344

RESUMO

Deep Eutectic Solvents (DESs) are a new class of solvents characterized by a remarkable decrease in melting point compared to those of the starting components. The eutectic mixtures can be simply prepared by mixing a Hydrogen Bond Acceptor (HBA) with a Hydrogen Bond Donor (HBD) at a temperature of about 80 °C. They have found applications in different research fields; for instance, they have been employed in organic synthesis, electrochemistry, and bio-catalysis, showing improved biodegradability and lower toxicity compared to other solvents. Herein, we review the use of DESs in biosensor development. We consider the emerging interest in different fields of this green class of solvents and the possibility of their use for the improvement of biosensor performance. We point out some promising examples of approaches for the assembly of biosensors exploiting their compelling characteristics. Furthermore, the extensive ability of DESs to solubilize a wide range of molecules provides the possibility to set up new devices, even for analytes that are usually insoluble and difficult to quantify.


Assuntos
Técnicas Biossensoriais , Catálise , Eletroquímica , Ligação de Hidrogênio , Solventes
13.
Molecules ; 26(13)2021 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-34202440

RESUMO

Usually, wine-making by-products are discarded, presenting a significant environmental impact. However, they can be used as a source of bioactive compounds. Moreover, consumers' increasing demand for naturally nutritious and healthy products requires new formulations and food product improvement, together with sustainable, environmentally friendly extraction methods. Thus, this work aimed to compare ohmic heating (OH) with conventional methodology (CONV), using food-grade solvents, mainly water, compared to standard methanol extraction of anthocyanins. No significant differences were found between the CONV and OH for total phenolic compounds, which were 2.84 ± 0.037 and 3.28 ± 0.46 mg/g DW gallic acid equivalent, respectively. The same tendency was found for antioxidant capacity, where CONV and OH presented values of 2.02 ± 0.007 g/100 g and 2.34 ± 0.066 g/100 g ascorbic acid equivalent, respectively. The major anthocyanins identified were malvidin-3-O-acetylglucoside, delphinidin-3-O-glucoside, petunidine-3-O-glucoside, cyanidin-3-O-glucoside, and peonidine-3-O-glucoside. These extracts displayed antimicrobial potential against microorganisms such as Yersinia enterocolitica, Pseudomonas aeruginosa, Salmonella enteritidis, methicillin-sensitive Staphylococcus aureus, a methicillin-resistant Staph. aureus (MRSA), and Bacillus cereus. In conclusion, OH provides similar recovery yields with reduced treatment times, less energy consumption, and no need for organic solvents (green extraction routes). Thus, OH combined with water and citric acid allows a safe anthocyanin extraction from grape by-products, thus avoiding the use of toxic solvents such as methanol, and with high biological potential, including antimicrobial and antioxidant activity.


Assuntos
Antocianinas , Anti-Infecciosos , Antioxidantes , Bactérias/crescimento & desenvolvimento , Temperatura Alta , Vitis/química , Antocianinas/química , Antocianinas/isolamento & purificação , Antocianinas/farmacologia , Anti-Infecciosos/química , Anti-Infecciosos/isolamento & purificação , Anti-Infecciosos/farmacologia , Antioxidantes/química , Antioxidantes/isolamento & purificação , Antioxidantes/farmacologia , Solventes/química , Água/química
14.
Molecules ; 26(12)2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-34203624

RESUMO

Millettia pulchra is traditionally used for treating diseases, including joint pain, fever, anemia, and allergies. It is also a potential resource of natural flavonoid derivatives, which represents major constituents of this plant. This study aimed to isolate the major compounds from M. pulchra radix, develop and validate the HPLC-PDA method to determine their contents, and optimize its extraction. Four major flavonoid derivatives (karanjin, lanceolatin B, 2",2"-dimethylpyrano-[5″,6″:7,8]-flavone, and pongamol) were isolated using silica gel column chromatography, crystallization techniques in large amounts with high purities (>95%). A simple, accurate high-performance liquid chromatography-photodiode array (HPLC-PDA) detection method has been developed and validated with significantly statistical impacts according to International Conference on Harmonization (ICH) guidelines. The Response Surface Methodology (RSM), Artificial Neural Network (ANN) models were employed to predictive performance and optimization of the extraction process. The optimized conditions for the extraction of major flavonoids were: extraction time (twice), solvent/material ratio (9.5), and ethanol concentration (72.5%). Our research suggests an effective method, which will be helpful for quality control in the pharmaceutical development of this species.


Assuntos
Flavonoides/química , Flavonoides/isolamento & purificação , Millettia/química , Antioxidantes/química , China , Cromatografia Líquida de Alta Pressão/métodos , Etanol/química , Millettia/metabolismo , Extratos Vegetais/química , Raízes de Plantas/química , Solventes/química
15.
Molecules ; 26(12)2021 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-34204264

RESUMO

The present research investigated the chemical characterization and insecticidal activity of n-Hexane extracts of Epaltes divaricata (NH-EDx) along with their chief derivatives n-Hexadecanoic acid (n-HDa) and n-Octadecanoic acid (n-ODa) against the dengue vector Aedes aegypti and lepidopteran pest Spodoptera litura. Chemical screening of NH-EDx through GC-MS analysis delivered nine major derivatives, and the maximum peak area percentage was observed in n-Hexadecanoic acid (14.63%) followed by n-Octadecadienoic acid (6.73%). The larvicidal activity of NH-EDx (1000 ppm), n-HDa (5 ppm), and n-ODa (5 ppm) against the A. aegypti and S. litura larvae showed significant mortality rate in a dose-dependent way across all the instars. The larvicidal activity was profound in the A. aegypti as compared to the S. litura across all the larval instars. The sublethal dosages of NH-EDx (500 ppm), n-HDa (2.5 ppm), and n-ODa (2.5 ppm) also showed alterations in the larval/pupal durations and adult longevity in both the insect pests. The enzyme activity revealed that the α- and ß-carboxylesterase levels were decreased significantly in both the insect pests, whereas the levels of GST and CYP450 uplifted in a dose-dependent manner of NH-EDx, n-HDa, and n-ODa. Correspondingly, midgut tissues such as the epithelial layer (EL), gut lumen (GL), peritrophic matrix (Pm), and brush border membrane (BBM) were significantly altered in their morphology across both A. aegypti and S. litura against the NH-EDx and their bioactive metabolites. NH-EDx and their bioactive metabolites n-HDa and n-ODa showed significant larvicidal, growth retardant, enzyme inhibition, and midgut toxicity effects against two crucial agriculturally and medically challenging insect pest of ecological importance.


Assuntos
Aedes/efeitos dos fármacos , Asteraceae/metabolismo , Extratos Vegetais/farmacologia , Spodoptera/efeitos dos fármacos , Animais , Asteraceae/efeitos dos fármacos , Culex/efeitos dos fármacos , Dengue/prevenção & controle , Hexanos/química , Inseticidas/farmacologia , Larva/efeitos dos fármacos , Mosquitos Vetores/efeitos dos fármacos , Folhas de Planta/química , Solventes/química
16.
Molecules ; 26(12)2021 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-34204423

RESUMO

The exploration of nonhazardous nanoparticles to fabricate a template-driven superhydrophobic surface is of great ecological importance for oil/water separation in practice. In this work, nano-hydroxyapatite (nano-HAp) with good biocompatibility was easily developed from discarded oyster shells and well incorporated with polydimethylsiloxane (PDMS) to create a superhydrophobic surface on a polyurethane (PU) sponge using a facile solution-immersion method. The obtained nano-HAp coated PU (nano-HAp/PU) sponge exhibited both excellent oil/water selectivity with water contact angles of over 150° and higher absorption capacity for various organic solvents and oils than the original PU sponge, which can be assigned to the nano-HAp coating surface with rough microstructures. Moreover, the superhydrophobic nano-HAp/PU sponge was found to be mechanically stable with no obvious decrease of oil recovery capacity from water in 10 cycles. This work presented that the oyster shell could be a promising alternative to superhydrophobic coatings, which was not only beneficial to oil-containing wastewater treatment, but also favorable for sustainable aquaculture.


Assuntos
Exoesqueleto/química , Durapatita/química , Recuperação e Remediação Ambiental/métodos , Exoesqueleto/metabolismo , Animais , Carbonato de Cálcio/química , Dimetilpolisiloxanos/química , Durapatita/isolamento & purificação , Interações Hidrofóbicas e Hidrofílicas , Nanopartículas/química , Óleos/química , Ostreidae/metabolismo , Poluição por Petróleo/análise , Poluição por Petróleo/prevenção & controle , Solventes , Propriedades de Superfície , Água/química , Purificação da Água/métodos
17.
Molecules ; 26(12)2021 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-34204457

RESUMO

Mitragyna speciosa Korth (kratom) is known for its psychoactive and analgesic properties. Mitragynine is the primary constituent present in kratom leaves. This study highlights the utilisation of the green accelerated solvent extraction technique to produce a better, non-toxic and antinociceptive active botanical extract of kratom. ASE M. speciosa extract had a dry yield (0.53-2.91 g) and showed a constant mitragynine content (6.53-7.19%) when extracted with organic solvents of different polarities. It only requires a shorter extraction time (5 min) and a reduced amount of solvents (less than 100 mL). A substantial amount of total phenolic (407.83 ± 2.50 GAE mg/g and flavonoids (194.00 ± 5.00 QE mg/g) were found in ASE kratom ethanol extract. The MTT test indicated that the ASE kratom ethanolic leaf extract is non-cytotoxic towards HEK-293 and HeLa Chang liver cells. In mice, ASE kratom ethanolic extract (200 mg/kg) demonstrated a better antinociceptive effect compared to methanol and ethyl acetate leaf extracts. The presence of bioactive indole alkaloids and flavonols such as mitragynine, paynantheine, quercetin, and rutin in ASE kratom ethanolic leaf extract was detected using UHPLC-ESI-QTOF-MS/MS analysis supports its antinociceptive properties. ASE ethanolic leaf extract offers a better, safe, and cost-effective choice of test botanical extract for further preclinical studies.


Assuntos
Mitragyna/química , Extratos Vegetais/química , Alcaloides de Triptamina e Secologanina/isolamento & purificação , Animais , Células HEK293 , Células HeLa , Humanos , Masculino , Camundongos , Mitragyna/metabolismo , Extratos Vegetais/isolamento & purificação , Folhas de Planta/química , Alcaloides de Triptamina e Secologanina/química , Solventes/química
18.
Molecules ; 26(12)2021 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-34208536

RESUMO

A ChCl: Gly (DESs) promoted environmentally benign method was developed for the first time using the reaction of aryl aldehydes and dimedone to give excellent yields of xanthene analogues. The major application of this present protocol is the use of green solvent, a wide range of substrate, short reaction times, ease of recovery, the recyclability of the catalyst, high reaction yield, and ChCl: Gly as an alternative catalyst and solvent. In addition to this, all the synthesized compounds were evaluated for their in vitro antimycobacterial activity against M. tuberculosis H37Ra (MTB) and M. bovis BCG strains. The compounds 3d, 3e, 3f, and 3j showed significant antitubercular activity against MTB and M. bovis strains with minimum inhibitory concentration (MIC) values of 2.5-15.10 µg/mL and 0.26-14.92 µg/mL, respectively. The compounds 3e, 3f, and 3j were found to be nontoxic against MCF-7, A549, HCT 116, and THP-1 cell lines. All the prepared compounds were confirmed by 1H NMR and 13C NMR analysis.


Assuntos
Cicloexanonas/química , Solventes/química , Xantenos/síntese química , Aldeídos/química , Antituberculosos/farmacologia , Linhagem Celular Tumoral , Glicerol/química , Humanos , Testes de Sensibilidade Microbiana , Simulação de Acoplamento Molecular , Mycobacterium tuberculosis/efeitos dos fármacos , Relação Estrutura-Atividade , Xantenos/química , Xantenos/isolamento & purificação
19.
Molecules ; 26(12)2021 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-34208757

RESUMO

BACKGROUND: Pesticide residues are a threat to the health of the global population, not only to farmers, applicators, and other pesticide professionals. Humans are exposed through various routes such as food, skin, and inhalation. This study summarizes the different methods to assess and/or estimate human exposure to pesticide residues of the global population. METHODS: A systematic search was carried out on Scopus and web of science databases of studies on human exposure to pesticide residues since 2019. RESULTS: The methods to estimate human health risk can be categorized as direct (determining the exposure through specific biomarkers in human matrices) or indirect (determining the levels in the environment and food and estimating the occurrence). The role that analytical techniques play was analyzed. In both cases, the application of generic solvent extraction and solid-phase extraction (SPE) clean-up, followed by liquid or gas chromatography coupled to mass spectrometry, is decisive. Advances within the analytical techniques have played an unquestionable role. CONCLUSIONS: All these studies have contributed to an important advance in the knowledge of analytical techniques for the detection of pesticide levels and the subsequent assessment of nonoccupational human exposure.


Assuntos
Exposição Ambiental/análise , Resíduos de Praguicidas/efeitos adversos , Praguicidas/efeitos adversos , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Indicadores Básicos de Saúde , Humanos , Espectrometria de Massas/métodos , Resíduos de Praguicidas/análise , Praguicidas/análise , Extração em Fase Sólida/métodos , Solventes/química
20.
Spectrochim Acta A Mol Biomol Spectrosc ; 262: 120152, 2021 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-34256238

RESUMO

Amines are widely used in many fields including agriculture, dyes, medicine and food processing. However, volatile amine vapors could initiate acute and serious damage to human bodies. Thus, highly efficient detection of volatile amine vapors has great importance for academic research as well as practical application. In this work, a turn-on type fluorescent sensor BZCO has been developed, which could be used to detect volatile amine vapors. The portable BZCO sensor can be easily prepared through immersing filter paper into its CH2Cl2 solution and then evaporating it to dryness. This paper-based amine vapor sensor exhibits high sensitivity with a relatively low detection limit at 3.82 ppm. It also has good selectivity for discriminating amine vapors from volatile organic solvents. The detection mechanism has been confirmed by UV-vis spectral analysis. The practical applications of this paper-based BZCO sensor, such as detection of food spoilage and fluorescent security ink, have been investigated. This work has developed a new fluorescent sensor BZCO, which has broad applications in various fields, including amine gas detection, security and anti-counterfeiting materials.


Assuntos
Aminas , Corantes Fluorescentes , Cumarínicos , Gases , Humanos , Solventes
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