Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 1.415
Filtrar
1.
Molecules ; 29(5)2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38474659

RESUMO

Currently, in the ongoing development of the tobacco industry, a large amount of tobacco rhizomes is discarded as waste. These wastes are usually disposed of through incineration or burial. However, these tobacco wastes still have some economic value. High-purity nicotine has a promising market outlook as the primary raw material for electronic cigarette liquid. Nicotine is not only found in tobacco leaves but also in the rhizomes of tobacco plants. This study presents a method for treating tobacco waste and extracting high-purity nicotine from it. After mixing the raw material powder and entrainer in specific ratios, as much of the nicotine in tobacco roots can be extracted as possible using supercritical carbon dioxide extraction. The effects of temperature, the ratio of the entrainer, and the volume fraction of ethanol in the entrainer on the nicotine yield in supercritical fluid extraction (SFE) at 25 MPa for 120 min were discussed. By using 90% ethanol (a raw material mass-to-volume ratio of 1:5) as the entrainer, we obtained the highest nicotine yield of 0.49% at 65 °C. Meanwhile, the purity of the crude extract was 61.71%, and after purification, it increased to 97.57%. In this way, we can not only obtain nicotine with market value but also further reduce the harm to the environment caused by tobacco waste disposal.


Assuntos
Cromatografia com Fluido Supercrítico , Sistemas Eletrônicos de Liberação de Nicotina , Rizoma , Nicotina , Dióxido de Carbono , Tabaco , Etanol , Cromatografia com Fluido Supercrítico/métodos
2.
Anal Methods ; 16(15): 2278-2285, 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38525815

RESUMO

Sterols are unsaponifiable lipids resulting from plant metabolism that exhibit interesting bioactive properties. Microalgae are a major source of specific phytosterols, most of which are still not fully characterized. The similarity in sterol structures and the existence of positional isomers make the separation of phytosterols challenging. A method was developed based on an offline two-dimensional (2D) system, reversed-phase liquid chromatography (RPLC)-supercritical fluid chromatography (SFC)/quadrupole time-of-flight (Q-ToF) mass spectrometry, for the identification of sterols in microalgae. Subsequent positive-mode MS/MS was used to confirm the identified phytosterols. The 2D chromatogram exhibited a pattern related to the positions of the double bonds, which were confirmed by standard injection, enabling structural elucidation. The analysis of the unsaponifiable fraction of two algae, namely Scenedesmus obliquus, a freshwater microalgae, and Padina pavonica, a marine macroalgae, highlighted the ability of the method to distinguish a large number of sterol isomers.


Assuntos
Cromatografia com Fluido Supercrítico , Microalgas , Fitosteróis , Cromatografia de Fase Reversa/métodos , Fitosteróis/análise , Espectrometria de Massas em Tandem/métodos , Cromatografia com Fluido Supercrítico/métodos , Esteróis , Plantas
3.
J Chromatogr A ; 1720: 464811, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38490143

RESUMO

A novel silica stationary phase was designed and prepared through thiol-epoxy click chemistry for supercritical fluid chromatography (SFC). The developed stationary phase was characterized by elemental analysis, Fourier transform infrared spectrometry and solid-state 13C/CP MAS NMR spectroscopy. In order to evaluate the chromatographic performance and retention mechanisms of the prepared column, a variety of alkaloids were used, including indoles, isoquinolines, pyrrolidines, piperidines, quinolizidines and organic amines. The stationary phase showed more symmetrical peak shapes and better performance for these compounds compared to the conventional SFC stationary phases. The investigations on the effects of pressure and temperature on retention provided information that the selectivity of the compounds can be improved by changing the density of the supercritical fluids. Moreover, it shows improved separation efficiency of three natural products with alkaloids as the main components at high sample loading. In conclusion, the developed stationary phase could offer flexible selectivity toward alkaloids and complex samples.


Assuntos
Alcaloides , Cromatografia com Fluido Supercrítico , Cromatografia com Fluido Supercrítico/métodos , Compostos de Sulfidrila , Temperatura , Aminas , Dióxido de Silício/química
4.
Artigo em Inglês | MEDLINE | ID: mdl-38513431

RESUMO

Fat-soluble vitamin D is an essential bioactive compound important for human health. Insufficient vitamin D levels can result not only in bone disease but also in other disorders, such as cancer, metabolic disorders, and diseases related to poor immune function. The current methods commonly used for vitamin D analysis are often applied to determine the levels of the most abundant metabolite in plasma, i.e., 25-OH-D2/D3. These methods do not consider the presence of other hydroxylated and esterified metabolites, including isomers and epimers, which are typically found in low concentrations. In this study, we developed a fast and selective ultra-high performance supercritical fluid chromatography (UHPSFC) method using a 150 mm long 1-amino anthracene (1-AA) column and a mobile phase consisting of carbon dioxide and methanol/isopropanol (1/1, v/v) mixed with 8 % water. After thorough optimization of column temperature and back pressure, the separation of four vitamin D3 esters, vitamin D3 and D2, and eight mono- and di-hydroxylated metabolites, including three groups of isomers, was achieved in 10 min. Two ion sources, atmospheric pressure chemical ionization (APCI) and atmospheric pressure photoionization optimized within this study, were compared in tandem mass spectrometry (MS/MS) detection. No significant sensitivity differences were observed. Subsequently, the same 1-AA column chemistry was examined in ultra-high performance liquid chromatography (UHPLC) as the stationary phase that could hypothetically bring different selectivity in the separation of vitamin D and its metabolites. However, this hypothesis was rejected, and C18 was used as a stationary phase in the final optimized UHPLC-MS/MS method. Despite detailed optimization, the final 15 min UHPLC method was not able to separate di-hydroxylated isomers of vitamin D3, while it enabled better resolution of esterified forms compared to UHPSFC. Optimized methods provided similar repeatability of retention times and peak areas, with RSD < 2 % and 10 %, respectively. The lowest limits of quantification were in the range of 1.2 - 4.9 ng/mL for UHPSFC-APCI-MS/MS, while for UHPLC-APCI-MS/MS, they were typically in the range of 2.6 - 9.6 ng/mL. Based on the obtained results, the UHPSFC-APCI-MS/MS method was the most promising approach for fast, selective, and sensitive analysis that could be applied in the analysis of biological samples with emphasis on the separation of both hydroxylated and esterified metabolites, including isomeric forms.


Assuntos
Cromatografia com Fluido Supercrítico , Vitamina D , Humanos , Espectrometria de Massas em Tandem/métodos , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia com Fluido Supercrítico/métodos , Vitaminas , Colecalciferol
5.
Int J Biol Macromol ; 258(Pt 2): 129168, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38171432

RESUMO

Tyrosinase is a key enzyme in enzymatic browning, causing quality losses in food through the oxidation process. Thus, the discovery of an effective and natural tyrosinase inhibitor via green technology is of great interest to the global food market due to food security and climate change issues. In this study, Syzygium aqueum (S. aqueum) leaves, which are known to be rich in phenolic compounds (PC), were chosen as a natural source of tyrosinase inhibitor, and the effect of the sustainable, supercritical fluid extraction (SFE) process was evaluated. Response surface methodology-assisted supercritical fluid extraction (RSM-assisted SFE) was utilized to optimize the PCs extracted from S. aqueum. The highest amount of PC was obtained at the optimum conditions (55 °C, 3350 psi, and 70 min). The IC50 (661.815 µg/mL) of the optimized extract was evaluated, and its antioxidant activity (96.8 %) was determined. Gas chromatography-mass spectrometry (GC-MS) results reveal that 2',6'-dihydroxy-4'-methoxychalcone (2,6-D4MC) (82.65 %) was the major PC in S. aqueum. Chemometric analysis indicated that 2,6-D4MC has similar chemical properties to the tyrosinase inhibitor control (kaempferol). The toxicity and physiochemical properties of the novel 2,6-D4MC from S. aqueum revealed that the 2,6-D4MC is safer than kaempferol as predicted via absorption, distribution, metabolism, and excretion (ADME) evaluation. Enzyme kinetic analysis shows that the type of inhibition of the optimized extract is non-competitive inhibition with Km = 1.55 mM and Vmax = 0.017 µM/s. High-performance liquid chromatography (HPLC) analysis shows the effectiveness of S. aqueum as a tyrosinase inhibitor. The mechanistic insight of the tyrosinase inhibition using 2,6-D4MC was successfully calculated using density functional theory (DFT) and molecular docking approaches. The findings could have a significant impact on food security development by devising a sustainable and effective tyrosinase inhibitor from waste by-products that is aligned with the United Nation's SDG 2, zero hunger.


Assuntos
Cromatografia com Fluido Supercrítico , Syzygium , Monofenol Mono-Oxigenase , Syzygium/química , Quimiometria , Quempferóis , Cromatografia com Fluido Supercrítico/métodos , Simulação de Acoplamento Molecular , Cinética , Extratos Vegetais/química
6.
J Chromatogr A ; 1716: 464640, 2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38219626

RESUMO

In the last decade, the separation application based on aromatic stationary phases has been demonstrated in supercritical fluid chromatography (SFC). In this paper, four aromatic stationary phases involving aniline (S-aniline), 1-aminonaphthalene (S-1-ami-naph), 1-aminoanthracene (S-1-ami-anth) and 1-aminopyrene (S-1-ami-py) were synthesized based on full porous particles (FPP) silica, which were not end-capped for providing extra electrostatic interaction. Retention mechanism of these phases in SFC was investigated using a linear solvation energy relationship (LSER) model. The aromatic stationary phases with five positive parameters (a, b, s, e and d+) can provide hydrogen bonding, π-π, dipole-dipole and cation exchange interactions, which belong to the moderate polar phases. The LSER results obtained using routine test solutes demonstrated that the aforementioned interactions of four aromatic stationary phases were influenced by the type and bonding density of the ligand, but to a certain extent. Furthermore, the LSER data verified that the S-1-ami-anth column based on full porous particles silica had higher cation exchange capacity (d+ value), compared to the commercialized 1-AA column (based on the ethylene-bridged hybrid particles). The relationship between the d+ value and SFC additive was quantitatively proved so as to regulate electrostatic interaction reasonably. This value was greatly increased by phosphoric acid, slightly increased by trifluoroacetic acid and formic acid, but significantly reduced by ammonium formate and diethylamine. Taking the S-1-ami-naph column as an example, better peek shape of the flavonoids was obtained after the addition of 0.1 % phosphoric acid in MeOH while isoquinoline alkaloids were eluted successfully within 11 min after adding 0.1 % diethylamine in MeOH. Combined with the unique π-π interaction and controllable electrostatic interaction, the aromatic stationary phases in this study have been proven to have expandable application potential in SFC separation.


Assuntos
Cromatografia com Fluido Supercrítico , Ácidos Fosfóricos , Cromatografia com Fluido Supercrítico/métodos , Dióxido de Silício/química , Cátions , Compostos de Anilina , Dietilaminas
7.
Anal Chem ; 96(3): 1320-1327, 2024 01 23.
Artigo em Inglês | MEDLINE | ID: mdl-38193397

RESUMO

Supercritical fluid chromatography (SFC) is a rapidly expanding technique in the analysis of nonpolar to moderately polar substances and, more recently, also in the analysis of compounds with higher polarity. Herein, we demonstrate a proof of concept for the application of a commercial SFC instrument with electrospray ionization-mass spectrometry (MS) detection as a platform for the comprehensive analysis of metabolites with the full range of polarities, from nonpolar lipids up to highly polar metabolites. The developed single-platform SFC-MS lipidomic/metabolomic method is based on two consecutive injections of lipid and polar metabolite extracts from biphase methyl tert-butyl ether extraction using a diol column and two different gradient programs of methanol-water-ammonium formate modifier. Detailed development of the method focused mainly on the pressure limits of the system, the long-term repeatability of results, and the chromatographic performance, including optimization of the flow rate program, modifier composition and gradient, and injection solvent selection. The developed method enabled fast and comprehensive analysis of lipids and polar metabolites from plasma within a 24 min cycle with two injections using a simple analytical platform based on a single instrument, column, and mobile phase. Finally, the results from SFC-MS analysis of polar metabolites were compared with widely established liquid chromatography MS analysis in metabolomics. The comparison showed different separation selectivity of metabolites using both methods and overall lower sensitivity of the SFC-MS due to the higher flow rate and worse chromatographic performance.


Assuntos
Cromatografia com Fluido Supercrítico , Lipidômica , Cromatografia com Fluido Supercrítico/métodos , Metabolômica/métodos , Espectrometria de Massas por Ionização por Electrospray , Lipídeos
8.
Electrophoresis ; 45(3-4): 218-233, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37794622

RESUMO

In this work, a preparative supercritical fluid chromatography (SFC) method was first developed to separate a series of chiral compounds evaluated as lactam-based P2RX7 antagonists. Subsequently, high-performance liquid chromatography, SFC, and capillary electrophoresis (CE) were comparatively investigated as QC tools to determine the enantiomeric purity of the separated isomers, including analytical performance and greenness. The screening of the best conditions was carried out in liquid and SFC on the nine derivatives and the amylose tris(3,5-dimethylphenylcarbamate)-based chiral stationary phase was found to be highly efficient. The same screening was carried out in CE and very different conditions, either in acidic or basic background electrolyte and different cyclodextrins used as chiral selectors, allowed the separation of six of the nine derivatives. 1-((3,4-Dichlorophenyl)carbamoyl)-5-oxopyrrolidine-2-carboxylic acid (compound 1) was chosen as a probe, and its semi-preparative separation by SFC and enantiomeric verification using the three techniques are presented. Its limit of detection and limit of quantification are calculated for each method. Finally, the greenness of each quality control method was evaluated.


Assuntos
Amilose , Cromatografia com Fluido Supercrítico , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia com Fluido Supercrítico/métodos , Estereoisomerismo , Eletroforese Capilar
9.
J Chromatogr A ; 1713: 464546, 2024 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-38041976

RESUMO

Supercritical fluid chromatography (SFC), now using carbon dioxide as a major component of the mobile phase, has been known for over 60 years but still some misunderstandings remain about its capabilities. Amongst them, SFC is often described as a normal-phase chromatographic technique, based on different considerations: polarity of the stationary phase, elution order of the analytes, relative non-polarity of the mobile phase, non-linear retention behaviour, or adsorption retention mechanisms. All of these assumptions are true to a certain extent, and in certain circumstances. But also, all of these assumptions are wrong in different circumstances. In this paper, the criteria to categorize SFC as a normal-phase chromatographic method will be examined individually, considering all knowledge acquired from the early years of its development. Finally, it will appear that the "normal-phase" glass lens is greatly reducing the true extent of SFC's possibilities.


Assuntos
Cromatografia com Fluido Supercrítico , Cromatografia com Fluido Supercrítico/métodos , Dióxido de Carbono/química , Adsorção
10.
Biomed Chromatogr ; 38(3): e5759, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37845809

RESUMO

Matrix effect (ME) is commonly caused by coelution of compounds with target analytes, resulting in either suppression or enhancement of analyte ionization. Thus, to achieve the desired accuracy, precision, and sensitivity, ME needs to be evaluated and controlled during bioanalytical method development. As the application of supercritical fluid chromatography-mass spectrometry (SFC-MS) for analysis of biological samples has increased, ME using SFC-MS has also been investigated with a focus on the difference in ME in SFC-MS compared to other chromatographic techniques used for achiral separation in biological samples. Here, we provide a summary of the status of ME evaluation and mitigation in SFC-MS methods. This review presents an overview of the phenomenon of ME and methods for evaluating ME in bioanalysis. Next, the factors that can impact ME in SFC-MS-based bioanalytical methods are discussed in detail with an emphasis on SFC. A literature review of the evaluation of ME in targeted bioanalytical methods using SFC-MS is included at the end. Robust instrumentation, effective sample preparation, and superb separation selectivity are the foundations of reliable analytical methods as well as the ability to mitigate detrimental ME in SFC-MS methods.


Assuntos
Cromatografia com Fluido Supercrítico , Cromatografia com Fluido Supercrítico/métodos
11.
J Sep Sci ; 47(1): e2300655, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38014608

RESUMO

Metconazole is one of the widely-used chiral triazole fungicides in controlling wheat leaf rust, powdery mildew, Fusarium head blight with high efficacy, and so forth. In the current work, the effects of chiral stationary phases, alcoholic modifiers, and column temperature on the chiral separation of metconazole were discussed in detail. Amylose tris(3,5-dimethylphenylcarbamate)-coated chiral stationary phase exhibited much stronger chiral recognition ability toward metconazole stereoisomers in the CO2 /ethanol mixture as compared to the others. Then, a two-step semi-preparative separation of metconazole was performed through supercritical fluid chromatography and high-performance liquid chromatography, and the enantiomeric excess values of four stereoisomers were achieved over 98%. Moreover, the enantioselective cytotoxicity of cis-metconazole against HepG2 cells has been investigated, and the order of the cell proliferation toxicity against HepG2 cells was (1R, 5S)-metconazole > (1S, 5R)-metconazole > the mixture. Briefly, this study would provide valuable information in the preparative separation of optically pure metconazole products through chromatographic techniques and their environmental risk assessment.


Assuntos
Cromatografia com Fluido Supercrítico , Estereoisomerismo , Cromatografia com Fluido Supercrítico/métodos , Amilose/química , Triazóis/toxicidade
12.
J Sep Sci ; 47(1): e2300623, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38066396

RESUMO

A supercritical fluid chromatography-tandem mass spectrometry (SFC-MS/MS) technique was developed for the rapid and simultaneous detection of nine pesticides (carbendazim, isoprocarb, paclobutrazol, isoprothiolane, flusilazole, quinalphos, piperonylbutoxide, propargite, and bioresmethrin) in rice, wheat, and maize. The cereal samples were extracted with a solution of 0.5% acetic acid in acetonitrile and purified using quick, easy, cheap, effective, rugged, and safe method. The samples were characterized using multi-reaction monitoring and quantified with the external standard method. Excellent linearities (R2  > 0.9991) and limits of quantification (0.4-40.0 µg/kg) were established for all nine pesticides. Satisfactory pesticide recovery rates (62.2%-107.4%) were obtained at three standard concentrations (50, 100, and 200 µg/kg), with relative standard deviations in the range of 2.1%-14.3%. The results confirmed that the proposed method was suitable for the routine detection of these pesticides in grain samples. Compared with high-performance liquid chromatography-MS/MS, the overall test run time and the amount of solvent required were reduced by 66% and 90%, respectively, when SFC-MS/MS was applied. Therefore, the use of SFC-MS/MS permits a shorter run time and affords greater analytical efficiency, such that it is both economical and environmentally sustainable.


Assuntos
Cromatografia com Fluido Supercrítico , Resíduos de Praguicidas , Praguicidas , Espectrometria de Massas em Tandem/métodos , Resíduos de Praguicidas/análise , Grão Comestível/química , Cromatografia com Fluido Supercrítico/métodos , Praguicidas/análise , Cromatografia Líquida de Alta Pressão/métodos
13.
Food Res Int ; 175: 113769, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38129060

RESUMO

This experiment aimed to establish a green, simple and highly sensitive method (supercritical fluid chromatography (SFC) coupled with ion mobility quadrupole time-of-flight mass spectrometry (IM-Q-TOF/MS)) for the detection of multiple pesticides in foods. During the experiments, several important SFC parameters, such as stationary phase, modifier, make-up solution, back-temperature and back-pressure were optimized. Here, single-field collision cross section (CCS) values and multifield CCS values of 20 pesticides were examined by IM-Q-TOF/MS as highly specific parameters with excellent experimental precision. In addition, based on accurate mass matching and fragment ion comparison, mass fragments were obtained by IM-Q-TOF/MS, which elucidated the regularities of compound structure and characteristic fragment ions. Under the optimized conditions, satisfactory linearity (R2 ≥ 0.9989) and recoveries (79.60 % to 112.97 %) were obtained. The intra- and interday precisions were favorable, with RSDs lower than 4.91 and 7.65 %, respectively. Additionally, the method showed low limits of detection (0.1-8.8 ng/mL). The proposed method has been successfully applied to the highly sensitive detection of phenylurea herbicide, triazine herbicides, organophosphorus pesticide, pyrethroid insecticide and acaricide in yam and potato.


Assuntos
Cromatografia com Fluido Supercrítico , Resíduos de Praguicidas , Praguicidas , Resíduos de Praguicidas/análise , Praguicidas/análise , Cromatografia com Fluido Supercrítico/métodos , Compostos Organofosforados/análise , Espectrometria de Massas
14.
Anal Chim Acta ; 1285: 342010, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38057057

RESUMO

BACKGROUND: The determination of plant hormones is still a very challenging analytical discipline, mainly due to their low concentration in complex plant matrices. Therefore, the involvement of very sensitive high-throughput techniques is required. Cytokinins (CKs) are semi-polar basic plant hormones regulating plant growth and development. Modern methods for CK determination are currently based on ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS), which enables the separation of CK isomeric forms occurring endogenously in plants. Here, ultra-high performance supercritical fluid chromatography coupled with tandem mass spectrometry (UHPSFC-MS/MS) was used for the simultaneous determination of 37 CK metabolites. RESULTS: The chromatographic conditions were tested on three different columns with various retention mechanisms. Hybrid silica modified with 2-picolylamine was selected as the stationary phase. Several parameters such as column temperature, back pressure regulation, mobile phase composition and make-up solvent were investigated to achieve efficient separation of CK isomers and reasonable sensitivity. Compared to UHPLC-MS/MS, a 9-min chromatographic analysis using a mobile phase of supercritical CO2 and 5 mM ammonia in methanol represents a three-fold acceleration of total run time. The quantification limit of UHPSFC-MS/MS method was in the range of 0.03-0.19 fmol per injection and the method validation showed high accuracy and precision (below 15 % for most analytes). The method was finally applied to the complex plant matrix of the model plant Arabidopsis thaliana and the obtained profiles of CK metabolites were compared with the results from the conventional UHPLC-MS/MS method. SIGNIFICANCE: The presented work offers a novel approach for quantification of endogenous CKs in plants. Compared to the conventional UHPLC-MS/MS, the total run time is shorter and the matrix effect lower for the key CK metabolites. This approach opens the opportunity to utilize UHPSFC-MS/MS instrumentation for targeted plant hormonomics including other plant hormone families.


Assuntos
Cromatografia com Fluido Supercrítico , Espectrometria de Massas em Tandem , Humanos , Espectrometria de Massas em Tandem/métodos , Citocininas , Reguladores de Crescimento de Plantas , Cromatografia com Fluido Supercrítico/métodos , Cromatografia Líquida de Alta Pressão/métodos , Plantas
15.
Molecules ; 28(23)2023 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-38067455

RESUMO

Mosla chinensis Maxim is an annual herb with many potential purposes in agricultural, industrial, and pharmaceutical fields. At present, the extract of the whole plant from M. chinensis has been proven to demonstrate antifungal, antioxidant, and anti-inflammatory activities. Previous studies focused on the enzyme pretreatment in hydrodistillation from M. chinensis. However, organic solvent or supercritical fluid carbon dioxide extraction (SFE-CO2) methods, which are commonly utilized in industry, have seldom been studied and cannot provide multiple evaluations of yield. In this work, we analysed compounds from M. chinensis by HPLC-DAD, discussed n-hexane extraction, and conducted further investigations on SFE-CO2 through the design of response surface methodology (RSM). The sample obtained from pilot-scale SFE-CO2 was also tested against nine kinds of microorganisms. Single-factor results revealed that the extraction rates from M. chinensis by steam distillation, n-hexane extraction, and SFE-CO2 were 1%, 2.09%, and 3.26%, respectively. RSM results showed a significant improvement in extraction rate through optimising pressure and time, and the interaction of both factors was more important than that of temperature-pressure and temperature-time. A pilot-scale test with an extraction rate of 3.34% indicated that the predicted RSM condition was operable. In addition, samples from the pilot-scale SFE-CO2 showed antibacterial effects against three previously unreported bacteria (Gardnerella vaginalis, methicillin-resistant Staphylococcus aureus, and Propionibacterium acnes). These results fill the gap in previous research and provide more information for the application and development of M. chinensis in the future.


Assuntos
Cromatografia com Fluido Supercrítico , Lamiaceae , Staphylococcus aureus Resistente à Meticilina , Óleos Voláteis , Óleos Voláteis/análise , Dióxido de Carbono , Cromatografia Líquida de Alta Pressão , Cromatografia com Fluido Supercrítico/métodos
16.
Molecules ; 28(24)2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-38138602

RESUMO

Pomegranate (Punica granatum L.) is a widely used fruit in the dietary supplement industry due to its richness in bioactive compounds. In this study, an experimental design was applied to optimize supercritical fluid extraction (SFE) of polar compounds of interest (ellagic acid and punicalagins), known for antioxidant and skin care properties from pomegranate's pericarp. The effects of temperature, modifier percentage, and water additive percentage added in the modifier were explored through a Box-Behnken design, followed by a study of the extraction kinetics. The results indicated that 40 °C, 20% EtOH:H2O 80:20 v:v, with an extraction duration of 60 min allowed for the highest recovery of the above-mentioned molecules (19.59 mg/g). Due to solubilization issues encountered by the extract, a screening of cosmetic solvents was carried out to solubilize SFE pomegranate extracts and a composition of Gly:H2O 80:20 v:v was selected. Furthermore, an integrated SFE pre-formulation process of pomegranate pericarp extract (PPE) was elaborated. This allowed for the recovery of the extracts in cosmetic solvent, avoiding a full evaporation. Finally, the stability of the pre-formulated extracts was evaluated and showed high stability for over 3 months at 5 °C.


Assuntos
Cromatografia com Fluido Supercrítico , Punica granatum , Extratos Vegetais/farmacologia , Cromatografia com Fluido Supercrítico/métodos , Antioxidantes , Solventes
17.
Molecules ; 28(20)2023 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-37894538

RESUMO

One of the many advantages of supercritical fluid extraction (SFE) is the possibility of using it in sequential and selective approaches. This is due to the use of a dynamic extraction mode in addition to the possibility of altering the composition of the modifier during the extraction process. In this study, the optimization of Calendula officinalis L. extraction of non-polar and polar compounds was achieved using three-level Box-Behnken designs (BBD). For non-polar compounds, the factors were pressure, temperature, and EtOH percentage. As for the polar compounds, the three variables were temperature, the total modifier percentage, and H2O added in the modifier as an additive. The recovery of selectively rich extracts in triterpendiol esters and narcissin was possible using a sequential two-step SFE. The first step was performed at 80 °C and 15% EtOH, and the second at 40 °C and 30% EtOH:H2O 80:20 v:v with a total of 60 min of extraction. Additionally, the SFE extraction of non-polar compounds was scaled up on a pilot-scale extractor, demonstrating similar results. Finally, the SFE results were compared to ultrasound-assisted extraction (UAE).


Assuntos
Calendula , Cromatografia com Fluido Supercrítico , Triterpenos , Flavonoides , Extratos Vegetais , Cromatografia com Fluido Supercrítico/métodos , Flores , Etanol
18.
Se Pu ; 41(10): 866-878, 2023 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-37875409

RESUMO

Supercritical fluid chromatography (SFC) is an environment-friendly and efficient column chromatography technology that was developed to expand the application range of high performance liquid chromatography (HPLC) using a supercritical fluid as the mobile phase. A supercritical fluid has a temperature and pressure that are above the critical values as well as relatively dynamic characteristics that are between those of a gas and liquid. Supercritical fluids combine the advantages of high solubility and diffusion, as their diffusion and viscosity coefficients are equivalent to those of a gas, while maintaining a density that is comparable with that of a liquid. Owing to the remarkable compressibility of supercritical fluids, analyte retention in SFC is significantly influenced by the density of the mobile phase. Thus, the column temperature and back pressure are crucial variables that regulate analyte retention in SFC. Increasing the back pressure can increase the density and solubility of the mobile phase, leading to reductions in retention time. The column temperature can affect selectivity and retention, and the degree to which different analytes are affected by this property varies. On the one hand, increasing the temperature reduces the density of the mobile phase, thereby extending the retention time of the analytes; on the other hand, it can also increase the energy of molecules, leading to a shorter retention time of the analyte on the stationary phase. CO2, the most widely employed supercritical fluid to date, presents moderate critical conditions and, more importantly, is miscible with a variety of polar organic solvents, including small quantities of water. In comparison with the mobile phases used in normal-phase liquid chromatography (NPLC) and reversed-phase liquid chromatography (RPLC), the mobile phase for SFC has a polarity that can be extended over a wide range on account of its extensive miscibility. The compatibility of the mobile phase determines the diversity of the stationary phase. Nearly all stationary phases for HPLC, including the nonpolar stationary phases commonly used for RPLC and the polar stationary phases commonly used for NPLC, can be applied to SFC. Because all stationary phases can use the same mobile-phase composition, chromatographic columns with completely different polarities can be employed in SFC. The selectivity of SFC has been effectively expanded, and the technique can be used for the separation of diverse analytes ranging from lipid compounds to polar compounds such as flavonoids, saponins, and peptides. The choice of stationary phase has a great impact on the separation effect of analytes in SFC. As new stationary phases for HPLC are constantly investigated, specialized stationary phases for SFC have also been continuously developed. Researchers have discovered that polar stationary phases containing nitrogen heterocycles such as 2-EP and PIC are highly suitable for SFC because they can effectively manage the peak shape of alkaline compounds and provide good selectivity in separating acidic and neutral compounds.The development of various stationary phases has promoted the applications of SFC in numerous fields such as pharmaceuticals, food production, environmental protection, and natural products. In particular, natural products have specific active skeletons, multiple active groups, and excellent biological activity; hence, these materials can provide many new opportunities for the discovery of novel drugs. According to reports, compounds related to natural products account for 80% of all commercial drugs. However, natural products are among the most challenging compounds to separate because of their complex composition and low concentration of active ingredients. Thus, superior chromatographic methods are required to enable the qualitative and quantitative analysis of natural products. Thanks to technological improvements and a good theoretical framework, the benefits of SFC are gradually becoming more apparent, and its use in separating natural products is expanding. Indeed, in the past 50 years, SFC has developed into a widely used and efficient separation technology. This article provides a brief overview of the characteristics, advantages, and development process of SFC; reviews the available SFC stationary phases and their applications in natural products over the last decade; and discusses prospects on the future development of SFC.


Assuntos
Cromatografia com Fluido Supercrítico , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Cromatografia com Fluido Supercrítico/métodos , Solventes/química , Água
19.
Molecules ; 28(19)2023 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-37836716

RESUMO

Supercritical fluid extraction (SFE) is an innovative green technology for the extraction of phytochemicals from plants. Therefore, this study aimed to evaluate the application of SFE and to optimize the extraction conditions of the Thai herbal formula, Kleeb Bua Daeng (KBD). A Box-Behnken design (BBD) with response surface methodology (RMS) was used to determine the effect of the extraction time (30-90 min), temperature (30-60 °C), and pressure (200-300 bar) on response variables including the extraction yield, total phenolic content (TPC), total flavonoid content (TFC), total carotenoid content (TCC), and total anthocyanin content (TAC) of the KBD formula. The highest percentage extraction yield (3.81%) was achieved at 60 °C, 300 bar, and 60 min of the extraction time. The highest TPC (464.56 mg gallic acid equivalents/g extract), TFC (217.19 mg quercetin equivalents/g extract), and TCC (22.26 mg ß-carotene equivalents/g extract) were all achieved at 60 °C, 250 bar, and 90 min of the extraction time. On the contrary, it was not possible to quantify the total anthocyanin content as anthocyanins were not extracted by this method. The results indicated that SFE-CO2 is a suitable method of extraction for a green recovery of phytochemicals with low and moderate polarity from the KBD formula.


Assuntos
Dióxido de Carbono , Cromatografia com Fluido Supercrítico , Dióxido de Carbono/química , Antocianinas , Carotenoides , Fenóis/análise , Extratos Vegetais/química , Cromatografia com Fluido Supercrítico/métodos
20.
Anal Chim Acta ; 1279: 341831, 2023 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-37827647

RESUMO

BACKGROUND: Developing an environmentally friendly and efficient integrated analytical approach is a cutting-edge topic in current analytical science. Due to the unique properties of supercritical carbon dioxide (sc-CO2), online supercritical fluid extraction-supercritical fluid chromatography (SFE-SFC) is developing rapidly and has been widely applied in many fields. However, it still faces several challenges such as peak broadening and matrix interference. In order to solve the problems, we developed an inline phase transition trapping-selective supercritical fluid extraction-supercritical fluid chromatography (PTT-SSFE-SFC)-tandem mass spectrometry (MS/MS) method in this study. RESULTS: This method integrated extraction, purification, separation, and detection, which was applied to determine 114 prohibited substances in cosmetics within 33 min, covering ten categories. The PTT strategy trapped the extracts on the head of the column by transforming CO2 from a supercritical state to a gaseous state, preventing peak spreading and improving sensitivity. Several adsorbents were tested when analyzing aqueous samples to reduce matrix interference and absorb water. Compared with conventional online SFE-SFC, this method improved the matrix effects of 93 and 87 target substances in the toner and mask matrix, respectively. Because the integrated method reduced sample loss, it achieved high sensitivity with LODs ranging from 0.00104 µg L-1 to 3.09 µg L-1. Furthermore, compared with other reported green methods, the inline method showed advantages in automation, efficiency, sample amount, and waste volume. SIGNIFICANCE AND NOVELTY: With the introduction of the PTT strategy and the adsorbent, the system obtained good peak shapes, high sensitivity, low matrix effect, and good recovery. Based on the results, inline PTT-SSFE-SFC-MS/MS as a green and efficient integrated method has great potential for analyzing low abundance and multiple categories of targets in complex samples.


Assuntos
Cromatografia com Fluido Supercrítico , Espectrometria de Massas em Tandem , Espectrometria de Massas em Tandem/métodos , Cromatografia com Fluido Supercrítico/métodos , Dióxido de Carbono , Limite de Detecção , Água
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...