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1.
J Chromatogr A ; 1727: 464994, 2024 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-38759461

RESUMO

This research aimed to support police forces in their battle against illicit drug trafficking by means of a multi-technique approach, based on gas chromatography. In detail, this study was focused on the profiling of volatile substances in narcotic Cannabis sativa L. flowering tops. For this purpose, the Scientific Investigation Department, RIS Carabinieri of Messina, provided 25 seized samples of Cannabis sativa L. The content of Δ9-tetrahydrocannabinol (THC), useful to classify cannabis plant as hemp (≤ 0.2 %) or as marijuana (> 0.2 %), was investigated. Essential oils of illicit drug samples were extracted using a microwave-assisted hydro-distillation (MAHD) system; GC-MS and GC-FID analytical techniques were used for the characterization of the terpenes and terpenoids fingerprint. Furthermore, the enantiomeric and carbon isotopic ratios of selected chiral compounds were investigated using a heart-cutting multidimensional GC (MDGC) approach. The latter exploited a combination of an apolar column in the first dimension, and a chiral cyclodextrin-based column in the second one, prior to parallel isotope-ratio mass spectrometry (C-IRMS) and MS detection. Finally, all the data were gathered into a statistical model, to demonstrate the existence of useful parameters to be used for the classification of seized samples.

2.
J Sep Sci ; 47(9-10): e2400155, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38772742

RESUMO

Rapid evaporative ionization mass spectrometry (REIMS) is a relatively recent MS technique explored in many application fields, demonstrating high versatility in the detection of a wide range of chemicals, from small molecules (phenols, amino acids, di- and tripeptides, organic acids, and sugars) to larger biomolecules, that is, phospholipids and triacylglycerols. Different sampling devices were used depending on the analyzed matrix (liquid or solid), resulting in distinct performances in terms of automation, reproducibility, and sensitivity. The absence of laborious and time-consuming sample preparation procedures and chromatographic separations was highlighted as a major advantage compared to chromatographic methods. REIMS was successfully used to achieve a comprehensive sample profiling according to a metabolomics untargeted analysis. Moreover, when a multitude of samples were available, the combination with chemometrics allowed rapid sample differentiation and the identification of discriminant features. The present review aims to provide a survey of literature reports based on the use of such analytical technology, highlighting its mode of operation in different application areas, ranging from clinical research, mostly focused on cancer diagnosis for the accurate identification of tumor margins, to the agri-food sector aiming at the safeguard of food quality and security.


Assuntos
Espectrometria de Massas , Espectrometria de Massas/métodos , Humanos , Metabolômica , Análise de Alimentos/métodos
3.
Anal Chim Acta ; 1304: 342555, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38637039

RESUMO

BACKGROUND: Omics is used as an analytical tool to investigate wine authenticity issues. Aging authentication ensures that the wine has undergone the necessary maturation and developed its desired organoleptic characteristics. Considering that aged wines constitute valuable commodities, the development of advanced omics techniques that guarantee aging authenticity and prevent fraud is essential. RESULTS: Α solid phase microextraction Arrow method combined with comprehensive two-dimensional gas chromatography-mass spectrometry was developed to identify volatiles in red wines and investigate how aging affects their volatile fingerprint. The method was optimized by examining the critical parameters that affect the solid phase microextraction Arrow extraction (stirring rate, extraction time) process. Under optimized conditions, extraction took place within 45 min under stirring at 1000 rpm. In all, 24 monovarietal red wine samples belonging to the Xinomavro variety from Naoussa (Imathia regional unit of Macedonia, Greece) produced during four different vintage years (1998, 2005, 2008 and 2015) were analyzed. Overall, 237 volatile compounds were tentatively identified and were treated with chemometric tools. Four major groups, one for each vintage year were revealed using the Hierarchical Clustering Analysis. The first two Principal Components of Principal Component Analysis explained 86.1% of the total variance, showing appropriate grouping of the wine samples produced in the same crop year. A two-way orthogonal partial least square - discriminant analysis model was developed and successfully classified all the samples to the proper class according to the vintage age, establishing 17 volatile markers as the most important features responsible for the classification, with an explained total variance of 88.5%. The developed prediction model was validated and the analyzed samples were classified with 100% accuracy according to the vintage age, based on their volatile fingerprint. SIGNIFICANCE: The developed methodology in combination with chemometric techniques allows to trace back and confirm the vintage year, and is proposed as a novel authenticity tool which opens completely new and hitherto unexplored possibilities for wine authenticity testing and confirmation.


Assuntos
Compostos Orgânicos Voláteis , Vinho , Vinho/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Microextração em Fase Sólida/métodos , Quimiometria , Análise por Conglomerados , Compostos Orgânicos Voláteis/análise
4.
Talanta ; 275: 126137, 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38677163

RESUMO

The present research is focused on the proposal of use of flow-modulation comprehensive two-dimensional enantio-gas chromatography (FM eGC × GC) as a valid, flexible, and possibly superior alternative to heart-cutting multidimensional enantio-GC (eMDGC). The latter, a technique of demonstrated utility, is used specifically for the targeted separation of chiral compounds, whereas FM eGC × GC can produce both targeted and high-resolution untargeted information in a single run. It is clearly possible to use eMDGC for untargeted analysis, often with a flame ionization detector (stand-by analysis), to monitor a first-dimension (1D) separation, of much lower peak capacity compared to FM eGC × GC. If eMDGC is used with mass spectrometry (MS), it is normally exploited to monitor the second-dimension (2D) separation. The analytical instrument consisted of automated solid-phase microextraction (SPME), and a low duty-cycle FM eGC × GC system (with time-of-flight MS), equipped with an enantioselective 1D column (2,3-di-O-methyl-6-t-butyl silyl ß-cyclodextrin derivative) and a 2D polyethylene glycol one. Ten Marsala wines were subjected to analysis, for the determination of chiral lactones (many at the low ppb level, due to the high concentration capacity of SPME) and for general analyte profiling. In many instances, highly complex chromatograms were attained, with statistical analysis (ANOVA-simultaneous component analysis and partial least squares discriminant analysis) used for sample differentiation.

5.
Fitoterapia ; 175: 105923, 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38554886

RESUMO

Cervical cancer is a type of cancer which affects the cervix cells. The conventional treatments for cervical cancer including surgery, chemotherapy, and radiotherapy are only effective in premature stages and less effective in late stages of this tumor. Therefore, the therapeutic strategies based on biologically active substances from plants are needed to develop for the treatment of cervical cancer. The aim of the present study was to assess in vivo toxicity, hematological and biochemical blood parameters in Wistar rats fed Retama sphaerocarpa aqueous leaf extract (RS-AE), as well as to perform in silico molecular docking studies and dynamic simulation of phenolic compounds against HPV16 oncoprotein E6 in order to identify potential inhibitors. RS-AE was found not to induce acute or sub-acute oral toxicity or significant alterations in hematological and biochemical blood parameters in Wistar rats. A total of 11 phenolic compounds were identified in RS-AE, including dihydrodaidzein glucuronide, chrysoperiol pentoside, genistin and vitexin, which turned out to have the highest binding affinity to HPV16 oncoprotein E6. Based on these results, these RS-AE phenolic compounds could be used as natural drugs against the HPV16 E6 oncoprotein.

6.
Chem Biodivers ; 21(5): e202400272, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38489001

RESUMO

Within a study focused on Sinapis pubescens subsp. pubescens wild from Sicily (Italy), an edible species still unexplored, our earlier published work has demonstrated good in vitro antioxidant properties for the flower and leaf hydroalcoholic extracts, exhibiting quite different qualitative-quantitative phenolic profiles. Herein, further research was designed to elucidate the role played by phenolic compounds in the different antioxidant mechanisms highlighted for the extracts. To achieve this goal, the crude extracts were subjected to liquid-liquid partitioning with solvents of increasing polarity; then, the fractions were investigated for their antioxidant properties using different in vitro assays. For both flowers and leaves, the ethyl acetate fractions exhibited the best activity in DPPH and reducing power assays, followed by n-butanol. The total phenolic content determination indicated these fractions as the phenolic-rich ones, which were characterized by HPLC-PDA/ESI-MS analysis. Conversely, the phenolic-rich fractions did not show any chelating activity, which was highlighted for the more hydrophobic ones.


Assuntos
Antioxidantes , Compostos de Bifenilo , Flores , Fenóis , Extratos Vegetais , Folhas de Planta , Folhas de Planta/química , Fenóis/química , Fenóis/isolamento & purificação , Fenóis/farmacologia , Flores/química , Antioxidantes/farmacologia , Antioxidantes/química , Antioxidantes/isolamento & purificação , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Extratos Vegetais/isolamento & purificação , Compostos de Bifenilo/antagonistas & inibidores , Brassicaceae/química , Picratos/antagonistas & inibidores , Cromatografia Líquida de Alta Pressão
7.
Artigo em Inglês | MEDLINE | ID: mdl-38387342

RESUMO

A rapid and practicable analytical method for the measurement of short-chain fatty acids (SCFAs) in human plasma was developed. The extraction procedure involved the use of acidified water and methyl tert-butyl ether (MTBE), while the separation and detection of SCFAs, including acetic, propionic, and butyric acids was carried out by using gas chromatography-mass spectrometry (GC-MS) technique. The novelty of the research involves reducing the analysis time (less than 7 min) by using the novel fast GC-MS method. A narrow-bore GC capillary column of dimensions 30 m × 0.25 mm ID × 0.25 µm df with acid-modified poly(ethylene glycol) stationary phase was employed for the chromatographic separation. The signals of target compounds were acquired in selected ion monitoring (SIM) mode monitoring a quantifier ion (Q) and two qualifier ions (q1 and q2). Linearity of the method, limits of detection (LoD) and quantification (LoQ) were evaluated. In detail, regression coefficients of the calibration curves were between 0.9960 and 0.9933; LoDs ranged from 0.02 µM to 0.03 µM, while LoQs from 0.06 µM to 0.10 µM.


Assuntos
Ácidos Graxos Voláteis , Éteres Metílicos , Humanos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Ácidos Graxos Voláteis/análise , Limite de Detecção , Butiratos/análise , Éteres Metílicos/análise , Ácidos Graxos
8.
Food Chem ; 443: 138610, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38301562

RESUMO

Given their multifaceted roles, carotenoids have garnered significant scientific interest, resulting in a comprehensive and intricate body of literature that occasionally presents conflicting findings concerning the proper characterization, quantification, and bioavailability of these compounds. Nevertheless, it is undeniable that the pursuit of novel carotenoids remains a crucial endeavor, as their diverse properties, functionalities and potential health benefits make them invaluable natural resources in agri-food and health promotion through the diet. In this framework, particular attention is given to ketocarotenoids, viz., astaxanthin (one of them) stands out for its possible multifunctional role as an antioxidant, anticancer, and antimicrobial agent. It has been widely explored in the market and utilized in different applications such as nutraceuticals, food additives, among others. Adonirubin and adonixanthin can be naturally found in plants and microorganisms. Due to the increasing significance of natural-based products and the remarkable opportunity to introduce these ketocarotenoids to the market, this review aims to provide an expert overview of the pros and cons associated with adonirubin and adonixanthin.


Assuntos
Cantaxantina/análogos & derivados , Carotenoides , Antioxidantes
9.
Anal Bioanal Chem ; 416(3): 801-808, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37505233

RESUMO

The present manuscript reports and discusses critical issues related to the determination of mineral oil hydrocarbon contamination in Citrus essential oils (EOs); an on-line liquid-gas chromatography system equipped with a Y-interface was used (with no additional off-line step for pre-concentration). In total, eighteen samples were analyzed, specifically eleven cold-pressed (CP) and seven distilled EOs. With regard to the CP EOs, various degrees of mineral oil saturated hydrocarbon (MOSH) contamination were detected, ranging between 10.7 and 338.4 mg kg-1 (only one sample was MOSH-free); different MOSH sub-fractions were determined, with the > C25- ≤ C35 sub-fraction always present, with an average concentration of 74.5 mg kg-1. Based on the EO composition, different sample amounts were injected to avoid the overloading of the LC column and consequently the GC one, thus leading to different limits of quantification (LoQ), which were either 2 mg kg-1 (for bergamot EO) or 5 mg kg-1 (for all the other investigated samples). For all samples, the mineral oil aromatic hydrocarbon level was always lower than the LoQ.

10.
J Chromatogr A ; 1710: 464432, 2023 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-37832462

RESUMO

The method herein described involves a rapid and limited-volume (0.5 mL of acetonitrile) solvent-extraction sample preparation process, for pesticide determination in hemp seed oil. The extraction method was characterized by the absence of both clean-up or pre-concentration steps. The extracts were directly analyzed through cryogenic-modulation comprehensive two-dimensional gas chromatography coupled to triple quadrupole mass spectrometry. The novelty characterizing the present research [compared to a previous one (Arena et al., 2023)] is related to the extension of the number of pesticides (97), and to the investigation of a more challenging matrix, contained in a vegetable oil of increasing interest among consumers. Linearity, limits of detection and quantification, accuracy, precision, recovery, and matrix effect were measured. Particular emphasis was devoted to the matrix effect, with the co-extracted matrix amount defined. Three international regulations (Canada, California, Europe) were considered, and the obtained limits of quantification were found to be too high in five (Canada) and twelve (Europe) cases, for a total number of 15 pesticides. The analysis of ten commercial samples showed the presence of seven pesticide residues in four of them, at concentration levels ranging from 0.02 to 0.98 mg kg-1, with most over the regulation residue limits.


Assuntos
Resíduos de Praguicidas , Praguicidas , Praguicidas/análise , Espectrometria de Massas em Tandem/métodos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Resíduos de Praguicidas/análise , Acetonitrilas/química
11.
J Chromatogr A ; 1710: 464409, 2023 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-37757528

RESUMO

The present research aimed to retrieve key information about the genuineness of Sicilian lemon essential oils by evaluating simultaneously the chiral and isotopic data of target terpene components. With respect to previous literature references, where chiral recognition and isotope discrimination were performed by distinct gas chromatographic methods, this study aimed to develop a single analytical approach. To overcome limitations associated to monodimensional gas chromatographic approaches, an enantio­selective multidimensional gas chromatographic approach coupled to isotopic ratio mass spectrometry and to parallel single quadrupole detection (Es-MDGC-C-IRMS/qMS) was developed. Thanks to the features of this system, enantiomeric excesses and target δ13C of the chiral and achiral components were evaluated in a single gas chromatographic run, allowing to reduce total time analysis, as well the consumption of electricity, solvents and samples. Moreover, due to the capability to baseline separate the enantiomeric couples, further considerations were done about the specific δ13C value of the target separated enantiomers. Dealing with the genuine lemon oils analysed, a different δ13C value was found between the enantiomers of the same chiral component, namely (-) and (+) of α and ß-pinene, suggesting a different isotopic fractionation related to a specific biosynthetic pathway. This research aimed to evaluate the reasons behind this behaviour, paving the way to newer considerations in the field of authenticity assessment.

12.
J Sep Sci ; 46(18): e2300529, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37590324

RESUMO

The goal of this study was to develop a method for the determination of nine phthalic acid esters in extra virgin olive oils using low-pressure gas chromatography-triple-quadrupole mass spectrometry. Sample preparation was simple, environmental friendly, and rapid inasmuch that it involved only dilution (< 1 mL of hexane). The low-pressure gas chromatography analyses were performed by using a 5 m wide-bore column. The limit of quantification for the phthalates ranged from 0.06 to 1.14 mg kg-1 . Both intra- and interday precisions were measured, with coefficient of variation values ranging from 0.2% to 11.7%. The trueness of the method was measured by evaluating accuracy at the initial stage of the work and after 2 months, with values ranging between -8.7% and 12.1%. Moreover, blind accuracy was comprised between -11.6% and 14.2%. The method involves the use of simplified instrumentation and reduced analysis times (nearly two times faster) compared to a previously published comprehensive two-dimensional gas chromatography-triple-quadrupole mass spectrometry method, leading to a reduction of energy and helium consumption. The approaches were compared in analytical terms and for the environmental impact. In total, 23 olive oil samples were analyzed, with at least one phthalate detected in all but one sample.


Assuntos
Ácidos Ftálicos , Espectrometria de Massas em Tandem , Azeite de Oliva/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Espectrometria de Massas em Tandem/métodos , Ácidos Ftálicos/análise , Óleos de Plantas/química
13.
Anal Chem ; 95(31): 11761-11768, 2023 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-37490591

RESUMO

Here, we show the potential and applicability of the novel GC-combustion-MS approach as a nitrogen-selective GC detector. Operating requirements to achieve reproducible and compound-independent formation of volatile NO species as a selective N-signal during the combustion step are described. Specifically, high temperatures (≥1000 °C) and post-column O2 flows (0.4 mL min-1 of 0.3% O2 in He) turned out to be necessary when using a vertical oven without makeup flow (prototype #1). In contrast, the use of a horizontal oven with 1.7 mL min-1 He as an additional makeup flow (prototype #2) required milder conditions (850 °C and 0.2 mL min-1). A detection limit of 0.02 pg of N injected was achieved, which is by far the lowest ever reported for any GC detector. Equimolarity, linearity, and peak shape were also adequate. Validation of the approach was performed by the analysis of a certified reference material obtaining accurate (2% error) and precise (2% RSD) results. Robustness was tested with the analysis of two complex samples with different matrices (diesel and biomass pyrolysis oil) and N concentration levels. Total N determined after the integration of the whole chromatograms (524 ± 22 and 11,140 ± 330 µg N g-1, respectively) was in good agreement with the reference values (497 ± 10 and 11,000 ± 1200 µg N g-1, respectively). In contrast, GC-NCD results were lower for the diesel sample (394 ± 42 µg N g-1). Quantitative values for the individual and families of N species identified in the real samples by parallel GC-MS and additional GC × GC-MS analyses were also obtained using a single generic internal standard.

14.
Artigo em Inglês | MEDLINE | ID: mdl-37451138

RESUMO

The proposed research was focused on the development of a gas chromatography-tandem mass spectrometry (GC-QqQ-MS) method under milder electron ionization (EI) conditions for the assay of vitamin D metabolites in human serum. Efficiency of three different silylation agents was evaluated for the conversion of vitamin D species into trimethylsilyl (TMS) derivatives, among which N-methyl-N-(trimethylsilyl)-trifluoroacetamide (MSTFA) proved to be the most effective. Indeed, the MSTFA reagent was able to convert in TMS ether even the 25-hydroxyl vitamin D derivative that, as known, possesses steric hindrance problems. The separation of vitamin D compounds was obtained in about 11.5 min using a narrow-bore column of dimensions 30 m × 0.25 mm ID × 0.10 µm df with a poly(5% diphenyl/95% dimethyl siloxane) stationary phase. The mass spectrometry ionization of the silylated derivatives was performed under milder EI conditions (20-eV energy) that, respect to common 70-eV energy, generated scan mass spectra with higher relative and absolute intensities of high-mass diagnostic ions, along with a reduced abundance of the low-mass. The signals of the ionized compounds were acquired in multi-reaction-monitoring (MRM) mode, thus enabling the obtainment of highly-sensitive and selective quantitative data. The developed method was validated in term of linearity, accuracy, limits of detection (LoD) and quantification (LoQ). In detail, regression coefficients of the calibration curves were between 0.9959 and 0.9999; LoDs ranged from 0.06 ng mL-1 to 0.73 ng mL-1 and LoQs from 0.16 ng mL-1 to 2.45 ng mL-1. With respect to accuracy, the serum SRM 972a certified reference material (Vitamin D metabolites in frozen human serum) (Levels 1-4) was analyzed.


Assuntos
Elétrons , Espectrometria de Massas em Tandem , Humanos , Espectrometria de Massas em Tandem/métodos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Vitamina D
15.
J Chromatogr A ; 1701: 464064, 2023 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-37201430

RESUMO

Due to the growing trend of organic food, there is still concern over the use of chemicals and pesticides in agriculture. In recent years, several procedures have been validated for the control of pesticides in food. In the present research, a comprehensive two-dimensional liquid chromatography coupled with tandem mass spectrometry is proposed for the first time for a multi-class analysis of 112 pesticides in corn-based products. Notably, a "reduced" QuEChERS-based method as extraction and clean-up procedure prior to the analysis, was successfully employed. Limits of quantification values were lower than the ones fixed by the European legislation; intra-day and inter-day precision were lower than 12.9% and 15.1%, respectively (at the 500 µg/kg concentration levels). Over 70% of the analytes provided recoveries between 70% and 120% range (at 50, 500 and 1000 µg/kg concentration levels) with standard deviation values below 20%. In addition, matrix effect values were in the range between 13% to 161%. The method was applied to the analysis of real samples, and three pesticides were detected at trace levels in both samples. The findings of this work pave the way for the treatment of complex matrices such as corn products.


Assuntos
Resíduos de Praguicidas , Praguicidas , Praguicidas/análise , Espectrometria de Massas em Tandem/métodos , Zea mays , Cromatografia Líquida/métodos , Agricultura , Resíduos de Praguicidas/análise
16.
Food Chem ; 424: 136423, 2023 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-37247598

RESUMO

In this work, different sol-gel sorbent-coated second-generation fabric phase sorptive extraction (FPSE) membranes were synthesized using titania-based sol-gel precursors. The proposed membranes were tested for their efficiency to extract eleven selected organophosphorus pesticides (OPPs) from apple juice samples. Among the examined materials, sol-gel C18 coated titania-based FPSE membranes showed the highest extraction efficiency. These membranes were used for the optimization and validation of an FPSE method prior to analysis by gas chromatography-mass spectrometry. The detection limits for OPPs ranged between 0.03 and 0.08 ng mL-1. Moreover, the relative standard deviation was < 8.2% and 8.4% for intra-day and inter-day studies, respectively. The relative recoveries were 91-110% (intra-day study) and 90-106% (inter-day study) for all the target analytes, demonstrating good overall method accuracy. Moreover, the novel membranes were reusable at least 5 times. The titania-based membranes were compared to the conventional silica-based membranes and their utilization resulted in higher extraction recoveries.


Assuntos
Malus , Praguicidas , Cromatografia Gasosa-Espectrometria de Massas/métodos , Praguicidas/análise , Compostos Organofosforados/análise
17.
Chem Biodivers ; 20(6): e202300309, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37222439

RESUMO

This work aimed to investigate Sinapis pubescens subsp. pubescens spontaneously grown in Sicily (Italy) as new potential source of active metabolites; specifically, a comparative study on leaf, flower, and stem hydroalcoholic extracts was performed. Polyphenols were quantitatively determined by spectrophotometric methods and characterized by HPLC-PDA/ESI-MS; a total of 55 polyphenolic compounds were identified, highlighting considerably different qualitative-quantitative profiles. The extracts showed antioxidant activity, evaluated by in vitro assays; particularly, the leaf extract displayed the best radical scavenging activity (DPPH test) and reducing power, while the flower extract showed the greatest chelating activity. The antimicrobial properties of the extracts were investigated against bacteria and yeasts by standard methods; no antimicrobial activity was found against the strains tested. The extracts resulted to be non-toxic after preliminary toxicity evaluation by the Artemia salina lethality bioassay. The aerial parts of S. pubescens subsp. pubescens proved to be valuable sources of antioxidants for pharmaceutical and nutraceutical applications.


Assuntos
Brassicaceae , Sicília , Brassicaceae/química , Sinapis , Extratos Vegetais/química , Fenóis/química , Antioxidantes/química , Componentes Aéreos da Planta/química
18.
BMC Complement Med Ther ; 23(1): 168, 2023 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-37226152

RESUMO

BACKGROUND: Essential oils are becoming increasingly popular in medicinal applications because of their antimicrobial effect. Thymus vulgaris L. (Lamiaceae) is a well-known and widely cultivated medicinal plant, which is used as a remedy for cold, cough and gastrointestinal symptoms. Essential oil content of thyme is responsible for its antimicrobial activity, however, it has been reported that the chemical composition of essential oils influences its biological activity. In order to explore flowering phenophases influence on the chemical composition of thyme essential oil and its antibacterial and anti-biofilm activity, plant materials were collected at the beginning of flowering, in full bloom and at the end of flowering periods in 2019. METHODS: Essential oils from fresh and dried plant materials were distilled and analyzed with gas chromatography-mass spectrometry (GC-MS) and gas chromatography-flame ionization detection (GC-FID). The antibacterial activity was performed by broth microdilution and thin layer chromatography-direct bioautography (TLC-DB) assays and the anti-biofilm effect by crystal violet assay, respectively. Scanning electron microscopy was applied to illustrate the cellular changes of bacterial cells after essential oil treatment. RESULTS: Thymol (52.33-62.46%) was the main component in the thyme essential oils. Thyme oil distilled from fresh plant material and collected at the beginning of flowering period exerted the highest antibacterial and anti-biofilm activity against Haemophilus influenzae, H. parainfluenzae and Pseudomonas aeruginosa. CONCLUSION: The different flowering periods of Thymus vulgaris influence the antibacterial and anti-biofilm activity of its essential oils, therefore, the collection time has to be taken into consideration and not only the full bloom, but the beginning of flowering period may provide biological active thyme essential oil.


Assuntos
Óleos Voláteis , Thymus (Planta) , Óleos Voláteis/farmacologia , Cromatografia Gasosa-Espectrometria de Massas , Antibacterianos/farmacologia
19.
Molecules ; 28(5)2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36903527

RESUMO

Recently, our research team has started a study on Brassica fruticulosa subsp. fruticulosa, an edible plant traditionally used to treat various ailments, little investigated to date. Good in vitro antioxidant properties were highlighted for the leaf hydroalcoholic extract, with the secondary higher than the primary ones. In continuation of the ongoing research, this work was designed to elucidate the antioxidant properties of the phenolic compounds contained in the extract. For this purpose, a phenolic-rich ethyl acetate fraction (Bff-EAF) was obtained from the crude extract by liquid-liquid extraction. The phenolic composition was characterized by HPLC-PDA/ESI-MS analysis and the antioxidant potential was investigated by different in vitro methods. Furthermore, the cytotoxic properties were evaluated by MTT, LDH and ROS determinations on human colorectal epithelial adenocarcinoma cells (CaCo-2) and human normal fibroblasts (HFF-1). Twenty phenolic compounds (flavonoid and phenolic acid derivatives) were identified in Bff-EAF. The fraction exhibited good radical scavenging activity in the DPPH test (IC50 = 0.81 ± 0.02 mg/mL), and moderate reducing power (ASE/mL = 13.10 ± 0.94) and chelating properties (IC50 = 2.27 ± 0.18 mg/mL), contrary to what previously observed for the crude extract. Bff-EAF reduced in a dose-dependent manner CaCo-2 cell proliferation after 72 h of treatment. This effect was accompanied by the destabilization of the cellular redox state due to the antioxidant and pro-oxidant activities displayed by the fraction at lower and higher concentrations. No cytotoxic effect was observed on HFF-1 fibroblasts, used as control cell line.


Assuntos
Antioxidantes , Brassica , Humanos , Antioxidantes/química , Sicília , Células CACO-2 , Extratos Vegetais/química , Fenóis/química , Folhas de Planta/química
20.
Anal Bioanal Chem ; 415(13): 2547-2560, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36629895

RESUMO

In this work, a solid-phase microextraction (SPME) Arrow method combined with comprehensive two-dimensional gas chromatography-mass spectrometry (GC × GC-MS) was developed for the elucidation of the volatile composition of honey samples. The sample preparation protocol was optimized to ensure high extraction efficiency of the volatile organic compounds (VOCs) which are directly associated with the organoleptic properties of honey and its acceptance by the consumers. Following its optimization, SPME Arrow was compared to conventional SPME in terms of sensitivity, precision, and number of extracted VOCs. The utilization of SPME Arrow fibers enabled the determination of 203, 147, and 149 compounds in honeydew honey, flower honey, and pine honey, respectively, while a significantly lower number of compounds (124, 94, and 111 for honeydew honey, flower honey, and pine honey, respectively) was determined using conventional SPME. At the same time, the utilization of SPME Arrow resulted in enhanced sensitivity and precision. All things considered, SPME Arrow and GC × GC-MS can be considered as highly suitable for the elucidation of the volatile composition of complex food samples resulting in high sensitivity and separation efficiency.


Assuntos
Mel , Compostos Orgânicos Voláteis , Cromatografia Gasosa-Espectrometria de Massas/métodos , Mel/análise , Microextração em Fase Sólida/métodos , Compostos Orgânicos Voláteis/análise
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