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1.
J Chromatogr A ; 1722: 464856, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38579610

RESUMO

Complex mixture analysis requires high-efficiency chromatography columns. Although reversed phase liquid chromatography (RPLC) is the dominant approach for such mixtures, hydrophilic interaction liquid chromatography (HILIC) is an important complement to RPLC by enabling the separation of polar compounds. Chromatography theory predicts that small particles and long columns will yield high efficiency; however, little work has been done to prepare HILIC columns longer than 25 cm packed with sub-2 µm particles. In this work, we tested the slurry packing of 75 cm long HILIC columns with 1.7 µm bridged-ethyl-hybrid amide HILIC particles at 2,100 bar (30,000 PSI). Acetonitrile, methanol, acetone, and water were tested as slurry solvents, with acetonitrile providing the best columns. Slurry concentrations of 50-200 mg/mL were assessed, and while 50-150 mg/mL provided comparable results, the 150 mg/mL columns provided the shortest packing times (9 min). Columns prepared using 150 mg/mL slurries in acetonitrile yielded a reduced minimum plate height (hmin) of 3.3 and an efficiency of 120,000 theoretical plates for acenaphthene, an unretained solute. Para-toluenesulfonic acid produced the lowest hmin of 1.9 and the highest efficiency of 210,000 theoretical plates. These results identify conditions for producing high-efficiency HILIC columns with potential applications to complex mixture analysis.


Assuntos
Acetonitrilas , Benzenossulfonatos , Interações Hidrofóbicas e Hidrofílicas , Acetonitrilas/química , Cromatografia Líquida/métodos , Cromatografia de Fase Reversa/métodos , Cromatografia de Fase Reversa/instrumentação , Metanol/química , Solventes/química , Acetona/química , Tamanho da Partícula , Pressão , Água/química
2.
Int J Med Sci ; 21(4): 593-600, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38464834

RESUMO

Introduction: Broccoli is a cruciferous vegetable that has been shown to have numerous potential therapeutic benefits because of its bioactive compounds. Methods: In this study, we compared the bioactive efficacy of cooked and uncooked (fresh) stems and florets of broccoli extracted with three different solvents: acetonitrile, methanol, and aqueous extracts. The extraction yield and antioxidant and antibacterial potential of different broccoli extracts were examined. Results: Fresh and boiled floret stem extracts increased the extraction yield. The extraction yields were higher for the methanol and acetonitrile extracts than for the aqueous extracts. The antioxidant efficacy of the different extracts was studied using ABTS, DPPH, and metal ion reduction assays. The acetonitrile and aqueous extracts exhibited higher antioxidant activities than the methanolic extracts in different antioxidant assays. In addition, increased antioxidant activity was observed in fresh florets and boiled broccoli stems. TPC and TFC contents were higher in the methanolic extracts than in the aqueous extracts. Similar to antioxidant activities, anti-inflammatory activities were found to be higher in the acetonitrile and aqueous extracts, particularly in boiled stems and fresh florets. Broccoli extracts have been shown to be active against Bacillus subtilis and moderately effective against Pseudomonas aeruginosa and Staphylococcus aureus. Conclusions: Acetonitrile and aqueous extraction of broccoli might be an ideal choice for extraction methods, which show increased extraction yield and antioxidant and anti-inflammatory potentials. Utilization of phytomolecules from natural sources is a promising alternative approach to synthetic drug development.


Assuntos
Brassica , Brassica/química , Antioxidantes/química , Metanol/química , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Água , Acetonitrilas , Anti-Inflamatórios
3.
Sci Rep ; 14(1): 7491, 2024 03 29.
Artigo em Inglês | MEDLINE | ID: mdl-38553576

RESUMO

The plants that we consume in our daily diet and use as a risk preventer against many diseases have many biological and pharmacological activities. In this study, the phytochemical fingerprint and biological activities of Beta vulgaris L. leaf extract, which are widely consumed in the Black Sea region, were investigated. The leaf parts of the plant were dried in an oven at 35 °C and then ground into powder. The main constituents in B. vulgaris were identified by LC-MS/MS and GC-MS analyses. Phenolic content, betaxanthin and betacyanin levels were investigated in the extracts obtained using three different solvents. The biological activity of the extract was investigated by anti-microbial, anti-mutagenic, anti-proliferative and anti-diabetic activity tests. Anti-diabetic activity was investigated by in vitro enzyme inhibition and in-silico molecular docking was performed to confirm this activity. In the LC-MS analysis of B. vulgaris extract, a major proportion of p_coumaric acid, vannilin, protecatechuic aldehyde and sesamol were detected, while the major essential oils determined by GC-MS analysis were hexahydrofarnesyl acetone and phytol. Among the solvents used, the highest extraction efficiency of 2.4% was obtained in methanol extraction, and 36.2 mg of GAE/g phenolic substance, 5.1 mg/L betacyanin and 4.05 mg/L betaxanthin were determined in the methanol extract. Beta vulgaris, which exhibited broad-spectrum anti-microbial activity by forming a zone of inhibition against all tested bacteria, exhibited anti-mutagenic activity in the range of 35.9-61.8% against various chromosomal abnormalities. Beta vulgaris extract, which did not exhibit mutagenic, sub-lethal or lethal effects, exhibited anti-proliferative activity by reducing proliferation in Allium root tip cells by 21.7%. 50 mg/mL B. vulgaris extract caused 58.9% and 55.9% inhibition of α-amylase and α-glucosidase activity, respectively. The interactions of coumaric acid, vanniline, hexahydrofarnesyl acetone and phytol, which are major compounds in phytochemical content, with α-amylase and α-glucosidase were investigated by in silico molecular docking and interactions between molecules via various amino acids were determined. Binding energies between the tested compounds and α-amylase were obtained in the range of - 4.3 kcal/mol and - 6.1 kcal/mol, while for α-glucosidase it was obtained in the range of - 3.7 kcal/mol and - 5.7 kcal/mol. The biological activities of B. vulgaris are closely related to the active compounds it contains, and therefore studies investigating the phytochemical contents of plants are very important. Safe and non-toxic plant extracts can help reduce the risk of various diseases, such as diabetes, and serve as an alternative or complement to current pharmaceutical practices.


Assuntos
Beta vulgaris , Diabetes Mellitus , Simulação de Acoplamento Molecular , Cromatografia Gasosa-Espectrometria de Massas , Metanol/química , Beta vulgaris/metabolismo , Cromatografia Líquida , 60705 , Acetona/análise , Ácidos Cumáricos/análise , alfa-Glucosidases/metabolismo , Betacianinas , Betaxantinas , Espectrometria de Massas em Tandem , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Solventes/química , alfa-Amilases , Compostos Fitoquímicos/química , Fitol , Antioxidantes/farmacologia
4.
Sci Rep ; 14(1): 5627, 2024 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-38454096

RESUMO

Plant extracts are actively being used worldwide due to the presence of biologically active constituents helping in the preservation of food, and to aid against various diseases owing to their antimicrobial and antioxidant potential. The present research work was carried out to investigate the phytochemical constituents, antimicrobial activity, and antioxidant activity of different extracted samples of Euphorbia parviflora. Anti-microbial studies were carried out by Agar well diffusion while the DPPH method was employed for investigating anti-oxidant activity. Three samples from methanol, chloroform, and ethyl acetate extract were tested against five different bacterial strains comprising two species from Gram-negative bacteria i.e., Staphylococcus aureus and Bacillus subtilis and three species from Gram-positive bacteria i.e. Escherichia coli, Pseudomonas aeruginosa and Klebsiella pneumonia along two fungal strains i.e. Candida albicans and Aspergillus niger. The results of the qualitative phytochemical analysis showed that methanolic, chloroformic, and ethylacetate extract of Euphorbia parviflora consist of alkaloids, reducing sugars, flavonoids, terpenoids, tannins, and saponins. The total phenol and flavonoid content of E. parviflora showed that the methanolic extract of E. parviflora had a significantly higher total phenolic content (53.73 ± 0.30 mg of GAE/g) and flavonoid content (44.62 ± 0.38 mg of than other extracts. The content of total phenolic and flavonoids was more in methanolic extract as compared to other extracts of E. prolifera. The HPLC analysis showed that in the chloroform extract of E. parviflora Cinnamic acid (4.32 ± 2.89 mg/g) was dominant, in methanol extract quercetin (3.42 ± 2.89 mg/g) was dominant and in ethyl acetate extract of E. parviflora catechin (4.44 ± 2.89 mg/g) was found dominant. The antimicrobial activity revealed that amongst all the extracts the highest antibacterial activity was shown by methanolic extract against B. subtilis and Staphylococcus aureus as compared to the other extracts. The antioxidant activity revealed that methanolic extract of E. parviflora demonstrated higher antioxidant activity (82.42 ± 0.02) followed by chloroform extract (76.48 ± 0.08) at 150 µg/mL. The aim of this study was primarily to evaluate the potential of this plant as a reliable source of antimicrobials and antioxidants that may be used for the treatment of various infectious diseases in the future. The study provides evidence that this plant can act as a reliable source of antimicrobial and antioxidant agents and might be used against several infectious diseases.


Assuntos
Acetatos , Anti-Infecciosos , Doenças Transmissíveis , Euphorbia , Euphorbiaceae , Antioxidantes/farmacologia , Antioxidantes/química , Metanol/química , Clorofórmio , Cromatografia Líquida de Alta Pressão , Anti-Infecciosos/farmacologia , Antibacterianos/farmacologia , Antibacterianos/química , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Compostos Fitoquímicos/farmacologia , Compostos Fitoquímicos/química , Flavonoides/análise , Fenóis/análise , Testes de Sensibilidade Microbiana
5.
Metabolomics ; 20(2): 38, 2024 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-38460055

RESUMO

INTRODUCTION: Changes in the categories and concentrations of salivary metabolites may be closely related to oral, intestinal or systemic diseases. To study salivary metabolites, the first analytical step is to extract them from saliva samples as much as possible, while reducing interferences to a minimum. Frequently used extraction methods are protein precipitation (PPT), liquid-liquid extraction (LLE) and solid-phase extraction (SPE), with various organic solvents. The types and quantities of metabolites extracted with different methods may vary greatly, but few studies have systematically evaluated them. OBJECTIVES: This study aimed to select the most suitable methods and solvents for the extraction of saliva according to different analytical targets. METHODS: An untargeted metabolomics approach based on liquid chromatography-mass spectrometry was applied to obtain the raw data. The numbers of metabolites, repeatability of the data and intensities of mass spectrometry signals were used as evaluation criteria. RESULTS: PPT resulted in the highest coverage. Among the PPT solvents, acetonitrile displayed the best repeatability and the highest coverage, while acetone resulted in the best signal intensities for the extracted compounds. LLE with the mixture of chloroform and methanol was the most suitable for the extraction of small hydrophobic compounds. CONCLUSION: PPT with acetonitrile or acetone was recommended for untargeted analysis, while LLE with the mixture of chloroform and methanol was recommended for small hydrophobic compounds.


Assuntos
Metabolômica , Metanol , Solventes/química , Metabolômica/métodos , Metanol/química , Espectrometria de Massas por Ionização por Electrospray/métodos , Clorofórmio , Acetona , Saliva , Acetonitrilas
6.
J Ethnopharmacol ; 328: 117991, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38460574

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Glinus oppositifolius (L.) Aug. DC. belongs to the family Molluginaceae, an annual prostrate herb traditionally used to treat inflammations, arthritis, malarial, wounds, fevers, diarrhoea, cancer, stomach discomfort, jaundice, and intestinal parasites. However, the anti-arthritic activity of the aerial part has still not been reported. AIM OF THE STUDY: To investigate the antioxidant and anti-arthritic activity of G. oppositifolius in Complete Freund's Adjuvant (CFA) induced rats. MATERIALS AND METHODS: The dried aerial parts of this plant material were defatted with n-hexane and extracted by methanol using a soxhlet apparatus. The in vitro anti-arthritic activity of methanolic extract of G. oppositifolius (MEGO) was evaluated in protein denaturation, membrane stabilization, and inhibition of proteinase assay at 25, 50, 100, 200, and 400 µg/ml concentrations. Female Wistar rats were immunized sub-dermally into the right hind paw with 0.1 ml of CFA. Rats were administered with MEGO at doses of 200 and 400 mg/kg once daily for fourteen days after arthritis induction. Assessment of arthritis was performed by measuring paw diameter, arthritic index, arthritic score, body weight, organ weight, and hematological and biochemical parameters, followed by the analysis of pro-inflammatory cytokines such as tumor necrosis factor-alpha (TNF-α), interleukin 6 (IL-6), interleukin-1-beta (IL-1ß), cyclooxygenase-2 (COX-2), interleukin 13 (IL-13) and interleukin 10 (IL-10) and histopathological study. In vivo antioxidant effect was investigated in enzymatic assays. The presence of phytoconstituents was analyzed by Gas Chromatography-Mass Spectrometry (GC-MS) and Liquid Chromatography-Mass Spectrometry (LC-MS), respectively. In silico molecular docking study of the compounds was carried out against COX-2, IL-1ß, IL-6, and TNF-α using AutoDock 4.2 and BIOVIA-Discovery Studio Visualizer software. RESULTS: MEGO's in vitro anti-arthritic activity showed dose-dependent inhibition of protein denaturation, membrane stabilization, and proteinase inhibition, followed by significant in vivo anti-arthritic activity. The rats treated with MEGO showed tremendous potential in managing arthritis-like symptoms by restoring hematological, biochemical, and histological changes in CFA-induced rats. MEGO (200 and 400 mg/kg) showed a significant alleviation in the levels of hyper expressed inflammatory mediators (TNF-α, IL-1ß, and IL-6) and oxidative stress (SOD, CAT, GSH, and LPO) in CFA-induced rats. Spergulagenin-A as identified by LC-MS analysis, exhibited the highest binding affinity against COX-2 (-8.6), IL-1ß (7.2 kcal/mol), IL-6 (-7.4 kcal/mol), and TNF-α (-6.5 kcal/mol). CONCLUSIONS: Provided with the comprehensive investigation, methanolic extract of G. oppositifolius against arthritic-like condition is a proof of concept that revalidates its ethnic claim. The presence of Spergulagenin-A might be responsible for the anti-arthritic activity.


Assuntos
Artrite Experimental , Molluginaceae , Ratos , Animais , Fator de Necrose Tumoral alfa , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Interleucina-6 , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Ratos Wistar , Ciclo-Oxigenase 2 , Simulação de Acoplamento Molecular , Quimiometria , Artrite Experimental/induzido quimicamente , Artrite Experimental/tratamento farmacológico , Metanol/química , Antioxidantes/uso terapêutico , Interleucina-13 , Peptídeo Hidrolases , Componentes Aéreos da Planta
7.
Sci Rep ; 14(1): 3469, 2024 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-38342928

RESUMO

The aim of this study was to investigate the potential of Ipomoea carnea flower methanolic extract (ICME) as a natural gastroprotective therapy against ethanol-induced gastric ulcers, particularly in individuals exposed to ionizing radiation (IR). The study focused on the Nrf2/HO-1 signaling pathway, which plays a crucial role in protecting the gastrointestinal mucosa from oxidative stress and inflammation. Male Wistar rats were divided into nine groups, the control group received distilled water orally for one week, while other groups were treated with ethanol to induce stomach ulcers, IR exposure, omeprazole, and different doses of ICME in combination with ethanol and/or IR. The study conducted comprehensive analyses, including LC-HRESI-MS/MS, to characterize the phenolic contents of ICME. Additionally, the Nrf2/HO-1 pathway, oxidative stress parameters, gastric pH, and histopathological changes were examined. The results showed that rats treated with IR and/or ethanol exhibited histopathological alterations, increased lipid peroxidation, decreased antioxidant enzyme activity, and reduced expression levels of Nrf2 and HO-1. However, pretreatment with ICME significantly improved these parameters. Phytochemical analysis identified 39 compounds in ICME, with flavonoids, hydroxybenzoic acids, and fatty acids as the predominant compounds. Virtual screening and molecular dynamics simulations suggested that ICME may protect against gastric ulceration by inhibiting oxidative stress and inflammatory mediators. In conclusion, this study demonstrates the potential of ICME as a natural gastroprotective therapy for preventing gastric ulcers. These findings contribute to the development of novel interventions for gastrointestinal disorders using natural plant extracts particularly in individuals with a history of radiation exposure.


Assuntos
Extratos Vegetais , Úlcera Gástrica , Animais , Ratos , Antioxidantes/farmacologia , Etanol/química , Mucosa Gástrica/metabolismo , Metanol/química , Fator 2 Relacionado a NF-E2/metabolismo , Extratos Vegetais/química , Extratos Vegetais/uso terapêutico , Ratos Wistar , Úlcera Gástrica/tratamento farmacológico , Úlcera Gástrica/etiologia , Úlcera Gástrica/prevenção & controle , Espectrometria de Massas em Tandem , Úlcera/patologia
8.
Chem Biodivers ; 21(3): e202301474, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38215210

RESUMO

The present study shows the untargeted metabolite profiling and in vitro antibacterial, cytotoxic, and nitric oxide (NO) inhibitory activities of the methanolic leaves extract (MLE) and methanolic stem extract (MSE) of Erythroxylum mexicanum, as well as the fractions from MSE. Using ultra-high performance liquid chromatography/quadrupole time-of-flight tandem mass spectrometry (UHPLC-QTOF-MS/MS), a total of 70 metabolites were identified; mainly alkaloids in the MLE, while the MSE showed a high abundance of diterpenoids. The MSE fractions exhibited differential activity against Gram-positive bacteria. Notably, the hexane fraction (HSF) against Streptococcus pyogenes ATCC 19615 (MIC=62.5 µg/mL) exhibited a bactericidal effect. The MSE fractions exhibited cytotoxicity against all cancer cell lines tested, with selectivity towards them compared to a noncancerous cell line. Particularly, the HSF and chloroform fraction (CSF) showed the highest cytotoxicity against prostate cancer (PC-3) cells, with IC50 values of 19.9 and 18.1 µg/mL and selectivity indexes of 3.8 and 4.2, respectively. Both the HSF and ethyl acetate (EASF) fractions of the MSE inhibited NO production in RAW 264.7 macrophages, with NO production percentages of 50.0 % and 51.7 %, respectively, at a concentration of 30 µg/mL. These results indicated that E. mexicanum can be a source of antibacterial, cytotoxic, and anti-inflammatory metabolites.


Assuntos
Antineoplásicos , Espectrometria de Massas em Tandem , Masculino , Humanos , Óxido Nítrico , Extratos Vegetais/química , Cromatografia Líquida de Alta Pressão , Antibacterianos/farmacologia , Antineoplásicos/farmacologia , Metanol/química
9.
Chem Biodivers ; 21(3): e202400040, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38265183

RESUMO

Many Vicia species (Fabaceae) were proven to possess bioactive compounds with potential health beneficial properties. The present study was designed to determine the phenolic constituents, antioxidant and enzyme inhibition activities of aerial parts and seed of V. peregrina. Hexane, ethyl acetate and methanol extracts were prepared by maceration and aqueous extract by infusion. The chemical compositions of the extracts were determined using HPLC-MS/MS technology. The antioxidant activities were examined using various assays including free radical scavenging (ABTS and DPPH), reducing ability (CUPRAC and FRAP), metal chelation, and phosphomolybdenum. The enzyme inhibitory effects were investigated against cholinesterase, tyrosinase, amylase and glucosidase. The highest total phenolics and flavonoids contents were recorded in the methanol extracts of the seed (45.42 mg GAE/g) and aerial parts (40.33 mg RE/g) respectively. The aerial parts were characterized by higher accumulation of chlorogenic acid (9893.86 µg g-1 ), isoquercitrin (9400.33 µg g-1 ), delphindin 3,5 diglucoside (9113.28 µg g-1 ), hyperoside (6337.09 µg g-1 ), rutin (3489.83 µg g-1 ) and kaempferol-3-glucoside (2872.84 µg g-1 ). Generally, the methanol and aqueous extracts of the two studied parts exerted the best antioxidant activity with highest anti-DPPH (61.99 mg TE/g), anti-ABTS (101.80 mg TE/g) and Cu++ (16169 mg TE/g) and Fe+++ (172,36 mg TE/g) reducing capacity were recorded from the seed methanol extract. Methanol extract of the seed showed the best anti-tyrosinase activity (75.86 mg KAE/g). These results indicated that V. peregrina is rich with bioactive phenolics suggesting their use in different health promoting applications.


Assuntos
Antioxidantes , Vicia , Antioxidantes/farmacologia , Antioxidantes/química , Metanol/química , Hipoglicemiantes/farmacologia , Espectrometria de Massas em Tandem , Turquia , 60705 , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Fenóis/química
10.
J Microbiol Biotechnol ; 34(1): 94-102, 2024 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-38282409

RESUMO

Plants contain a large number of phytochemical components, many of which are known as bioactive compounds and responsible for the expression of various pharmacological activities. The extract of Sonneratia caseolaris fruit collected in Vietnam was investigated for its total phenolic and total flavonoid contents using methanol solvent and different fractions of S. caseolaris fruits (hexane, ethyl acetate, n-butanol, and aqueous). GC-MS analysis was conducted to identify the bioactive chemical constituents occurring in the active extract. Further, the antibacterial activity was tested in vitro on bacterial isolates, namely Escherichia coli, Staphylococcus aureus, and Bacillus subtilis, using the disc diffusion method on tryptic soya agar (TSA) medium. The methanol extract showed high total flavonoid (82.3 ± 0.41 mg QE/g extract) and phenolic (41.0 ± 0.34 mg GAE/g extract) content. GC-MS of the methanol extract and different fractions of S. caseolaris fruits detected 20 compounds, principally fatty alcohols, fatty acids, phenols, lipids, terpenes derivatives, and carboxylic acids derivatives. A 50 mg/ml concentration of methanol extract had the strongest antibacterial activity on E. coli, S. aureus, and B. subtilis. Furthermore, ethyl acetate, aqueous, and n-butanol fractions inhibited S. aureus and B. subtilis the most. The results of the present study suggested that the fruits of S. caseolaris are rich sources of phenolic compounds that can contribute to safe and cost-effective treatments.


Assuntos
Acetatos , Frutas , Polifenóis , Polifenóis/análise , Polifenóis/farmacologia , Frutas/química , Extratos Vegetais/química , Metanol/química , Cromatografia Gasosa-Espectrometria de Massas , Staphylococcus aureus , Vietnã , 1-Butanol/farmacologia , Escherichia coli , Antioxidantes/farmacologia , Antibacterianos/farmacologia , Antibacterianos/análise , Fenóis/farmacologia , Flavonoides/farmacologia
11.
J Mol Graph Model ; 128: 108705, 2024 05.
Artigo em Inglês | MEDLINE | ID: mdl-38277857

RESUMO

A set of forty hybrid functionals, combined with a 6-31++G(d,p) basis set and an IEFPCM solvent description, was applied to calculate the S0→S1 excitation of the spironaphthopyran (SNP) photochromic compound. None of the hybrid functionals resulted in Cspiro-O bond cleavage upon optimization of the S1 excited state of the SNP, in contrast to the spiropyran BIPS which we studied earlier. At the same time, the deformations of the SNP during excitation turned out to be very small (in contrast to those for BIPS) which made it possible to calculate its vibronic absorption spectrum. The best agreement between the calculated and experimental absorption bands was demonstrated by the SOGGA11X functional. The main result of this work is confirmation of the vibration participation in the breaking of the Cspiro-O bond in the S1 excited state of the SNP. This assumption based on experimental data was previously put forward by other authors. Strong H-bonds between the SNP and two methanol molecules enhance the photoinduced distortions of the latter and are slightly weakened upon excitation.


Assuntos
Metanol , Teoria Quântica , Metanol/química , Teoria da Densidade Funcional , Ligação de Hidrogênio , Solventes/química
12.
J Chromatogr A ; 1715: 464629, 2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38183782

RESUMO

Rosin-based chromatographic columns are widely used for separation purposes, but, to date, their phase ratios (Φ) have been imprecisely measured. This affects the understanding of their separation mechanism and the calculation of related thermodynamic parameters. In this study, a stationary phase was synthesized by bonding dehydroabietic acid (DA) to silica gel (Si-DO) and applied for reversed-phase liquid chromatography. The distribution coefficient (Kdm) of methyl dehydroabietate (MD), which has the same structure as the bonded phase of Si-DO, was used as a surrogate for the determination of the equilibrium coefficient (K) of Si-DO, and the Kdm values of MD in different mobile phases were measured and compared with the K values of Si-DO. It was found that the phase ratio of Si-DO varied with mobile phase composition and temperature, as shown by the Φ values: 0.039-0.122 for the methanol/water system and 0.051-0.116 for the acetonitrile/water system; in addition, the a indices were 0.552-0.757 and 0.564-0.674, respectively. The Kdm of MD was closer to the K of Si-DO than those of other surrogate models, including the octanol-water and octane-mobile phase partition coefficients. In addition, the thermodynamic parameters (ΔG°, ΔH°, and ΔS°) of n-alkylbenzenes on Si-DO were negative, indicating a spontaneous and enthalpy-driven separation process. Overall, the phase ratio of rosin-based columns is crucial for accurate thermodynamic analysis and interpretation of the separation mechanism. Finally, the MD surrogate model allows the estimation of phase ratio of Si-DO and other similar columns, providing a novel method for measuring the phase ratio of rosin-based columns and providing a validated concept and methodology for determining the phase ratios of HPLC columns.


Assuntos
Metanol , Dióxido de Silício , Dióxido de Silício/química , Termodinâmica , Metanol/química , Água/química , Cromatografia de Fase Reversa/métodos , Cromatografia Líquida de Alta Pressão/métodos
13.
Biomed Chromatogr ; 38(3): e5808, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38191948

RESUMO

Thymus linearis (Thyme) is a medicinal plant widely distributed throughout Asia. Various parts of thyme are utilized for diverse medicinal purposes, including its use as a tonic and diuretic, for cough relief, as a flavoring agent, in treating dysentery, and for alleviating stomach disorders. Numerous studies have been conducted to explore the unexploited potential of thyme. Thyme was collected from the northern region of Pakistan, and sun-mediated extraction was conducted. Phytochemical analysis, utilizing GC-MS, revealed numerous bioactive phytochemical constituents with disease-preventing roles, including detoxifying agents, antioxidants, anticancer compounds, dietary fiber, neuropharmacological agents, and immunity-potentiating agents, in the methanolic and ethanolic (14 days) extracts of the flower, leaf, and stem. The 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay results indicated that the ethanolic and methanolic extracts of the stem exhibited the highest antioxidant activity, reaching up to 67.34% and 62.73%, respectively, while the values for the flower and leaf extracts (both methanol and ethanol) were around 60%. The IC50 (half maximal inhibitory concentration) values were also calculated for all the samples, ranging between 7 and 9 µg/mL. Positive antibacterial and antifungal effects against Bacillus subtilis and Escherichia coli, as well as Aspergillus niger (fungi), were observed only in the extracts of the flower (both methanol and ethanol). The sun-mediated technique was used for extraction for the first time in this study. Therefore, this study introduces a novel approach to the extraction of bioactive compounds from medicinal plants, ultimately contributing to the development of herbal drugs with more convenient and cost-effective methods.


Assuntos
Plantas Medicinais , Thymus (Planta) , Antioxidantes/farmacologia , Antioxidantes/química , Metanol/química , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Thymus (Planta)/química , Antibacterianos/farmacologia , Antibacterianos/química , Plantas Medicinais/química , Compostos Fitoquímicos/farmacologia , Etanol
14.
Nat Prod Res ; 38(4): 634-638, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-36799649

RESUMO

In connection to search for safe and alternative plant-based drugs, the wound healing mechanisms of an Indian ethnomedicine Couroupita guianensis fruit pulp was analyzed in this project work. Gas chromatography coupled with mass spectrometer (GC-MS) analysis revealed the existence of phytochemicals such as 2-furoic acid, 2,4-heptadienal, pyrazole and 8-hydroxyquinoline in the methanol extract. Methanol extract of C. guianensis exhibited remarkable radical scavenging activity against 2, 2-diphenyl-1-picrylhydrazyl (DPPH) (89.88%), superoxide (91.51%), hydrogen peroxide (24.25%) and hydroxyl radicals (73.62%). Further, it showed remarkable anti-inflammatory (24.09-62.16%) and anti-bacterial activity (zone of inhibition, ZOI: 13.00 mm, minimum inhibitory concentration, MIC: 6.25 mg/mL and minimum bactericidal concentration, MBC: 12.51 mg/mL) and also controlled the growth rate of methicillin resistant Staphylococcus aureus (MRSA) within 30 min of treatment. The angiogenic potential of C. guianensis was proved in chick chorioallantoic membrane (CAM) model and it does not exhibit any toxicity in peripheral blood monocyte cells (PBMC) model.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Extratos Vegetais , Humanos , Extratos Vegetais/química , Antibacterianos/química , Metanol/química , Profissionais de Medicina Tradicional , Antioxidantes/farmacologia , Frutas/química , Leucócitos Mononucleares , Cicatrização , Testes de Sensibilidade Microbiana , Medicina Tradicional
15.
Appl Biochem Biotechnol ; 196(2): 729-773, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37184725

RESUMO

Aloe barbadensis Miller (ABM) is a traditional medicinal plant all over the world. Numerous studies were conducted to exhibit its medicinal properties and most of them were concentrated on its metabolites against human pathogens. The current research work evaluates the attributes of different polar-based extracts (ethanol, methanol, ethyl acetate, acetone, hexane, and petroleum ether) of dried Aloe barbadensis leaf (ABL) to investigate its phytochemical constituents, antioxidant potential (DPPH, ABTS), phenolic, tannin, flavonoid contents, identification of bioactive compounds, and functional groups by gas chromatography-mass spectrometry (GC-MS) and fourier transform infrared spectroscopy (FT-IR) respectively, and comparing antibacterial efficacy against human pathogens, aquatic bacterial pathogens, and zoonotic bacteria associated with fish and human. The present results showed that the methanolic extract of ABL showed higher antioxidant activity (DPPH-59.73 ± 2.01%; ABTS-74.1 ± 1.29%), total phenolic (10.660 ± 1.242 mg GAE/g), tannin (7.158 ± 0.668 mg TAE/g), and flavonoid content (49.545 ± 1.928 µg QE/g) than that of other solvent extracts. Non-polar solvents hexane and petroleum ether exhibited lesser activity among the extracts. In the case of antibacterial activity, higher inhibition zone was recorded in methanol extract of ABL (25.00 ± 0.70 mm) against Aeromonas salmonicida. Variations in antibacterial activity were observed depending on solvents and extracts. In the current study, polar solvents revealed higher antibacterial activity when compared to the non-polar and the mid-polar solvents. Diverse crucial bioactive compounds were detected in GC-MS analysis. The vital compounds were hexadecanoic acid (30.69%) and 2-pentanone, 4-hydroxy-4-methyl (23.77%) which are responsible for higher antioxidant and antibacterial activity. Similar functional groups were identified in all the solvent extracts of ABL with slight variations in the FT-IR analysis. Polar-based solvent extraction influenced the elution of phytocompounds more than that of the other solvents used in this study. The obtained results suggested that the ABM could be an excellent source for antioxidant and antibacterial activities and can also serve as a potential source of effective bioactive compounds to combat human as well as aquatic pathogens.


Assuntos
Alcanos , Aloe , Antioxidantes , Benzotiazóis , Ácidos Sulfônicos , Animais , Humanos , Antioxidantes/farmacologia , Antioxidantes/química , Taninos , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Cromatografia Gasosa-Espectrometria de Massas , Hexanos , Metanol/química , Espectroscopia de Infravermelho com Transformada de Fourier , Antibacterianos/farmacologia , Antibacterianos/química , Solventes/química , Compostos Fitoquímicos/farmacologia , Compostos Fitoquímicos/química , Flavonoides/farmacologia
16.
Environ Res ; 242: 117764, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38029820

RESUMO

An in-vitro investigation was performed to evaluate and compare the phytochemical, antioxidant, antidiabetic, anti-inflammatory, and anti-lung cancer activities of methanol extracts of aerial parts of Andrographis paniculata and Trianthema portulacastrum. Furthermore studied major functional groups of phytochemicals present in the methanol extracts of these plants through Fourier transform infrared (FTIR) analysis. The results showed that the methanol extract of A. paniculata contain more number of pharmaceutically valuable phytochemicals such as alkaloids, flavonoids, terpenoids, saponin, glycoside, phytosterol, and tannin than T. portulacastrum. Similar way the methanol extract of A. paniculata showed considerable dose dependent antioxidant (DPPH: 63%), antidiabetic (α-amylase: 82.31% and α-glucosidase inhibitions: 72.34%), and anti-inflammatory (albumin-denaturation inhibition: 76.3% and anti-lipoxygenase: 61.2%) activities (at 900 µg mL-1 concentration) than T. portulacastrum. However, the anti-lung cancer activities of these test plants against A549 cells were not considerable. According to FTIR analysis, the A. paniculata methanol extract has a larger number of characteristic peaks attributed to the active functional groups of pharmaceutically valuable bioactive components that belong to different types of phytochemicals. These findings imply that A. paniculata methanol extracts can be used for additional research, such as bioactive compound screening and purification, as well as assessing their potential biomedical uses in various in-vitro and in-research settings.


Assuntos
Andrographis , Neoplasias , Humanos , Hipoglicemiantes/farmacologia , Andrographis paniculata , Metanol/química , Antioxidantes/farmacologia , Andrographis/química , Anti-Inflamatórios/farmacologia , Extratos Vegetais/farmacologia , Extratos Vegetais/química
17.
J AOAC Int ; 107(1): 46-51, 2024 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-37831814

RESUMO

BACKGROUND: Its broad applicability and capacity to separate numerous components in a single chromatographic run led to the initial recognition of reversed-phase (RP)-HPLC as an analytical technique. OBJECTIVE: The objective of this study was to create a straightforward and reliable method for accurately and precisely measuring the amount of tapinarof in both the topical formulation and the active pharmaceutical ingredient. Additionally, a robust HPLC assay was developed specifically for analyzing the topical formulation. METHODS: In this study, chromatographic analysis was conducted using a Kromosil C18 column with dimensions of 250 × 4.6 mm and a particle size of 5 microns. The mobile phase consisted of a phosphate buffer and methanol in a ratio of 100:900 (v/v). The flow rate was set at 1.0 mL/min, with an injection volume of 10 µL and a run time of 6 min using isocratic elution. UV detection was performed at a wavelength of 313 nm, and the temperature was maintained at 30°C. The analysis showed well-separated peaks with a high number of theoretical plates, a low tailing factor, and consistent retention time. Validation of the method was conducted, and all validation parameters were found to be within the acceptable limits. RESULTS: A method that is simple, accurate, and precise has been developed to estimate the amount of tapinarof in a topical formulation and active pharmaceutical ingredient. The optimized method involved the use of a column temperature set at 30°C, 90% methanol as the mobile phase, and a flow rate of 1.0 mL/min. The retention time for tapinarof was determined to be 2.88 min. The method exhibited linearity in the concentration range of 5 to 30 µg/mL (with an R2 value greater than 0.999) for tapinarof. CONCLUSION: The topical formulated cream and active pharmaceutical ingredient showed more than 90% dissolution within 5 min. The method developed in this study utilized photo diode array (PDA) for peak integrity and purity confirmation, making it suitable for the quantification of tapinarof in both topical formulations and active pharmaceutical ingredients. HIGHLIGHTS: The method was validated and can be recommended for routine analysis in QC laboratories.


Assuntos
Estilbenos , Metanol/química , Resorcinóis , Cromatografia Líquida de Alta Pressão/métodos
18.
Chemosphere ; 349: 140898, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38070610

RESUMO

Influence of the cosolvent on the sorption of organic acids on biochar has not been well understood. For this purpose, the sorption (log Km, L kg-1) of three aromatic acids (benzoic acid (BA, pKa = 4.20), 1-naphthoic acid (1-NAPA, pKa = 3.70), and 9-anthroic acid (9-ANTA, pKa = 3.65) was evaluated as a function of methanol volume fraction (fc = 0.0, 0.25, and 0.5), liquid pH (2.5 and 7.0), ionic composition (CaCl2 and KCl) and ionic strength (0.005 M, 0.5 M, and 1 M CaCl2). A giant Miscanthus-derived biochar (ZPC of 2.86) was used as the sorbent. For all solutes, the sorption coefficients (log Km) measured at pH 2.5 (i.e., pH < pKa) tended to decrease with increasing fc, as expected from the cosolvency model, while the result obtained at pH 7.0 was not fully explained by the same model. The log Km of 1-NAPA in the CaCl2 system was always greater than in the KCl system (p < 0.05) and the impact became pronounced at high pH (>pKa) with increasing fc. Increasing the Ca2+ concentration at fc = 0.0 (from 0.005 M to 1 M) enhanced the value by 0.32 log unit of Km. These phenomena indicate a significant role of dissolved Ca2+ in the liquid phase, most likely due to the formation of cation bridges between aromatic carboxylates and the biochar surface (i.e., [R-COO--Ca2+]-{Biochar-}). A decrease in the dielectric constant of the methanol mixture could fortify the formation of this bridge. Regardless of the degree of cosolvency power (σ), as the number of aromatic rings of solutes increases, Km decreases in the order BA > 1-NAPA > 9-ANTA, where fc = 0.0. In conclusion, the sorption potential of biochar can be significantly weakened by increasing pH and fc, and in the absence of a divalent cation.


Assuntos
Ácido Benzoico , Metanol , Ácido Benzoico/química , Metanol/química , Cloreto de Cálcio , Carvão Vegetal , Soluções , Adsorção
19.
Chemosphere ; 349: 140890, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38072201

RESUMO

There is much interest in developing metal-free halogenated graphene such as fluorinated graphene for various catalytic applications. In this work, a fluorine-doped graphene oxide photocatalyst was investigated for photocatalytic oxidation (PCO) of a volatile organic compound (VOC), namely gaseous methanol. The fluorination process of graphene oxide (GO) was carried out via a novel and facile solution-based photoirradiation method. The fluorine atoms were doped on the surface of the GO in a semi-ionic C-F bond configuration. This presence of the semi-ionic C-F bonds induced a dramatic 7-fold increment of the hole charge carrier density of the photocatalyst. The fluorinated GO photocatalyst exhibited excellent photodegradation up to 93.5% or 0.493 h-1 according pseudo-first order kinetics for methanol. In addition, 91.7% of methanol was mineralized into harmless carbon dioxide (CO2) under UV-A irradiation. Furthermore, the photocatalyst demonstrated good stability in five cycles of methanol PCO. Besides methanol, other VOCs such as acetone and formaldehyde were also photodegraded. This work reveals the potential of fluorination in producing effective graphene-based photocatalyst for VOC removal.


Assuntos
Grafite , Compostos Orgânicos Voláteis , Grafite/química , Metanol/química , Flúor/química
20.
Nat Prod Res ; 38(1): 135-139, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-35895027

RESUMO

Swertia perennis Linnaeus (SP) has been utilised to treat gastritis. We report the qualitative and quantitative phytochemical analysis, antioxidant and enzyme inhibitory activities of SP. The correlation between the biological activities and total bioactive contents of the extracts was also studied via multivariate analysis. Methanol extract contained many active compounds and exhibited good antioxidant activity. Therefore, this was selected for further phytochemical profiling and stability studies. Fourteen compounds were identified by ultra-performance liquid chromatography-electrospray ionisation-orbitrap-mass spectrometry for the first time from this plant. Iridoids, xanthones, and flavonoids were the main components. Methanol extract exhibited good stability and antioxidant capacity in stability studies, with low toxicity, and showed a protective effect on the oxidation of olive and sunflower oils. SP has the potential to be developed and used as an antioxidant, or as urease and XO inhibitors, and its methanol extract could be used as a natural oil stabiliser.


Assuntos
Antioxidantes , Swertia , Antioxidantes/química , Extratos Vegetais/química , Swertia/química , Metanol/química , Flavonoides/química , Componentes Aéreos da Planta/química , Compostos Fitoquímicos/análise , Análise Multivariada
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