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1.
Phytochem Anal ; 33(7): 999-1017, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35733081

RESUMO

INTRODUCTION: Medical uses of Cannabis sativa L. have gained interest in recent decades, which highlights the need for defining appropriate quality specifications for Cannabis-based products. However, the complexity of plant matrices and structural similarity between cannabinoids make analytical development a challenging task. Thus, the application of analytical quality by design (AQbD)-driven approaches can favour the development of fit-for-purpose methods. OBJECTIVES: To develop a high-performance liquid chromatography diode array detector (HPLC-DAD) method for simultaneous quantification of cannabidiol, Δ9 -tetrahydrocannabinol, cannabidiolic acid, tetrahydrocannabinolic acid, and cannabinol in C. sativa by applying an AQbD-driven approach. MATERIALS AND METHODS: Critical method attributes (CMA) were established following the analytical target profile. Critical method variables (CMV) were categorised based on risk assessment and literature review. Selected CMV regarding sample preparation and chromatographic conditions were optimised using response surface methodology (RSM). The working point was estimated by multiple response optimisation using Deringer's desirability function. The validity of the optimal conditions was confirmed experimentally. Method validation was performed according to ANVISA and ICH guidelines. Relative response factors (RRFs) were also determined. RESULTS AND DISCUSSION: Baseline resolution of 12 major cannabinoids was achieved in a 35 min chromatographic analysis. All experimental responses obtained during confirmatory analyses were within the prediction intervals (PI95% ). Method's selectivity, linearity (10-100 µg/mL), precision, bias, extraction recovery, and ruggedness were satisfactorily demonstrated. CONCLUSIONS: The application of an AQbD-driven approach allowed for a better understanding of the effects of the ensemble of CMV on the analyte's behaviour, enabling the definition of appropriate conditions to ensure consistent achievement of the intended method's performance.


Assuntos
Canabidiol , Canabinoides , Cannabis , Infecções por Citomegalovirus , Canabidiol/análise , Canabinoides/análise , Canabinol/análise , Cannabis/química , Cromatografia Líquida de Alta Pressão/métodos , Dronabinol/análise , Dronabinol/química , Extratos Vegetais/química
2.
Artigo em Inglês | MEDLINE | ID: mdl-35447522

RESUMO

Psidium cattleyanum has two morphotypes: one with yellow fruits and other with red fruits. The leaves are popularly used as anti-inflammatory. However, no distinction is made between the types. Therefore, this study compared chemical and pharmacological data of both morphotypes to select proper biomarkers to ensure P. cattleyanum leaves quality. After extraction optimization by experimental design, 28 samples were analyzed by HPLC. Using Principal Component Analysis, it was possible to detect two chemotypes, unrelated to the color of the fruits. However, the extracts obtained from both chemotypes seemed to play similar anti-inflammatory effect, demonstrated by anti-chemotactic activity. The compounds common to both chemotypes were isolated and identified as hyperoside, miquelianin and quercitrin; these compounds also demonstrated anti-inflammatory potential. Since both chemotypes played similar activity, along with the isolated flavonoids, these flavonoids were selected as biomarkers for quality control of P. cattleyanum leaves. Following ICH guidelines, a HPLC method was validated. In summary, this study demonstrated that hyperoside, miquelianin and quercitrin can be used as biomarkers for quality control of P. cattleyanum leaves and a method was developed and validated to be used interchangeably for both morpho- and chemotypes.


Assuntos
Psidium , Biomarcadores/análise , Flavonoides/análise , Frutas/química , Extratos Vegetais/química , Folhas de Planta/química , Psidium/química
4.
Biomed Chromatogr ; 35(5): e5053, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33314218

RESUMO

Atropine is an antimuscarinic alkaloid identified in Atropa belladonna. In pharmacopeias, percolation is standardized as an extraction method for A. belladonna leaves, along with liquid-liquid extraction as a cleanup procedure and titration as an analytical method for assaying the atropine in the leaves. In this study, a faster, solvent-saving, and more reliable method for quality control of A. belladonna samples was developed. Ultrasound-assisted extraction was proposed and optimized by fractional factorial design followed by Box-Behnken design. For modeling atropine content, the following optimal conditions were established: particle size, 180 µm; percentage methanol in water, 50%; volume of solvent, 15 ml; time of extraction, 60 min; and number of extractions, two. This led to a significant improvement in atropine extraction (P < 0.001). For cleanup, solid-phase extraction was used as an alternative to liquid-liquid extraction, giving similar results, with higher reproducibility. Finally, for the atropine assay, a UPLC method was validated as a substitute for the classic titration method. Taken together, the development of an ultrasound-assisted extraction-solid-phase extraction-UPLC approach allowed the determination of atropine content in A. belladonna leaves in a time- and solvent-saving manner, with high reliability.


Assuntos
Atropa belladonna/química , Atropina/análise , Cromatografia Líquida de Alta Pressão/métodos , Extratos Vegetais/química , Folhas de Planta/química , Extração em Fase Sólida/métodos , Antagonistas Muscarínicos/análise , Solventes/química
5.
Talanta ; 216: 120988, 2020 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-32456919

RESUMO

Cuphea glutinosa is a medicinal species abundant in South of Brazil, known because of its flavonoids, which have pharmacological properties as antioxidant, anti-hypertensive, diuretic, and antimicrobial. The present study aimed to optimize the extraction and validate an ultra-performance liquid chromatographic method coupled to a photodiode array detector (UPLC-PDA) method for the quantification of a chemical marker miquelianin in C. glutinosa leaves. The optimum conditions for the extraction of miquelianin from leaves of C. glutinosa were determined using a fractional factorial design (FFD) and a central composite design (CCD). An UPLC-PDA method was validated, following the ICH guidelines and RDC 166/2017 of ANVISA (Brazil). The extraction-optimization methodology was obtained with the following parameters: plant:solvent 1:60 (w/v), percentage solvent 38% ethanol, 60 min time, five extractions and particle size ≤ 180 µm. The validation parameters of the quantification method were satisfactory. The results revealed a method with excellent selectivity, linearity, precision (repeatability and intermediate precision were below 2.18 and 1.40%, respectively) and accuracy (mean recovery 90.6%). The average content of miquelianin was 1.03%. Briefly, the optimization of the extractive method in the leaves of C. glutinosa increased the concentration of miquelianin in the crude extract and the method was validated according to the current legislation.


Assuntos
Cuphea/química , Glucosídeos/análise , Folhas de Planta/química , Quercetina/análogos & derivados , Ondas Ultrassônicas , Cromatografia Líquida de Alta Pressão , Quercetina/análise
6.
Planta Med ; 86(2): 151-159, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31777054

RESUMO

The biological properties of Achyrocline satureioides have been mostly ascribed to its major flavonoids quercetin (QCT), luteolin (LUT), and 3-O-methylquercetin (3OMQ). The present study aimed to optimize the extraction by dynamic maceration of the major phenolic compounds in order to obtain in a subsequent step a flavonoid-enriched fraction (FEF) using high performance countercurrent chromatography (HPCCC). A 3-level Box-Behnken design (BBD) was applied to maximize the extraction of the substances, using the plant : solvent ratio (X1 ), extraction time (X2 ), and ethanol concentration (X3 ) as factors. One-step HPCCC semipreparative separation with a solvent system composed of hexane : ethyl acetate : methanol : water (0.9 : 0.9 : 0.8 : 1.0, v/v) was employed to obtain the FEF. The second-order polynomial model was able to fit the experimental data adequately. The linear and quadratic terms of X3 were the most significant factors that affected all the responses. The positive linear term of X3 indicated a substantial increase in extraction yield, while the negative quadratic term showed a nonlinear tendency. Linear terms of X1 suggested a tendency to solvent saturation, except for QCT. The terms of X2 did not affect the responses substantially. The HPCCC method was found to be efficient and rapid for separating the FEF with 71% (w/w) flavonoid content. Overall, the developed extraction procedure coupled with HPCCC proved to be efficient for obtaining an enriched fraction with a very high content of flavonoids from A. satureioides.


Assuntos
Achyrocline/química , Distribuição Contracorrente/métodos , Flavonoides/isolamento & purificação , Extratos Vegetais/isolamento & purificação
7.
Nutrition ; 70: 110579, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31743815

RESUMO

OBJECTIVES: Pulmonary arterial hypertension (PAH) is a condition characterized by an increased resistance of pulmonary vasculature, culminating in an increase in pulmonary pressure. This process involves disturbances in lung redox homeostasis, causing progressive right heart failure. In this context, the use of natural antioxidants, such as those found in blueberries, may represent a therapeutic approach. The aim of this study was to evaluate the effect of blueberry extract (BB) on functional parameters and oxidative stress levels in rat lungs with induced PAH. METHODS: Forty-eight male Wistar rats (weighing 200 ± 20 g) were randomized into five groups: control, monocrotaline, monocrotaline + BB 50, monocrotaline + BB 100, and monocrotaline + BB 200. PAH was induced by the administration of monocrotaline (60 mg/kg, intraperitoneal). Rats were treated with BB at doses of 50, 100, and 200 mg/kg via gavage for 5 wk (2 wk before monocrotaline and 3 wk after monocrotaline injection). At day 35, rats were submitted to echocardiography and catheterization. They were then sacrificed and lungs were harvested for biochemical analyses. RESULTS: BB increased the E/A ratio of blood flow across the tricuspid valve and tricuspid annular phase systolic excursion, as wells as decreased the mean pulmonary artery pressure of animals compared with the PAH group. Moreover, BB decreased total reactive species concentration and lipid oxidation, reduced activity of nicotinamide adenine dinucleotide phosphate oxidase and expression of xanthine oxidase, increased the activity of superoxide dismutase and restored sulfhydryl content in the animal lungs compared with those in the PAH group. Additionally, BB restored expression of the antioxidant transcriptional factor Nrf2 in the lungs of the animal subjects. Finally, BB normalized the endothelin receptor (ETA/ETB) expression ratio in the animal lungs, which were increased in the PAH group. CONCLUSION: Intervention with BB mitigated functional PAH outcomes through improvement of the pulmonary redox state. Our results provide a basis for future research on natural antioxidant interventions as a novel treatment strategy in PAH.


Assuntos
Antioxidantes/farmacologia , Pressão Arterial/efeitos dos fármacos , Mirtilos Azuis (Planta)/química , Extratos Vegetais/farmacologia , Hipertensão Arterial Pulmonar/tratamento farmacológico , Animais , Modelos Animais de Doenças , Pulmão/irrigação sanguínea , Masculino , Monocrotalina/farmacologia , Oxirredução/efeitos dos fármacos , Hipertensão Arterial Pulmonar/fisiopatologia , Artéria Pulmonar/efeitos dos fármacos , Ratos , Ratos Wistar
8.
Steroids ; 132: 33-39, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29408449

RESUMO

Sida tuberculata (ST) is a Malvaceae species widely distributed in Southern Brazil. In traditional medicine, ST has been employed as hypoglycemic, hypocholesterolemic, anti-inflammatory and antimicrobial. Additionally, this species is chemically characterized by flavonoids, alkaloids and phytoecdysteroids mainly. The present work aimed to optimize the extractive technique and to validate an UHPLC method for the determination of 20-hydroxyecdsone (20HE) in the ST leaves. Box-Behnken Design (BBD) was used in method optimization. The extractive methods tested were: static and dynamic maceration, ultrasound, ultra-turrax and reflux. In the Box-Behnken three parameters were evaluated in three levels (-1, 0, +1), particle size, time and plant:solvent ratio. In validation method, the parameters of selectivity, specificity, linearity, limits of detection and quantification (LOD, LOQ), precision, accuracy and robustness were evaluated. The results indicate static maceration as better technique to obtain 20HE peak area in ST extract. The optimal extraction from surface response methodology was achieved with the parameters granulometry of 710 nm, 9 days of maceration and plant:solvent ratio 1:54 (w/v). The UHPLC-PDA analytical developed method showed full viability of performance, proving to be selective, linear, precise, accurate and robust for 20HE detection in ST leaves. The average content of 20HE was 0.56% per dry extract. Thus, the optimization of extractive method in ST leaves increased the concentration of 20HE in crude extract, and a reliable method was successfully developed according to validation requirements and in agreement with current legislation.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Ecdisterona/análise , Ecdisterona/isolamento & purificação , Malvaceae/química , Folhas de Planta/química , Ecdisterona/química , Limite de Detecção , Modelos Lineares , Reprodutibilidade dos Testes
9.
J Chromatogr A ; 1463: 60-70, 2016 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-27473512

RESUMO

Extraction methods evaluation to access plants metabolome is usually performed visually, lacking a truthful method of data handling. In the present study the major aim was developing reliable time- and solvent-saving extraction and fractionation methods to access alkaloid profiling of Psychotria nemorosa leaves. Ultrasound assisted extraction was selected as extraction method. Determined from a Fractional Factorial Design (FFD) approach, yield, sum of peak areas, and peak numbers were rather meaningless responses. However, Euclidean distance calculations between the UPLC-DAD metabolic profiles and the blank injection evidenced the extracts are highly diverse. Coupled with the calculation and plotting of effects per time point, it was possible to indicate thermolabile peaks. After screening, time and temperature were selected for optimization, while plant:solvent ratio was set at 1:50 (m/v), number of extractions at one and particle size at ≤180µm. From Central Composite Design (CCD) results modeling heights of important peaks, previously indicated by the FFD metabolic profile analysis, time was set at 65min and temperature at 45°C, thus avoiding degradation. For the fractionation step, a solid phase extraction method was optimized by a Box-Behnken Design (BBD) approach using the sum of peak areas as response. Sample concentration was consequently set at 150mg/mL, % acetonitrile in dichloromethane at 40% as eluting solvent, and eluting volume at 30mL. Summarized, the Euclidean distance and the metabolite profiles provided significant responses for accessing P. nemorosa alkaloids, allowing developing reliable extraction and fractionation methods, avoiding degradation and decreasing the required time and solvent volume.


Assuntos
Fracionamento Químico/métodos , Alcaloides Indólicos/isolamento & purificação , Metaboloma , Metabolômica , Psychotria/química , Psychotria/metabolismo , Extração em Fase Sólida/métodos , Alcaloides Indólicos/metabolismo , Folhas de Planta/química , Folhas de Planta/metabolismo , Solventes/química , Temperatura , Fatores de Tempo , Ultrassom
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