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1.
Anal Methods ; 15(29): 3499-3509, 2023 07 27.
Artículo en Inglés | MEDLINE | ID: mdl-37401176

RESUMEN

Considering the great economic significance of Coffea arabica (arabica) associated with the lower production cost of C. canephora (conilon), blends of these coffees are commercially available to reduce costs and combine sensory attributes. Thus, analytical tools are required to ensure consistency between real and labeled compositions. In this sense, chromatographic methods based on volatile analysis using static headspace-gas chromatography-mass spectrometry (SHS-GC-MS) and Fourier transform infrared (FTIR) spectroscopy associated with chemometric tools were proposed for the identification and quantification of arabica and conilon blends. The peak integration from the total ion chromatogram (TIC) and extracted ion chromatogram (EIC) was compared in multivariate and univariate scenarios. The optimized partial least squares (PLS) models with uninformative variable elimination (UVE) and chromatographic data (TIC and EIC) have similar accuracy according to a randomized test, with prediction errors between 3.3% and 4.7% and Rp2 > 0.98. There was no difference between the univariate models for the TIC and EIC, but the FTIR model presented a lower performance than GC-MS. The multivariate and univariate models based on chromatographic data had similar accuracy. For the classification models, the FTIR, TIC, and EIC data presented accuracies from 96% to 100% and error rates from 0% to 5%. Multivariate and univariate analyses combined with chromatographic and spectroscopic data allow the investigation of coffee blends.


Asunto(s)
Coffea , Coffea/química , Cromatografía de Gases y Espectrometría de Masas , Café/química , Análisis de los Mínimos Cuadrados , Espectroscopía Infrarroja por Transformada de Fourier
2.
Talanta ; 205: 120100, 2019 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-31450412

RESUMEN

An extraction method based on a multivariate analytical approach was developed for enhancement of the phenolic compounds in cashew nut extracts. The different extractor solvents (acetone, water, ethanol, and methanol) and their binary, ternary, and quaternary combinations were evaluated using a simplex-centroid design and surface response methodology. The special cubic model exhibits no lack of fit and explains 89.2% of the variance. The total phenolic measurements by the Folin-Ciocalteu method revealed the highest values for ethanol (5.93 mg GAE g-1) and acetone-methanol-ethanol ternary mixture (5.92 mg GAE g-1) extracts. ESI (-)-Q/TOFMS analyses combined with PCA and HCA revealed the presence of fatty acids, phospholipids, and sugars in the ternary mixture cashew extract, while for the ethanol extract only phenolic compounds, such as anacardic acids and derivatives, were found. The proposed approach was adequate to reach the optimal extractor which ethanol, a low-toxicity solvent, enabled the selective extraction of a high content of phenolic compounds from cashew nuts.


Asunto(s)
Ácidos Anacárdicos/análisis , Anacardium/química , Nueces/química , Extracción en Fase Sólida/métodos , Acetona/química , Ácidos Anacárdicos/aislamiento & purificación , Análisis por Conglomerados , Etanol/química , Metanol/química , Análisis Multivariante , Análisis de Componente Principal , Solventes/química , Espectrometría de Masa por Ionización de Electrospray/métodos
3.
Molecules ; 20(3): 4204-24, 2015 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-25751783

RESUMEN

Mimosa caesalpiniifolia is a native plant of the Brazilian northeast, and few studies have investigated its chemical composition and biological significance. This work describes the identification of the first chemical constituents in the ethanolic extract and fractions of M. caesalpiniifolia stem bark based on NMR, GC-qMS and HRMS analyses, as well as an assessment of their cytotoxic activity. GC-qMS analysis showed fatty acid derivatives, triterpenes and steroid substances and confirmed the identity of the chemical compounds isolated from the hexane fraction. Metabolite biodiversity in M. caesalpiniifolia stem bark revealed the differentiated accumulation of pentacyclic triterpenic acids, with a high content of betulinic acid and minor amounts of 3-oxo and 3ß-acetoxy derivatives. Bioactive analysis based on total phenolic and flavonoid content showed a high amount of these compounds in the ethanolic extract, and ESI-(-)-LTQ-Orbitrap-MS identified caffeoyl hexose at high intensity, as well as the presence of phenolic acids and flavonoids. Furthermore, the evaluation of the ethanolic extract and fractions, including betulinic acid, against colon (HCT-116), ovarian (OVCAR-8) and glioblastoma (SF-295) tumour cell lines showed that the crude extract, hexane and dichloromethane fractions possessed moderate to high inhibitory activity, which may be related to the abundance of betulinic acid. The phytochemical and biological study of M. caesalpiniifolia stem bark thus revealed a new alternative source of antitumour compounds, possibly made effective by the presence of betulinic acid and by chemical co-synergism with other compounds.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Supervivencia Celular/efectos de los fármacos , Flavonoides/farmacología , Mimosa/química , Neoplasias/tratamiento farmacológico , Corteza de la Planta/química , Extractos Vegetales/química , Antineoplásicos Fitogénicos/aislamiento & purificación , Flavonoides/aislamiento & purificación , Humanos , Neoplasias/patología , Triterpenos Pentacíclicos , Fenoles/aislamiento & purificación , Fenoles/farmacología , Triterpenos/farmacología , Células Tumorales Cultivadas , Ácido Betulínico
4.
Pharmacogn Mag ; 10(Suppl 3): S456-62, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25298660

RESUMEN

BACKGROUND: Mimosa caesalpiniifolia Benth. (Leguminosae) is widely found in the Brazilian Northeast region and markedly contributes to production of pollen and honey, being considered an important honey plant in this region. OBJECTIVE: To investigate the chemical composition of the ethanol extract of leaves from M. caesalpiniifolia by GC-MS after derivatization (silylation), as well as to evaluate the in vitro and in vivo toxicological effects and androgenic activity in rats. MATERIALS AND METHODS: The ethanol extract of leaves from Mimosa caesalpiniifolia was submitted to derivatization by silylation and analyzed by gas chromatography-mass spectrometry (GC-MS) to identification of chemical constituents. In vitro toxicological evaluation was performed by MTT assay in murine macrophages and by Artemia salina lethality assay, and the in vivo acute oral toxicity and androgenic evaluation in rats. RESULTS: Totally, 32 components were detected: Phytol-TMS (11.66%), lactic acid-2TMS (9.16%), α-tocopherol-TMS (7.34%) and ß-sitosterol-TMS (6.80%) were the major constituents. At the concentrations analyzed, the ethanol extract showed low cytotoxicity against brine shrimp (Artemia salina) and murine macrophages. In addition, the extract did not exhibit any toxicological effect or androgenic activity in rats. CONCLUSIONS: The derivatization by silylation allowed a rapid identification of chemical compounds from the M. caesalpiniifolia leaves extract. Besides, this species presents a good safety profile as observed in toxicological studies, and possess a great potential in the production of herbal medicines or as for food consumption.

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