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1.
Nat Prod Res ; 37(5): 776-781, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35648109

RESUMEN

This study evaluated the analgesic and anti-inflammatory activities of Vitex polygama. Ethyl acetate and butanol fractions (10-30 mg/kg), obtained from the hydroalcoholic leaf extract, showed an antinociceptive effect in the acetic acid-induced abdominal writhing test, formalin test and modified hot plate test in mice, indicating a peripheral anti-inflammatory action. Ethyl acetate and butanol fractions were effective in inhibiting nitric oxide and TNF-α production, respectively, in RAW 264.7 macrophages. Both fractions (10-30 mg/kg) showed an acute analgesic effect in mice with vincristine-induced neuropathic pain exposed to a thermal stimulus. Through ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-UV-MS/MS) it was possible to identify seven major compounds: isoorientin, orientin, vitexin, isovitexin, O-p-hydroxybenzoyl orientin, O-caffeoyl-orientin, and di-caffeoylquinic acid. Orientin and isoorientin were isolated from ethyl acetate fraction and had their identity confirmed by nuclear magnetic resonance (NMR). Glucosyl flavones appear to be the main metabolites responsible for the anti-inflammatory and analgesic activities observed for V. polygama.


Asunto(s)
Vitex , Ratones , Animales , Espectrometría de Masas en Tándem , Butanoles , Extractos Vegetales/farmacología , Extractos Vegetales/química , Analgésicos/farmacología , Analgésicos/química , Antiinflamatorios/farmacología , Antiinflamatorios/química , Acetatos
2.
Nat Prod Res ; 36(5): 1337-1341, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33380215

RESUMEN

Tuberculosis (TB) remains a worldwide public health threat because of the emergence of resistant strains and subsequent inappropriate response to current therapy. We have been studying the restinga plants' antimycobacterial and anti-inflammatory potential. Dichloromethane fraction (DCM) from Vitex polygama Cham. showed high activity against Mycobacterium tuberculosis (Mtb) H37Rv. In this context, DCM fraction and isolated compounds were investigated against Mtb H37Rv and M299 (MDR strain) and for their immunomodulatory and cytotoxicity actions. Orientin showed the best antimycobacterial effect against Mtb M299 MDR strain (MIC50 15.4 ± 1.6 µg/mL), capacity of inhibiting NO production by macrophages (IC50 6.5 ± 1.2 µg/mL) and no significant cytotoxicity. The antimycobacterial effect of orientin was also observed on Mtb H37Rv intracellular growth in RAW 264.7 macrophages (MIC50 3.5 ± 1.1 and MIC90 9.1 ± 1.0 µg/mL). This is the first report describing the antimycobacterial effect of orientin, in both extra- and intracellular growth.[Formula: see text].


Asunto(s)
Productos Biológicos , Mycobacterium tuberculosis , Vitex , Antiinflamatorios/farmacología , Antituberculosos/farmacología , Productos Biológicos/farmacología , Pruebas de Sensibilidad Microbiana
3.
Planta Med ; 81(17): 1609-13, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26132850

RESUMEN

Verbascoside is a phenylethanoid glycoside widely distributed in nature, especially among the order Lamiales, occurring in numerous plants that are constituents of folk medicine preparations. This natural compound, previously isolated by our group from the ethyl acetate extract of Lantana trifolia using the gradient approach in countercurrent chromatography, was now isolated from the butanol extract of the same plant and from Lippia alba f. intermedia (Verbenaceae) using countercurrent chromatography in either gradient or isocratic elution modes. The ethyl acetate extract of L. alba, rich in phenylethanoids and flavonoids, was fractionated using countercurrent chromatography in the step-gradient elution approach. The four-step solvent system was composed of n-hexane-ethyl acetate-n-butanol-water (4 : 10 : X : 10), where X = 1 (solvent system A), 3 (solvent system B), 5 (solvent system C), and 7 (solvent system D), and allowed for the isolation of verbascoside along with other phenylethanoids and flavonoids from both plants. Verbascoside and 2'-O-ß-apiosylverbascoside were further isolated from the n-butanol extract of L. trifolia using the solvent system ethyl acetate-n-butanol-water 10 : 2 : 10 on an isocratic run. The difference in the complexity of the two plant extracts demanded different purification steps, which included a second high-speed countercurrent chromatography purification using the isocratic elution mode.


Asunto(s)
Distribución en Contracorriente , Glucósidos/aislamiento & purificación , Lantana/química , Lippia/química , Fenoles/aislamiento & purificación , Extractos Vegetales/aislamiento & purificación , 1-Butanol , Acetatos , Brasil , Flavonoides/aislamiento & purificación , Estructura Molecular , Solventes
4.
J Chromatogr A ; 1319: 166-71, 2013 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-24192149

RESUMEN

Species of Aspidosperma (Apocynaceae) are characterized by the occurrence of indole alkaloids, but few recent reports on Aspidosperma rigidum Rusby chemical constituents were found. The present work shows the application of pH-zone refining countercurrent chromatography on the separation of alkaloids from the barks of A. rigidum. In this study, the dichloromethane extract was fractionated with the solvent system composed of methyl-tert-butyl ether and water with different concentrations of the retainer triethylamine in the organic stationary phase and formic or hydrochloric acids as eluters in the aqueous mobile phase, in order to evaluate the most suitable condition. In each experiment, from circa 200mg of the dichloromethane extract of A. rigidum, three major alkaloids were isolated and identified as 3α-aricine (circa 17mg), isoreserpiline (ca. 22mg) and 3ß-reserpiline (ca. 40mg), with relative purity of 79%, 89% and 82% respectively, in a one-step separation of 2h. Two of them - 3α-aricine and isoreserpiline - were isolated and identified for the first time in this species.


Asunto(s)
Aspidosperma/química , Distribución en Contracorriente/métodos , Concentración de Iones de Hidrógeno , Alcaloides Indólicos/aislamiento & purificación , Cromatografía Líquida de Alta Presión , Cloruro de Metileno/química
5.
J Sep Sci ; 34(9): 971-7, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-21442750

RESUMEN

In this work we report the purification of a crude acetin mixture into mono-, di- and triacetin by countercurrent chromatography. The process was initially tested on a small, semi-preparative scale (0.5 g) to determine its efficiency. The process was then scaled up to accommodate 2.5 g of crude reaction products containing a mixture of the acetins. The solvent system ethyl acetate/n-butanol/water 1:0.2:1 was used in all separation procedures. Mono-, di- and triacetins were separated similarly in the semi-preparative and preparative runs.


Asunto(s)
Distribución en Contracorriente/métodos , Glicéridos/aislamiento & purificación , Acetatos/química , Biocombustibles , Glicéridos/síntesis química , Glicerol/química
6.
Nat Prod Commun ; 4(12): 1675-8, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20120105

RESUMEN

The essential oil from Anemia tomentosa var. anthriscifolia showed in vitro activity against Mycobacterium tuberculosis (MIC 100 microg/ml) and therefore was characterized by gas chromatography (GC) and by gas chromatography coupled with mass spectrometry (GC-MS). The major constituents of this essential oil were triquinane sesquiterpenes: silphiperfol-6-ene (14.7%), (-)-epi-presilphiperfolan-1-ol (30.6%), presilphiperfol-7-ene (3.9%), cameroonan-7 alpha-ol (4.4%), prenopsan-8-ol (1.9%) and presilphiperfolan-8-ol (8.3%), suggesting the existence of different chemotypes for this species. The essential oil was fractionated by column chromatography and its major constituent and fractions were assayed against Mycobacterium tuberculosis and M. smegmatis. (-)-epi-Presilphiperfolan-1-ol exhibited an MIC of 120 microg/ml against M. tuberculosis H37Rv.


Asunto(s)
Antituberculosos/química , Antituberculosos/farmacología , Mycobacterium tuberculosis/efectos de los fármacos , Aceites Volátiles/química , Aceites Volátiles/farmacología , Plantas Medicinales/química , Brasil , Cromatografía de Gases y Espectrometría de Masas , Lípidos/química , Espectrometría de Masas , Pruebas de Sensibilidad Microbiana
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