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1.
Int J Biol Macromol ; 116: 1282-1295, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29751041

RESUMEN

Adsorption has been explored to minimize the pollution caused by dyes. This work relates the preparation of diethylenetriamine-modified cellulose (DetaCel) by reacting phthalic anhydride-modified cellulose (PhCel) with diethylenetriamine (Deta). Materials were characterized by Elemental Analysis and results showed a degree of incorporation of 5.55 ±â€¯0.02 mmol of nitrogen per gram of modified material. The main bands observed for DetaCel by Fourier-Transform Infrared Spectroscospy (FTIR) were attributed to CN deformation (1330 cm-1) and NH stretching of amide (3400 cm-1), while Solid State Nuclear Magnetic Resonance of 13C (13C{1H}CP-MAS NMR) showed a signal at 164.6 ppm characteristic of amide group. Crystallinity index (CrI) obtained by X-Ray Diffraction (XRD) was 74.99 (Cel), 58.64 (PhCel) and 46.12% (DetaCel). Adsorbent matrices were employed to remove methyl orange (MO) and eosin (EY) dyes in aqueous medium. Data obtained experimentally from kinetic study had a better fit to the pseudo-first order, thus the adsorption process occurs in monolayer, with MO adsorption capacity by Cel and DetaCel of 2.19 and 65.45 mg g-1, respectively. For EY adsorption by Cel and DetaCel was 1.30 and 56.69 mg g-1, respectively. These results suggest that DetaCel can be used as an alternative potential for removal dyes in aqueous solution.


Asunto(s)
Compuestos Azo/química , Celulosa/química , Eosina Amarillenta-(YS)/química , Purificación del Agua/métodos , Adsorción
2.
Curr Pharm Biotechnol ; 17(14): 1278-1284, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27774891

RESUMEN

BACKGROUND: Phytol (3,7,11,15-tetramethylhexadec-2-en-1-ol; PHY), the alcoholic diterpenoid is particularly interesting due to its diverse activities found in literature. This study evaluated in vitro and in vivo antioxidant capacity of PHY. METHODS: We conducted DPPH• (2,2-diphenyl-1-picrylhydrazyl) and ABTS•+ (2,2'-azino-bis(3- ethylbenzthiazoline-6-sulphonic acid)) radical scavenging tests as in vitro, while Saccharomyces cerevisiae test as in vivo. For in vitro tests, trolox and for in vivo test hydrogen peroxide (H2O2) were taken as standard and stressor, respectively. Additionally, we measured the superoxide dismutase (SOD), catalase (CAT), reduced glutathione (GSH), lipid peroxidation (LP) and nitrite (NO2 -) contents in mouse hippocampus taking 0.05% Tween 80 dissolved in 0.9% saline (0.25 ml) and ascorbic acid (250 mg/kg; AA) as vehicle and standard, respectively. PHY was administered at doses 25, 50 and 75 mg/kg. In the latter case, all the treatments were administered via intraperitoneal (i.p.) route. RESULTS: PHY at 7.2 µg/ml exhibited 59.89 ± 0.73% and 62.79 ± 1.99% scavenging capacity of DPPH• and ABTS•+, respectively. In S. cerevisiae strains, PHY showed prominent protective effects. Moreover, in Swiss mouse hippocampus; PHY reduced the LP and NO2 - contents, while increased in GSH, SOD and CAT activities. CONCLUSION: PHY exerted antioxidant potential in our current non- and preclinical test systems and can be a good candidate for the development of treatments of oxidative stress mediated diseases.


Asunto(s)
Antioxidantes/farmacología , Fitol/farmacología , Animales , Masculino , Ratones , Oxidación-Reducción , Saccharomyces cerevisiae/metabolismo
3.
Photochem Photobiol Sci ; 13(12): 1650-4, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25360993

RESUMEN

An ethanol extract and different partition fractions obtained from Lippia origanoides H.B.K. were assayed for light-mediated activity against strains of Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli). Identical assays were conducted with and without exposure to UV-A (400-315 nm) light to test for light enhanced activity. The ethanol extract and dichloromethane fraction showed light-mediated activity against the S. aureus strain, but not against the E. coli strain. The dichloromethane fraction was more active than the ethanol extract. Naringenin did not display light-mediated activity against the tested bacteria, indicating that the light-mediated antimicrobial activity of the dichloromethane fraction is not due to its major component. The results represent the first report of light-mediated antimicrobial activity of Lippia origanoides and show that its phytochemicals could be used as light-mediated antimicrobial agents.


Asunto(s)
Antibacterianos/química , Lippia/química , Fármacos Fotosensibilizantes/química , Extractos Vegetales/química , Rayos Ultravioleta , Escherichia coli/efectos de los fármacos , Escherichia coli/efectos de la radiación , Flavanonas/química , Cloruro de Metileno/química , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/efectos de la radiación
4.
Artículo en Inglés | MEDLINE | ID: mdl-25202336

RESUMEN

The present study primarily aims to identify the relative density and the fatty acids (methyl esters) content present in the standardized ethanol extract of leaves of M. glomerata (EPMG). Meanwhile, in a second moment, this study evaluated the effects of the EPMG on the levels of amino acids in the hippocampus, and the mechanism of sedative and anxiolytic action. Adult mice were treated with doses of 200, 300, and 400 mg/kg and evaluated in open field, elevated plus-maze, light dark, and rotarod tests. Moreover, in the behavioral tests diazepam (GABAergic anxiolytic, 2 mg/kg) as positive control and flumazenil (GABA antagonist, 2.5 mg/kg) were used to identify mechanism of sedative and anxiolytic action produced by EPMG. The EPMG is constituted by the following compounds: methyl cinnamate, 2H-1-benzopyran-2-one, (2-hydroxyphenyl)methyl propionate, (Z)-methyl-hexadec-7-enoate, methyl hexadecanoate, hexadecanoic acid, (Z)-methyl-octadec-9-enoate, octadecanoic acid, and squalene. This extract demonstrated anxiolytic effects, which may be mediated by GABAergic system, and was able to increase GABA levels and reduce of glutamate and aspartate concentrations in mice hippocampus, which can directly and/or indirectly assist in their anxiolytic effect. Although more studies are needed, the EPMG could represent an interesting therapeutical strategy in the treatment of anxiety.

5.
Nat Prod Res ; 28(5): 340-3, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24261482

RESUMEN

Propolis is a complex matrix of chemical constituents extracted from plants and produced by bees which is used in folk medicine due to its several pharmacological properties. Its chemical composition varies according to the region where it is produced. This work has studied the antileishmanial activity and cytotoxicity of brown propolis (BP) originating from the semi-arid region of Piauí, Brazil. The BP showed significant inhibition of the Leishmania amazonensis promastigotes growth as well as being effective in reducing infection of murine macrophages and the number of internalised amastigotes in these cells. The dichloromethane fraction was the most active and showed the best selectivity index. The studied samples presented good activity and the fractioning improved the antileishmanial activity without an increase in the cytotoxicity against mammalian cells. Therefore, BP is a potential source for development of apitherapeutic products for the treatment of leishmaniasis.


Asunto(s)
Antiprotozoarios/aislamiento & purificación , Antiprotozoarios/farmacología , Leishmania/efectos de los fármacos , Leishmaniasis/tratamiento farmacológico , Própolis/química , Própolis/farmacología , Animales , Antiprotozoarios/química , Brasil , Cromatografía de Gases y Espectrometría de Masas , Concentración 50 Inhibidora , Macrófagos Peritoneales/efectos de los fármacos
6.
Basic Clin Pharmacol Toxicol ; 112(1): 34-41, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22788872

RESUMEN

Platonia insignis Mart., a native species of the Brazilian Amazon more commonly known as bacuri, is a member of the Clusiaceae family. In this study, we evaluated the chemical composition and the antioxidant and toxicity activities of the dichloromethane and ethyl acetate fractions from P. insignis seed ethanolic extract using different experimental models. Our results demonstrate in vitro antioxidant effects, by 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) diammonium salt and 1,1-diphenyl-2-picryl-hydrazyl assays, as well as in vivo effects in antioxidant-defective Saccharomyces cerevisiae strains to both fractions. Toxicity was evaluated against the micro-crustaceous Artemia salina Leach. and promastigote Leishmania amazonensis. The dichloromethane fraction was the most active fraction evaluated on A. salina and promastigote L. amazonensis (IC(50)  = 24.89 µg/mL and 2.84 µg/mL, respectively). In addition, a slight cytotoxicity was observed in mammalian V79 cells using ethyl acetate and dichloromethane fractions with MTT assays. Both fractions displayed genotoxicity up to 25 µg/mL (dichloromethane) and 10 µg/mL (ethyl acetate) in V79 cells, as evaluated by the alkaline comet assay. Thus, in this study, we demonstrate for the first time that ethyl acetate and dichloromethane fractions from P. insignis seeds display antioxidant effects, a toxic effect against A. salina and L. amazonensis and induce genotoxicity in V79 mammalian cells. The observed activities can be attributed to the phenolic compounds present in these fractions and to the presence of xanthones (alpha- and gamma-mangostin).


Asunto(s)
Clusiaceae , Extractos Vegetales/farmacología , Acetatos , Animales , Antioxidantes/farmacología , Artemia/efectos de los fármacos , Clusiaceae/química , Cricetinae , Cricetulus , Leishmania/efectos de los fármacos , Cloruro de Metileno , Fenoles/análisis , Semillas
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