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1.
Chem Cent J ; 12(1): 37, 2018 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-29619619

RESUMO

BACKGROUND: In the present study, tara seed oil was obtained by supercritical fluid extraction and used to investigate the antioxidant strength of carnosic acid (CA) compared with conventional synthetic antioxidants. METHODS: The antioxidants were added to the tara seed oil at 0.2 mg of antioxidant per gram of oil. The samples were then submitted to at 60 °C 15 days for an accelerated oxidation process, with samples taken regularly for analysis. After oxidation, the samples were analyzed to determine the peroxide value, thiobarbituric acid reactive substances, conjugated diene content, and free fatty acid content. CA was investigated at three purity levels (CA20, CA60, CA99), and compared with three synthetic antioxidants (butylatedhydroxyanisole, butylatedhydroxytoluene, and tert-butylhydroquinone). RESULTS: The oxidation indicators showed that CA was a strong antioxidant compared to the synthetic antioxidants. The antioxidant activities decreased in the order: tert-butylhydroquinone > CA99 > CA60 > CA20 > butylatedhydroxyanisole > butylatedhydroxytoluene. These results show that CA could be used to replace synthetic antioxidants in oil products, and should be safer for human consumption and the environment.

2.
Biol Pharm Bull ; 37(12): 1994-7, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25590090

RESUMO

The skeletal renin­angiotensin system (RAS) is involved in the progression of osteoporosis and the active peptide within the RAS, angiotensin II (ANG II), has deleterious effects on bones. This study was performed to investigate whether suppression of the rate-limiting step of the RAS cascade by the renin inhibitor aliskiren has a benefit on trabecular bone in osteoporotic mice. A postmenopausal osteoporosis model was induced by bilateral ovariectomy. The ovariectomized (OVX) mice were treated with a low (5 mg/kg) or high (25 mg/kg) dose of aliskiren for 6 weeks. Micro-computed tomography was performed to detect trabecular bone parameters of lumbar vertebra and to obtain 3-dimensional (3D) images. Treatment with aliskiren markedly increased bone volume over total volume (p<0.05), trabecular bone number (p<0.05), connectivity density (p<0.05), and bone mineral density (p<0.05) and reduced trabecular bone separation (p<0.05) compared to vehicle-treated OVX mice. Similarly, the 3D images were consistent with the quantitative data that showed aliskiren could markedly reverse the ovariectomy-induced pathological changes of trabecular bone. Thus, this study indicated that the treatment of estrogen-deficient mice with aliskiren could markedly increase bone mass and improve trabecular bone structure, suggesting its potential application in treating postmenopausal osteoporosis.


Assuntos
Amidas/uso terapêutico , Fumaratos/uso terapêutico , Vértebras Lombares/patologia , Osteoporose/tratamento farmacológico , Ovariectomia/efeitos adversos , Renina/antagonistas & inibidores , Animais , Anti-Hipertensivos/uso terapêutico , Feminino , Vértebras Lombares/efeitos dos fármacos , Camundongos , Osteoporose/etiologia , Sistema Renina-Angiotensina/fisiologia , Microtomografia por Raio-X
3.
Food Chem ; 138(1): 173-9, 2013 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-23265473

RESUMO

An ionic liquid-based ultrasonic-assisted extraction (ILUAE) method had been used for the effective extraction of isoliquiritigenin (IQ), liquiritin (LQ) and glycyrrhizic acid (GA) from licorice. The ionic liquids with different cations and anions were investigated in this work and 0.5 M 1-butyl-3-methylimidazolium bromide solution was selected as solvent. In addition, the technical parameters including soaking time, solid-liquid ratio, ultrasonic power and time were optimized. Compared with the conventional solvent extraction, the proposed approach exhibited higher efficiency, which indicated the ILUAE was an efficient, rapid and simple sample preparation technique. There was no degradation of the target analytes had been observed at the optimum conditions which was evidenced by the stability studies performed with standard of IQ, LQ and GA. The proposed method also showed high reproducibility and was environmental friendly.


Assuntos
Chalconas/isolamento & purificação , Fracionamento Químico/métodos , Flavanonas/isolamento & purificação , Glucosídeos/isolamento & purificação , Glycyrrhiza/química , Ácido Glicirrízico/isolamento & purificação , Extratos Vegetais/isolamento & purificação , Ultrassom/métodos , Chalconas/análise , Cromatografia Líquida de Alta Pressão , Flavanonas/análise , Glucosídeos/análise , Ácido Glicirrízico/análise , Líquidos Iônicos/química , Extratos Vegetais/análise
4.
Molecules ; 17(3): 3510-23, 2012 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-22430118

RESUMO

In present study, the performance and separation characteristics of 21 macroporous resins for the enrichment and purification of deoxyschizandrin and γ-schizandrin, the two major lignans from Schisandra chinensis extracts, were evaluated. According to our results, HPD5000, which adsorbs by the molecular tiers model, was the best macroporous resin, offering higher adsorption and desorption capacities and higher adsorption speed for deoxyschizandrin and γ-schizandrin than other resins. Columns packed with HPD5000 resin were used to perform dynamic adsorption and desorption tests to optimize the technical parameters of the separation process. The results showed that the best adsorption time is 4 h, the rate of adsorption is 0.85 mL/min (4 BV/h) and the rate of desorption is 0.43 mL/min (2 BV/h). After elution with 90% ethanol, the purity of deoxy-schizandrin increased 12.62-fold from 0.37% to 4.67%, the purity of γ-schizandrin increased 15.8-fold from 0.65% to 10.27%, and the recovery rate was more than 80%.


Assuntos
Ciclo-Octanos/isolamento & purificação , Frutas/química , Lignanas/isolamento & purificação , Compostos Policíclicos/isolamento & purificação , Resinas Sintéticas/química , Schisandra/química , Adsorção , Ciclo-Octanos/química , Lignanas/química , Compostos Policíclicos/química
5.
J Chromatogr B Analyt Technol Biomed Life Sci ; 879(30): 3444-51, 2011 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-21963273

RESUMO

In this study, ester-bond biphenyl cyclooctene lignans were efficiently hydrolytically degraded into free biphenyl cyclooctene lignans by ion exchange resin transformation and simultaneous removal of impurities by macroporous resin. The OH-type strongly basic anion exchange resin 201×7 was the best one, and the dynamic hydrolysis efficiency was 146.7±5.0%. HPD5000 macroporous resin, which offered higher adsorption and desorption capacities and faster adsorption than other resins. The purity of free biphenyl cyclooctene lignans in the product increased from 5.14±0.24% to 79.67±0.0.67%. After dynamic catalytic transformation by 201×7 resin combined with purification of HPD5000 resin, the yield and the purity of free biphenyl cyclooctene lignans in the product were 132.1±4.7% and 80.91±3.53%, respectively.


Assuntos
Cromatografia por Troca Iônica/métodos , Ciclo-Octanos/isolamento & purificação , Dioxóis/isolamento & purificação , Lignanas/isolamento & purificação , Compostos Policíclicos/isolamento & purificação , Schisandra/química , Adsorção , Análise de Variância , Etanol , Frutas/química , Hidrólise , Resinas de Troca Iônica , Extratos Vegetais/química , Espectrometria de Massas por Ionização por Electrospray , Temperatura
6.
Ying Yong Sheng Tai Xue Bao ; 19(4): 911-4, 2008 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-18593057

RESUMO

The quantitative changes of anti-cancer ingredients such as taxol, cephalomannine, baccatin III and 10-deacetylbaccatin III in the branches and leaves of Taxus chinensis var. mairei during one growth season were measured by HPLC. The results showed that the contents of these anticancer ingredients had an obvious change from April when the new branches began to germinate to November when the branches basically stopped growing. The contents of taxol and cephalomannine in the branches and leaves of T. chinensis had the same change pattern, with the peaks appeared in May, and those of Baccatin III and 10-deacetylbaccatin III had the same change trend, with the highest values appeared in September and April, respectively. There was a significant positive correlation between the contents of taxol and cephalomannine (P <0.05), and a negative correlation between the contents of cephalomannine and 10-deacetylbaccatin III (P <0.05).


Assuntos
Antineoplásicos Fitogênicos/análise , Folhas de Planta/química , Estações do Ano , Taxus/química , Alcaloides/análise , Cromatografia Líquida de Alta Pressão , Paclitaxel/análise , Folhas de Planta/crescimento & desenvolvimento , Taxoides/análise , Taxus/crescimento & desenvolvimento
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