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1.
Small ; 20(25): e2310227, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38196154

RESUMO

Perovskite solar cells (PSCs) have achieved revolutionary progress during the past decades with a rapidly boosting rate in power conversion efficiencies from 3.8% to 26.1%. However, high-efficiency PSCs with organic hole-transporting materials (HTMs) suffer from inferior long-term stability and high costs. The replacement of organic HTMs with inorganic counterparts such as metal oxides can solve the above-mentioned problems to realize highly robust and cost-effective PSCs. Nevertheless, the widely used simple metal oxide-based HTMs are limited by the low conductivity and poor light transmittance due to the fixed atomic environment. As an emerging family of inorganic HTMs, complex metal oxides with superior structural/compositional flexibility have attracted rapidly increasing interest recently, showing superior carrier conductivity/mobility and superb light transmittance. Herein, the recent advancements in the design and development of complex metal oxide-based HTMs for high-performance PSCs are summarized by emphasizing the superiority of complex metal oxides as HTMs over simple metal oxide-based counterparts. Consequently, several distinct strategies for the design of complex metal oxide-based HTMs are proposed. Last, the future directions and remaining challenges of inorganic complex metal oxide-based HTMs for PSCs are also presented. This review aims to provide valuable guidelines for the further advancements of robust, high-efficiency, and low-cost PSCs.

2.
Nanoscale ; 15(9): 4344-4352, 2023 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-36757208

RESUMO

Halide perovskite solar cells (PSCs) have received remarkably increasing interests due to their facile fabrication procedures, use of cost-effective raw materials, and high power conversion efficiencies (PCEs) during the past 10 years. Nevertheless, the state-of-the-art organic-inorganic PSCs suffer from high defect concentration and inferior humid/thermal stability, significantly restricting the widespread applications of PSCs. More specifically, point defects including metallic lead (Pb0) and halide iodine (I0) are easily generated in Pb/I-based PSCs during fabrication processes and operational conditions due to the inferior interaction between the anions and cations in halide perovskites and promote detrimental carrier recombination and ion migration, leading to inferior PCEs and durability of the PSCs. Herein, to tackle the above-mentioned issues, iodide/triiodide (I-/I3-) redox shuttles as a new additive were introduced to simultaneously passivate the cation and anion defects of methylammonium lead iodide (MAPbI3)-based PSCs. In particular, I-/I3- redox shuttles play a vital role in regenerating the cation (Pb0) and anion (I0) defects through the redox cycles of Pb0/Pb2+ and I0/I-. Consequently, the cell with an optimized amount of I-/I3- additive generated a superior PCE of 20.4%, which was 12% higher than the pristine device (18.2%). Furthermore, the introduction of the I-/I3- additive remarkably improved the humid and thermal stability of MAPbI3-based PSCs. This work manifests the importance of the design of redox shuttle-based additives to boost the efficiency and durability of organic-inorganic PSCs.

3.
Food Funct ; 7(3): 1492-500, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26882870

RESUMO

Chaenomeles thibetica, a type of fruit of the genus Chaenomeles, is commonly cultivated and used as Mugua in China and as liquor, candy, and functional food in Tibet. Total phenol, flavonoid, and proanthocyanidin contents were measured in C. thibetica extract (CTE). CTE had a positive effect on free radical scavenging and anti-lipid oxidation in vitro. The protective effects of CTE against carbon tetrachloride (CCl4)-induced oxidative damage in vivo were also measured. The results of antioxidative enzymes indicated that CTE can increase the activities of the catalase, superoxide dismutase, and glutathione contents and reduce the level of malondialdehyde in rats. The levels of alanine aminotransferase, aspartate transaminase, alkaline phosphatase, and total bilirubin were significantly reversed by CTE compared with the elevated levels in the CCl4 group. Besides, CTE could reverse the cell viability of HepG2 inoculated with CCl4via phosphorylation of mitogen-activated protein kinases (MAPKs), activating the nuclear factor (erythroid-derived 2)-like 2 (Nrf2) and increasing the expression of phase II detoxification enzymes. These effects may expand the applications of C. thibetica and offer alternative food with antioxidant and hepatoprotective functions in the food industry.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas/prevenção & controle , Fígado/efeitos dos fármacos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Extratos Vegetais/administração & dosagem , Substâncias Protetoras/administração & dosagem , Rosaceae/química , Alanina Transaminase/metabolismo , Animais , Aspartato Aminotransferases/metabolismo , Tetracloreto de Carbono/efeitos adversos , Doença Hepática Induzida por Substâncias e Drogas/enzimologia , Doença Hepática Induzida por Substâncias e Drogas/genética , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Feminino , Humanos , Fígado/enzimologia , Masculino , Proteínas Quinases Ativadas por Mitógeno/genética , Fator 2 Relacionado a NF-E2/genética , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos , Tibet
4.
J Agric Food Chem ; 63(50): 10791-802, 2015 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-26586022

RESUMO

Chicory has a major geographical presence in Europe and Asia. Cichorium glandulosum Boiss. et Huet, a genus Cichorium, is used for medicinal and food purposes in Asia. In this study, a dicaffeoylquinic acid-enriched fraction of C. glandulosum seeds n-BuOH fraction (CGSB) could ameliorate type 1 diabetes mellitus (T1DM) in streptozotocin (STZ)-induced diabetic mice with continuous administration for 2 weeks. CGSB treatment showed significantly higher plasma insulin levels but lower free fatty acids in adipose tissue and liver. Moreover, CGSB improved pancreatic islet mass. In vitro, different fractions of C. glandulosum seed (CGS) induced the differentiation of 3T3-L1 preadipocytes. The mRNA level for peroxisome proliferator-activated receptor alpha increased in high glucose treatment group in HepG2 cells, while CGSB significantly down-regulated the mRNA expression. The main compound of CGSB, 3,5-dicaffeoylquinic acid, was isolated and identified, which exhibited α-glucosidase inhibitory activity. These findings demonstrated that CGSB attenuated experimental T1DM via multipathway protection.


Assuntos
Cichorium intybus/química , Diabetes Mellitus Experimental/prevenção & controle , Diabetes Mellitus Tipo 1/prevenção & controle , Extratos Vegetais/administração & dosagem , Ácido Quínico/análogos & derivados , Sementes/química , Células 3T3-L1 , Tecido Adiposo/química , Animais , Diferenciação Celular/efeitos dos fármacos , Diabetes Mellitus Experimental/metabolismo , Ácidos Graxos não Esterificados/análise , Regulação da Expressão Gênica/efeitos dos fármacos , Inibidores de Glicosídeo Hidrolases , Células Hep G2 , Humanos , Hipoglicemiantes , Insulina/sangue , Fígado/química , Masculino , Camundongos , PPAR alfa/genética , Ácido Quínico/administração & dosagem , Ácido Quínico/análise , Ácido Quínico/metabolismo , RNA Mensageiro/análise , alfa-Glucosidases
5.
PLoS One ; 10(7): e0131733, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26133771

RESUMO

This study aimed to evaluate the inhibitory effects of dill (Anethum graveolens L.) seed essential oil against Sclerotinia sclerotiorum and its mechanism of action. The antifungal activities of the two main constituents, namely carvone and limonene, were also measured. Mycelial growth and sclerotial germination were thoroughly inhibited by dill seed essential oil at the 1.00 µL/mL under contact condition and 0.125µL/mL air under vapor condition. Carvone also contributed more than limonene in inhibiting the growth of S. sclerotiorum. Carvone and limonene synergistically inhibited the growth of the fungus. In vivo experiments, the essential oil remarkably suppressed S. sclerotiorum, and considerable morphological alterations were observed in the hyphae and sclerotia. Inhibition of ergosterol synthesis, malate dehydrogenase, succinate dehydrogenase activities, and external medium acidification were investigated to elucidate the antifungal mechanism of the essential oil. The seed essential oil of A. graveolens can be extensively used in agriculture for preventing the oilseed crops fungal disease.


Assuntos
Anethum graveolens/química , Brassica rapa/microbiologia , Cicloexenos/química , Monoterpenos/química , Óleos Voláteis/química , Doenças das Plantas/prevenção & controle , Terpenos/química , Antifúngicos/química , Ascomicetos/patogenicidade , Brassica rapa/metabolismo , Cromatografia Gasosa , Monoterpenos Cicloexânicos , Ergosterol/química , Germinação/efeitos dos fármacos , Hifas/efeitos dos fármacos , Limoneno , Malato Desidrogenase/metabolismo , Espectrometria de Massas , Mitocôndrias/metabolismo , Doenças das Plantas/terapia , Óleos de Plantas/química , Sementes/química , Succinato Desidrogenase/metabolismo
6.
Food Funct ; 5(5): 869-75, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24595542

RESUMO

Cichorium glandulosum Boiss. et Huet, a common herb for treating hepatitis, is indigenous to Europe, Western Asia, and the Xinjiang Uygur Autonomous Region of China. This study aims at evaluating the protective activity of different extracts from C. glandulosum seeds against experimental oxidation- and ultraviolet B (UVB)-induced damage in rat liver mitochondria. The antioxidant property of different extracts from C. glandulosum seeds was investigated by employing various established in vitro systems, such as α,α-diphenyl-ß-picrylhydrazyl, 2,2'-azinobis(3-ethylbenzthiazoline-6-sulphonic acid), and reducing power assay. The protective effects of different C. glandulosum seed extracts against UVB-induced phototoxicity in a mitochondria model were also evaluated by measuring thiobarbituric acid reactive substances, glutathione, lipid hydroperoxide, conjugated diene, and 4-hydroxynonenal. The main compounds in C. glandulosum seeds were identified by HPLC-PDA-ESI-MS/MS. The results showed that C. glandulosum seed extracts have strong antioxidant activity, in which the ethyl acetate extract (EE) and n-butanol extract (BE) showed better activity than other extracts. In a UVB-induced mitochondria model, both EE and BE have better antioxidant activity and protective effects against phototoxicity than the petroleum ether extract, chloroform extract, and water extract. The differences in antioxidant activity and photoprotective capacity among these five extracts are associated with their phenolic compound content. Therefore, research on this function of C. glandulosum seeds may broaden their applications in the food and medical industry.


Assuntos
Asteraceae/química , Medicamentos de Ervas Chinesas/administração & dosagem , Hepatopatias/prevenção & controle , Mitocôndrias Hepáticas/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Substâncias Protetoras/administração & dosagem , Sementes/química , Raios Ultravioleta/efeitos adversos , Animais , Antioxidantes/administração & dosagem , Antioxidantes/química , Medicamentos de Ervas Chinesas/química , Feminino , Humanos , Hepatopatias/tratamento farmacológico , Mitocôndrias/efeitos da radiação , Mitocôndrias Hepáticas/efeitos da radiação , Substâncias Protetoras/química , Ratos , Ratos Sprague-Dawley
7.
World J Microbiol Biotechnol ; 30(2): 737-45, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24078108

RESUMO

Drosera peltata Smith var. lunata (Buch.-Ham.) C. B. Clarke (DPVL) fractions and plumbagin were tested via broth microdilution techniques on Rhizopus oryzae, Aspergillus flavus, Aspergillus niger, Aspergillus oryzae, Penicillium citrinum. All of the test substances [petroleum ether, chloroform, ethyl acetate, n-butanol fraction and aqueous residue (AR)] except for the AR were active against all the tested strains. The petroleum ether fraction (PEF) was the most active (MIC = 5.86-46.88 µg/ml, MFC = 23.44-93.75 µg/ml) of the five tested substances and therefore, was selected for further analysis. Based on antifungal activity, bioactivity-guided fractionation of the PEF led to the isolation of plumbagin. The structure of plumbagin was elucidated by ¹H and ¹³C NMR. Using HPLC, DPVL was found to be a new source of plumbagin. Reversed-phase HPLC was performed using a mobile phase of water and methanol, and peaks were detected at 254 nm. Plumbagin showed a good linear relationship at concentrations ranging from 0.625 to 10 µg/ml. Both the intraday and the interday precision showed that the method was precise, with RSDs of at least 3% at different concentrations. Recovery rates ranging from 97.86 to 99.94% were observed, which indicate that the method is accurate. The specificity of the method was established by checking the peak purity of plumbagin. For six independent measurements, the average plumbagin content in DPVL was 11.05 ± 0.31 mg/g of dried material. The validated HPLC method provides a new basis for assessing DPVL quality.


Assuntos
Antifúngicos/isolamento & purificação , Drosera/química , Fungos/efeitos dos fármacos , Naftoquinonas/isolamento & purificação , Compostos Fitoquímicos/isolamento & purificação , Antifúngicos/química , Antifúngicos/farmacologia , Cromatografia Líquida de Alta Pressão/métodos , Espectroscopia de Ressonância Magnética , Testes de Sensibilidade Microbiana , Naftoquinonas/química , Naftoquinonas/farmacologia , Compostos Fitoquímicos/química , Compostos Fitoquímicos/farmacologia
8.
Food Chem Toxicol ; 50(7): 2584-8, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22561681

RESUMO

Cultivated Coptis chinensis inflorescence has been highly valued in Chinese tea production for many years. The main alkaloid compounds in C. chinensis inflorescence ethanolic extracts (CE) were identified by high-performance liquid chromatography-mass spectrometry. The detected compounds included jatrorrhizine (4.87 mg/g), coptisine (17.18 mg/g), palmatine (3.32 mg/g), and berberine (31.81 mg/g), as well as columbamine and epiberberine (tentatively identified). CE protective activity against ultraviolet-B (UVB)-induced phototoxicity in a mitochondria model was determined by measuring thiobarbituric acid-reactive substrates, lipid hydroperoxide, conjugated diene, 4-hydroxynonenal, and glutathione. The results showed that CE excellently inhibited UVB-induced lipid peroxidation and glutathione reduction in vitro. This photoprotective effect of CE may be caused by the presence of the abovementioned alkaloid compounds and phenolic compounds that enhances CE antioxidant activity. Therefore, CE possesses potent photoprotective property that may find valuable applications in food industries and in anti-phototoxicity formulations.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Coptis/química , Espectrometria de Massas/métodos , Extratos Vegetais/farmacologia , Raios Ultravioleta
9.
J Ethnopharmacol ; 141(1): 104-10, 2012 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-22343365

RESUMO

AIMS OF THE STUDY: Meconopsis quintuplinervia, a medicinal herb endemic to the Tibetan region, is used to treat hepatitis. The aim of this study is to evaluate the antioxidant potential of the ethanolic extract of this herb using different assays. MATERIALS AND METHODS: The antioxidant capacity of Meconopsis quintuplinervia was investigated using various established in vitro systems. An in vivo study of carbon tetrachloride (CCl(4))-induced antioxidant activity in mice was also conducted by examining the levels of malondialdehyde (MDA) and the activities of antioxidant enzymes, including superoxide dismutase (SOD), catalase (CAT), and glutathione (GSH). RESULTS: The extract showed strong in vitro antioxidant ability. In the in vivo study, CCl(4)-induced oxidative stress caused significant decreases in the SOD, CAT, and GSH levels and a significant increase in the MDA level, most of which were significantly reversed (except for SOD in the liver.) by treatment with the extract and standard Vitamin E. CONCLUSION: This study clearly indicates that the ethanolic extract of Meconopsis quintuplinervia is a valuable source of natural antioxidants. These findings provide scientific support for the traditional use of this herb as a Tibetan medicine for liver diseases.


Assuntos
Antioxidantes/farmacologia , Doença Hepática Induzida por Substâncias e Drogas/prevenção & controle , Etanol/química , Fígado/efeitos dos fármacos , Papaveraceae , Extratos Vegetais/farmacologia , Solventes/química , Animais , Antioxidantes/isolamento & purificação , Benzotiazóis/química , Compostos de Bifenilo/química , Tetracloreto de Carbono , Catalase/metabolismo , Quelantes/farmacologia , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/patologia , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Feminino , Flavonoides/isolamento & purificação , Flavonoides/farmacologia , Glutationa/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Masculino , Malondialdeído/metabolismo , Camundongos , Oxirredução , Estresse Oxidativo/efeitos dos fármacos , Papaveraceae/química , Fenóis/isolamento & purificação , Fenóis/farmacologia , Fitoterapia , Picratos/química , Extratos Vegetais/isolamento & purificação , Plantas Medicinais , Ratos , Ratos Sprague-Dawley , Ácidos Sulfônicos/química , Superóxido Dismutase/metabolismo , Vitamina E/farmacologia
10.
PLoS One ; 7(1): e30147, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22272289

RESUMO

The essential oil extracted from the seeds of dill (Anethum graveolens L.) was demonstrated in this study as a potential source of an eco-friendly antifungal agent. To elucidate the mechanism of the antifungal action further, the effect of the essential oil on the plasma membrane and mitochondria of Aspergillus flavus was investigated. The lesion in the plasma membrane was detected through flow cytometry and further verified through the inhibition of ergosterol synthesis. The essential oil caused morphological changes in the cells of A. flavus and a reduction in the ergosterol quantity. Moreover, mitochondrial membrane potential (MMP), acidification of external medium, and mitochondrial ATPase and dehydrogenase activities were detected. The reactive oxygen species (ROS) accumulation was also examined through fluorometric assay. Exposure to dill oil resulted in an elevation of MMP, and in the suppression of the glucose-induced decrease in external pH at 4 µl/ml. Decreased ATPase and dehydrogenase activities in A. flavus cells were also observed in a dose-dependent manner. The above dysfunctions of the mitochondria caused ROS accumulation in A. flavus. A reduction in cell viability was prevented through the addition of L-cysteine, which indicates that ROS is an important mediator of the antifungal action of dill oil. In summary, the antifungal activity of dill oil results from its ability to disrupt the permeability barrier of the plasma membrane and from the mitochondrial dysfunction-induced ROS accumulation in A. flavus.


Assuntos
Anethum graveolens/química , Antifúngicos/farmacologia , Aspergillus flavus/efeitos dos fármacos , Óleos Voláteis/farmacologia , Óleos de Plantas/farmacologia , Adenosina Trifosfatases/metabolismo , Antifúngicos/isolamento & purificação , Aspergillus flavus/crescimento & desenvolvimento , Aspergillus flavus/metabolismo , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Permeabilidade da Membrana Celular/efeitos dos fármacos , Meios de Cultivo Condicionados/química , Relação Dose-Resposta a Droga , Ergosterol/metabolismo , Citometria de Fluxo , Concentração de Íons de Hidrogênio/efeitos dos fármacos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Proteínas Mitocondriais/metabolismo , Óleos Voláteis/isolamento & purificação , Oxirredutases/metabolismo , Óleos de Plantas/isolamento & purificação , Espécies Reativas de Oxigênio/metabolismo
11.
J Ethnopharmacol ; 136(2): 309-15, 2011 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-21549823

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Swertia chirayita, a medicinal herb endemic to the Tibetan region, is used as a special remedy for liver disorders. The hepatoprotective activity of its plant extracts has been associated with its antioxidant activity. This paper aims to investigate the in vitro and in vivo antioxidant effects of Swertia chirayita extracts (SCE). MATERIALS AND METHODS: Antioxidant ability of Swertia chirayita was investigated by employing several established in vitro methods. In vivo antioxidant activity was tested against CCl(4)-induced toxicity in mice. The levels and activities of malondialdehyde (MDA) and antioxidant enzymes, including superoxide dismutase (SOD), catalase (CAT), and glutathione (GSH), were then assayed using standard procedures. RESULTS: SCE exhibited strong antioxidant ability in vitro. The liver and kidney of CCl(4)-intoxicated animals exhibited a significant (p<0.001) decrease in SOD, CAT, and GSH levels. Additionally, these organs exhibited a significant (p<0.001) increase in MDA level. CCl(4) did not exhibit toxicity on mice treated with SCE and Vitamin E. The effects of Swertia chirayita (three dosages) were comparable to those of Vitamin E, except in MDA level in the liver and GSH level in the kidney (p<0.05). CONCLUSION: This study suggests that the ethanolic extract of Swertia chirayita possesses in vitro and in vivo antioxidant effects. This supports the traditional use of Swertia chirayita in Tibetan medicine to cure liver diseases.


Assuntos
Antioxidantes/uso terapêutico , Doença Hepática Induzida por Substâncias e Drogas/prevenção & controle , Fitoterapia , Extratos Vegetais/uso terapêutico , Swertia , Animais , Antioxidantes/metabolismo , Antioxidantes/farmacologia , Tetracloreto de Carbono , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Rim/efeitos dos fármacos , Rim/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Malondialdeído/metabolismo , Camundongos , Camundongos Endogâmicos , Extratos Vegetais/farmacologia , Vitamina E/farmacologia , Vitamina E/uso terapêutico
12.
Plant Foods Hum Nutr ; 66(2): 175-80, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21523412

RESUMO

The inflorescence of cultivated Coptis chinensis has been valued for tea production for many years in China. The antioxidant activities of C. chinensis inflorescence extracts prepared by various solvents were investigated by using several established in vitro systems: 2,2'-azinobis(3-ethylbenzthiazoline-6-sulphonic acid (ABTS), α,α-diphenyl-ß-picrylhydrazyl (DPPH) and superoxide radical scavenging assays, reducing power assay, and ferrothiocyanate (FTC) and thiobarbituric acid (TBA) assays. The results showed that the 70% ethanol extract (EE) had the strongest antioxidant activity in vitro among the various extracts. Based on the in vitro results, EE was used to evaluate the antioxidant activity of C. chinensis inflorescence in vivo. The liver and kidney of intoxicated animals showed a significant decrease in superoxide dismutase (SOD), catalase (CAT) and glutathione (GSH) levels, while the malondialdehyde (MDA) level showed a significant increase. These changes were significantly reversed after treatment with EE and the standard vitamin E. Thus, the C. chinensis inflorescence may be a valuable natural source that can be applicable to food industries.


Assuntos
Antioxidantes/farmacologia , Coptis/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Animais , Antioxidantes/química , Benzotiazóis/química , Benzotiazóis/metabolismo , Compostos de Bifenilo/química , Compostos de Bifenilo/metabolismo , Catalase/efeitos dos fármacos , Catalase/metabolismo , China , Avaliação Pré-Clínica de Medicamentos , Etanol/química , Sequestradores de Radicais Livres/metabolismo , Glutationa/metabolismo , Inflorescência/química , Rim/efeitos dos fármacos , Rim/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Malondialdeído/metabolismo , Camundongos , Picratos/química , Picratos/metabolismo , Ácidos Sulfônicos/química , Ácidos Sulfônicos/metabolismo , Superóxido Dismutase/efeitos dos fármacos , Superóxido Dismutase/metabolismo , Tiobarbitúricos/química , Tiobarbitúricos/metabolismo , Vitamina E/farmacologia
13.
Int J Food Microbiol ; 145(2-3): 464-70, 2011 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-21320730

RESUMO

The essential oil extracted from the fruits of Cicuta virosa L. var. latisecta Celak was tested in vitro and in vivo against four foodborne fungi, Aspergillus flavus, Aspergillus oryzae, Aspergillus niger, and Alternaria alternata. Forty-five different components accounting for 98.4% of the total oil composition were identified by gas chromatography-mass spectrometry. The major components were γ-terpinene (40.92%), p-cymene (27.93%), and cumin aldehyde (21.20%). Antifungal activity was tested by the poisoned food technique against the four fungi. Minimum inhibitory concentration against the fungi was 5 µL/mL and percentage inhibition of mycelial growth was determined at day 9. The essential oil had a strong inhibitory effect on spore production and germination in all tested fungi proportional to concentration. The oil exhibited noticeable inhibition on dry mycelium weight and synthesis of aflatoxin B1 (AFB1) by A. flavus, completely inhibiting AFB(1) production at 4 µL/mL. The effect of the essential oil on inhibition of decay development in cherry tomatoes was tested in vivo by exposing inoculated and control fruit to essential oil vapor at a concentration of 200 µL/mL. Results indicated that the essential oil from C. virosa var. latisecta (CVEO) has potential as a preservative to control food spoilage.


Assuntos
Antifúngicos/farmacologia , Cicuta/química , Fungos Mitospóricos/efeitos dos fármacos , Óleos Voláteis/química , Óleos de Plantas/química , Aflatoxina B1/biossíntese , Antifúngicos/química , Benzaldeídos/química , Benzaldeídos/farmacologia , Monoterpenos Cicloexânicos , Cimenos , Conservação de Alimentos , Cromatografia Gasosa-Espectrometria de Massas , Solanum lycopersicum/microbiologia , Testes de Sensibilidade Microbiana , Fungos Mitospóricos/crescimento & desenvolvimento , Fungos Mitospóricos/metabolismo , Monoterpenos/química , Monoterpenos/farmacologia , Micélio/efeitos dos fármacos , Micélio/crescimento & desenvolvimento , Óleos Voláteis/farmacologia , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Óleos de Plantas/farmacologia , Esporos Fúngicos/efeitos dos fármacos , Esporos Fúngicos/crescimento & desenvolvimento
14.
Food Chem Toxicol ; 49(1): 185-90, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20971152

RESUMO

The antioxidant properties of different extracts of Halenia elliptica was investigated by employing various established in vitro systems. The results showed that various extracts possessed strong antioxidant activity in vitro, and the 70% methanol extract (ME) had the strongest antioxidant activity. Based on our in vitro results, ME was used for investigating the antioxidant properties of H. ellipticain vivo. The liver and kidney of CCl(4)-intoxicated animals exhibited a significant decrease in superoxide dismutase (SOD), catalase (CAT) and glutathione (GSH) levels. Additionally, these organs exhibited a significant increase in the level of malondialdehyde (MDA). These changes were significantly reversed, in a dose-dependent manner, after treatment with ME and the standard treatment Vitamin E. Thus, it may be concluded that the ME possesses potent antioxidant properties, and might be valuable natural source of antioxidants that could be applicable to both the medical and food industries.


Assuntos
Antioxidantes/farmacologia , Gentianaceae/química , Extratos Vegetais/farmacologia , Animais , Catalase/metabolismo , Glutationa/metabolismo , Técnicas In Vitro , Malondialdeído/metabolismo , Ratos , Ratos Sprague-Dawley , Superóxido Dismutase/metabolismo
15.
Meat Sci ; 87(1): 46-53, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20869815

RESUMO

Lotus (Nelumbo nucifera) is an extensively cultivated vegetable in eastern Asia, particularly in China. Both lotus rhizome knot (LRK) and lotus leaf (LL) are waste products of the lotus industry. Extracts from LRK and LL are proposed as antioxidants for meat. Porcine and bovine ground meat samples were subjected to three treatments: CONTROL (with no additives), LRK (lotus rhizomes knot extract 3% w/w), and LL (lotus leaf extract 3% w/w). Raw and cooked samples were stored at 4°C and the antioxidant activity was determined at 1, 3, 6 and 10 days. Antioxidant activity was significantly increased in all meat samples with the addition of both LRK and LL, but LRK was more effective against lipid oxidation. The results show the potential for using LRK and LL extracts in the meat industry to prolong shelf life.


Assuntos
Antioxidantes/farmacologia , Peroxidação de Lipídeos/efeitos dos fármacos , Carne/análise , Nelumbo , Extratos Vegetais/farmacologia , Folhas de Planta , Rizoma , Animais , Bovinos , Suínos
16.
Zhonghua Bing Li Xue Za Zhi ; 40(10): 660-3, 2011 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-22321542

RESUMO

OBJECTIVE: To investigate the epidermal growth factor receptor (EGFR) gene mutation profile and related clinicopathological features in Chinese patients with non-small cell lung carcinoma (NSCLC). METHODS: Optimized oligonucleotide probe method was applied to detect EGFR mutations involving exons 18 - 21 using formalin fixed paraffin embedded tissue specimens of 309 NSCLC patients. The relationship between EGFR mutations and clinicopathological features were analyzed. RESULTS: The overall EGFR mutation rate was 34% (105/309) in this study cohort. Mutation rates in male and female were 30.4% (56/184) and 39.2% (49/125), respectively. The mutation rate was higher in patients less than 60 years of age, non-smokers and adenocarcinoma subtype than in their counterparts (P<0.05), with the percentage of 40.5% (87/215), 40.2% (51/127), 38.8% (78/201), respectively. The EGFR mutation types included exon 18 G719X mutation (5.7%, 6/105), exon 19 deletion (39.0%, 41/105) and exon 21 L858R mutation (55.2%, 58/105). In large cell undifferentiated carcinomas and squamous cell carcinomas, EGFR mutation rates were 22.2% (58/105) and 3/14, respectively. The overall mutation rate of exon 18 was low, but the proportion of its mutation was higher in squamous and adenosquamous carcinomas than in adenocarcinomas. CONCLUSIONS: There is a higher EGFR mutation rate in female, age of less than 60 years, non-smoker and adenocarcinoma among Chinese patients with NSCLC. Optimized oligonucleotide probe method is a sensitive and convenient method for the detection of EGFR mutations.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/genética , Receptores ErbB/genética , Genes erbB-1/genética , Neoplasias Pulmonares/genética , Mutação , Adenocarcinoma/genética , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Carcinoma Adenoescamoso/genética , Carcinoma de Células Grandes/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma de Células Escamosas/genética , Éxons , Feminino , Humanos , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Taxa de Mutação , Fatores Sexuais , Fumar
17.
J Ethnopharmacol ; 131(2): 276-81, 2010 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-20600758

RESUMO

AIMS OF STUDY: Halenia elliptica, a medicinal herb of Tibetan origin, was commonly used in folk medicine to treat hepatitis. The aim of the present study is to evaluate the hepatoprotective and antioxidant activity of Halenia elliptica against experimentally induced liver injury. MATERIALS AND METHODS: The antioxidant property of methanolic extract (ME) of Halenia elliptica was investigated by employing various established in vitro systems. The ME of Halenia elliptica was studied here for its hepatoprotective effects against CCl(4)-induced liver toxicity in rats. Activity was measured by monitoring the levels of alanine aminotransferase (ALT), aspartate transaminase (AST), alkaline phosphatase (ALP), and total bilirubin. RESULTS: The ME possessed strong antioxidant activity in vitro. The results of CCl(4)-induced liver toxicity experiment showed that rats treated with the ME of Halenia elliptica (100 mg/kg and 200 mg/kg), and also the standard treatment, silymarin (50 mg/kg), showed a significant decrease in ALT, AST, ALP, and total bilirubin levels, which were all elevated in the CCl(4) group (p<0.01). The results observed after administration of 100 mg/kg ME were comparable to those of silymarin at 50 mg/kg (p>0.05). The ME did not show any mortality at doses up to 2000 g/kg body weight. CONCLUSION: These results seem to support the traditional use of Halenia elliptica in pathologies involving hepatotoxicity, and the possible mechanism of this activity may be due to strong free radical-scavenging and antioxidant activities of ME.


Assuntos
Antioxidantes/uso terapêutico , Doença Hepática Induzida por Substâncias e Drogas/prevenção & controle , Gentianaceae , Fígado/efeitos dos fármacos , Fitoterapia , Extratos Vegetais/uso terapêutico , Alanina Transaminase/sangue , Fosfatase Alcalina/sangue , Animais , Antioxidantes/farmacologia , Aspartato Aminotransferases/sangue , Bilirrubina/sangue , Tetracloreto de Carbono , Doença Hepática Induzida por Substâncias e Drogas/sangue , Feminino , Fígado/metabolismo , Masculino , Extratos Vegetais/farmacologia , Ratos , Ratos Sprague-Dawley , Silimarina/farmacologia , Silimarina/uso terapêutico
18.
J Agric Food Chem ; 58(1): 441-8, 2010 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-19919095

RESUMO

This study was designed to examine the composition of extracts and essential oil components from Nelumbo nucifera leaves from the principal habitats in China. The amounts of phenolics, flavonoids, and proanthocyanidins in the lotus leaf extracts varied widely, ranging from 354 to 487 mg/g gallic acid equivalents, from 172 to 236 mg/g rutin equivalents, and from 124 to 179 mg/g catechin equivalents, respectively. All of the extracts had strong antioxidant activity in comparison to the standard compounds butylated hydroxytoluene and vitamin C. Wild lotus samples from Baiyangdian Lake and Weishan Lake exhibited a stronger free radical scavenging effect and greater reducing power than the cultural samples, but no such differences were observed in the inhibition of lipid oxidation. Chemical variation in the essential oils from the various samples was analyzed by GC-MS. The main constituents were l-(+)-ascorbic acid 2,6-dihexadecanoate (0-33.5%), trans-phytol (5.1-24.1%), hexahydrofarnesyl acetone (5.6-15.3%), pentadecyl acrylate (2.2-12.4%), geranyl acetone (1.9-8.0%), and beta-ionone (0-8.0%). The rhizome lotus and seed lotus samples were clustered into separate groups by hierarchical cluster analysis according to the composition of the corresponding essential oils. No significant relationship was found between essential oil composition and geographical distribution of the 11 populations. However, the results indicated that region of origin and growing conditions could significantly affect both the bioactivities of the lotus leaf and the content of bioactive compounds in the leaves. Thus, the existence of chemical polymorphism in the N. nucifera leaf in China was demonstrated.


Assuntos
Antioxidantes/análise , Nelumbo/química , Óleos Voláteis/análise , Extratos Vegetais/análise , China , Sequestradores de Radicais Livres/análise , Folhas de Planta/química
19.
Genetica ; 135(2): 233-43, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18500655

RESUMO

Magnolia officinalis subsp. biloba, a traditional Chinese medicinal plant, experienced severe declines in the number of populations and the number of individuals in the late 20th century due to the widespread harvest of the subspecies. A large-scale cultivation program was initiated and cultivated populations rapidly recovered the loss in individual plant numbers, but wild populations remained small as a consequence of cutting. In this study, the levels of genetic variation and genetic structure of seven wild populations and five domestic populations of M. officinalis subsp. biloba were estimated employing an AFLP methodology. The plant exhibited a relatively high level of intra-population genetic diversity (h = 0.208 and H(j) = 0.268). The cultivated populations maintained approximately 95% of the variation exhibited in wild populations, indicating a slight genetic bottleneck in the cultivated populations. The analysis of genetic differentiation revealed that most of the AFLP diversity resided within populations both for the wild group (78.22%) and the cultivated group (85.92%). Genetic differentiation among populations in the wild group was significant (F(ST) = 0.1092, P < 0.005), suggesting wild population level genetic structure. Principal coordinates analysis (PCO) did not discern among wild and cultivated populations, indicating that alleles from the wild population were maintained in the cultivated gene pool. Results from the present study provide important baseline data for effectively conserving the genetic resources of this medicinal subspecies.


Assuntos
Variação Genética , Magnolia/genética , Plantas Medicinais/genética , Análise do Polimorfismo de Comprimento de Fragmentos Amplificados/métodos , China , DNA de Plantas/genética , Genética Populacional , Magnolia/classificação , Medicina Tradicional Chinesa , Filogenia , Plantas Medicinais/classificação
20.
Dis Colon Rectum ; 50(11): 1887-98, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17882488

RESUMO

PURPOSE: The prognosis varies greatly in colorectal carcinoma patients, even in the same stage. We examined the association between the expression of matrix metalloproteinases-2, carcinoembryonic antigen, p27 kip1, and clinicopathologic features in patients with colorectal carcinoma to identify a possible panel of tumor markers in predicting prognosis of colorectal carcinoma. METHODS: The expressions of three individual markers in 127 colorectal carcinoma cases were analyzed by immunohistochemistry method. Univariate and multivariate analysis were performed to analyze the expression with the disease-free survival time in colorectal carcinoma. RESULTS: High expression of matrix metalloproteinases-2, carcinoembryonic antigen, and low expression of p27 kip1 were related to poor prognosis in univariate analysis (P = 0.0002; P < 0.0001; P = 0.0008). The expression of matrix metalloproteinases-2, carcinoembryonic antigen, p27 kip1, and tumor differentiation were independent prognostic factors for disease-free survival by Cox regression analysis. The coexpression panel of matrix metalloproteinases-2, carcinoembryonic antigen, and p27 kip had significant prognostic value in all patients (P AB = 0.0103; P(BC) = 0.0068; P CD = 0.0117). Multivariate analysis with Cox regression reveals that coexpression of matrix metalloproteinases-2, carcinoembryonic antigen, and p27 kip1 were independent prognostic factors as tumor differentiation in colorectal carcinoma. In different stages, coexpression tumor markers functioned in Stages II and III but not in the 19 cases of Stage I. The reason might be the number of patients was too small. CONCLUSIONS: The results of this study provided further evidence that the combination of tumor markers of matrix metalloproteinases-2, carcinoembryonic antigen, and p27 kip1 was more informative than any single tumor marker alone for the disease-free survival stratification of colorectal carcinoma. Coexpression of matrix metalloproteinases-2, carcinoembryonic antigen, and p27 kip1 might be a useful survival stratification panel for clinical management.


Assuntos
Adenocarcinoma/metabolismo , Adenocarcinoma/enfermagem , Antígeno Carcinoembrionário/metabolismo , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/mortalidade , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Metaloproteinase 2 da Matriz/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Inibidor de Quinase Dependente de Ciclina p27 , Intervalo Livre de Doença , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Prognóstico , Análise de Sobrevida
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