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1.
Planta ; 254(3): 50, 2021 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-34386845

RESUMO

MAIN CONCLUSION: Overexpression of the leaf color (Lc) gene in Ma bamboo substantially increased the accumulation level of anthocyanin, and improved plant tolerance to cold and drought stresses, probably due to the increased antioxidant capacity. Most bamboos, including Ma bamboo (Dendrocalamus latiflorus Munro), are naturally evergreen and sensitive to cold and drought stresses, while it's nearly impossible to make improvements through conventual breeding due to their long and irregular flowering habit. Moreover, few studies have reported bamboo germplasm innovation through genetic engineering as bamboo genetic transformation remains difficult. In this study, we have upregulated anthocyanin biosynthesis in Ma bamboo, to generate non-green Ma bamboo with increased abiotic stress tolerance. By overexpressing the maize Lc gene, a bHLH transcription activator involved in the anthocyanin biosynthesis in Ma bamboo, we generated purple bamboos with increased anthocyanin levels including cyanidin-3-O-rutinoside, peonidin 3-O-rutinoside, and an unknown cyanidin pentaglycoside derivative. The expression levels of 9 anthocyanin biosynthesis genes were up-regulated. Overexpression of the Lc gene improved the plant tolerance to cold and drought stress, probably due to increased antioxidant capacity. The levels of the cold- and drought-related phytohormone jasmonic acid in the transgenic plants were also enhanced, which may also contribute to the plant stress-tolerant phenotypes. High anthocyanin accumulation level did not affect plant growth. Transcriptomic analysis showed higher expressions of genes involved in the flavonoid pathway in Lc transgenic bamboos compared with those in wild-type ones. The anthocyanin-rich bamboos generated here provide an example of ornamental and multiple agronomic trait improvements by genetic engineering in this important grass species.


Assuntos
Secas , Regulação da Expressão Gênica de Plantas , Antocianinas , Resposta ao Choque Frio , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/metabolismo
2.
Int J Biol Macromol ; 162: 533-547, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-32565302

RESUMO

This study aimed to explore the basic structural features of phosphorylated Pleurotus ostreatus polysaccharide (PPOP) and study the protective effect of PPOP on liver injury induced by carbon tetrachloride in male Kunming mice. The phosphorylated polysaccharide was prepared from the natural polysaccharide extracted from Pleurotus ostreatus (POP). The structures of PPOP and POP were characterized by FT-IR, ESEM spectroscopy, and Congo red test. Chemical composition analysis revealed that PPOP was mainly composed of rhamnose, galacturonic acid, and xylose in a molar ratio of 0.10: 1.98: 1.00. Structural analysis indicated that PPOP had multi-strand structure and the absorption peaks of PO and P-O-C. Furthermore, animal experiments showed that the hepatoprotective effect of PPOP against liver injury was reflected by decreasing the levels of alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, total cholesterol, trilaurin, and low-density lipoprotein cholesterol in the serum, increasing the content of high-density lipoprotein cholesterol and albumin in blood, reducing the content of malondialdehyde and promoting the activity of antioxidant enzymes in liver. PPOP exhibited stronger hepatoprotective effect and antioxidant activity in vivo than POP. The final results indicated that PPOP could be used in the treatment of chemical-induced hepatotoxicity based on the above biological research.


Assuntos
Intoxicação por Tetracloreto de Carbono/tratamento farmacológico , Doença Hepática Induzida por Substâncias e Drogas/tratamento farmacológico , Polissacarídeos Fúngicos , Pleurotus/química , Animais , Intoxicação por Tetracloreto de Carbono/metabolismo , Intoxicação por Tetracloreto de Carbono/patologia , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/patologia , Polissacarídeos Fúngicos/química , Polissacarídeos Fúngicos/isolamento & purificação , Polissacarídeos Fúngicos/farmacologia , Masculino , Camundongos , Relação Estrutura-Atividade
3.
Int J Biol Macromol ; 137: 504-511, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31229542

RESUMO

This work aims to analyze the immunomodulatory effect of pomegranate peel polysaccharides (PPP) on the immunosuppressed mice induced by cyclophosphamide (CTX). All the mice were divided into 6 groups randomly and the immunoprophylaxis mice were administrated with PPP [100, 200, 400 mg/(kg·d)] by gavage for consecutive 28 days. The results showed that PPP can slow down the decline of body weight and increase the immune organ index of the immunosuppressed mice. Compared to the model mice, the enzymatic activity of LDH (lactate dehydrogenase) and ACP (acid phosphatase) of the mice spleen administrated with PPP by gavage was enhanced significantly. PPP stimulated proliferation and secretion of splenic lymphocytes and markedly increased the immunoglobulin (Ig-A, Ig-G and Ig-M) expression and the release of cytokines (TNF-α, IL-2 and INF-γ) in cyclophosphamide-induced immunosuppressed mice. Hepatic antioxidant enzymatic activities of T-AOC (total antioxidant capacity), T-SOD (total superoxide dismutase), GSH-PX (glutathione peroxidase) and CAT (catalase) were markedly increased when the mice were administrated with high dosage of PPP. So it can be concluded that PPP could be used as an efficacious adjacent immunopotentiating therapy or an alternative means in lessening chemotherapy-induced immunosuppression, and also can be utilized as immunostimulants for food and pharmaceutical industries.


Assuntos
Antioxidantes/farmacologia , Fatores Imunológicos/farmacologia , Imunossupressão , Polissacarídeos/farmacologia , Romã (Fruta)/química , Fosfatase Ácida/metabolismo , Animais , Antioxidantes/química , Contagem de Células Sanguíneas , Peso Corporal/efeitos dos fármacos , Catalase/metabolismo , Fenômenos Químicos , Glutationa/metabolismo , Fatores Imunológicos/química , L-Lactato Desidrogenase/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Malondialdeído/metabolismo , Camundongos , Polissacarídeos/química , Superóxido Dismutase/metabolismo , Linfócitos T/citologia , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologia
4.
Polymers (Basel) ; 11(4)2019 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-30960591

RESUMO

The magadiite⁻magnetite (MAG⁻Fe3O4) nanocomposite has great potential applications in the field of biomaterials research. It has been used as a novel magnetic sorbent, prepared by co-precipitation method. It has the dual advantage of having the magnetism of Fe3O4 and the high adsorption capacity of pure magadiite (MAG). MAG⁻Fe3O4 was characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and vibrating sample magnetometer (VSM). The results showed that Fe3O4 nanoparticles were deposited on the interlayer and surface of magadiite. MAG⁻Fe3O4 was treated as an adsorbent for methylene blue (MB) removal from aqueous solutions. The adsorption properties of MAG⁻Fe3O4 were investigated on methylene blue; however, the results showed that the adsorption performance of MAG⁻Fe3O4 improved remarkably compared with MA and Fe3O4. The adsorption capacity of MAG⁻Fe3O4 and the removal ratio of methylene blue were 93.7 mg/g and 96.2%, respectively (at 25 °C for 60 min, pH = 7, methylene blue solution of 100 mg/L, and the adsorbent dosage 1 g/L). In this research, the adsorption experimental data were fitted and well described using a pseudo-second-order kinetic model and a Langmuir adsorption isotherm model. The research results further showed that the adsorption performance of MAG⁻Fe3O4 was better than that of MAG and Fe3O4. Moreover, the adsorption behavior of MB on MAG⁻Fe3O4 was investigated to fit well in the pseudo-second-order kinetic model with the adsorption kinetics. The authors also concluded that the isothermal adsorption was followed by the Langmuir adsorption isotherm model; however, it was found that the adsorption of the MAG⁻Fe3O4 nanocomposite was a monolayer adsorption.

5.
Carbohydr Polym ; 202: 461-469, 2018 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-30287023

RESUMO

This proposed work aimed to investigate the chemical characteristic, antioxidant capacities and hepatoprotection effect of pomegranate peel polysaccharides (PPP) on CCl4-induced oxidative damage in mice. PPP was identified as the acidic heteropolysaccharides by HPLC methods. In vitro test showed that PPP had excellent reducing power and scavenging effects against free radicals. Administration of PPP (50, 100 and 200 mg/kg·bw) in mice before the injection of CCl4 could observably antagonize the increased serum alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase and hepatic malonaldehyde level in CCl4-induced mice, especially administrated with 200 mg/kg·bw of PPP. Hepatic enzymatic activities of total superoxide dismutase, glutathione peroxidase, catalase and non-enzymatic activity of glutathione were markedly increased at high dosage of PPP, respectively. In addition, histopathological observation of liver further proved these biochemical characteristics. Therefore, it can be concluded that PPP exhibits strong protective effects against CCl4-induced liver injury in mice.


Assuntos
Antioxidantes/farmacologia , Doença Hepática Induzida por Substâncias e Drogas/prevenção & controle , Lythraceae/química , Polissacarídeos/farmacologia , Animais , Antioxidantes/química , Antioxidantes/isolamento & purificação , Tetracloreto de Carbono , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/patologia , Relação Dose-Resposta a Droga , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Masculino , Camundongos , Camundongos Endogâmicos , Polissacarídeos/química , Polissacarídeos/isolamento & purificação , Relação Estrutura-Atividade
6.
Int J Biol Macromol ; 109: 244-253, 2018 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-29242125

RESUMO

In this work, based on response surface methodology (RSM), an optimized method of extracting water-soluble polysaccharide from pomegranate peel (PPP) with pectinase was proposed. Additionally, the chemical composition and the antioxidant activities of the extracted PPP were studied. The effects of three factors of enzymolysis time, ratio of liquid to solid and dosage of enzyme on the PPP yield were investigated. The experimental results showed that the optimal conditions were as following: enzymolysis time 19.70 min, ratio of liquid to solid 20.5:1(mL/g), dosage of enzyme 0.68%. Under the best conditions, the maximum PPP yield was 27.3 ±â€¯0.08%. FT-IR and GC-MS revealed that PPP was the typical acidic heteropolysaccharides and mainly consisted of d-mannose (19.30%), d-galactose (47.93%) and l-arabinose (23.08%). Moreover, the antioxidant activity assay in vitro showed that PPP exhibited strong reducing power and good scavenging activities on superoxide anion, hydroxyl, and DPPH radicals. The PPP extracted with pectinase had excellent antioxidant properties and could be developed into a new type of dietary supplement or functional food.


Assuntos
Antioxidantes/química , Antioxidantes/farmacologia , Lythraceae/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Polissacarídeos/química , Polissacarídeos/farmacologia , Fracionamento Químico , Sequestradores de Radicais Livres/química , Sequestradores de Radicais Livres/farmacologia , Concentração de Íons de Hidrogênio , Oxirredução/efeitos dos fármacos , Compostos Fitoquímicos/química , Poligalacturonase/química , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura
7.
J Thorac Dis ; 9(8): 2476-2483, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28932553

RESUMO

BACKGROUND: Sleep apnoea hypopnoea syndrome (SAHS) is characterised by repetitive nocturnal hypoxemia and has a high prevalence among patients with acute myocardial infarction (AMI). But there are few studies on patients with AMI undergoing emergency primary percutaneous coronary intervention (pPCI). In this study, we want to find the prevalence of SAHS among patients with AMI undergoing emergency pPCI and determine whether SAHS would worsen the condition among these people, and especially affect the damage degree of the coronary artery. METHODS: Over four months, 95 patients admitted for the first time for AMI were observed. All of them had emergency primary PCIs. A total of 86 patients accepted the sleep study and were divided into four groups according to the apnoea hypopnoea index (AHI): SAHS was diagnosed when AHI ≥5/h and was defined as mild for AHI ≥5/h and <15/h, moderate for AHI ≥15/h and <30/h, and severe for AHI ≥30/h. On the contrary, the patients whose AHI <5/h were Non-SAHS. And the characteristics of the patients among these four groups were compared. According to the time of chest pain onset, the number of the patients between SAHS and non-SAHS, and patients' AHI during three intervals of one day were measured and compared; Makers including the sensitivity of serum troponin T (hs-TnT), creatine kinase isoenzyme MB (CK-MB), left ventricular ejection fraction (LVEF), pro-brain-type natriuretic peptide (pro-BNP), Gensini score and collateral vessels between the SAHS and non-SAHS were compared. And the relationships between the AHI of these patients and the markers were analysed. RESULTS: Of the 86 patients studied, 65 had SAHS, representing a SAHS prevalence of 75.58% among patients with AMI undergoing emergency pPCI. There were significant differences in average ages, smoking and arrhythmia (P<0.05) between these four groups. There was no significant difference between AMI patients with or without SAHS regarding the day-night pattern. But there showed significant differences between SAHS and non-SAHS in Gensini score (P<0.05) and pro-BNP (P<0.05). Also, there were positive correlations between AHI and Gensini score (r=0.490, P<0.05) and pro-BNP (r=0.338, P<0.05). CONCLUSIONS: Among patients with AMI undergoing emergency pPCI, there is a high prevalence of SAHS. There are also positive correlations between AHI and Gensini score, and pro-BNP. Therefore, guided by the results, should we conduct a routine screening to those patients normally and could we relieve the damage to the coronary artery by curing the SAHS?

8.
Front Plant Sci ; 8: 1298, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28798758

RESUMO

Genetic engineering technology has been successfully used in many plant species, but is limited in woody plants, especially in bamboos. Ma bamboo (Dendrocalamus latiflorus Munro) is one of the most important bamboo species in Asia, and its genetic improvement was largely restricted by the lack of an efficient regeneration and transformation method. Here we reported a plantlet regeneration and Agrobacterium-mediated transformation protocol by using Ma bamboo young shoots as explants. Under our optimized conditions, embryogenic calluses were successfully induced from the excised young shoots on callus induction medium and rapidly grew on callus multiplication medium. Shoots and roots were regenerated on shoot induction medium and root induction medium, respectively, with high efficiency. An Agrobacterium-mediated genetic transformation protocol of Ma bamboo was established, verified by PCR and GUS staining. Furthermore, the maize Lc gene under the control of the ubiquitin promoter was successfully introduced into Ma bamboo genome and generated an anthocyanin over-accumulation phenotype. Our methods established here will facilitate the basic research as well as genetic breeding of this important bamboo species. Key achievements: A stable and high efficiency regeneration and Agrobacterium-mediated transformation protocol for Ma bamboo from vegetative organ is established.

9.
Food Chem ; 177: 139-46, 2015 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-25660869

RESUMO

Ultrasonic technique was employed to extract polysaccharides from pomegranate peel. The optimal conditions for ultrasonic extraction of pomegranate peel polysaccharide (PPP) were determined by response surface methodology. Box-Behnken design was applied to evaluate the effects of four independent variables (ratio of water to raw material, extraction time, extraction temperature, ultrasonic power) on the yield of PPP. The correlation analysis of mathematical-regression models indicated that quadratic polynomial model could be employed to optimize the ultrasonic extraction of PPP. The optimum extraction parameters were as follows: ratio of water to raw material, 24 ml/g; extraction time, 63 min; extraction temperature, 55°C; and ultrasonic power, 148 W. Under these conditions, the polysaccharide yield was 13.658 ± 0.133% for the pomegranate peel, which well matches with the predicted value.


Assuntos
Frutas/química , Lythraceae/química , Polissacarídeos/química , Ultrassom/métodos , Polissacarídeos/isolamento & purificação , Extração em Fase Sólida , Temperatura , Água
10.
Food Chem ; 141(2): 1295-300, 2013 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-23790916

RESUMO

A study about the ultrasonic extraction, antioxidant capacity and identification of phenolics from Semen Astragali Complanati was undertaken. The optimised extraction condition with an orthogonal experiment design of L9(3(4)) was 50°C, 30min and 15:1 (methanol solution:sample, mL:g). An extraction yield of 40.12±1.10mg gallic acid/g dry seed and the antioxidant capacity of 0.85±0.13mg dry extract/mg DPPH were obtained with the optimum condition, respectively. For each extraction set, the antioxidant capacity by 2,2-diphenyl-1-picrylhydrazyl radical assay highly correlated to its total phenolic content by Folin-Ciocalteu method. Twelve phenolic components obtained with the optimised extraction procedure were tentatively identified by Ultra Performance Liquid Chromatography coupled with Q-TOF Mass Spectrometer (UPLC-Q-TOF) according to their mass spectrometry, UV/vis spectrometry, and related literature reports. Furthermore, the ultrasonic effect on the particles' microstructure of Semen Astragali Complanati was also investigated by scanning electron microscopy (SEM) analysis.


Assuntos
Antioxidantes/química , Antioxidantes/isolamento & purificação , Astrágalo (Planta)/química , Fenóis/química , Fenóis/isolamento & purificação , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Espectrometria de Massas
11.
Carbohydr Polym ; 92(2): 1197-202, 2013 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-23399146

RESUMO

In this study, response surface methodology was employed to optimize the extraction process of crude polysaccharides from Pomegranate peel with water. Three independent and main variables, including extraction time (h), extraction temperature (°C) and ratio of water to raw material (ml/g), which were of significance for the yields of polysaccharides were studied and the Box-Behnken design was based on the results of a single-factors test. The experimental data were fitted to a second-order polynomial equation using multiple regression analysis and also examined using the appropriate statistical methods. The best extraction conditions are as follows: extraction time 1.9h, extraction temperature 98 °C, ratio of water to raw material 37 ml/g. Under the optimization conditions, the experimental yield was 10.358%, which was well matched with the predictive yield of 10.423%.


Assuntos
Fracionamento Químico/métodos , Lythraceae/química , Polissacarídeos/isolamento & purificação , Estatística como Assunto/métodos , Modelos Estatísticos , Temperatura , Fatores de Tempo , Água/química
12.
J Sci Food Agric ; 93(1): 149-56, 2013 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-22696075

RESUMO

BACKGROUND: Lycium barbarum polysaccharide (LBP), isolated with boiling water from the famous Chinese medicinal herb Lycium barbarum fruits, is one of the most important functional constituents in Lycium barbarum. In this study the effects of LBP on cell proliferation, cell cycle and apoptosis in human cervical carcinoma cells (HeLa cells) were investigated. RESULTS: LBP could inhibit the proliferation of HeLa cells by changing cell cycle distribution and inducing apoptosis. In addition, the loss of mitochondrial transmembrane potential (Δψm ) was observed by flow cytometry and the increase of intracellular Ca(2+) concentration was detected by laser scanning confocal microscope in apoptotic cells. At the same time, the nitric oxide content, nitric oxide synthase and inducible nitric oxide synthase activities were also increased. CONCLUSION: The inhibitory effect of LBP on the proliferation of HeLa cells was caused by inducing apoptosis through the mitochondrial pathway. The results showed that LBP can be developed as a potential chemotherapeutic agent candidate against human cervical cancer.


Assuntos
Antineoplásicos Fitogênicos/uso terapêutico , Medicamentos de Ervas Chinesas/uso terapêutico , Lycium/química , Fitoterapia , Neoplasias do Colo do Útero/tratamento farmacológico , Antineoplásicos Fitogênicos/farmacologia , Apoptose , Cálcio/metabolismo , Ciclo Celular/efeitos dos fármacos , Proliferação de Células , Medicamentos de Ervas Chinesas/farmacologia , Feminino , Frutas/química , Células HeLa , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Neoplasias do Colo do Útero/metabolismo
13.
Toxicol In Vitro ; 21(5): 820-6, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17367985

RESUMO

Soyasaponins are present in legumes and soybeans are the primary dietary source of saponins. SS-II, the second fraction of soyasaponins, was separated by column chromatographic method with D101A macroporous resin from soybean. In this paper, at the concentration range of 100-400 mg/L, SS-II had obvious cytotoxic effect on Hela cells by MTT assay. After Hela cells were treated with SS-II, typical apoptotic morphological changes, including nuclear fragmentation, cytoplasm shrinkage and decrease of cell volume, were observed by fluorescence microscope, transmission electron microscope (TEM) and confocal laser scanning microscope (CLSM), respectively. Terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay also confirmed that SS-II-treated Hela cells showed apoptotic features. The results suggested that soyasaponins were a potential antitumor compound and the apoptosis induced by soyasaponins was a key antitumor mechanism.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Saponinas/farmacologia , Soja/química , Fragmentação do DNA/efeitos dos fármacos , DNA de Neoplasias/efeitos dos fármacos , Células HeLa , Humanos , Marcação In Situ das Extremidades Cortadas , Microscopia Confocal , Microscopia Eletrônica de Transmissão , Microscopia de Fluorescência , Sais de Tetrazólio , Tiazóis
14.
Life Sci ; 76(18): 2115-24, 2005 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-15826878

RESUMO

Lycium barbarum polysaccharide (LBP), extracted from Lycium barbarum that is a kind of traditional Chinese herb, is found to have anticancer activity. In this study, the effect of LBP on the proliferation rate, cell cycle distribution and apoptosis in the human hepatoma QGY7703 cell line were investigated. The effects of this compound were also tested on the concentration of calcium in cells. LBP treatment caused inhibition of QGY7703 cell growth with cycle arrest in S phase and apoptosis induction. The amount of RNA in cells and the concentration of intracellular Ca2+ were increased. Moreover, the distribution of calcium in cells was changed. Taken together, the study suggests that the induction of cell cycle arrest and the increase of intracellular calcium in apoptotic system may participate in the antiproliferative activity of LBP in QGY7703 cells.


Assuntos
Antineoplásicos Fitogênicos/uso terapêutico , Apoptose , Carcinoma Hepatocelular/tratamento farmacológico , Medicamentos de Ervas Chinesas/uso terapêutico , Neoplasias Hepáticas/tratamento farmacológico , Lycium/química , Cálcio/metabolismo , Divisão Celular , Linhagem Celular Tumoral , Proliferação de Células , Hepatócitos/citologia , Humanos , Polissacarídeos/química , Polissacarídeos/uso terapêutico , RNA/análise
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