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1.
Int J Biol Macromol ; 253(Pt 2): 126730, 2023 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-37678699

RESUMO

Hydrogels are attractive materials with structures and functional properties similar to biological tissues and widely used in biomedical engineering. However, traditional synthetic hydrogels possess poor mechanical strength, and their applications are limited. Herein, a multidimensional material design method is developed; it includes the in situ gelation of silk fabric and nacre-inspired layer-by-layer assembly, which is used to prepare silk fibroin (SF) hydrogels. The in situ gelation method of silk fabric introduces a directionally ordered fabric network in a silk substrate, considerably enhancing the strength of hydrogels. Based on the nacre structure, the layer-by-layer assembly method enables silk hydrogels to break through the size limit and increase the thickness, realizing the longitudinal extension of the hydrogels. The application of the combined biomineralization and hot pressing method can effectively reduce interface defects and improve the interaction between organic and inorganic interfaces. The multidimensional material design method helps increase the strength (287.78 MPa), toughness (18.43 MJ m-3), and fracture energy (50.58 kJ m-2) of SF hydrogels; these hydrogels can weigh 2000 times their own weight. Therefore, SF hydrogels designed using the aforementioned combined method can realize the combination of strength and toughness and be used in biological tissue engineering and structural materials.


Assuntos
Fibroínas , Nácar , Fibroínas/química , Hidrogéis/química , Biomineralização , Nanopartículas em Multicamadas , Seda/química
2.
J Ethnopharmacol ; 314: 116566, 2023 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-37169317

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: The Chinese herbal prescription Yi-Fei San-Jie pill (YFSJ) has been used for adjuvant treatment in patients with lung cancer for a long time. AIM OF THE STUDY: Reports have indicated that the combination of gefitinib (Gef) with YFSJ inhibits the proliferation of EGFR-TKI-resistant cell lines by enhancing cellular apoptosis and autophagy in non-small cell lung cancer (NSCLC). However, the molecular mechanisms underlying the effect of YFSJ on EGFR-TKI resistance and related metabolic pathways remain to be explored. MATERIALS AND METHODS: In our report, ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS), metabolomics, network pharmacology, bioinformatics, and biological analysis methods were used to investigate the mechanism. RESULTS: The UPLC-MS/MS data identified 42 active compounds of YFSJ extracts. YFSJ extracts can enhance the antitumor efficacy of Gef without hepatic and renal toxicity in vivo. The analysis of the metabolomics pathway enrichment revealed that YFSJ mainly affected the tyrosine metabolism pathway in rat models. Moreover, YFSJ has been shown to reverse Gef resistance and improve the effects of Gef on the cellular viability, migration capacity, and cell cycle arrest of NSCLC cell lines with EGFR mutations. The results of network pharmacology and molecular docking analyses revealed that tyrosine metabolism-related active compounds of YFSJ affect EGFR-TKIs resistance in NSCLC by targeting cell cycle and the MET/EGFR signaling pathway; these findings were validated by western blotting and immunohistochemistry. CONCLUSIONS: YFSJ inhibits NSCLC by inducing cell cycle arrest in the G1/S phase to suppress tumor growth, cell viability, and cell migration through synergistic effects with Gef via the tyrosine metabolic pathway and the EGFR/MET signaling pathway. To summarize, the findings of the current study indicate that YFSJ is a prospective complementary treatment for Gef-resistant NSCLC.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Ratos , Animais , Carcinoma Pulmonar de Células não Pequenas/patologia , Gefitinibe/farmacologia , Gefitinibe/uso terapêutico , Neoplasias Pulmonares/patologia , Simulação de Acoplamento Molecular , Cromatografia Líquida , Estudos Prospectivos , Receptores ErbB/metabolismo , Resistencia a Medicamentos Antineoplásicos , Espectrometria de Massas em Tandem , Transdução de Sinais , Ciclo Celular , Linhagem Celular Tumoral , Inibidores de Proteínas Quinases/farmacologia , Proliferação de Células
3.
Int J Biol Macromol ; 242(Pt 2): 124912, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37207750

RESUMO

Flexible supercapacitors are an important portable energy storage but suffer from low capacitance, inability to stretch, etc. Therefore, flexible supercapacitors must achieve higher capacitance, energy density, and mechanical robustness to expand the applications. Herein, a hydrogel electrode with excellent mechanical strength was created by simulating the collagen fiber network and proteoglycan in cartilage using silk nanofiber (SNF) network and polyvinyl alcohol (PVA). The Young's modulus and breaking strength of the hydrogel electrode increased by 205 % and 91 % compared with PVA hydrogel owing to the enhanced effect of the bionic structure, respectively, which are 1.22 MPa and 1.3 MPa. The fracture energy and fatigue threshold reached 1813.5 J/m2 and 1585.2 J/m2, respectively. The SNF network effectively connected carbon nanotubes (CNTs) and polypyrrole (PPy) in series, affording a capacitance of 13.62 F/cm2 and energy density of 1.2098 mWh/cm2. This capacitance is the highest among currently reported PVA hydrogel capacitors, which can maintain >95.2 % after 3000 charge-discharge cycles. This capacitance Notably, the cartilage-like structure endowed the supercapacitor with high resilience; thus, the capacitance remained >92.1 % under 150 % deformation and >93.35 % after repeated stretching (3000 times), which was far superior to that of other PVA-based supercapacitors. Overall, this effective bionic strategy can endow supercapacitors with ultrahigh capacitance and effectively ensure the mechanical reliability of flexible supercapacitors, which will help expand the applications of supercapacitors.


Assuntos
Nanofibras , Nanotubos de Carbono , Hidrogéis , Polímeros , Reprodutibilidade dos Testes , Pirróis
4.
Int J Biol Macromol ; 225: 1361-1373, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36435456

RESUMO

Cellulose sponges with compressibility and resilience are an ideal packaging material for fruits with fragile skin. Here, a soft and elastic all-cellulose sponge (CS) with a hierarchical cellular structure was fabricated, where the long molecular chain cellulose constructed major pores, the cellulose at nanoscale acted as an elastic nanofiller to fill the gaps of long molecular chain cellulose fibers and constructed minor pores. With these two kinds of pores, this structure can absorb strain hierarchically. The sponge can protect fruits from mechanical damage when dropped or repeated vibration. Furthermore, the CS modified with chlorogenic acid (C-CGAS) had excellent antibacterial and antifungal abilities. Therefore, C-CGAS could extend the storage time of strawberries to 18 days without any microbial invasion, which is the longest storage time reported thus far. This study provides a new idea for the preparation of polymer sponges and a new design for the development of antimicrobial packaging materials.


Assuntos
Celulose , Frutas , Celulose/química , Antibacterianos/farmacologia , Antibacterianos/química , Vagina , Nucleotidiltransferases
5.
Front Genet ; 13: 982030, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36226174

RESUMO

Background: The function and features of long non-coding RNAs (lncRNAs) are already attracting attention and extensive research on their role as biomarkers of prediction in lung cancer. However, the signatures that are both related to genomic instability (GI) and tumor immune microenvironment (TIME) have not yet been fully explored in previous studies of non-small cell lung cancer (NSCLC). Method: The clinical characteristics, RNA expression profiles, and somatic mutation information of patients in this study came from The Cancer Genome Atlas (TCGA) database. Cox proportional hazards regression analysis was performed to construct genomic instability-related lncRNA signature (GIrLncSig). Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses were performed to predict the potential functions of lncRNAs. CIBERSORT was used to calculate the proportion of immune cells in NSCLC. Result: Eleven genomic instability-related lncRNAs in NSCLC were identified, then we established a prognostic model with the GIrLncSig ground on the 11 lncRNAs. Through the computed GIrLncSig risk score, patients were divided into high-risk and low-risk groups. By plotting ROC curves, we found that patients in the low-risk group in the test set and TCGA set had longer overall survival than those in the high-risk group, thus validating the survival predictive power of GIrLncSig. By stratified analysis, there was still a significant difference in overall survival between high and low risk groups of patients after adjusting for other clinical characteristics, suggesting the prognostic significance of GIrLncSig is independent. In addition, combining GIrLncSig with TP53 could better predict clinical outcomes. Besides, the immune microenvironment differed significantly between the high-risk and the low-risk groups, patients with low risk scores tend to have upregulation of immune checkpoints and chemokines. Finally, we found that high-risk scores were associated with increased sensitivity to chemotherapy. Conclusion: we provided a new perspective on lncRNAs related to GI and TIME and revealed the worth of them in immune infiltration and immunotherapeutic response. Besides, we found that the expression of AC027288.1 is associated with PD-1 expression, which may be a potential prognostic marker in immune checkpoint inhibitor response to improve the prediction of clinical survival in NSCLC patients.

6.
Carbohydr Polym ; 296: 119962, 2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-36088016

RESUMO

Disinfecting microbially contaminated water in a safe and sustainable way is a great challenge. The phenolics and flavonoids in plants are ideal antibacterial agents for biosafety. Herein, an all-plant-derived antibacterial sponge with a hierarchical cellular structure was prepared from natural phenolic and flavonoid crude extracts and cellulose for water purification. After being modified by quercetin, the quercetin-cellulose sponge (Q-CS) exhibits great toughness, elasticity and a large specific surface area, which benefited from a unique hierarchical cellular structure. Q-CS shows ultrahigh water flux (4.5 × 105 L·m-2·h-1·bar-1) and excellent antibacterial abilities against Escherichia coli and Staphylococcus aureus (<1.87 % viability). Sponges modified with crude pyrola (P-CS) and mulberry leaf extracts (M-CS) have similar properties compared with Q-CS. The good performances of P-CS and M-CS show the strong antibacterial applications of natural crude extract. This work provides a strategy for fabricating sustainable and safe antibacterial sponges for water disinfection.


Assuntos
Celulose , Desinfecção , Antibacterianos/química , Antibacterianos/farmacologia , Celulose/química , Celulose/farmacologia , Escherichia coli , Flavonoides/farmacologia , Fenóis/farmacologia , Quercetina , Água/química
8.
Molecules ; 27(9)2022 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-35566039

RESUMO

Mulberry (Morus alba L.) fruit is a fruit with nutritional and medicinal value. It is widely cultivated in different regions of China, which may result in differences in its chemical composition. In this research, 25 mulberry fruit samples from six provinces in China were investigated. The contents of anthocyanins were evaluated by high-performance liquid chromatography (HPLC). The contents of two main anthocyanins, cyanidin-3-O-glucoside (C3G) and cyanidin-3-O-rutinoside (C3R), ranged from 0.656 ± 0.006 mg/g to 4.367 ± 0.243 mg/g and from 0.226 ± 0.007 mg/g to 1.649 ± 0.013 mg/g, respectively. Additionally, the contents of total phenolic, total flavonoid, vitamin C, titratable acids, reducing sugars and antioxidant capacity (FRAP, DPPH, scavenging and hydroxyl radical scavenging activity) were also assessed. The results and principal component analysis showed that the Zhongsang 5801 variety from Sichuan, Dechang had the greatest health value with the highest active compound contents. Based on our analysis, the variety from Sichuan, Dechang is a high-quality plant source for mulberry fruit cultivation. This research provides a basis for the rational development and utilization of mulberry fruit resources in China.


Assuntos
Antocianinas , Morus , Antocianinas/química , Antioxidantes/química , Frutas/química , Morus/química , Extratos Vegetais/química
9.
Int J Biol Macromol ; 211: 470-480, 2022 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-35577198

RESUMO

Strawberry is a nutritious food that is susceptible to mechanical injury and microbiological infection. Traditional coatings for strawberry packaging provide resistance against microbial infection but not against mechanical damage. In this study, a soft and elastic cellulose sponge modified with silver nanoparticles (AgNPs@CS-1:1) was prepared as strawberry packaging material, and it provided effective protection against mechanical damage. In addition, after 1000 cyclic compression, AgNPs@CS-1:1 presented only 16.80% unrecoverable deformation and still had elasticity, suggesting its fatigue resistance and durable protection for strawberry against damage caused by repeated vibrations during transportation. In addition, AgNPs@CS-1:1 had good antibacterial (E. coli and S. aureus) and antifungal (Rhizopus stolonifer) abilities. The storage time of strawberries packaged by AgNPs@CS-1:1 was extended to 12 days without microbial invasion. Thus, AgNPs@CS-1:1 provided dual protection at the physical and microbial levels. This study proposes a new method for the preservation of strawberries based on the utilization of cellulose.


Assuntos
Fragaria , Nanopartículas Metálicas , Antibacterianos/farmacologia , Celulose/farmacologia , Escherichia coli , Testes de Sensibilidade Microbiana , Prata/farmacologia , Staphylococcus aureus
10.
Carbohydr Polym ; 247: 116569, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-32829785

RESUMO

In this study, a simple and environmentally friendly method was developed for synthesizing 3D porous cellulose supported palladium nanoparticles (PdNPs) catalysts. PdNPs (3.1 ± 1.4 nm) can be synthesized directly by cellulose solution through microwave heating (60 °C, 4 h) and prepared into microspheres by freeze-drying to degrade methylene blue (MB) and Congo red (CR) rapidly. In addition, the reduction ability of cellulose hydroxyl group was proved by XPS and FTIR results. And the contact angle of 38.20° proves its hydrophilic ability. Cellulose-PdNPs microspheres showed high catalytic efficiency achieved 99 % and after multiple cycles it was still higher than 90 %. Therefore, the method proposed in this paper provides some new applications for cellulose, and the cellulose-Pd catalysts prepared by the research also have potential application value in the field of environment.


Assuntos
Celulose/química , Corantes/química , Nanopartículas Metálicas/química , Microesferas , Micro-Ondas , Paládio/química , Catálise , Cor
11.
PLoS One ; 13(6): e0198072, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29944667

RESUMO

Guangdong, Guangxi and Chongqing are emerging sericulture areas in China where the production of mulberry leaves is huge. In order to identity high quality mulberry leaves that are suitable for healthy products to expand planting, 24 samples from three regions (Guangdong, Guangxi, Chongqing) in the south of China were quantified for two alkaloids (1-deoxynojirimycin and fagomine) and five phenols (chlorogenic acid, rutin, isoquercitrin, etc.) using high-performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS). Additionally, the total phenolic and total flavonoid contents, antioxidant and glycosidase inhibitory activities (hypoglycemic activity) were tested using different assays (DPPH, ABTS, FRAP) to comprehensively evaluate the quality of the mulberry leaves. The contents of DNJ and fagomine ranged from 0.401±0.003 to 5.309±0.036 mg/g and from 0.279±0.031 to 2.300±0.060 mg/g, respectively. The main phenolic constituents were chlorogenic acid, rutin and isoquercitrin, with chlorogenic acid present in the highest concentrations, ranging from 3.104±0.191 to 10.050±0.143 mg/g. The antioxidant activity exhibited a tendency as follows: Guangxi > Guangdong > Chongqing, except for two samples from Chongqing, which showed the highest antioxidant activity. Based on our study, mulberry leaves from Guangdong and Guangxi could be future sources of natural hypoglycemic and antioxidant products.


Assuntos
Antioxidantes/química , Hipoglicemiantes/química , Morus/química , Morus/crescimento & desenvolvimento , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Folhas de Planta/química , Alcaloides/análise , Antioxidantes/farmacologia , China , Indústria Alimentícia , Inibidores de Glicosídeo Hidrolases/química , Inibidores de Glicosídeo Hidrolases/farmacologia , Hipoglicemiantes/farmacologia , Fenóis/análise
12.
Artigo em Inglês | MEDLINE | ID: mdl-29885513

RESUMO

Flos Lonicerae was an important Chinese medicine. In this research, a microwave assisted extraction method was applied for the extraction of chlorogenic acid from Flos Lonicerae. The operating conditions were optimized using a Box-Behnken design test. Under the optimal conditions, the extraction yield of chlorogenic acid reached 32.52 ±â€¯1.31 mg/g. Next, a direct analysis in real time mass spectrometry (DART-MS) method was utilized to quantify of chlorogenic acid in Flos Lonicerae extracts. The primary parameters were optimized to obtain maximum signal intensity. In the detection process of the actual samples, the results obtained by DART-MS are consistent with those obtained by HPLC method with short detection time and acceptable repeatability and precision (<15%). In addition, the DART-MS/MS method has several advantages, such as speed, low cost and simplicity. Therefore, the DART-MS method is an efficient method that can be applied in the quantification of chlorogenic acid in Flos Lonicerae.


Assuntos
Ácido Clorogênico/análise , Extratos Vegetais/química , Espectrometria de Massas em Tandem/métodos , Caprifoliaceae/química , Ácido Clorogênico/química , Ácido Clorogênico/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Limite de Detecção , Modelos Lineares , Lonicera , Micro-Ondas , Reprodutibilidade dos Testes
13.
Carbohydr Polym ; 181: 560-569, 2018 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-29254008

RESUMO

In the present study, porous magnetic cellulose beads (CBs) were prepared and further modified using amines. The CBs appeared to have good spherical shape and three-dimensional (3D) porous structure. In the adsorption tests, the modified cellulose beads (MCBs) showed better adsorption capacities and shorter adsorption times on hyperin and 2'-O-galloylhyperin than the commercial resins. The adsorption may be due to the hydrogen bonding between the target compounds and the amine groups of MCBs. After adsorption and desorption, the contents of hyperin and 2'-O-galloylhyperin reached 1.32% and 3.92%, which were 4.08 and 4.23 times higher than those in the Pyrola extracts. Therefore, the prepared MCBs in this study make an excellent adsorbing material of hyperin and 2'-O-galloylhyperin, and it may have potential for the separation of other natural compounds.

14.
Int J Biol Macromol ; 102: 1066-1072, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28478052

RESUMO

In this work, a novel and sustainable biosorbent, regenerated silk fibroin film (rSFF) was successfully prepared and its adsorbability to azo dyes (acid yellow 11, naphthol orange and direct orange S) was measured. At optimal conditions, the adsorption capacity of rSFF for acid yellow 11 reached up to 59.71mg/g, which was 1.23-fold higher than that of raw silk fibroin fibers. More importantly, rSFF exhibited a high level of flexibility and functionality as well as a good shaping ability, which were crucial for its practical application. The SEM results showed that rSFF was a porous material, indicating that it had more available adsorption sites compared with raw silk fibroin fibers, which might contribute to the higher adsorption capacity of rSFF. Isotherm equilibrium studies revealed that the azo dye adsorption process followed the Langmuir model, indicating that rSFF was a structurally homogenous adsorbent. The recycle test showed that rSFF had potential to be reused in a number of treatment cycles. After five cycles, its adsorbability to acid yellow 11 remained as high as 47.20mg/g. Finally, a scale-up experiment was performed for rSFF, and the results indicated that it was feasible for rSFF to extend the practical application.


Assuntos
Compostos Azo/química , Fibroínas/química , Poluentes Químicos da Água/química , Adsorção , Compostos Azo/isolamento & purificação , Poluentes Químicos da Água/isolamento & purificação
15.
Carbohydr Polym ; 137: 473-479, 2016 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-26686153

RESUMO

A Box-Behnken design (BBD) was applied to optimize the ultrasound-assisted extraction of polysaccharides from mulberry leaves. Under the optimum conditions of an extraction temperature of 57 °C, an extraction time of 80 min and a liquid/solid ratio of 53 mL/g, the mulberry leaf polysaccharide (MLP) yield was 6.92 ± 0.29%. Then, three fractions of MLPs were obtained by deproteinization, dialysis and decolorization. The carbohydrate content, FT-IR spectrum and monosaccharide composition of the MLPs were also investigated. The antioxidant activities of the three fractions were compared, and the results indicated that the antioxidant activities decreased with the increasing MLP purity. Therefore, highly concentrated MLPs were shown to have very little antioxidant activity. After quercetin (10 µg/mL) was added, the antioxidant activities were improved significantly. This result showed that MLPs and quercetin have a synergistic effect on the antioxidant activity. Although the MLPs have very little antioxidant activity alone, they greatly enhance the antioxidant activity of flavonoids. Thus, MLPs can be used as an antioxidant activity enhancer in the food industry.


Assuntos
Antioxidantes/química , Morus/química , Extratos Vegetais/química , Polissacarídeos/química , Antioxidantes/farmacologia , Fracionamento Químico/métodos , Flavonoides/química , Flavonoides/farmacologia , Extratos Vegetais/farmacologia , Folhas de Planta/química , Polissacarídeos/farmacologia , Sonicação/métodos
16.
Food Funct ; 6(10): 3323-33, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26256648

RESUMO

A novel extraction method, homogenate-assisted negative pressure cavitation extraction (HNPCE), was designed for the extraction and determination of the main phenolic compounds of Pyrola incarnata Fisch. by LC-MS/MS. The particle sizes and extraction yields in the process of homogenization were compared with conventional pulverization. The results showed that homogenization for less than 120 s could produce more suitable particle size powders for analyte extraction. The following NPCE parameters were optimized by a BBD test and under the optimal conditions, the maximum extraction yields of arbutin, epicatechin, hyperin, 2'-O-galloylhyperin and chimaphilin increased by 68.7%, 72.0%, 43.3%, 62.5% and 34.5% with respect to normal NPCE. The LC-MS/MS method was successfully applied for the quantification of five target compounds in pyrola, and the results of the precision test indicated a high accuracy of the present method for the quantification of the target compounds in pyrola. Furthermore, the antioxidant activities of the pyrola extracts were also determined. The results showed that pyrola had good antioxidant activities and it was a valuable antioxidant natural source.


Assuntos
Cromatografia Líquida , Fenóis/análise , Extratos Vegetais/análise , Pyrola/química , Espectrometria de Massas em Tandem , Antioxidantes/análise , Arbutina/análise , Catequina/análise , Ácido Gálico/análogos & derivados , Ácido Gálico/análise , Naftoquinonas/análise , Quercetina/análogos & derivados , Quercetina/análise , Reprodutibilidade dos Testes
17.
Food Chem ; 169: 270-6, 2015 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-25236226

RESUMO

A novel and effective extraction method, namely negative pressure cavitation-microwave assisted extraction technique (NMAE), was developed for the preparation of extracts of Pyrola incarnata Fisch., which are rich in the main constituents hyperin, 2'-O-galloylhyperin and chimaphilin. Single factor experiments and Box-Behnken design (BBD) were combined with a response surface methodology to examine factors affecting extraction. Maximum extraction yields of hyperin, 2'-O-galloylhyperin and chimaphilin (1.339±0.029, 4.831±0.117 and 0.329±0.011mg/g, respectively) were achieved under the following optimised conditions: 700W microwave power, 50°C extraction temperature, 30:1mL/g liquid-solid ratio, -0.05MPa negative pressure, 55% ethanol concentration and 12min extraction time. First-order kinetics equation demonstrated that NMAE offered significant savings in extraction time, and enhancing extraction efficiency. Furthermore, NMAE extracts yielded excellent antioxidant activity (IC50 0.121mg/mL for DPPH 2.896mmol FeSO4/g DW FRAP).


Assuntos
Antioxidantes/farmacologia , Ácido Gálico/análogos & derivados , Naftoquinonas/análise , Extratos Vegetais/farmacologia , Pyrola/química , Quercetina/análogos & derivados , Ácido Gálico/análise , Micro-Ondas , Pressão , Quercetina/análise
18.
Food Chem Toxicol ; 70: 1-8, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24793375

RESUMO

Chimaphilin, 2,7-dimethyl-1,4-naphthoquinone, is extracted from pyrola [Passiflora incarnata Fisch.]. In this study, the anticancer activity and underlying mechanisms of chimaphilin toward human breast cancer MCF-7 cells are firstly investigated. Chimaphilin could inhibit the viability of MCF-7 cells in a concentration-dependent manner, and the IC50 value was 43.30µM for 24h. Chimaphilin markedly induced apoptosis through the investigation of characteristic apoptotic morphological changes, nuclear DNA fragmentation, annexin V-FITC/propidium iodide (PI) double staining. Flow cytometry assay revealed that chimaphilin triggered a significant generation of ROS and disruption of mitochondrial membrane potential. Additionally, western blotting assay showed that chimaphilin suppressed Bcl-2 level and enhanced Bad level, then activated caspase-9 and caspase-3, and further activated the poly ADP-ribose polymerase (PARP), finally induced cell apoptosis involving the mitochondrial pathway. Furthermore, free radical scavengers N-acetyl-L-cysteine (NAC) pretreatment test testified that chimaphilin could increase the generation of ROS, then induce cell apoptosis. In general, the present results demonstrated that chimaphilin induced apoptosis in human breast cancer MCF-7 cells via a ROS-mediated mitochondrial pathway.


Assuntos
Apoptose/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Naftoquinonas/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Acetilcisteína/farmacologia , Anexina A5/metabolismo , Caspase 3/genética , Caspase 3/metabolismo , Caspase 9/genética , Caspase 9/metabolismo , Proliferação de Células/efeitos dos fármacos , Fragmentação do DNA/efeitos dos fármacos , Fluoresceína-5-Isotiocianato/análogos & derivados , Fluoresceína-5-Isotiocianato/metabolismo , Humanos , Concentração Inibidora 50 , Células MCF-7 , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias/metabolismo , Passiflora/química , Propídio/metabolismo , Proteína X Associada a bcl-2/genética , Proteína X Associada a bcl-2/metabolismo , Proteína de Morte Celular Associada a bcl/genética , Proteína de Morte Celular Associada a bcl/metabolismo
19.
Food Chem ; 141(3): 2213-9, 2013 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-23870950

RESUMO

The variation of antioxidant activity and active components in pyrola [Passiflora incarnata Fisch.] from eight sites in Northeast China were investigated. Total phenolic and flavonoid contents were determined and varied within the range of 39.66-181.48 mg/g and 2.47-22.11 mg/g, respectively. Antioxidant activities were determined by scavenging activity against DPPH and ABTS, by a reducing power test and by a ß-carotene-linoleic acid bleaching test. The IC50 of Tahe samples determined by the DPPH test was 0.106±0.006 mg/mL which was very close to that of Vc (0.076±0.004 mg/mL). The Tahe samples had good antioxidant activity. Principal component activity analysis indicated that the Tahe samples of P. incarnata had the highest potential antioxidant properties, and may be a valuable antioxidant natural resource in the northeast of China.


Assuntos
Antioxidantes/análise , Flavonoides/análise , Passiflora/química , Extratos Vegetais/análise , China , Geografia , Passiflora/classificação , Fenóis/análise
20.
Analyst ; 138(16): 4631-41, 2013 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-23762895

RESUMO

A novel negative pressure and microwave assisted extraction technique (NMAE) was first proposed and applied for extraction of phenolic compounds from pyrola. [C4MIM]BF4 aqueous solution was selected as extraction solvent. Optimal extraction conditions were microwave power 700 W, negative pressure -0.07 MPa, temperature 40 °C, liquid-solid ratio 20 : 1, ionic liquid (IL) concentration 0.5 M, extraction time 15 min. The predominance of NMAE was investigated by comparing with microwave-assisted extraction (MAE) and negative pressure cavitation extraction (NPCE) using a first-order kinetics equation. The C∞ values of the target compounds by NMAE were from 0.406 to 5.977 mg g⁻¹ higher than these by MAE and NPCE, which indicated that NMAE had higher extraction yields. The K values of NMAE were also the highest; it was testified that the target compounds could be transferred from matrix into solvent much more effectively by NMAE than by MAE and NPCE. In addition, the NMAE method was validated in terms of repeatability and reproducibility, the relative standard deviation for relative recovery was lower than 5.43 and 8.78%, respectively. Therefore, NMAE was a developed extraction technique for analytical sample preparation. The RP-HPLC-UV method was also successfully applied for the quantification of six target compounds in pyrola.


Assuntos
Extração Líquido-Líquido/métodos , Micro-Ondas , Fenóis/análise , Extratos Vegetais/análise , Pyrola/química , Cromatografia Líquida de Alta Pressão/métodos , Pressão
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