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1.
Front Microbiol ; 14: 1190624, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37415810

RESUMO

The dried tuber of Alisma orientale (Sam.) Juzep. (AOJ) is a traditional Chinese medicine with high medicinal value. The endophytic fungi of medicinal plants are a treasure house of natural compounds. However, there is a lack of research on the diversity and biological activity of endophytic fungi of AOJ. In this study, high-throughput sequencing technology was used to study the diversity of endophytic fungi in the roots and stems of AOJ, and endophytic fungi with a high output of phenols and flavonoids were screened by chromogenic reaction, and the antioxidant and antibacterial activities and chemical constituents of crude extracts of their fermentation broth were studied. A total of 3,426 amplicon sequence variants (ASVs) belonging to 9 phyla, 27 classes, 64 orders, 152 families, and 277 genera were identified from AOJ. There were significant differences in the endophytic fungal communities of AOJ roots and stems, as well as in the endophytic fungal communities of triangular AOJ and circular AOJ. In addition, 31 strains of endophytic fungi were isolated from AOJ, of which 6 strains had good antioxidant and antibacterial activities. The crude extract of YG-2 had the strongest free radical scavenging ability and bacteriostatic ability, and its IC50 DPPH, IC50 ABTS, and IC50⋅OH values were 0.009 ± 0.000 mg/mL, 0.023 ± 0.002 mg/mL, and 0.081 ± 0.006 mg/mL, respectively. The results of LC-MS showed that the main component of the crude extract of YG-2 was caffeic acid (10.12 µmol/g). Overall, the results of this study preliminarily elucidated the diversity and community composition of endophytic fungi of AOJ, indicating that AOJ endophytic fungi have abundant secondary metabolites and good antioxidant and antibacterial activities. This study provides an important reference for further research, development and utilization of AOJ endophytic fungi and a theoretical basis for the further development of the endophytic fungus YG-2 (Chaetomium globosum) as a source of antioxidants.

2.
Int J Biol Macromol ; 240: 124377, 2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-37044322

RESUMO

In this study, EPS-Fe(III) complexes were synthesized, and their structural characteristics, thermal stability, antioxidant activity and digestive properties were evaluated. The content of iron in the EPS-Fe(III) complex was 6.34 ± 1.43 %. The absorbance bands of EPS and EPS-Fe(III) complexes were easily changed, indicating that iron ions can interact with the hydroxyl or carboxyl groups of EPS. Energy spectrometric analysis showed that a strong iron signal was observed in the EPS-Fe(III) complex. The IC50 values of the EPS-Fe(III) complex for DPPH, hydroxyl radical and ABTS were 1.52 mg/mL, 2.63 mg/mL and 1.20 mg/mL, respectively. Under oxidative stress, EPS-Fe(III) can prolong the lifespan of nematodes through the DAF-16 and SKN-1 pathways. Under the condition of gastric juice and intestinal juice, the iron content released from artificial intestinal juice reached 66 %. In addition, the negative effect of trypsin or polyphenols on the solubility of iron in EPS-Fe(III) digestive solution was lower than that in ferric chloride digestive solution. In conclusion, the EPS-Fe(III) complex can be used as a new type of iron supplement, which has good antioxidant activity, high stability and good water solubility.


Assuntos
Cordyceps , Ferro , Ferro/metabolismo , Compostos Férricos/química , Antioxidantes/farmacologia , Cordyceps/química
3.
Front Pharmacol ; 13: 1049890, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36386171

RESUMO

Ligusticum chuanxiong Hort. (CX) is a medicinal and edible plant including a variety of active substances, which may be an available resource for the treatment of related diseases. To expand the medicinal uses of CX, this study aims to explore the antioxidant, anti-aging and neuroprotective effects of the Ligusticum chuanxiong leaves (CXL) and rhizome (CXR) extracts. We first characterize CX phytochemical spectrum by LC-MS as well as antioxidant capacity. Acute toxicity, anti-oxidative stress capacity, lifespan and healthspan was evaluated in C elegans N2. Neuroprotective effect was evaluated in vitro and in vivo (C elegans CL4176 and CL2355). In this study, we detected 74 and 78 compounds from CXR and CXL, respectively, including phthalides, alkaloids, organic acids, terpenes, polyphenols and others. Furthermore, we found that CXs not only protect against oxidative stress, but also prolong the lifespan, alleviate lipofuscin, malondialdehyde (MDA) and reactive oxygen species (ROS) accumulation, and improve movement level, antioxidant enzyme activity in C elegans N2. However, only CXR reduced the ß-amyloid peptide (Aß)-induced paralysis phenotype in CL4176s and alleviated chemosensory behavior dysfunction in CL2355s. In addition, CXR treatment reduced the production of Aß and ROS, enhanced SOD activity in CL4176s. The possible mechanism of anti-aging of CXL and CXR is to promote the expression of related antioxidant pathway genes, increase the activity of antioxidant enzymes, and reduce the accumulation of ROS, which is dependent on DAF-16 and HSF-1 (only in CXR). CXR was able to activate antioxidase-related (sod-3 and sod-5) and heat shock protein genes (hsp-16.1 and hsp-70) expression, consequently ameliorating proteotoxicity related to Aß aggregation. In summary, these findings demonstrate the antioxidant, anti-aging and neuroprotective (only in CXR) activities of the CX, which provide an important pharmacological basis for developing functional foods and drugs to relieve the symptoms of aging and AD. However, the material basis of neuroprotective activity and antiaging effects need to be elucidated, and the relationship between these activities should also be clarified in future studies.

4.
Front Pharmacol ; 13: 983716, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36110524

RESUMO

The chemical composition and antioxidant activity of extracts (POE) of Penicillium oxalate isolated from Ligusticum chuanxiong Hort have been investigated. However, the biological activity of POE is limited, and its antioxidant, stress resistance and DNA protection effects in vivo are unclear. The current study aims to explore the beneficial effects of POE on DNA damage protection in pBR322 plasmid and lymphocytes and stress resistance in Caenorhabditis elegans. The results showed that POE increased the survival rate of C. elegans under 35°C, UV and H2O2 stress, attenuated ROS and MDA accumulation, and enhanced the activity of some important enzymes (SOD, CTA, and GSH-PX). In addition, the POE-mediated stress resistance involved the upregulation of the expression of the sod-3, sod-5, gst-4, ctl-1, ctl-2, daf-16, hsp-16.1, hsp-16.2, and hsf-1 genes and acted dependently on daf-16 and hsf-1 rather than skn-1. Moreover, POE also reduced lipofuscin levels, but did not prolong the lifespan or damage the growth, reproduction and locomotion of C. elegans. Furthermore, POE showed a protective effect against DNA scission in the pBR322 plasmid and lymphocytes. These results suggested that P. oxalate extracts have significant anti-stress and DNA protection potential and could be potential drug candidates in the pharmaceutical field, thus greatly broadening the understanding of the biological effects of the endophytic fungus P. oxalate.

5.
Front Nutr ; 9: 911310, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35757258

RESUMO

The polysaccharides from C. cicadae were extracted by ultrasonically-assisted enzymatic extraction (UAEE). Response surface analysis was used to determine the optimum parameters as follows: addition of enzymes, 0.71%; extraction temperature, 60°C; extraction time, 18 min; liquid-solid ratio, 46:1 (mL/g). The extraction yield of polysaccharide was 3.66 ± 0.87%. A novel polysaccharide fraction (JCH-a1) from C. cicadae was extracted and then purified by cellulose DEAE-32 and Sephadex G-100 anion exchange chromatography. The analysis results showed that the molar ratio of galactose, glucose, and mannose in JCH-a1 cells (60.7 kDa) was 0.89:1:0.39. JCH-a1 with a triple helix contains more α-glycosides and has strong thermal stability. Moreover, JCH-a1 showed strong antioxidant activity and acted as a strong inhibitor of α-glucosidase in vitro. In addition, JCH-a1 can prolong the lifespan of C. elegans. The present study might provide a basis for further study of JCH-a1 as an antioxidant and hypoglycemic food or drug.

6.
J Biomol Struct Dyn ; 40(16): 7584-7597, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-33734039

RESUMO

The FGF/FGFR system may affect tumor cells and stromal microenvironment through autocrine and paracrine stimulation, thereby significantly promoting oncogene transformation and tumor growth. Abnormal expression of FGFR1 in cells is considered to be the main cause of tumorigenesis and a potential target for the treatment of cancer. In this study, a combination of structure-based drug carriers and molecular docking-based virtual screening was used to screen new potential FGFR1 inhibitors. Forty eight known inhibitors were collected to establish 3 D-QSAR models and pharmacophore models, investigate the relationship between the activity and conformation of compounds, and verify the efficiency of pharmacophore. In Accelrys Discovery Studio 2016, the ZINC database was filtered by Lipinski's Rule of Five and SMART's filtration. Then, Hypo01 was used for virtual screening of ZINC database. Compounds with predicted activity values less than 1 µM were molecularly docked with FGFR1 protein crystals, the docking results were observed, and the interaction between compounds and targets was studied. The absorption, distribution, metabolism and excretion (ADME) and toxicity of potential inhibitors were studied, and a compound with new structural scaffolds were obtained. It could be further studied to explore their better therapeutic effects. Communicated by Ramaswamy H. Sarma.


Assuntos
Relação Quantitativa Estrutura-Atividade , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos , Ligantes , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Zinco
7.
Front Nutr ; 9: 1052818, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36704792

RESUMO

The research on the development of dragon fruit and kiwi fruit through LAB-yeast compound fermentation is very limited, and there are few related fermentation products on the market. The purpose of this study was to evaluate the stability of the antioxidant capacity of fermented beverages (FB) through in vitro simulated digestion, to evaluate the changes in metabolites of juice after fermentation through untargeted metabolomics, and used Caenorhabditis elegans as a model to evaluate its anti-aging activity. The results showed that FB not only has good in vitro antioxidant activity, but also the total phenol content (TPC), total flavonoid content (TFC), ABTS scavenging ability, and hydroxyl radical scavenging ability of FB were significantly increased during gastric digestion and intestinal digestion. Metabolomics showed that the contents of phenols and flavonoids related to antioxidant increased after fermentation, and fermentation had a significant effect on organic acids and amino acids in FB. Finally, compared with the control group, although the original concentration of FB has a side-toxic effect on nematodes, the mean lifespan of C. elegans fed with 1.56% FB increased by 18.01%, SOD activity significantly increased by 96.16% and MDA content significantly decreased by 40.62%. FB has good antioxidant activity in vitro and in vivo, and the antioxidant activity is stable during the simulated digestion process.

8.
Front Microbiol ; 12: 771000, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34867905

RESUMO

The objective of this study was to evaluate the diversity of endophytic fungi of different parts of Ligusticum chuanxiong Hort (CX) and further characterize their biological activities and identify chemical compounds produced by these endophytic fungi. A total of 21 endophytic fungi were isolated and identified from CX. Penicillium oxalicum, Simplicillium sp., and Colletotrichum sp. were identified as promising strains by the color reaction. Comparing different organic extracts of the three strains, it was observed that the ethyl acetate extract of Penicillium oxalicum and Simplicillium sp. and the n-butanol extract of Colletotrichum sp. showed significant antioxidant and antibacterial activities. The ethyl acetate extracts of Penicillium oxalicum had outstanding antioxidant and antibacterial effects, and its radical scavenging rates for ABTS and DPPH were 98.43 ± 0.006% and 90.11 ± 0.032%, respectively. At the same time, their IC50 values were only 0.18 ± 0.02 mg/mL and 0.04 ± 0.003 mg/mL. The ethyl acetate extract of Penicillium oxalicum showed MIC value of only 0.5 mg/mL against Escherichia coli and Staphylococcus aureus. By liquid chromatography-mass spectrometry (LC-MS), we found that Penicillium oxalicum could produce many high-value polyphenols, such as hesperidin (36.06 µmol/g), ferulic acid (1.17 µmol/g), and alternariol (12.64 µmol/g), which can be a potential resource for the pharmaceutical industry. In conclusion, these results increase the diversity of CX endophytic fungi and the antioxidant and antibacterial activities of their secondary metabolites.

9.
J Healthc Eng ; 2021: 3531199, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34621501

RESUMO

Background: This study aims to analyze the influence of different dexmedetomidine doses on cognitive function. It works on early periods of patients undergoing laparoscopic extensive total hysterectomy. Method: 119 patients with gynecological cancer underwent a laparoscopic extensive total hysterectomy. The operation was performed at the Affiliated Women's and Children's Hospital of Xiamen University from January 2019 to June 2020. The score of MoCA and the level of TNF-α, IL-6, S-100ß protein, NSE, and GFAP of each group were compared 1 day before and after operation and 3 and 7 days after operation. Result: In four groups, remifentanil, sufentanil, and propofol were given in the following order: group A > group D > group C > group B. Group A > group D > group C in terms of time spent in the recovery room, extubation, and recovery from anesthesia. The difference between groups B and C was not significant (P > 0.05). Compared with group A, group B scored higher in MoCA at 1 day (T1), 3 days (T2), and 7 days (T3) after operation (P < 0.05). At the same scoring point, the score was group B > group C > group D > group A. The POCD of four groups all occurred at 3 days after surgery. Compared with the T0 point, the level of TNF-α and IL-6 of the four groups at T1 and T2 was significantly increased (P < 0.05). At T3, the level of TNF-α and IL-6 gradually decreased. At various periods, the levels of S-100 protein, NSE, and GFAP in groups B, C, and D were lower than those in group A (P0.05). Group B had a substantially higher rate of bradycardia than the other three groups (P0.05). The incidence of chills, respiratory depression, and restlessness in group A differed significantly from the other three groups (P < 0.05). Conclusion: Using 0.5 µg/kg dexmedetomidine during the perianaesthesia can effectively reduce anesthetic drugs in patients. They had a laparoscopic extensive complete hysterectomy, which helps to reduce the adverse responses and the occurrence of POCD while also protecting brain function.


Assuntos
Dexmedetomidina , Laparoscopia , Propofol , Criança , Cognição , Feminino , Humanos , Histerectomia
10.
PeerJ ; 9: e11974, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34513326

RESUMO

BACKGROUND: Functional fermented beverages are popular worldwide due to their potential to promote health. Starter culture is the main determinant of the final quality and flavor of fermented beverages. The co-cultivation of lactic acid bacteria (LAB) and yeast makes a significant contribution to the safe flavor of fermented beverages. However, the research on the potential of antioxidant, antimicrobial, and anti-biofilm formation of strawberry fermented beverage obtained by combining the LAB and yeast as starter cultures has not been well explored. METHODS: In this study, LAB and yeast were combined as starter culture to obtain strawberry fermented beverage. Fourier transform infrared (FTIR ) spectroscopy was used for the qualitative analysis of the fresh strawberry juice and fermented beverage. From the changes in antioxidant content, free radical scavenging ability, total superoxide dismutase (T-SOD) activity and total antioxidant capacity (T-AOC) to evaluate the antioxidant capacity of fermented beverage in vitro. The antibacterial ability was tested by the Oxford cup method. The biofilms of Escherichia coli ATCC 25922, Staphylococcus aureus ATCC 6538 under fermented beverages treatment was observed by Fluorescence microscope. In addition, sensory analysis was conducted in this study. RESULTS: In this study, the absorption peaks of Fourier transform infrared between 1,542 cm-1 and 976 cm-1, suggest the existence of organic acids, sugars and ethanol. The total phenols and total flavonoids content decreased by 91.1% and 97.5%, respectively. T-SOD activity increased by 33.33%.The scavenging ability of fermented beverage on superoxide anion free radicals was enhanced, and the scavenging ability on DPPH free radicals, hydroxyl free radicals, and ABTS free radicals was weakened. However, the T-AOC increased from 4.15 ± 0.81 to 8.43 ± 0.27 U/mL. Fermented beverage shows antibacterial activity against four pathogens. The minimum inhibitory concentration (MIC) values of Escherichia coli ATCC 25922 and Staphylococcus aureus ATCC 6538 were 0.05 mL/mL and 0.025 mL/mL, respectively, and the minimum bactericidal concentration (MBC) were both 0.2 mL/mL. It was observed by fluorescence microscope that the green fluorescence area of the two biofilms is greatly reduced after being treated with fermented beverage. Sensory analysis results show that the average scores of fermented beverage in color, appearance and taste were increased. The overall impression and flavor were decreased. CONCLUSION: These results demonstrated that strawberry fermented beverage has potential benefits such as an antioxidant, antibacterial, and anti-biofilm formation, providing the potential for the fermented beverage to become promising candidates for natural antioxidants, antibacterial agents and anti-biofilm agents.

11.
PeerJ ; 9: e11223, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33889449

RESUMO

BACKGROUND: Flavonoids are widely used in the market because of their antibacterial, antiviral, and antioxidant activities. But the production speed of flavonoids is limited by the growth of plants. CBL9 (Chaetomium cruentum) is a flavonoid-producing endophytic fungi from Conyza blinii H. Lév, which has potential to produce flavonoids. METHODS: In this study, we isolated total flavonoids from endophytic fungus CBL9 of Conyza blinii H. Lév using macroporous resin D101. The process was optimized by response surface and the best extraction process was obtained. The antioxidant activities of total flavonoids were analyzed in vitro. RESULTS: It was found that the best parameters were 25 °C pH 2.80, 1.85 h, and the adsorption ratio reached (64.14 ± 0.04)%. A total of 60% ethanol was the best elution solvent. The elution ratio of total flavonoid reached to (81.54 ± 0.03)%, and the purity was 7.13%, which was increased by 14.55 times compared with the original fermentation broth. Moreover its purity could rise to 13.69% after precipitated by ethanol, which is very close to 14.10% prepared by ethyl acetate extraction. In the antioxidant research, the clearance ratio of L9F-M on DPPH, ABTS, •OH, •O2-, (96.44 ± 0.04)% and (75.33 ± 0.03)%, (73.79 ± 0.02)%, (31.14 ± 0.01)% at maximum mass concentration, was higher than L9F. CONCLUSION: The result indicated using macroporous resin in the extraction of total flavonoid from endophytic fungus is better than organic solvents with higher extraction ratio, safety and lower cost. In vitro testing indicated that the flavonoid extracted by macroporous resin have good antioxidant activity, providing more evidence for the production of flavonoid by biological fermentation method.

12.
PeerJ ; 8: e9077, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32391207

RESUMO

BACKGROUND: Amaranthus hybridus L. is an annual, erect or less commonly ascending herb that is a member of the Amaranthaceae family. Polysaccharides extracted from traditional Chinese medicines may be effective substances with antioxidant activity. METHODS: In this study, we isolated crude polysaccharides from A. hybridus (AHP-M) using microwave-assisted extraction. Then, the AHP-M was purified by chromatography with DEAE-32 cellulose, and two fractions, AHP-M-1 and AHP-M-2, were obtained. The structural characteristics of AHP-M-1 and AHP-M-2 were investigated, and their antioxidant activities were analyzed in vitro. RESULTS: We found that the monosaccharide composition of AHP-M-1 was different from that of AHP-M-2. The molecular weights of AHP-M-1 and AHP-M-2 were 77.625 kDa and 93.325 kDa, respectively. The results showed that the antioxidant activity of AHP-M-2 was better than that of AHP-M-1. For AHP-M-2, the DPPH radical scavenging rate at a concentration of 2 mg/mL was 78.87%, the hydroxyl radical scavenging rate was 39.34%, the superoxide anion radical scavenging rate was 80.2%, and the reduction ability of Fe3+ was approximately 0.90. The total antioxidant capacity per milligram of AHP-M-2 was 6.42, which was higher than that of Vitamin C (Vc). CONCLUSION: The in vitro test indicated that AHP-M-1 and AHP-M-2 have good antioxidant activity, demonstrating that A. hybridus L. polysaccharide has immense potential as a natural antioxidants.

13.
PeerJ ; 8: e8978, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32328352

RESUMO

BACKGROUND: Conyza blinii H. Lév is a medicinal plant that has a variety of pharmacological activities, but its study is at a standstill due to the shortage of resources. METHOD: This study utilized the surface sterilization method to isolate endophytic fungi, and they were preliminarily identified by morphology. Flavonoid-producing strains were screened by NaNO2-Al(NO)3 colorimetry and further identified by the ITS sequence. Additionally, we used five antioxidant assays (DPPH, Hydroxyl radical, ABTS, FRAP and T-AOC assays) to systematically evaluate the antioxidant capacity of total flavonoids , and we also determined their antibacterial activity. RESULTS: In this study, 21 endophytic fungi were isolated from wild Conyza blinii H. Lév for the first time. There were six flavonoid-producing strains, especially CBL11, whose total flavonoid content reached 50.78 ± 2.4 mg/L. CBL12, CBL12-2 and CBL1-1 all exhibited excellent antioxidant activity. The effect of CBL12 was similar to that of ascorbic acid at low concentrations, and its radical scavenging rates for DPPH and ABTS were 94.56 ± 0.29 % and 99.88 ± 0.27%, respectively, while its IC50 values were only 0.11 ± 0.01 mg/mL and 0.2 ± 0.01 mg/mL. Through LC-MS, we found that CBL12 could produce many high-value flavonoids, such as 3-methoxyflavone, nobiletin, formononetin, scopoletin, and daidzein. Additionally, CBL9 had good antibacterial activity against both gram-positive and gram-negative bacteria. Notably, we obtained the high-yield strains CBL12 and CBL9, which not only had high yields (10.64 ± 1.01 mg/L and 10.17 ± 0.11 mg/L, respectively) but also had excellent biological activity. Hence, the results of this study provide new ideas for endophytic fungi that can be exploited as a source of flavonoids and other medicinal components from Conyza blinii H. Lév. Moreover, this study can serve as a reference for the development of rare medicinal materials.

14.
J Colloid Interface Sci ; 572: 114-121, 2020 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-32234587

RESUMO

A major issue hindering development of thin film nanocomposite (TFN) nanofiltration (NF) membrane is the interfacial defects induced by nanomaterial aggregation in top layer. Although various nanomaterials surface modification strategies have been developed to eliminate the interfacial defects, they usually involve extra modification steps and complex post-treatments. Inspired by the substrate-independent coating ability of tannic acid (TA) and the fact that the phenolic hydroxyl groups in TA can react with acyl chloride group in trimesoyl chloride, a TA coating solution containing TiO2 nanoparticles was used as an aqueous phase of interfacial polymerization to prepare interfacial modified TFN NF membranes in this study. Surface modification of TiO2 nanoparticles and interfacial polymerization can be carried out in a single step without any extra pre-modification step. It was found that the TA coating on TiO2 nanoparticles surface could decrease TiO2 aggregations and enhance interfacial compatibility between TiO2 and polyester matrix. The TFN NF membrane prepared at a TiO2 loading of 0.020 wt% exhibited a pure water flux of 28.8 L m-2 h-1 (284% higher than that of the controlled TFC membrane), and possessed enhanced NaCl and Na2SO4 rejections of 57.9% and 94.6%, respectively, breaking through the trade-off between permeability and selectivity.


Assuntos
Antibacterianos/farmacologia , Escherichia coli/efeitos dos fármacos , Nanocompostos/química , Taninos/farmacologia , Titânio/farmacologia , Antibacterianos/química , Antibacterianos/isolamento & purificação , Testes de Sensibilidade Microbiana , Tamanho da Partícula , Propriedades de Superfície , Taninos/química , Taninos/isolamento & purificação , Titânio/química , Titânio/isolamento & purificação
15.
J Colloid Interface Sci ; 565: 23-34, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-31931296

RESUMO

Nanofiltration (NF) membranes with tannic acid (TA) based selective layers have been intensively studied in recent years, but they still suffer from poor inorganic salt rejection. This study provided a first report on mussel-inspired co-deposition of TA and amine to obtain high-performance NF membranes. The inorganic salt separation performance of the as-prepared NF membrane was significantly improved by optimising the amine molecular weight. The membranes prepared by TA and various amines were characterised by X-ray photoelectron spectroscopy (XPS), attenuated total reflectance Fourier transform infrared (ATR-FTIR), scanning electron microscopy (SEM), zeta potential, and water contact angle measurement. It was found that amines with low molecular weight, such as ethylenediamine (EDA) and diethylenetriamine (DETA) facilitated the co-deposition onto the membrane surface, while polyethylene polyamine (PEPA) and branched polyethylenimine 600 (PEI600) enhanced the precipitation in solution. The TA/DETA co-deposited membrane showed an MgCl2 rejection of 83.5% and a pure water permeance of 4.5 L m-2 h-1 bar-1. The rejection was higher than the reported TA based NF membranes in the literature. In addition to demonstrating a TA based NF membrane with the improved inorganic salt rejection, this study provided new insights into the mussel-inspired co-deposition for material surface engineering towards various applications.

16.
J Colloid Interface Sci ; 560: 273-283, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31670100

RESUMO

Inspired by the mussel adhesion mechanism, plant polyphenol tannic acid (TA) with abundant catechol groups and hydrophilic Jeffamine (JA) containing amino groups were used in a layer-by-layer (LBL) process to fabricate composite nanofiltration (NF) membranes in this study. Alternately immersing a polyacrylonitrile substrate into individual TA and JA buffer solutions could readily construct a NF membrane selective layer without any pre-treatment to the substrate. The optimised membrane showed a high pure water permeance of 37 L m-2 h-1 bar-1 whilst maintaining rejections higher than 90% towards various dyes with molecular weights ranging from 269 to 1017 g mol-1. Particularly, the obtained membrane exhibited excellent anti-fouling and long-term performance attributed to the hydrophilic membrane surface and covalent bonds in the selective layer. The novel strategy inherited the advantages of a mussel-inspired dopamine material but overcame its disadvantages. The results disclosed in this study not only provide a novel strategy to prepare composite NF membranes, but also facilitate the mussel-inspired LBL design of advanced materials for environmental applications.

17.
PeerJ ; 7: e7149, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31223543

RESUMO

BACKGROUND: Amaranthus hybridus L. is an annual herb that belongs to the Amaranthceae family, a type of multi-purpose grain, vegetable and feed crop that has received considerable attention due to its great economic value. However, the composition of polysaccharides from A. hybridus has rarely been previously reported. METHODS: In this study, the aboveground part of A. hybridus was used as material and polysaccharides were isolated by the hot water extraction method. Two acidic polysaccharides were isolated and purified by the Sevage method and diethylaminoethyl cellulose-32 column chromatography. RESULTS: Two acidic polysaccharides were obtained from A. hybridus: AHP-H-1 and AHP-H-2. There were significant differences between the monosaccharide content from each sample according to gas chromatography-mass spectrometer. AHP-H-2 had higher antioxidant activity in vitro than AHP-H-1. The 2,2-diphenyl-1-picrylhydrazyl radical scavenging rate of two mg/mL AHP-H-2 was 80%, its hydroxyl radical scavenging rate was approximately 48.5%, its superoxide anion radical scavenging rate was 85.3% and its reduction ability of Fe3+ was approximately 0.92. The total antioxidant capacity of each milligram of AHP-H-2 was 6.5, which was higher than ascorbic acid. CONCLUSION: The results of the study promote the effective use of A. hybridus and provide a theoretical basis for its development.

18.
Gene ; 669: 63-68, 2018 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-29800734

RESUMO

To explore the role of genetic factors in the pathogenesis of hypertension, our study investigated the gender-specific association between four polymorphisms in the Apelin/APJ gene and hypertension risk in southeastern Chinese population. All participants including 645 hypertensive patients and 362 normotensive controls were genotyped for 4 gene polymorphisms associated with hypertension susceptibility including Apelin (rs909656, rs5975126) and APJ (rs10501367, rs11544374). According to genotype analysis, for male subjects, the frequencies of genotypes (P = 0.046 and 0.046, respectively) of rs10501367 and rs11544374 revealed significant differences between the hypertension and control groups. Moreover, for female subjects, there was significant difference on the genotype distribution of rs11544374 between two groups (P = 0.046). The association of rs10501367 with hypertension was significant for males under additive models and recessive models, even after adjusting for age, BMI, fasting glucose and waistline. Besides, significant association was observed for rs11544374 in females under additive models. As for haplotype analysis, haplotype T-A (in order of rs10501367 and rs11544374) in APJ gene was marginally overrepresented in controls (17.9%) compared to patients with hypertension (11.6%) in males (P = 0.003). The mutation of polymorphism rs10501367 in APJ gene decreased risk of hypertension in Chinese males.


Assuntos
Receptores de Apelina/genética , Apelina/genética , Hipertensão/genética , Adulto , Idoso , Pressão Sanguínea/genética , Estudos de Casos e Controles , China , Feminino , Haplótipos , Humanos , Hipertensão/diagnóstico , Masculino , Pessoa de Meia-Idade , Polimorfismo Genético , Fatores de Risco , Fatores Sexuais
19.
Int J Surg ; 54(Pt A): 201-205, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29678619

RESUMO

PURPOSE: To explore effect of goal-directed fluid therapy (GDFT) on early cognitive function in elderly patients with spinal stenosis. METHODS: 83 elderly patients with spinal stenosis were randomly classified into two groups: control group (n = 40) and GDFT group (n = 43). The Montreal Cognitive Assessment (MoCA) score, IL-6 and S100ß levels, hemodynamic parameters, cerebral oxygen saturation (rSO2), arterial lactic acid values, output of surgery, operation time and cases of hypotension, intraoperative complications within 7 days were recorded for all patients. RESULTS: The incidence of postoperative cognitive dysfunction (POCD) was about 21.67% in this study. The MoCA scores, inflammatory mediators, perfusion indexes (rSO2 and lactic acid)and intraoperative hemodynamics(HR, MAP, and CI)were not all the same at different time points (P < 0.05). The levels of inflammatory mediators (IL-6 and S100ß) in GDFT group were lower than those in the control group (P < 0.05). Total intake, amount of lactated Ringer's solution and cases of hypotension in GDFT group were significantly lower than control group (P < 0.05), but amount of voluven was higher than control group(P < 0.05). Compared with control group, the incidence of postoperative delirium, nausea and vomiting, and hypotension in GDFT group was lower (P < 0.05). CONCLUSIONS: GDFT can maintain the stability of perioperative hemodynamics in the prone position of elderly patients with spinal stenosis, improve the balance between perfusion of tissue and organ and supply and demand of oxygen, reduce the inflammatory response, and reduce the incidence of early POCD in this type of surgery.


Assuntos
Disfunção Cognitiva/terapia , Terapia Precoce Guiada por Metas/métodos , Hidratação/métodos , Complicações Pós-Operatórias/terapia , Estenose Espinal/psicologia , Idoso , Estudos de Casos e Controles , Cognição/efeitos dos fármacos , Disfunção Cognitiva/etiologia , Feminino , Hemodinâmica , Humanos , Derivados de Hidroxietil Amido/uso terapêutico , Soluções Isotônicas/uso terapêutico , Masculino , Complicações Pós-Operatórias/etiologia , Lactato de Ringer , Estenose Espinal/cirurgia , Resultado do Tratamento
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