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1.
J Clin Lab Anal ; : e23280, 2020 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-32167624

RESUMO

BACKGROUND: The Daan HCV RNA quantitative assay was a recently developed kit with high sensitivity for the detection of HCV RNA. We aimed to evaluate the analytical performance of the Daan HCV RNA quantitative assay and compare it with the COBAS AmpliPrep/COBAS TaqMan HCV Quantitative Test, v2.0. METHOD: WHO HCV RNA standard, NIBSC 06/102 standard, and CLSI EP documents were used to evaluate the precision, accuracy, linearity, anti-interference ability, and cross-reactivity of the Daan HCV RNA quantitative assay. Overall 198 clinical serum specimens were used to make comparison between the Daan HCV RNA quantitative assay and the Roche Cobas test. RESULTS: The within-run precision (Swithin ), and total precision (Stotal ) for 6.11 log IU/mL, 4.22 log IU/mL, and 2.32 log IU/mL HCV RNA were 0.13 and 0.15, 0.07 and 0.09, and 0.11 and 0.10, respectively. The linear range was 20-108  IU/mL, and the limit of detection was 15 IU/mL. It did not display any interference with commonly encountered conditions and cross-reactivity with some common virus. A good agreement was observed between the Daan HCV RNA quantitative assay and the Roche Cobas test. CONCLUSION: The Daan HCV RNA quantitative assay has shown satisfactory performances and excellent agreement with COBAS HCV Quantitative Test on clinical specimens with lower cost, which provides an alternative choice for the diagnosis and monitoring of HCV infection in developing countries.

2.
Appl Biochem Biotechnol ; 190(2): 423-436, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31376051

RESUMO

Lignocellulosic hydrolysate contains complex nonsugar compounds and undegraded sugars in the process of preparing platform compound levulinic acid (LA) and furfural by one-step dilute-acid hydrolysis. For efficiently and comprehensively utilizing the hydrolysate, a series of polar modified resins were synthesized for adsorption and separation of the sugarcane bagasse hydrolysate to obtain platform compounds and fermentable hydrolysate simultaneously. The adsorption capacities of LA and furfural were optimized to 85.32 mg/g and 33.55 mg/g on polar modified resin prepared with 80 wt% glycidyl methacrylate (GMA -80), which was much higher than nonpolar resin (4.16 mg/g and 16.14 mg/g). GMA-80 obtained the best comprehensive adsorption property, whose desorption rates were 99.90% and 89.86% for LA and furfural, respectively, and its regeneration performance was also excellent, indicating that the resin is a potential adsorbent and expected to be used in the separation and purification of the lignocellulosic hydrolysate.

3.
Bioresour Technol ; 299: 122625, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31881437

RESUMO

The production of high-purity xylobiose from lignocellulose is an expensive and tedious process. In this work, the production of xylobiose from enzymatic hydrolysis of alkaline oxidation pretreated sugarcane bagasse was investigated. Furthermore, a simple process for the separation of xylobiose from enzymatic hydrolysate by activated carbon absorption, water washing, and ethanol-water desorption was developed. Under the optimized separation conditions, 96.77% xylobiose was adsorbed at 16% activated carbon loadings. Moreover, xylose and acetate could not be detected after washing by 3-fold volume of water. Xylobiose with 80.16% yield was eluted by 5-fold volume of 5% (v/v) ethanol-water. The reusability of activated carbon was evaluated by 5 cycles of adsorption-desorption process, suggesting that the activated carbon exhibited good reusability. The separated xylobiose sample with high-purity (97.29%) was confirmed by HPLC, ESI-MS, and NMR. Overall, this study provided a low-cost and robust technology for the production and separation of high-purity xylobiose from lignocellulose.


Assuntos
Saccharum , Celulose , Dissacarídeos , Hidrólise
4.
Int J Mol Med ; 44(1): 79-88, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31115490

RESUMO

In hepatolithiasis, chronic proliferative cholangitis (CPC), an active and longstanding inflammation of stone­containing bile ducts with enhanced mucin­producing activity, not only affects the progression of the disease, it can also induce biliary carcinogenesis. The present study aimed to examine the effect of the epidermal growth factor receptor (EGFR) monoclonal antibody panitumumab (Pani) on CPC. Following the establishment of CPC rat models, periodic acid Schiff staining was used to observe the positive rate of EGFR expression. The expression levels of EGFR, mucin 5AC (MUC5AC), Ki­67, type I collagen and mammalian target of rapamycin (mTOR), and the activity of ß­glucuronidase (ß­G), were measured. The rats treated with Pani demonstrated a significantly lower degree of hyperproliferation of the epithelium and submucosal glands of the bile duct and collagen fibers of the bile duct wall, a significantly decreased positive rate of EGFR, reduced phosphorylation of mTOR, decreased expression of EGFR, MUC5AC, Ki­67 and type I collagen, and reduced ß­G activity. The therapeutic effects in rats treated with 4 and 6 mg/kg of Pani were more marked than those in rats treated with 2 mg/kg of Pani. Collectively, the data obtained in the present study suggest that the EGFR monoclonal antibody Pani can effectively inhibit the excessive proliferation and stone­forming potential of bile duct mucosa in CPC with a receptor saturation effect. Therefore, Pani offers promise as a treatment for the prevention and control of intrahepatic choledocholithiasis caused by CPC.


Assuntos
Ductos Biliares/metabolismo , Proliferação de Células/efeitos dos fármacos , Colangite/tratamento farmacológico , Regulação para Baixo/efeitos dos fármacos , Receptores ErbB/biossíntese , Panitumumabe/farmacologia , Animais , Ductos Biliares/patologia , Colangite/metabolismo , Colangite/patologia , Doença Crônica , Masculino , Ratos , Ratos Sprague-Dawley
5.
Prep Biochem Biotechnol ; 49(6): 597-605, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30929602

RESUMO

A simple and accurate Nile Red fluorescent method was built to evaluate the lipid content of three different oleaginous yeasts by one standard curve. The staining of cells can be observed clearly by laser scanning confocal microscope, showing that Nile Red can enter into the cells of oleaginous yeasts easily. A series of conditions such as pretreating temperature, cell suspension concentration (OD600), staining time, Nile Red concentration and the type of suspension solvent were learnt systematically to obtain the optimal process parameters for Nile Red staining. After optimization, the fitting curve of Nile Red fluorescent method was established under suitable conditions (pretreating temperature: 50 °C, OD600: 1.0; staining time: 5 mins; Nile Red concentration: 1.0 µg/mL; suspension solvent: PBS) and it had a suitable correlation coefficient (R2 = 0.95) for lipid content measurement of different oleaginous yeasts. By this study, the possibility of lipid content determination of different oleaginous yeasts by one fitting curve can be proven and this will improve the efficiency of researches related to microbial lipid production.


Assuntos
Corantes Fluorescentes/química , Lipídeos/análise , Microscopia Confocal/métodos , Oxazinas/química , Leveduras/química , Cryptococcus/química , Lipomyces/química , Coloração e Rotulagem/métodos , Temperatura Ambiente , Trichosporon/química
6.
Bioresour Technol ; 283: 191-197, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30908983

RESUMO

Elephant grass (Pennisetum purpureum) acid hydrolysate was used as substrate for anaerobic digestion for the first time. Within short period (ten days), the organic materials (sugars and organic acids) in the elephant grass hydrolysate could be utilized efficiently for stable biogas production that the COD removal, biogas yield, and CH4 content were 91.3 ±â€¯2.0%, 0.561 ±â€¯0.014 m3/kg COD consumption, and 68.1 ±â€¯4.6%, respectively throughout this bioprocess. During anaerobic digestion, almost no volatile fatty acids (VFAs) was accumulated (merely <0.1 g/L acetic acid was found) and the outlet pH was very stable (7.3 ±â€¯0.1). Meanwhile, the furans including furfural and 5-hydroxymethylfurfural (HMF) existing in the inlet substrate could be degraded. After anaerobic digestion, the outlet effluent was treated by combination of Fe-C micro-electrolysis and Fenton reaction to remove 93.1% of residual COD and 98.6% of color. Considering the performance, cost, operation, and environmental influence, this technology is suitable for industrial treatment of waste elephant grass.


Assuntos
Biocombustíveis , Pennisetum/metabolismo , Anaerobiose , Reatores Biológicos , Ácidos Graxos Voláteis/metabolismo , Metano/metabolismo
7.
Sci Total Environ ; 663: 447-452, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-30716636

RESUMO

Wastewater treatment is one important issue for turpentine plant and more wastewater generated by greater turpentine processing will prevent its further development. To solve this issue without extra place and new equipment, one industrial system for reuse and treatment of turpentine processing wastewater was introduced for the first time. For wastewater reuse, the technology was simple and easy to control that after neutralization by lime and absorption with activated carbon (optional, mostly not necessary), the wastewater could be reused for turpentine processing. After reuse, the wastewater was further treated by a biological system. During long-term application of wastewater reuse in this plant, it showed little influence on the products performance (mainly acid value) and final wastewater COD. Base on above advantages, the plant could decide when for wastewater drainage, and thus the amount of wastewater was reduced greatly. For the biological treatment, the COD of wastewater could be degraded to suitable level stably and the wastewater after treatment could be applied for daily life in the plant. Overall, considering the cost, operation, and performance, the whole system shows great potential and possibility of industrial application and therefore can be applied widely in the turpentine processing industry.

8.
Carbohydr Polym ; 208: 421-430, 2019 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-30658820

RESUMO

Superabsorbent was synthesized from bacterial cellulose (BC) generated by in situ fermentation on bentonite inorganic gel (BIG). For BIG preparation, the effect of sodium agent's type and content, temperature and time of sodium-modification, and gelling agent's type and content on the viscosity of BIG were learned to optimize the synthesis process. For polymerization, the effect of different factors including ratio of monomer to substrate (modified BC from in situ fermentation), content of initiator and crosslinker, monomer neutralization degree, reaction temperature and time on the performance of composite (superabsorbent) synthesized were analyzed. Under optimal condition, the composite showed good water absorption, salts absorption, and water retention capacity. The original bentonite, sodium-based bentonite, BIG and composite structure was characterized by X-ray fluorescence (XRF), nuclear magnetic resonance (NMR), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscope (SEM) and thermogravimetric analysis (TGA), and the characterization partly explained the performance of water absorption and thermal stability of the composite. Overall, this study provides one method for superabsorbent synthesis from low-cost and natural resources.


Assuntos
Bactérias/classificação , Celulose/metabolismo , Argila/química , Bentonita/química , Celulose/química , Fermentação , Água/química
9.
Bioresour Technol ; 275: 345-351, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30597396

RESUMO

High chemical input is required for enzymatic production of xylo-oligosaccharides (XOS) using xylan extracted from lignocellulosic biomass. In this study, enzymatic hydrolysis of alkaline oxidation (AO) treated sugarcane bagasse (SCB) directly for the production of XOS was conducted. The effect of AO pretreatment on the chemical compositions and hydrolytic properties of SCB was investigated. The AO pretreatment conditions with low chemical input for the production of XOS were optimized by orthogonal design. Stepwise enzymatic hydrolysis of AO pretreated SCB with xylanase and cellulase produced XOS (1.78 g/L), meanwhile, the cellulose conversion increased from 84.97% to 91.51% compared with directly enzymatic hydrolysis using cellulase. HPLC-UV and MALDI-TOF-MS analysis indicated that the obtained XOS products were mainly composed of xylobiose and xylose with a small amount of arabinose/4-O-methylglucuronic acid substituted xylotriose and xylotetraose. The proposed strategy for the co-production of functional XOS and fermentable sugars from SCB showed potential of industrial application.


Assuntos
Celulose/metabolismo , Oligossacarídeos/biossíntese , Saccharum/metabolismo , Açúcares/metabolismo , Álcalis , Biomassa , Fermentação , Hidrólise , Oxirredução
10.
Appl Biochem Biotechnol ; 188(3): 585-601, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30552624

RESUMO

An adsorption resin CX-6 was synthesized and used for acid soluble lignin (ASL) removal from sugarcane bagasse hydrolysate (SCBH). The adsorption conditions of pH value, amount of adsorbent, initial ASL concentration, and temperature on ASL adsorption were discussed. The results showed the adsorption capacity of ASL was negatively affected by increasing temperature, solution pH, and adsorbent dose, and was positively affected by increasing initial concentration. The maximum adsorption capacity of ASL was 135.3 mg/g at initial ASL concentration 6.46 g/L, adsorption temperature 298 K, and pH 1. Thermodynamic study demonstrated that the adsorption process was spontaneous and exothermic. Equilibrium and kinetics experiments were proved to fit the Freundlich isotherm model and pseudo-second-order model well, respectively. Fermentation experiment showed that the SCBH after combined overliming with resin adsorption as fermentation substrate for microbial lipid production by Trichosporon cutaneum and Trichosporon coremiiforme was as better as that of SCBH by combined overliming with active charcoal adsorption, and more efficient than that of SCBH only by overliming. Moreover, the regeneration experiment indicated that the CX-6 resin is easy to regenerate and its recirculated performance is stable. In conclusion, our results provide a promising adsorbent to detoxify lignocellulose hydrolysate for further fermentation.


Assuntos
Ácidos/química , Lignina/isolamento & purificação , Lipídeos/biossíntese , Saccharum/química , Adsorção , Fermentação , Concentração de Íons de Hidrogênio , Hidrólise , Lignina/química , Microscopia Eletrônica de Varredura , Solubilidade , Temperatura Ambiente , Termodinâmica , Trichosporon/metabolismo
11.
Materials (Basel) ; 11(10)2018 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-30250001

RESUMO

Gel polymer electrolyte (GPE) is widely considered as a promising safe lithium-ion battery material compared to conventional organic liquid electrolyte, which is linked to a greater risk of corrosive liquid leakage, spontaneous combustion, and explosion. GPE contains polymers, lithium salts, and liquid electrolyte, and inorganic nanoparticles are often used as fillers to improve electrochemical performance. However, such composite polymer electrolytes are usually prepared by means of blending, which can impact on the compatibility between the polymer and filler. In this study, the hybrid copolymer poly (organic palygorskite-co-methyl methacrylate) (poly(OPal-MMA)) is synthesized using organic palygorskite (OPal) and MMA as raw materials. The poly(OPal-MMA) gel electrolyte exhibits an ionic conductivity of 2.94 × 10-3 S/cm at 30 °C. The Li/poly(OPal-MMA) electrolyte/LiFePO4 cell shows a wide electrochemical window (approximately 4.7 V), high discharge capacity (146.36 mAh/g), and a low capacity-decay rate (0.02%/cycle).

12.
Psychiatry Res ; 267: 187-194, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29913377

RESUMO

Self-disturbances are increasingly recognized as important, possibly even central, features of schizophrenia. However, little is known about the associations among different manifestations of self-disturbances. The aims of the current study were threefold. We aimed to (1) replicate previous findings of increased self-disturbances in schizophrenia, (2) correlate manifestations of self-disturbances in schizophrenia across three domains, and (3) correlate self-disturbances with five symptoms domains of schizophrenia, including positive, negative, disorganized symptoms, excitement, and emotional distress. We examined three domains of self-experience, including somatosensation, anomalous self-experiences, and self-concept clarity. Participants included 48 individuals with schizophrenia and 36 non-psychiatric controls. The results of this study replicate previous findings of significantly higher levels of self-disturbances in people with schizophrenia. The results also indicate positive correlations between the domains of anomalous self-experiences and self-concept clarity, but not somatosensation, in individuals with schizophrenia. As well, anomalous self-experiences were positively correlated with positive symptoms, disorganized symptoms, and emotional distress and self-concept clarity was negatively correlated with disorganized symptoms and emotional distress.


Assuntos
Esquizofrenia/diagnóstico , Psicologia do Esquizofrênico , Autoimagem , Adulto , Antipsicóticos/uso terapêutico , Emoções , Feminino , Humanos , Masculino , Esquizofrenia/tratamento farmacológico , Esquizofrenia/epidemiologia , Distúrbios Somatossensoriais/diagnóstico , Distúrbios Somatossensoriais/tratamento farmacológico , Distúrbios Somatossensoriais/epidemiologia
13.
J Colloid Interface Sci ; 513: 788-796, 2018 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-29222978

RESUMO

A novel type of cobalt nanofibers coated with layered nickel silicate (Co nanofibers @ voids @ Ni3Si2O5(OH)4) coaxial core-shell composites were successfully prepared via a well-known Stöber process and two hydrothermal methods. In the composites, the international nanosheet structure of the nickel silicate provided interlayer spaces for lithium ions in the process of insertion and extraction. The cobalt nanofibers served as a mechanical support for the nickel silicate nanosheets, which increased the electrical conductivity of the whole electrode. In addition, one-dimensional coaxial structure was stable to buffer the volume change and avoid the destruction of the structure. Moreover, the voids provided effective channels for the transportation of lithium ions. The Co nanofibers @ voids @ Ni3Si2O5(OH)4) coaxial core-shell composites presented superior electrochemical properties compared with the published Ni3Si2O5(OH)4-related materials. With the advantages of exceptional performances and facile preparation, the composites show prospective application potential as advanced anode materials in lithium ion batteries.

14.
J Colloid Interface Sci ; 509: 1-9, 2018 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-28881199

RESUMO

The preparation of highly efficient and cheap electrocatalysts toward oxygen reduction reaction is significant for many electrochemical cells. Here we facilely synthesized nitrogen doped carbon nanotube by pyrolyzing melamine formaldehyde resin and Fe loading on MgO. There were mainly three morphologies observed, slender bamboo-like CNT, thick bamboo-like CNT, surface smooth, hollow CNT. The content of Fe loading on MgO had little influence on morphologies of CNT, however, when no MgO as support, only carbon ribbon obtained. The MgO as support was also significant for the formation of CNT. The samples with CNT formed represented better catalytic activity than control samples with no-CNT obtained, the morphology of CNT was beneficial for catalytic process. The sample C1-CNT with lowest content of Fe on support represented best catalytic activity which was competitive with 20% Pt/C in half-wave potential. The C1-CNT also showed outstanding stability and improved selectivity towards ORR, making it a promising alternative to Pt in application of fuel cells and metal-air batteries.

15.
Polymers (Basel) ; 10(7)2018 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-30960627

RESUMO

Cellulose-based superabsorbent was synthesized by bacterial cellulose (BC) grafting acrylic acid (AA) in the presence of N,N'-methylenebisacrylamide (NMBA) as a crosslinker and ammonium persulfate (APS) as an initiator. The influence of different factors on composite synthesis, including the weight ratio of the monomer to BC, initiator content, crosslinker content, AA neutralization degree, reaction temperature, and reaction time on the water absorbency of the composite, were systematically learned. Under the optimized conditions, the maximum water absorbency of the composite was 322 ± 23 g/g distilled water. However, the water absorbency was much less for the different salt solutions and the absorption capacity of the composite decreased as the concentration of the salt solutions increased. The pH value had a significant influence on water absorption performance, and with the increase of temperature, the water retention rate of the composite decreased. Additionally, the structure of this composite was characterized with nuclear magnetic resonance (NMR), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), and thermogravimetric analysis (TGA). The results of NMR and FT-IR provided evidence that the composite was synthesized by BC and AA, and the microstructure showed that it had good performance for water absorption. In addition, the composite possessed suitable thermal stability, and that it could be used in a few high-temperature environments. Overall, this composite is promising for application in water absorption.

16.
J Agric Food Chem ; 65(51): 11237-11242, 2017 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-29200277

RESUMO

In this study, a fast startup of semi-pilot-scale anaerobic digestion of food waste acid hydrolysate for biogas production was carried out for the first time. During the period of fast startup, more than 85% of chemical oxygen demand (COD) can be degraded, and even more than 90% of COD can be degraded during the later stage of anaerobic digestion. During this anaerobic digestion process, the biogas yield, the methane yield, and the CH4 content in biogas were 0.542 ± 0.056 m3/kgCOD consumption, 0.442 ± 0.053 m3/kgCOD consumption, and 81.52 ± 3.05%, respectively, and these values were high and stable. Besides, the fermentation pH was very stable, in which no acidification was observed during the anaerobic digestion process (outlet pH was 7.26 ± 0.05 for the whole anaerobic digestion). Overall, the startup of this anaerobic digestion can be completed in a short period (the system can be stable 2 days after the substrate was pumped into the bioreactor), and anaerobic digestion of food waste acid hydrolysate is feasible and attractive for industrial treatment of food waste and biogas production.


Assuntos
Biocombustíveis/análise , Metano/análise , Resíduos/análise , Anaerobiose , Reatores Biológicos , Projetos Piloto , Esgotos/química
17.
Indian J Microbiol ; 57(4): 393-399, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29151639

RESUMO

Durian is one important tropical fruit with high nutritional value, but its shell is usually useless and considered as waste. To explore the efficient and high-value utilization of this agricultural and food waste, in this study, durian shell was simply hydrolyzed by dilute sulfuric acid, and the durian shell hydrolysate after detoxification was used for bacterial cellulose (BC) production by Gluconacetobacter xylinus for the first time. BC was synthesized in static culture for 10 days and the highest BC yield (2.67 g/L) was obtained at the 8th day. The typical carbon sources in the substrate including glucose, xylose, formic acid, acetic acid, etc. can be utilized by G. xylinus. The highest chemical oxygen demand (COD) removal (16.40%) was obtained at the 8th day. The highest BC yield on COD consumption and the highest BC yield on sugar consumption were 93.51% and 22.98% (w/w), respectively, suggesting this is one efficient bioconversion for BC production. Durian shell hydrolysate showed small influence on the BC structure by comparison with the structure of BC generated in traditional Hestrin-Schramm medium detected by FE-SEM, FTIR, and XRD. Overall, this technology can both solve the issue of waste durian shell and produce valuable bio-polymer (BC).

18.
Prep Biochem Biotechnol ; 47(10): 1025-1031, 2017 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-28857665

RESUMO

Biomass acid hydrolysate of oleaginous yeast Trichosporon cutaneum after microbial oil extraction was applied as substrate for bacterial cellulose (BC) production by Komagataeibacter xylinus (also named as Gluconacetobacter xylinus previously) for the first time. BC was synthesized in static culture for 10 days, and the maximum BC yield (2.9 g/L) was got at the 4th day of fermentation. Most carbon sources in the substrate (glucose, mannose, formic acid, acetic acid) can be utilized by K. xylinus. The highest chemical oxygen demand (COD) removal (40.7 ± 3.0%) was obtained at the 6th day of fermentation, and then the COD increased possibly due to the degradation of BC. The highest BC yield on COD consumption was 38.7 ± 4.0% (w/w), suggesting that this is one efficient bioconversion for BC production. The BC structure was affected little by the substrate by comparison with that generated in classical HS medium using field-emission scanning electron microscope (FE-SEM), Fourier transform infrared, and X-ray diffraction. Overall, this technology can both solve the issue of waste oleaginous yeast biomass and produce valuable biopolymer (BC).


Assuntos
Biomassa , Celulose/metabolismo , Gluconacetobacter xylinus/metabolismo , Microbiologia Industrial/métodos , Óleos/isolamento & purificação , Trichosporon/metabolismo , Ácidos/metabolismo , Análise da Demanda Biológica de Oxigênio , Fermentação , Hidrólise , Óleos/metabolismo , Resíduos Sólidos/análise , Trichosporon/química
19.
Carbohydr Polym ; 175: 199-206, 2017 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-28917857

RESUMO

Understanding the interaction mechanisms between xylan and xylan-degrading enzymes is beneficial to the efficient hydrolysis of xylan. Xylan from sugarcane bagasse (SB) was extracted and characterized. The effects of heat treatment and removal of side chains of SB xylan on the hydrolytic efficiency and synergistic action of endo-ß-1,4-xylanases (HoXyn11A and AnXyn10C), ß-xylosidases (AnXln3D), and α-l-arabinofuranosidases (AnAxh62A) were investigated. Results indicated that heat treatment of xylan can improve the hydrolytic efficiency of xylan-degrading enzymes, and it is essential for the efficient hydrolysis of xylan by HoXyn11A. The removal of arabinofuranosyl side chains of xylan by AnAxh62A before enzymatic hydrolysis reduced the hydrolytic efficiency of HoXyn11A and AnXyn10C on xylan. AnXyn10C was more efficient than HoXyn11A in hydrolysis of xylan, whereas HoXyn11A showed better synergistic action than AnXyn10C with AnAxh62A and AnXln3D in the hydrolysis of xylan. This study provides new insights on the enzymatic hydrolysis of SB into monosaccharides and xylo-oligosaccharides.


Assuntos
Celulose/química , Endo-1,4-beta-Xilanases/metabolismo , Saccharum/química , Xilanos/metabolismo , Hidrólise
20.
J Colloid Interface Sci ; 506: 291-299, 2017 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-28738280

RESUMO

Well-designed hierarchical nanostructured composites consisting of one dimensional cobalt fibers and thin tin disulfide nanosheets were successfully synthesized for the first time through a hydrothermal method. The SnS2 nanosheets were uniformly grown onto the Co fibers and were almost perpendicular to the Co fibers. The composites as one kind anode materials exhibited more remarkable lithium ion storage properties than SnS2 nanosheets. The composites exhibited a capacity of 500.5mAh/g after 100 cycles even at 1000mA/g. The improved electrochemical performance could be assigned to the Co fiber substrate support, which could provide short lithium ion and electron pathways, alleviate large volume expansion, contribute to the capacity, and offer mechanical stability for the anode electrode. This special designing perhaps could lay a foundation for the preparation of high performance lithium ion battery anode materials.

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