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Over the years, the concentration of cadmium in soil has increased due to industrialization. Cadmium in the soil enters the human body through plant accumulation, seriously endangering human health. In the current study, two types of hydrogels were successfully synthesized using a free radical polymerization method: an ion-type hydrogel referred to as DMAPAA (N-(3-(Dimethyl amino) propyl) acrylamide)/DMAPAAQ (N,N-Dimethyl amino propyl acrylamide, methyl chloride quaternary) and a non-ion-type hydrogel known as DMAA (N,N-Dimethylacrylamide). In the experiment carried out in this study, the ion-type hydrogel DMAPAA/DMAPAAQ was introduced to cadmium-contaminated soil for vegetable cultivation. The study found that at cadmium levels of 0 and 2 mg/kg in soil, when exposed to a pH 2 solution, cadmium wasn't detected in the filtrate using ICP. As the amount of cadmium increased to 500 mg/kg, hydrogel addition gradually reduced the filtrate cadmium concentration. Notably, the use of the 4% hydrogel resulted in 0 mg/L of cadmium. For the 0% hydrogel, vegetable cadmium absorption was determined to be 0.07 mg/g, contrasting with 0.03 mg/g for the 4% hydrogel. The DMAPAA/DMAPAAQ hydrogel significantly boosts vegetable growth by efficiently absorbing nitrate ions through ion exchange, releasing them for plant uptake. In contrast, the DMAA hydrogel, used as a control, does not enhance plant growth despite its water absorption properties. In summary, the composite hydrogel shows great potential for enhancing vegetable yield and immobilizing heavy metals in soil.
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Bisphenol A (BPA) degradation efficiency by bacteria or by metal-organic-frameworks (MOFs) catalyzed persulfate (PMS) oxidation have been studied intensively. However, their synergistic effect on BPA degradation was less reported. In this study, we combined previously synthesized CNT-hemin/Mn-MOF with an BPA degrading bacteria SQ-2 to form a composite (SQ-2@MOFs). CNT-hemin/Mn-MOF in the composite catalyzed little PMS to promote the degradation efficiency of SQ-2 on BPA. Results indicated SQ-2@MOFs significantly accelerated BPA degradation rate than SQ-2 alone. Furthermore, SQ-2@MOFs composite was successfully immobilized in hydrogel to achieve better degradation performance. Immobilized SQ-2@MOFs could almost completely degrade 1-20 mg/L BPA within 24 h and completely degrade 5 mg/L BPA at pH 4-8. Besides, degradation byproducts also reduced by immobilized SQ-2@MOFs, which promoted the cleaner biodegradation of BPA. Metabolomics and multiple chemical characterization results revealed the interconnection mechanism between CNT-hemin/Mn-MOFs, SQ-2 and hydrogel. CNT-hemin/Mn-MOF helped SQ-2 degrade BPA into more biodegradable products, promoted electron transfer, and augmented BPA degradation ability of SQ-2 itself. SQ-2 enabled the surface electronegativity of SQ-2@MOFs more suitable for BPA contact. Meanwhile, SQ-2 avoided the loss of Fe and Mn of CNT-hemin/Mn-MOF. Hydrogel augmented the above synergistic effect. This study provided new perspective for the development of biodegradation materials through interdisciplinary integration.
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Compostos Benzidrílicos , Biodegradação Ambiental , Hidrogéis , Estruturas Metalorgânicas , Fenóis , Compostos Benzidrílicos/química , Compostos Benzidrílicos/metabolismo , Fenóis/química , Fenóis/metabolismo , Hidrogéis/química , Estruturas Metalorgânicas/química , Poluentes Químicos da Água/química , Poluentes Químicos da Água/metabolismo , Bactérias/metabolismoRESUMO
This study aims to solve the problem of cadmium heavy metal ion pollution caused by the abuse of chemical fertilizers and activities such as mining, which pose a serious threat to the plant growth environment. We successfully synthesized DMAPAA (N-(3-(Dimethyl amino) propyl) acrylamide)/DMAPAAQ (N, N-Dimethyl amino propyl acrylamide, methyl chloride quaternary) hydrogels via free radical polymerization. Subsequently, we conducted experiments on this hydrogel for growing vegetables under cadmium stress conditions in aqueous solutions and soil. The cadmium capture capacity of DMAPAA/DMAPAAQ hydrogels under different cadmium ion concentrations and pH values was evaluated by using inductively coupled plasma optical emission spectrometry (ICP). The research results show that under the condition of pH = 7.3, the cadmium capture capacity of DMAPAA/DMAPAAQ hydrogels is the greatest. We used the Langmuir model to fit the adsorption data, and the correlation coefficient was as high as 0.96, indicating that the model fits well. The application of the hydrogels promoted the growth of vegetables in soil under cadmium stress conditions. The results showed that when the added amount of hydrogel was 4%, the dry weight of the vegetables was the largest. In addition, when the added amount of cadmium was 500 mg/kg and the added amount of hydrogel was 4%, the absorption of cadmium by the vegetables decreased to an undetectable level. In summary, the hydrogel successfully synthesized in this study can be effectively used to immobilize cadmium ions in soil while positively promoting the growth and yield of vegetables. This achievement has practical significance for solving the problem of heavy metal ion pollution.
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This study presents a comparative analysis of several commercial removable materials for radioactive decontamination of steel surfaces using 241Am as representative radionuclide. The selection criteria of removable coatings for this study included a history of application, commercial availability, easy handling conditions and different composition and formulation. Carbon steel and stainless steel coupons were utilized as common industrial materials, and the experimental series were expanded to include the rusting treatment of these surfaces as it is common for decommissioned nuclear facilities. Radionuclide 241Am was deposited on the coupon surfaces and used to evaluate decontamination efficiency of the removable coatings, which were pre-screened for the ease of application and removal from the surface. Selected coatings were characterized with Fourier-transform infrared spectroscopy and thermogravimetric analysis, decontamination efficiencies for different types of steel surfaces, and potential enhancement of the removal efficiencies of the select removable coatings via amendment with EDTA. Across all the coatings, decontamination efficiencies for stainless steel (both pristine and with oxidizing treatment) were higher than for pristine carbon steel, which in turn were higher than for rusted carbon steel. Amendment with EDTA improved removal efficiency of a removable coating. CC Strip coating exhibited easy handling and high decontamination efficiency, (up to 97% when EDTA-amended), but its drying time was the longest, and thermal analysis indicated higher release of energy during thermal decomposition compared to the other coatings. Hydrogel-based DeconGel coating, even though not the easiest in handling among the rest of materials, exhibited high decontamination efficiency, efficient drying at the ambient temperature leading to the loss of about 80 wt% due to solvent evaporation, and extremely low heat released during thermal decomposition; therefore, it is considered a preferable choice for the considered factors.
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Aço Inoxidável , Aço , Carbono , Descontaminação/métodos , Ácido Edético , Radioisótopos/químicaRESUMO
Enzyme reaction has been accepted widely in numerous applications owing to the high efficiency and stereo-selectivity, as well as simple preparation by gene engineering. However, the fragility and complex purification process of the enzyme are long-standing problems which limit the large-scale application. One possible solution may be the enzyme immobilization. As one type of porous material with high loading capacity and designable functionality, Metal-Organic Frameworks (MOFs) are ideal choices for the immobilization of enzyme with a considerable interest in recent years. In this study, d-amino acid transaminase (DAT), an important enzyme for industrial synthesis of d-Ala, was covalently immobilized on the surface of a star MOFs material, UiO-66-NH2. Interestingly, we found that the nanoscale hybrid enzyme UiO-66-NH2-Gd-DAT not only maintained the high catalytic efficiency but also got rid of the interference of polluting enzymes, which meant that we could obtain efficient and stereo-selective immobilized enzyme without complex purification process. In general, our findings demonstrated that using UiO-66-NH2 might be a promising strategy to immobilize enzyme and produce effective biocatalyst with high activity and stereo-selectivity.
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Alanina/biossíntese , Compostos Organometálicos/química , Ácidos Ftálicos/química , Transaminases/química , Adsorção , Aminoácidos , Catálise , Enzimas Imobilizadas/química , Estruturas Metalorgânicas/química , Porosidade , Transaminases/metabolismo , Água , Purificação da ÁguaRESUMO
Current worldwide challenges are to increase the food production and decrease the environmental contamination by industrial emissions. For this, bacteria can produce plant growth promoter phytohormones and mediate the bioremediation of sewage by heavy metals removal. We developed a Rational Design of Immobilized Derivatives (RDID) strategy, applicable for protein, spore and cell immobilization and implemented in the RDID1.0 software. In this work, we propose new algorithms to optimize the theoretical maximal quantity of cells to immobilize (tMQCell) on solid supports, implemented in the RDIDCell software. The main modifications to the preexisting algorithms are related to the sphere packing theory and exclusive immobilization on the support surface. We experimentally validated the new tMQCell parameter by electrostatic immobilization of ten microbial strains on AMBERJET® 4200 Cl- porous solid support. All predicted tMQCell match the practical maximal quantity of cells to immobilize with a 10% confidence. The values predicted by the RDIDCell software are more accurate than the values predicted by the RDID1.0 software. 3-indolacetic acid (IAA) production by one bacterial immobilized derivative was higher (~ 2.6 µg IAA-like indoles/108 cells) than that of the cell suspension (1.5 µg IAA-like indoles/108 cells), and higher than the tryptophan amount added as indole precursor. Another bacterial immobilized derivative was more active (22 µg Cr(III)/108 cells) than the resuspended cells (14.5 µg Cr(III)/108 cells) in bioconversion of Cr(VI) to Cr(III). Optimized RDID strategy can be used to synthesize bacterial immobilized derivatives with useful biotechnological applications.
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Biodegradação Ambiental , Células Imobilizadas/metabolismo , Biologia Computacional/métodos , Algoritmos , Bactérias/metabolismo , Biomassa , Poluentes Ambientais , Metais Pesados/metabolismo , Software , Eletricidade EstáticaRESUMO
OBJECTIVES: To elucidate whether a modified technique for anterior reconstruction could improve urinary continence after robot-assisted laparoscopic radical prostatectomy (RALP). METHODS: Among 325 consecutive patients who underwent RALP at our hospital, 297 patients were included in this retrospective study, who had complete records including the status of postoperative urinary continence. Among these 297 patients, 194 underwent anterior reconstruction by suturing the lateral bladder wall to the arcus tendineus of the pectineal fascia without fixation of the vesicourethral anastomosis site to the dorsal vein complex (DVC) (lateral-suture group). In the remaining 103 patients, simple suturing of the bladder neck muscle layer at the vesicourethral anastomosis site with DVC to immobilize the vesicourethral anastomosis site (immobilized group) was performed. Those who did not required a pad was defined as continent. RESULTS: Operative and console times were significantly shorter in the immobilized group (242 vs. 268 min; p = 0.03, and 174 vs. 203 min; p = 0.009, respectively). Although there was no significant difference between the groups regarding the recovery of urinary continence within 3 months after RALP (21 vs. 22% at 1 month; p = 0.77, and 54 vs. 60% at 3 months; p = 0.33, respectively), more patients achieved urinary continence in the immobilized group than lateral-suture group after 6 months (71 vs. 83% at 6 months; p = 0.03 and 82 vs. 96% at 12 months; p = 0.001, respectively). CONCLUSIONS: Simple suture of the bladder neck muscle layer at the vesicourethral anastomosis site to DVC led to a better urinary continence status 6 months or later after RALP.
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Laparoscopia , Complicações Pós-Operatórias/prevenção & controle , Prostatectomia/métodos , Procedimentos Cirúrgicos Robóticos , Técnicas de Sutura , Uretra/cirurgia , Bexiga Urinária/cirurgia , Incontinência Urinária/prevenção & controle , Idoso , Anastomose Cirúrgica , Humanos , Masculino , Estudos Retrospectivos , Veias/cirurgiaRESUMO
Lead (Pb) pollution in soil has become one of the most serious environmental problems, and it is more urgent in areas where acid rain is prevalent. Curing agents to solidify heavy metals in soil are efficiently applied to remediate Pb-contaminated soil. In this study, we prepared biochar, biochar loaded with nano-zero-valent iron (BC-nZVI), and biochar loaded with nano-ferroferric oxide (BC-nFe3O4), and investigated the Pb-immobilizing efficiency in contaminated soil in the condition of acid rain by them. The results showed that 8 g/kg is the best added dosage of curing agents for immobilizing Pb, which of the immobilizing efficiency of Pb were 19% (biochar), 42% (BC-nZVI), and 23% (BC-nFe3O4), respectively. Besides, the curing agents had positive effects on immobilizing Pb under acid rain condition, which could significantly reduce the content of acid extractable Pb, especially BC-nZVI (1.5%). And the immobilization efficiency of modified biochar was better than biochar, especially BC-nZVI (66%). BC-nZVI showed a more ideal effect on decreasing the leaching amount of Pb in the condition of acid rain. The results highlighted that biochar-loaded nano-iron-based materials, especially BC-nZVI, was promising and environmentally friendly materials for remediating Pb-contaminated soils, which provided scientific reference and theoretical basis for the treatment of Pb-contaminated soils around industrial sites particularly in acid rain area.
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Recuperação e Remediação Ambiental , Poluentes do Solo/análise , Carvão Vegetal , Chumbo , SoloRESUMO
A field experiment was performed to study the effects of mixed amendments, namely lime + organic fertilizer (LO), lime + organic fertilizer + calcium-magnesium phosphate fertilizer (LOC), lime + organic fertilizer + sepiolite (LOS), and lime + organic fertilizer + calcium-magnesium phosphate fertilizer + sepiolite (LOCS), on the availability and uptake of Cd from contaminated paddy soil under a rice-rape (Oryza sativa L. and Brassica napus L.) rotation system. The results showed that the grain yields of rice and rape with mixed amendment-treated were slightly influenced, in that the soil pH significantly increased while the DTPA-extractable Cd content of the soil and Cd uptake by the rice and rape were significantly reduced. The uptake of Cd by brown rice decreased significantly (p < 0.05), by 55.9-59.3% and 69.6-75.5% in the 2016 and 2017 crops, respectively, compared with that of the control (CK). The Cd uptake by rapeseeds during the 2017 season observably (p < 0.05) decreased by 38.2 and 29.6% under LO and LOC treatments, respectively. The Cd concentrations in rapeseeds were 0.11-0.18 mg kg-1 under all the treatments except LOCS treatment, which is lower than the National Standard of Pollutants in Food of China (GB 2762-2017, 0.2 mg kg-1). From both economic and food safety standpoints, rape is recommended for Cd-contaminated soil because it has a low Cd accumulation ability. The results showed that the rice-rape rotation combined with LO or LOC application was useful for reducing the Cd content in both rice and rape in Cd-contaminated soil and the effects could be sustained at least for three crop seasons.
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Brassica napus/efeitos dos fármacos , Cádmio/farmacocinética , Fertilizantes , Oryza/efeitos dos fármacos , Poluentes do Solo/farmacocinética , Agricultura/métodos , Disponibilidade Biológica , Brassica napus/metabolismo , Cádmio/análise , Cálcio , Compostos de Cálcio , China , Produtos Agrícolas/efeitos dos fármacos , Produtos Agrícolas/metabolismo , Compostos de Magnésio , Silicatos de Magnésio , Oryza/metabolismo , Óxidos , Fosfatos , Solo/química , Poluentes do Solo/análiseRESUMO
On account of the potential in immobilizing metals and improving soil environment, various biochar materials have been extensively applied in environmental remediation. The purpose of this experiment was to evaluate the effect of modified coconut shell biochar (MCSB) on the availability of metals and soil biological activity in multi-metals (cadmium (Cd), nickel (Ni) and zinc (Zn)) contaminated soil. MCSB was obtained from coconut shell biochar (CSB) by hydrochloric acid pickling and ultrasonication, which has significantly improved its surface functional groups and microcosmic pore structure. Sandy soil samples were incubated at 25⯰C amended with MCSB or CSB by 0%, 2.5% and 5% addition for 63â¯days, respectively. The results showed that the acid soluble Cd, Ni and Zn decreased by 30.1%, 57.2% and 12.7%, respectively, in groups with 5% MCSB addition, which indicated MCSB had a better effect on immobilizing metals compared with CSB. In addition, higher soil biological activities were detected in different treatments compared with control (CK). Especially, the maximum bacterial number was found in 5% MCSB treatment, which increased by 149.43% compared with CK. Accordingly, our results suggested that MCSB could be used as an ameliorant to immobilize heavy metals in contaminated soils and improve soil physicochemical and biological properties.
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α-Amylase from Anoxybacillus sp. SK3-4 (ASKA) is a thermostable enzyme that produces a high level of maltose from starches. A truncated ASKA (TASKA) variant with improved expression and purification efficiency was characterized in an earlier study. In this work, TASKA was purified and immobilized through covalent attachment on three epoxide (ReliZyme EP403/M, Immobead IB-150P, and Immobead IB-150A) and an amino-epoxide (ReliZyme HFA403/M) activated supports. Several parameters affecting immobilization were analyzed, including the pH, temperature, and quantity (mg) of enzyme added per gram of support. The influence of the carrier surface properties, pore sizes, and lengths of spacer arms (functional groups) on biocatalyst performances were studied. Free and immobilized TASKAs were stable at pH 6.0-9.0 and active at pH 8.0. The enzyme showed optimal activity and considerable stability at 60 °C. Immobilized TASKA retained 50% of its initial activity after 5-12 cycles of reuse. Upon degradation of starches and amylose, only immobilized TASKA on ReliZyme HFA403/M has comparable hydrolytic ability with the free enzyme. To the best of our knowledge, this is the first report of an immobilization study of an α-amylase from Anoxybacillus spp. and the first report of α-amylase immobilization using ReliZyme and Immobeads as supports.
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Anoxybacillus/enzimologia , Proteínas de Bactérias/química , Enzimas Imobilizadas/química , alfa-Amilases/química , Estabilidade Enzimática , Temperatura Alta , Concentração de Íons de HidrogênioRESUMO
The rescuer often has to deal with patients who have suffered trauma to the bone , including heads, spine, lower and upper limbs. Serious injuries or multiorgan grudges are a frequent result of communicative cases, and a fast but accurate examination is a condition of the success of a rescue operation, putting the preliminary diagnosis and implementing real rescue activities. Delays in a rescue operation or the lack appropriate the equipment is threatening the patient with the permanent disability or even a loss of life. It is important so that Teams of the Medical Rescue, the Aviation emergency ambulance service, individuals of the State Fire Service and Hospital accident wards have an equipment which will be compatible. With equipment which without no dilemmas will be used according to assigning him without anxiety that the use is equaling for loss of possessions or the exchange on worse or dirty. An next amendment to a bill about the National Medical rescue should obligatorily have regulations on the availability and compatibilities of equipment among others used in immobilizing traumatic and the National Health Fund should develop tough equipment principles in contracting services. All remarks and amendments to the provisions concerning the compatibility of equipment used in grudges they will have an intense influence on the quality of granted benefits in saving the health and the human life as well as will improve the comfort of the work of the paramedic.
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Imobilização , Ferimentos e Lesões , Serviços Médicos de Emergência , HumanosRESUMO
In order to improve catalytic activity, increase recycling times, reduce use cost for enzyme, superparamagnetic carboxymethyl chitosan/sodium alginate nanosphere (SM/CMC/SA) has been synthesized via an improved hydrothermal method, molecular self-assembly technology, electrostatic interaction and amide linkage. Its mean diameter was 65nm, zeta potential was -36.9mV and BET was 53.8m(2)/g. α-Amylase was selected as a simulation object to manufacture an immobilized enzyme (SM/CMC/CA/α-Amy), and its catalytic activity, release behavior, reusability and stability were researched. Immobilization increased 4.67 times to catalytic activity, slowed down release rate and improved reusable performance. SM/CMC/CA/α-Amy showed higher activity over a wider pH range, especially in strong acidic and alkaline environments. The thermal stability and storage stability were improved remarkably too. All these results indicated that SM/CMC/SA was an ideal carrier for immobilizing enzyme.
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Alginatos/química , Quitosana/análogos & derivados , Enzimas Imobilizadas/química , Imãs/química , Nanosferas/química , alfa-Amilases/química , Biocatálise , Técnicas de Química Sintética , Quitosana/química , Enzimas Imobilizadas/metabolismo , Ácido Glucurônico/química , Ácidos Hexurônicos/química , Concentração de Íons de Hidrogênio , alfa-Amilases/metabolismoRESUMO
Most of the health benefits of fish oil can be attributed to the presence of omega-3 fatty acids like Docosahexenoic acid (DHA) and Eicosapentaenoic acid (EPA). There are few dietary sources of EPA and DHA other than oily fish. EPA and DHA have great potential effect on human health. In this research, Supercritical carbon dioxide (scCO2) extracted mackerel oil was reacted by enzyme at different systems to improve the EPA and DHA. Different types of immobilize enzyme TL-IM, RM-IM, Novozyme 435 were assessed for improving PUFAs. Best result was found at non-pressurized system using TL-IM. Reacted oil particle were obtained with polyethylene glycol by gas saturated solution process (PGSS). Different parameters like temperature, pressure, agitation speed and nozzle size effect on particle formulation were observed. SEM and PSA analysis showed, small size non spherical particles were obtained. It was found that after particle formation poly unsaturated fatty acids (PUFAs) were present in particle as same in oil. PUFAs release from particle was almost linear against constant time duration. Oil quality in particle not change significantly, in this contrast this study will be helpful for food and pharmaceutical industry to provide high EPA and DHA containing powder.
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The amendment of contaminated soil with organic materials is considered to be an environmentally friendly technique to immobilize heavy metal(loid)s and minimize their subsequent bioaccumulation in plants. This study focuses on the effects of different amendment techniques, such as the use of activated carbons (granulated or powder) and farmyard manure at various application rates (2 and 5 %). These techniques were applied on heavy metal(loid)s such as Ni, Cr, Cd, Pb, Mn, Cu, Zn, Fe, Co, and Al that were present in mine-impacted soil and caused bioaccumulation in cultivated plants. The results showed that, compared with the control, almost all the techniques significantly (P ≤ 0.01) reduced the bioavailability of heavy metal(loid)s in the amended soil. The bioaccumulation of heavy metal(loid)s in Penisitum americanum and Sorghum bicolor was significantly (P ≤ 0.01) reduced with all techniques, while Zn and Cd concentrations increased with the use of farmyard manure. Also compared with the control, plant growth was significantly decreased with the use of activated carbons, particularly with powder activated carbons, while farmyard manure (at 5 %) significantly (P ≤ 0.01) increased plant growth. Among the amendment techniques, powdered activated carbons (at 5 %) were best at reducing the bioavailability of heavy metal(loid)s in soil and plant accumulation. However, it negatively affected the growth of selected plant species.
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Carvão Vegetal/química , Esterco/análise , Metais Pesados/metabolismo , Poaceae/metabolismo , Poluentes do Solo/metabolismo , Sorghum/metabolismo , Adsorção , Biodegradação Ambiental , Metais Pesados/análise , Mineração , Desenvolvimento Vegetal , Poaceae/química , Poaceae/crescimento & desenvolvimento , Solo/química , Poluentes do Solo/análise , Sorghum/química , Sorghum/crescimento & desenvolvimentoRESUMO
N(6)-carboxymethyl-NAD (N(6)-CM-NAD) can be used to immobilize NAD onto a substrate containing terminal primary amines. We previously immobilized N(6)-CM-NAD onto sepharose beads and showed that Thermotoga maritima glycerol dehydrogenase could use the immobilized cofactor with cofactor recycling. We now show that Saccharomyces cerevisiae alcohol dehydrogenase, rabbit muscle L-lactate dehydrogenase (type XI), bovine liver L-glutamic dehydrogenase (type III), Leuconostoc mesenteroides glucose-6-phosphate dehydro-genase, and Thermotoga maritima mannitol dehydrogenase are active with soluble N(6)-CM-NAD. The products of all enzymes but 6-phospho-D-glucono-1,5-lactone were formed when sepharose-immobilized N(6)-CM-NAD was recycled by T. maritima glycerol dehydrogenase, indicating that N(6)-immobilized NAD is suitable for use by a variety of different dehydrogenases. Observations of the enzyme active sites suggest that steric hindrance plays a greater role in limiting or allowing activity with the modified cofactor than do polarity and charge of the residues surrounding the N(6)-amine group on NAD.
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NAD/metabolismo , Oxirredutases/metabolismo , Sefarose/metabolismo , Álcool Desidrogenase/metabolismo , Animais , Bovinos , Glutamato Desidrogenase/metabolismo , L-Lactato Desidrogenase/metabolismo , NAD/análogos & derivados , Coelhos , Desidrogenase do Álcool de Açúcar/metabolismoRESUMO
This research was aimed to develop the lysozyme immobilized ion-exchange nanofiber mats for wound healing. To promote the healing process, the PSSA-MA/PVA and PAMA ion-exchange nanofiber mats were fabricated to mimic the extracellular matrix structure using electrospinning process followed by thermally crosslinked. Lysozyme was immobilized on the ion-exchane nanofibers by an adsorption method. The ion-exchange nanofibers were investigated using SEM, FTIR and XRPD. Moreover, the lysozyme-immobilized ion-exchange nanofibers were further investigated for lysozyme content and activity, lysozyme release and wound healing activity. The fiber diameters of the mats were in the nanometer range. Lysozyme was gradually absorbed into the PSSA-MA/PVA nanofiber with higher extend than that is absorbed on the PAMA/PVA nanofiber and exhibited higher activity than lysozyme-immobilized PAMA/PVA nanofiber. The total contents of lysozyme on the PSSA-MA/PVA and PAMA/PVA nanofiber were 648 and 166 µg/g, respectively. FTIR and lysozyme activity results confirmed the presence of lysozyme on the nanofiber mats. The lysozyme was released from the PSSA-MA/PVA and PAMA/PVA nanofiber in the same manner. The lysozyme-immobilized PSSA-MA/PVA nanofiber mats and lysozyme-immobilized PAMA/PVA nanofiber mats exhibited significantly faster healing rate than gauze and similar to the commercial antibacterial gauze dressing. These results suggest that these nanofiber mats could provide the promising candidate for wound healing application.
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To assess the global translational level of mammalian cells (see similar protocols for bacteria and yeast on Analysis of polysomes from bacteria, Polysome Profile Analysis - Yeast and Polysome analysis for determining mRNA and ribosome association in Saccharomyces cerevisiae).