Any Monte Carlo research of huge vesicle morphologies in nonequilibrium surroundings

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Protic ionic liquids have been proposed as effective solvents for the selective extraction of lignin from wood. In this work, the protic ionic liquid 1-methylimidazolium chloride has been used to extract lignin at different biomass loadings, temperatures, and times to understand the influence of treatment severity on the lignin dissolution mechanism. The maximum lignin recovery (82.35 g lignin/100 g biomass lignin) was achieved at 10% (w/w) biomass loading, 135 °C, and 6 h. An increase in treatment severity leads to an acid cleavage of ether linkages, which increases the average molecular weight and thermal stability of lignins due to C-C repolymerization. HSQC-NMR analysis showed the effect of operating conditions on the predominant mechanism of lignin depolymerization. At mild conditions, there is a preferential degradation of G units (the typical depolymerization mechanism of ionic liquid treatments); but at the most severe conditions, S units are predominantly removed, as usually occurs in acidic treatments. This work contributes to better understanding the different lignin extraction mechanisms occurring with a protic ionic liquid depending on different operating conditions. Two extracellular enzymes of the SGNH hydrolase superfamily reveal highly homologous 3D structures, but act on different substrates; one is a true phospholipase A1 from Streptomyces albidoflavus (SaPLA1, EC 3.1.1.32, PDB code 4HYQ), whereas the promiscuous enzyme from Streptomyces rimosus (SrLip, EC 3.1.1.3, PDB code 5MAL) exhibits lipase, phospholipase, esterase, thioesterase, and Tweenase activities. To get insight into binding modes of phospholipid and triglyceride substrates in both enzymes and understand their chain-length preferences, we opted for computational approach based on in silico prepared enzyme-substrate complexes. Docking procedure and molecular dynamics simulations at microsecond time scale were applied. The modelled complexes of SaPLA1 and SrLip enzymes revealed substrate accommodation a) the acyl-chain attached to sn-1 position fits into the hydrophobic pocket, b) the acyl-chain attached to sn-2 position fits in the hydrophobic cleft, whereas c) the sn-3 bound acyl chain of the triglyceride or polar head of the glycerophospholipid fits into the binding groove. Moreover, our results pinpointed subtle amino acid differences in the hydrophobic pockets of these two enzymes which accommodate the acyl chain attached to sn-1 position of glycerol to be responsible for the chain length preference. Slight differences in the binding grooves of SaPLA1 and SrLip, which accommodate the acyl chain attached to sn-3 position are responsible for exclusive phospholipase and both phospholipase/lipase activities of these two enzymes, respectively. The results of modelling correlate with the experimentally obtained kinetic parameters given in the literature and are important for protein engineering that aims to obtain a variant of enzyme, which would preferably act on the substrate of interest. V.The objective of this work is to fabricate zein/fucoidan composite nanoparticles for the delivery of pterostilbene, a hydrophobic nutraceutical with diverse beneficial biological activities. Pterostilbene-encapsulated zein/fucoidan composite nanoparticles were prepared using an anti-solvent precipitation method. The fucoidan levels affected the physicochemical properties of the composite nanoparticles. When the zein to fucoidan mass ratio was 101, 51, 21, or 11, the prepared zein/fucoidan nanoparticles were stable, and these nanoparticles showed higher pterostilbene encapsulation efficiency than did zein nanoparticles. Fucoidan-stabilized zein nanoparticles exhibited globular structure with average diameters of 120-150 nm. Fourier-transform infrared spectroscopy, X-ray diffraction, and fluorescence spectrum analysis confirmed that the formation of composite nanoparticles was mainly driven by electrostatic, hydrogen-bonding, and hydrophobic interactions between pterostilbene, zein, and fucoidan. Furthermore, the photochemical stability of pterostilbene encapsulated in zein/fucoidan nanoparticles was markedly better than that of pterostilbene loaded in zein nanoparticles or unencapsulated pterostilbene. Zein/fucoidan nanoparticles provided a better controlled release of pterostilbene than did zein nanoparticles under simulated gastrointestinal conditions. Moreover, the cytotoxicity assay demonstrated that zein/fucoidan nanoparticles were nontoxic to Caco-2, HK-2, and L-02 cells. Based on our results, the zein/fucoidan nanoparticles may be a promising delivery carrier for the encapsulation, protection, and release of pterostilbene. The 3-aminopropyltriethoxysilane modified nano-carbon sphere (MNCS) was added into pectin-Ca2+ film to improve the controlled release properties of the pectin-based oral colon-specific drug delivery system (OCDDS). The FT-IR measurements indicated the successful modification of nano-carbon sphere via silylation reaction and the electrostatic interaction between the pectin molecules and MNCS in the composite film. The FE-SEM showed the pore structure when the MNCS was mingled with the pectin. The 5-fluorouracil (5-FU) was employed as the drug model and the controlled release properties of the corresponding OCDDSs were determined. The values of the encapsulation efficiency ranged from 30.1% to 52.6%. All composite film based OCDDSs presented higher encapsulation efficiency than single pectin-Ca2+ based OCDDS. The drug release studies emerged that almost all the OCDDSs from composite films presented better release properties than single pectin-Ca2+ based OCDDS. The sample C revealed best release performance with the cumulative release rate of 32.17%, 22.77% and 63.89% in the simulated gastric fluid, small intestinal fluid and colon fluid, respectively. In addition, the kinetics studies were performed to analyze the release data. The cytotoxicity assay indicated good biocompatibility of the composite carriers. selleck chemical V.Plant-based expression system has many potential advantages to produce biopharmaceuticals, but plants cannot be directly used to express human glycoproteins because of their differences in glycosylation abilities from mammals. To exploit plant-based expression system for producing recombinant human erythropoietin (rhuEPO), we glycoengineered tobacco plants by stably introducing seven to eight mammalian genes including a target human EPO into tobacco in order to generate capacities for β1,4-galactosylation, bisecting N-acetylglucosamine (GlcNAc) and sialylation. Wild type human β1,4-galactosyltransferase gene (GalT) or a chimeric GalT gene (ST/GalT) was co-expressed to produce rhuEPO bearing β1,4-galactose-extended N-glycan chains as well as compare their β1,4-galactosylation efficiencies. Five mammalian genes encoding enzymes/transporter for sialic acid biosynthesis, transport and transfer were co-expressed to build sialylation capacity in plants. The human MGAT3 was co-expressed to produce N-glycan chains with bisecting GlcNAc.