A simple method to produce stable aqueous dispersions of spherical anionic or cationic lignin nanoparticles from softwood kraft was developed.

Abstract Cellobiohydrolase I (CBHI) of Trichoderma reesei has two functional domains, a catalytic core domain and cellulose binding (CBD). The structure the CBD reveals distinct faces, one which is flat other rough. Several fungal cellulolytic enzymes have similar two‐domain structures, in CBDs show conserved primary structure. Here we evaluated contributions amino acids CBHI to its cellulose. Binding isotherms were determined for set six synthetic analogues substituted. Two‐dimensional NMR...

Proteins and certain carbohydrates contain phenolic moieties, which are potential sites for modification of the function biopolymers. In this study, capability two different fungal oxidative enzymes, laccase from Trametes hirsuta (ThL) tyrosinase Trichoderma reesei (TrT), to catalyze formation hetero-cross-linking between tyrosine side chains α-casein acids hydrolyzed oat spelt xylan (hOSX) was studied. Formation reaction products followed by size exclusion chromatography (SEC), fluorescence...

Laccase‐catalyzed polymerization of tyrosine and tyrosine‐containing peptides was studied in the presence absence ferulic acid (FA). Advanced spectroscopic methods such as MALDI‐TOF MS, EPR, FTIR microscopy HPLC‐fluorescence, well more conventional analytical tools: oxygen consumption measurements SDS/PAGE were used reaction mechanism studies. Laccase found to oxidize peptides, with consequent compounds. The covalent linkage connecting compounds be an ether bond. Only small amounts...

Coating of colloidal lignin particles (CLPs), or nanoparticles (LNPs), with proteins was evaluated in order to establish a safe, self-assembly mediated modification technique tune their surface chemistry. Gelatin and poly- l-lysine formed the most pronounced protein corona on CLP surface, as determined by dynamic light scattering (DLS) zeta potential measurements. Spherical morphology individual coated CLPs confirmed transmission electron (TEM) atomic force (AFM) microscopy. A mechanistic...

Cross-linked and decolorized lignin nanoparticles (LNPs) were prepared enzymatically chemically from softwood Kraft lignin. Colloidal particles (CLPs, ca. 200 nm) in a non-malodorous aqueous dispersion could be dried redispersed tetrahydrofuran (THF) or water retaining their stability i.e. spherical shape size. Two fungal laccases, Trametes hirsuta (ThL) Melanocarpus albomyces (MaL) used the cross-linking reactions. Reactivity of ThL MaL on Lignoboost™ LNPs was confirmed by high performance...

Laccase-catalyzed oligomerization of proteins was studied using Trametes hirsuta laccase (ThL) and coactosin as a model system. The reaction mechanism elucidated free amino acids the tripeptide Gly-Leu-Tyr substrates. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) high-performance liquid chromatography (HPLC) well oxygen consumption measurements SDS-PAGE were used to study reactions. Of 15 selected acids, ThL found oxidize tryptophan (Trp),...

In this study the oxidative polymerization of different lignins, i.e. Flax Soda lignin, Spruce EMAL, and Eucalyptus Dioxane lignin by Trametes hirsuta laccase was compared. Initially structures lignins were compared Fourier transform infrared spectroscopy. The reactivity with types in absence mediators examined verified oxygen consumption measurements. molecular weight distributions treated untreated determined two size exclusion chromatography methods. Furthermore, potential matrix-assisted...

Lignin has interesting functionalities to be exploited in adhesives for medicine, foods and textiles. Nanoparticles (NPs) < 100 nm coated with poly (L-lysine), PL poly(L-glutamic acid) PGA were prepared from the laccase treated lignin coat nanocellulose fibrils (CNF) heat. NPs ca. 300 prepared, β-casein cross-linked transglutaminase (Tgase) agglutinate chamois. Size exclusion chromatography (SEC) Fourier-transform infrared (FTIR) spectroscopy used characterize polymerized lignin, while...

Lignins are important biopolymers that can be converted into value-added materials by enzymatic treatments. However, the heterogeneity of lignin polymer makes it a challenging material to modify. Thus, chemical fractionation was used obtain lignins with high homogeneity in order assess their biotechnological utilization. Commercial Alcell, birch organosolv lignins, and steam-exploded pine eucalypt were sequentially fractionated ether, ether/acetone 4:1 (v:v), acetone. All fractions...

Suberin is present in the underground parts of vegetables and bark trees. Characterization suberin structure its polyphenolic component have been hampered by insolubility polymers. Thus, enzymatically isolated extractive free enriched fraction from potato, Solanum tuberosum var. Nikola, chemically further fractionated phenolics were characterized solid state FTIR, DSC, elemental analysis to identify groups verify success isolation. For MW quantitative determination groups, polymers...

The solution structure of a synthetic 38‐residue cellulose‐binding domain (CBD) endoglucanase I from Trichoderma reesei (CBD EGI ) was determined by two‐dimensional 1 H‐NMR spectroscopy. 100 structures were generated total 599 NOE derived distance restraints and 28 φ 14 χ dihedral angle restraints. For the final set 19 selected structures, rms deviation about mean 0.83 ± 0.26 Å for all atoms 0.50 0.22 backbone atoms. CBD very similar to that cellobiohydrolase T. CBHI ). trace followed...

Most Trichoderma reesei cellulases consist of a catalytic and cellulose binding domain (CBD) joined by linker. We have used cellohexaose as model compound for the glucose chain to investigate interaction between soluble enzyme cellulose. The family I CBDs was studied NMR spectroscopy. cause line broadening effects decreasing T 2 relaxation times certain resonances, whereas there are no in presence mutant which binds weakly Yet it remains uncertain how well cellooligosaccharide mimics CBD

Abstract Modified wood fibres open new perspectives to create value-added products based on renewable raw materials. An interesting option is the targeted modification of fibre surfaces by oxidative enzymes. This two-stage functionalisation method consists enzymatic activation followed addition radicalised compounds reacting preferentially radical coupling. In this work, bleached and unbleached softwood TMPs with laccase isolated from Trametes hirsuta was studied. The formation stability...