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Rheological properties of hydrophobized hydrolysis lignin dispersions in tank oil, diesel fuel, and industrial oil were under study. It was found that at the hydrolysis lignin content of more than 20 wt. %, a coagulation-thixotropic structure with a pseudoplastic flow pattern is formed. The parameters of structure formation calculated within the theory of elastic flocks made it possible to characterize dispersions in diesel fuel as least structured. In accordance with the theory of diffusion-limited aggregation, a computer model of the aggregate of hydrolytic lignin particles in diesel fuel was calculated and its internal structure was established using the proposed method of computer analysis of digital photographs. Machine learning was used to predict the optimal conditions for the production of mesoporous activated carbons from hydrolysis lignin. Experimentally obtained carbons are characterized by total pore volume of (0.95 ± 0.05) cm3/g and BET surface area of (1700 ± 85) m2/g, that corresponds to the predicted parameters.

| openaire: EC/H2020/720303/EU//Zelcor Funding Information: This work was funded by the Bio Based Industry Joint Undertaking under the European Union's Horizon 2020 research and innovation programme within the Zelcor project (under the grant number No 720303 ), part of the COFILI project (grant number D201550245 ) for AFM measurements funded by the Grand Est Region and the European FEDER Programme and the Lignoxyl project for EPR measurements supported by the Agence Nationale de la Recherche (ANR) through the Carnot Institutes 3BCAR ( www.3bcar.fr ) and Qualiment ( https://qualiment.fr/ ) (no. 3 no. 19-CARN-001-01 and no. 16-CARN 001-01). The EPR data in this manuscript were obtained using equipment supported jointly by the French National Ministry of Research (PPF IRPE), the "Fondation pour la Recherche Médicale" (FRM DGE20061007745), and the CNRS (Department of Chemistry and Life Sciences). The IJPB benefits from the support of the LabEx Saclay Plant Sciences-SPS (ANR-10-LABX-552 0040-SPS). Funding Information: This work was funded by the Bio Based Industry Joint Undertaking under the European Union's Horizon 2020 research and innovation programme within the Zelcor project (under the grant number No 720303), part of the COFILI project (grant number D201550245) for AFM measurements funded by the Grand Est Region and the European FEDER Programme and the Lignoxyl project for EPR measurements supported by the Agence Nationale de la Recherche (ANR) through the Carnot Institutes 3BCAR (www.3bcar.fr) and Qualiment (https://qualiment.fr/) (no. 3 no. 19-CARN-001-01 and no. 16-CARN 001-01). The EPR data in this manuscript were obtained using equipment supported jointly by the French National Ministry of Research (PPF IRPE), the ?Fondation pour la Recherche M?dicale? (FRM DGE20061007745), and the CNRS (Department of Chemistry and Life Sciences). The IJPB benefits from the support of the LabEx Saclay Plant Sciences-SPS (ANR-10-LABX-552 0040-SPS). Publisher Copyright: © 2021 The Authors Copyright: Copyright2021 Elsevier B.V., All rights reserved. ; This study investigated the relationships between lignin molecular and supramolecular structures and their functional properties within cellulose-based solid matrix, used as a model biodegradable polymer carrier. Two types of derivatives corresponding to distinct structuration levels were prepared from a single technical lignin sample (PB1000): phenol-enriched oligomer fractions and colloidal nanoparticles (CLP). The raw lignin and its derivatives were formulated with cellulose nanocrystals or nanofibrils to prepare films by chemical oxidation or pressure-assisted filtration. The films were tested for their water and lignin retention capacities, radical scavenging capacity (RSC) and antimicrobial properties. A structural investigation was performed by infrared, electron paramagnetic resonance spectroscopy and microscopy. The composite morphology and performance were controlled by both the composition and structuration level of lignin. Phenol-enriched oligomers were the compounds most likely to interact with cellulose, leading to the smoothest film surface. Their RSC in film was 4- to 6-fold higher than that of the other samples. The organization in CLP led to the lowest RSC but showed capacity to trap and stabilize phenoxy radicals. All films were effective against S. aureus (gram negative) whatever the lignin structure. The results show the possibility to tune the performances of these composites by exploiting lignin multi-scale structure. ; Peer reviewed

[Background] The genome of Pleurotus ostreatus, an important edible mushroom and a model ligninolytic organism of interest in lignocellulose biorefineries due to its ability to delignify agricultural wastes, was sequenced with the purpose of identifying and characterizing the enzymes responsible for lignin degradation. ; [Results] Heterologous expression of the class II peroxidase genes, followed by kinetic studies, enabled their functional classification. The resulting inventory revealed the absence of lignin peroxidases (LiPs) and the presence of three versatile peroxidases (VPs) and six manganese peroxidases (MnPs), the crystal structures of two of them (VP1 and MnP4) were solved at 1.0 to 1.1 Å showing significant structural differences. Gene expansion supports the importance of both peroxidase types in the white-rot lifestyle of this fungus. Using a lignin model dimer and synthetic lignin, we showed that VP is able to degrade lignin. Moreover, the dual Mn-mediated and Mn-independent activity of P. ostreatus MnPs justifies their inclusion in a new peroxidase subfamily. The availability of the whole POD repertoire enabled investigation, at a biochemical level, of the existence of duplicated genes. Differences between isoenzymes are not limited to their kinetic constants. Surprising differences in their activity T50 and residual activity at both acidic and alkaline pH were observed. Directed mutagenesis and spectroscopic/structural information were combined to explain the catalytic and stability properties of the most interesting isoenzymes, and their evolutionary history was analyzed in the context of over 200 basidiomycete peroxidase sequences. ; [Conclusions] The analysis of the P. ostreatus genome shows a lignin-degrading system where the role generally played by LiP has been assumed by VP. Moreover, it enabled the first characterization of the complete set of peroxidase isoenzymes in a basidiomycete, revealing strong differences in stability properties and providing enzymes of biotechnological interest. ; This work was supported by the PEROXICATS (KBBE-2010-4-265397) and INDOX (KBBE-2013-7-613549) grants of the European Union (to ATM), by grants BIO2011-26694 (to FJR-D) and BFU2011-24615 (to AR) of the Spanish Ministry of Economy and Competitiveness (MINECO), and by US DOE grant DE-AI02-07ER64480 (to KEH). The work conducted by the US DOE JGI is supported by the Office of Science of the US DOE under contract number DE-AC02-05CH11231. AG Pisabarro (Public University of Navarre, Pamplona, Spain) is acknowledged for coordinating the P. ostreatus genome project. We thank Michael D Mozuch for assistance with the lignin depolymerization studies. EF-F acknowledges a Junta de Ampliación de Estudios fellowship of the CSIC, co-funded by the European Social Fund, and FJR-D acknowledges a MINECO Ramón y Cajal contract. ; Peer Reviewed