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Exploring the potential of utilizing CO2 for commercial purposes is a promising opportunity, especially in light of the growing research efforts towards CO2 capture, storage, and utilization as well as green H2 production. This review article delves into catalyst features and other technological aspects of a plausible process for the indirect conversion of CO2 into glycolic acid, which involves the following steps: CO2 capture, water electrolysis, CO2 hydrogenation to methanol, catalytic oxidation to formaldehyde, and formaldehyde carbonylation to glycolic acid. We adopt an industrial perspective to address this challenge effectively, thoroughly evaluating different processing alternatives with emphasis on the catalytic systems to optimize glycolic acid production performance. [ABSTRACT FROM AUTHOR]

Cellulases are a class of enzymes of great industrial interest that present several strategic applications. However, the high cost of enzyme production, coupled with the instabilities and complexities of proteins required for hydrolytic processes, still limits their use in several protocols. Therefore, enzyme immobilization may be an essential tool to overcome these issues. The present work aimed to evaluate the immobilization of cellulolytic enzymes of the commercial enzyme cocktail Celluclast® 1.5 L in comparison to the cellulolytic enzyme cocktail produced from the wild strain Trichoderma harzianum I14-12 in Accurel® MP1000. Among the variables studied were temperature at 40 °C, ionic strength of 50 mM, and 72 h of immobilization, with 15 m·L −1 of proteins generated biocatalysts with high immobilization efficiencies (87% for ACC-Celluclast biocatalyst and 95% for ACC-ThI1412 biocatalyst), high retention of activity, and specific activities in the support for CMCase (DNS method), FPase (filter paper method) and β-glucosidase (p-nitrophenyl-β-D-glucopyranoside method). Presenting a lower protein concentration (0.32 m·L−1) than the commercial Celluclast® 1.5 L preparation (45 m·L−1), the ACC-ThI1412-derived immobilized biocatalyst showed thermal stability at temperatures higher than 60 °C, maintaining more than 90% of the residual activities of FPase, CMCase, and β-glucosidase. In contrast, the commercial-free enzyme presented a maximum catalytic activity at only 40 °C. Moreover, the difference in molecular weight between the component enzymes of the extract was responsible for different hydrophobic and lodging interactions of proteins on the support, generating a robust and competitive biocatalyst. [ABSTRACT FROM AUTHOR]

The high demand for food and energy imposed by the increased life expectancy of the population has driven agricultural activity, which is reflected in the larger quantities of agro-industrial waste generated, and requires new forms of use. Brazil has the greatest biodiversity in the world, where corn is one of the main agricultural genres, and where over 40% of the waste generated is from cobs without an efficient destination. With the aim of the valorization of these residues, we proposed to study the immobilization of laccase from Aspergillus spp. (LAsp) in residual corn cob and its application in the degradation of Remazol Brilliant Blue R (RBBR) dye. The highest yields in immobilized protein (75%) and residual activity (40%) were obtained at pH 7.0 and an enzyme concentration of 0.1 g.mL−1, whose expressed enzyme activity was 1854 U.kg−1. At a temperature of 60 °C, more than 90% of the initial activity present in the immobilized biocatalyst was maintained. The immobilized enzyme showed higher efficiency in the degradation (64%) of RBBR dye in 48 h, with improvement in the process in 72 h (75%). The new biocatalyst showed operational efficiency during three cycles, and a higher degradation rate than the free enzyme, making it a competitive biocatalyst and amenable to industrial applications. [ABSTRACT FROM AUTHOR]

The development of the future French and European bioeconomies will involve developing new green chemical processes in which catalytic transformations are key. The VAALBIO team (valorization of alkanes and biomass) of the UCCS laboratory (Unité de Catalyse et Chimie du Solide) are working on various catalytic processes, either developing new catalysts and/or designing the whole catalytic processes. Our research is focused on both the fundamental and applied aspects of the processes. Through this review paper, we demonstrate the main topics developed by our team focusing mostly on oxygen- and hydrogen-related processes as well as on green hydrogen production and hybrid catalysis. The social impacts of the bioeconomy are also discussed applying the concept of the institutional compass. [ABSTRACT FROM AUTHOR]

BACKGROUND In this work, lipase B from Candida antarctica (CaLB) was immobilized on Purolite® ECR8205F, Purolite® ECR8214F and Immobead® IB150 P epoxy resins with no modification to their surfaces. Biocatalysts were evaluated for thermal stability and applied in reactions of hydrolysis, esterification and the synthesis of glyceryl carbonate by transesterification with dimethyl-carbonate both with glycerol and Macauba oil as well as dynamic kinetic resolution of α-methylbenzylamine, all of them compared with commercial Novozyme 435®. RESULTS Protein desorption of the biocatalysts with Triton X-100 showed that lipase was immobilized by covalent single-bond type binding. The immobilization efficiencies were 55.1% for the biocatalyst 8205, 57.1% for 8214, and 14.9 for the 150P, demonstrating the intense effect of surface and material composition on lipase immobilization. The biocatalysts also showed higher initial velocities of esterification and hydrolysis reactions as well as higher thermal stability than Novozyme 435®. On glycerol carbonate synthesis, conversion of 97% and selectivity higher than 99% was demonstrated by enzyme 8214, similar to Novozyme 435®. On kinetic dynamic resolution, conversions higher than 94% and and enantiomeric excesses greater than 90% were also depicted. CONCLUSION Compared with commercial preparation Novozyme 435®, the novel biocatalysts obtained by immobilization on new epoxy resins demonstrated protein loads about 10-fold lower and higher specific activity. In all reactions performed, competitive performances were found, demonstrating high potential for industrial applications. © 2017 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

The high life expectancy of the world population provokes increase in demand for food and energy. As a result, the intense industrialization and the application of fossil sources is responsible for high levels of CO2 emission and waste generation. To mitigate the CO2 emission a practical solution at the very short term is urgently needed. The capture of CO2 and its application in chemical processes for the valorization of residual biomass are of great importance nowadays. The application of CO2 in the selective carboxylation of furoic acid for the production of 2,5-furandicarboxylic acid (FDCA), a bio-based monomer, has been an important step towards obtaining biopolymers to replace petroleum-based plastics such as polyethylene terephthalate (PET). In this project report, we discuss on the current challenges for obtaining the 2,5-FDCA precursor from the furfural in two main routes involving oxidation and carboxylation via heterogeneous catalysis. We present the main objectives and discuss the importance of this research for the development of more sustainable processes. [ABSTRACT FROM AUTHOR]

During recent decades, the use of enzymes or chemoenzymatic cascades for organic chemistry has gained much importance in fundamental and industrial research. Moreover, several enzymatic and chemoenzymatic reactions have also served in green and sustainable manufacturing processes especially in fine chemicals, pharmaceutical, and flavor/fragrance industries. Unfortunately, only a few processes have been applied at industrial scale because of the low stabilities of enzymes along with the problematic processes of their recovery and reuse. Immobilization and co-immobilization offer an ideal solution to these problems. This review gives an overview of all the pathways for enzyme immobilization and their use in integrated enzymatic and chemoenzymatic processes in cascade or in a one-pot concomitant execution. We place emphasis on the factors that must be considered to understand the process of immobilization. A better understanding of this fundamental process is an essential tool not only in the choice of the best route of immobilization but also in the understanding of their catalytic activity. [ABSTRACT FROM AUTHOR]

Biocatalytic transesterification is commonly carried out employing lipases in anhydrous organic solvents since hydrolases usually prefer hydrolysis over acyl transfer in bulk water. However, some promiscuous acyltransferases can catalyze acylation in an aqueous solution. In this study, a rational design was performed to enhance the acyltransferase selectivity and substrate scope of the Pyrobaculum calidifontis VA1 esterase (PestE). PestE wild type and variants were applied for the acylation of monoterpene alcohols. The mutant PestE_I208A is selective for (–)-menthyl acetate (E-Value = 55). Highly active acyltransferases were designed, allowing for complete conversion of (–)-citronellol to citronellyl acetate. Additionally, carvacrol was acetylated but with lower conversions. To the best of our knowledge, this is the first example of the biocatalytic acylation of a phenolic alcohol in bulk water. In addition, a high citronellol conversion of 92% was achieved with the more environmentally friendly and inexpensive acyl donor ethyl acetate using PestE_N288F as a catalyst. PestE_N288F exhibits good acyl transfer activity in an aqueous medium and low hydrolysis activity at the same time. Thus, our study demonstrates an alternative synthetic strategy for acylation of compounds without organic solvents. [ABSTRACT FROM AUTHOR]

2,5-furandicarboxylic acid (2,5-FDCA) is a biomass derivate of high importance that is used as a building block in the synthesis of green polymers such as poly(ethylene furandicarboxylate) (PEF). PEF is presumed to be an ideal substitute for the predominant polymer in industry, the poly(ethylene terephthalate) (PET). Current routes for 2,5-FDCA synthesis require 5-hydroxymethylfurfural (HMF) as a reactant, which generates undesirable co-products due to the complicated oxidation step. Therefore, direct CO2 carboxylation of furoic acid salts (FA, produced from furfural, derivate of inedible lignocellulosic biomass) to 2,5-FDCA is potentially a good alternative. Herein, we present the primary results obtained on the carboxylation reaction of potassium 2-furoate (K2F) to synthesize 2,5-FDCA, using heterogeneous catalysts. An experimental setup was firstly validated, and then several operation conditions were optimized, using heterogeneous catalysts instead of the semi-heterogeneous counterparts (molten salts). Ag/SiO2 catalyst showed interesting results regarding the K2F conversion and space–time yield of 2,5-FDCA. [ABSTRACT FROM AUTHOR]

As a consequence of intense industrialization in the last few decades, the amount of agro-industrial wastes has increasing, where new forms of valorization are crucial. In this work, five residual biomasses from Maranhão (Brazil) were investigated as supports for immobilization of lipase from Thermomyces lanuginosus (TLL). The new biocatalysts BM-TLL (babaçu mesocarp) and RH-TLL (rice husk) showed immobilization efficiencies >98% and hydrolytic activities of 5.331 U g−1 and 4.608 U g−1, respectively, against 142 U g−1 by Lipozyme® TL IM. High esterification activities were also found, with 141.4 U g−1 and 396.4 U g−1 from BM-TLL and RH-TLL, respectively, against 113.5 U g−1 by TL IM. Results of porosimetry, SEM, and BET demonstrated BM and RH supports are mesoporous materials with large hydrophobic area, allowing a mixture of hydrophobic adsorption and confinement, resulting in hyperactivation of TLL. These biocatalysts were applied in the production of hexyl laurate, where RH-TLL was able to generate 94% conversion in 4 h. Desorption with Triton X-100 and NaCl confirmed that new biocatalysts were more efficient with 5 times less protein than commercial TL IM. All results demonstrated that residual biomass was able to produce robust and stable biocatalysts containing immobilized TLL with better results than commercial preparations. [ABSTRACT FROM AUTHOR]