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A photochemoenzymatic halodecarboxylation of ferulic acid was achieved using vanadate-dependent chloroperoxidase as (bio)catalyst and oxygen and organic solvent as sole stoichio-metric reagents in a biphasic system. Performance and selectivity were improved through a phase transfer catalyst, reaching a turnover number of 660.000 for the enzyme.

A novel strategy for improving wet resistance and bonding properties of starch-based adhesives using enzymatically polymerized lignosulfonates and carboxylic acids as additives was developed. Therefore, lignosulfonates were polymerized by laccase to a molecular weight of 750 kDa. Incorporation of low concentrations (up to 1% of the starch weight) of 1,2,3,4-butanetetracarboxylic acid (BTCA) led to further improvement on the properties of the adhesives, while addition of greater amounts of BTCA led to a decrease in the properties measured due to large viscosity increases. Great improvements in wet-resistance from 22 to 60 min and bonding times (from 30 to 20 s) were observed for an adhesive containing 8% enzymatically polymerized lignin and 1% BTCA. On the other hand, the addition of citric acid (CA) deteriorated the properties of the adhesives, especially when lignosulfonate was present. In conclusion, this study shows that the addition of the appropriate amount of enzymatically polymerized lignosulfonates together with carboxylic acids (namely BTCA) to starch-based adhesives is a robust strategy for improving their wet resistance and bonding times.

Lignosulfonate (LS), one of the byproducts of the paper and pulp industry, was mainly used as an energy source in the last decade until the valorization of lignin through different functionalization methods grew in importance. Polymerization using multicopper oxidase laccase (from the Myceliophthora thermophila fungus) is one of such methods, which not only enhances properties such as hydrophobicity, flame retardancy, and bonding properties but can also be used for food and possesses pharmaceutical-like antimicrobial properties and aesthetic features of materials. Appropriate downstream processing methods are needed to produce solids that allow the preservation of particle morphology, a vital factor for the valorization process. In this work, an optimization of the enzymatic polymerization via spray-drying of LS was investigated. The response surface methodology was used to optimize the drying process, reduce the polymerization time, and maximize the dried mass yield. Particles formed showed a concave morphology and enhanced solubility while the temperature sensitivity of spray-drying protected the phenol functionalities beneficial for polymerization. Using the optimized parameters, a yield of 65% in a polymerization time of only 13 min was obtained. The experimental values were found to be in agreement with the predicted values of the factors ( R 2 : 95.2% and p -value: 0.0001), indicating the suitability of the model in predicting polymerization time and yield of the spray-drying process.