Forestry and agricultural industries constitute highly relevant economic activities globally. They generate large amounts of residues rich in lignocellulose that have the potential to be valorized and used in different industrial processes. Producing renewable fuels and high-value-added compounds from lignocellulosic biomass is a key aspect of sustainable strategies and is central to the biorefinery concept. In this study, the use of biomass-derived monosaccharides for the enzymatic synthesis of sugar fatty acid esters (SFAEs) with antimicrobial activity was investigated to valorize these agro-industrial residues. With the aim to evaluate if lignocellulosic monosaccharides could be substrates for the synthesis of SFAEs, d-xylose, l-arabinose, and d-glucose, lauroyl and stearoyl monoesters were synthetized by transesterification reactions catalyzed by Lipozyme RM IM as biocatalyst. The reactions were performed using commercial d-xylose, l-arabinose, and d-glucose separately as substrates, and a 74:13:13 mixture of these sugars. The proportion of monosaccharides in the latter mixture corresponds to the composition found in hemicellulose from sugarcane bagasse and switchgrass, as previously described in the literature. Products were characterized using nuclear magnetic resonance (NMR) spectroscopy and showed that only the primary hydroxyl group of these monosaccharides is involved in the esterification reaction. Antimicrobial activity assay using several microorganisms showed that 5-O-lauroyl-d-xylofuranose and 5-O-lauroyl-l-arabinofuranose have the ability to inhibit the growth of Gram-positive bacteria separately and in the products mix. Furthermore, 5-O-lauroyl-l-arabinofuranose was the only product that exhibited activity against Candida albicans yeast, and the four tested filamentous fungi. These results suggest that sugar fatty acid esters obtained from sustainable and renewable resources and produced by green methods are promising antimicrobial agents.

Laccase from Dichostereum sordulentum was entrapped in hydrogels formed using lignocellulosic residues from bioethanol production and ionic liquids. The active hydrogel was efficient in ethinylestradiol removal.

The widespread presence of estrogenic pollutants in aquatic environments poses a significant threat to ecosystems and human health, necessitating the development of efficient and sustainable removal technologies. This study aimed to develop a cost-effective biocatalyst for estrogen biodegradation using a fungal laccase. The enzyme was produced by the native strain Dichostereum sordulentum under semi-solid-state fermentation conditions optimized using a statistical Design of Experiments. The design evaluated carbon sources (glucose/glycerol), nitrogen sources (peptone/urea), inoculum size, and Eucalyptus dunnii bark as a solid support/substrate. The resulting laccase was entrapped within a hydrogel made of lignocellulosic biopolymers derived from a second-generation bioethanol by-product. Maximum laccase production was achieved with a high concentration of peptone (12 g/L), a low amount of bark (below 2.8 g), 8.5 g/L glucose and 300 mg/flask of inoculum. The subsequent immobilized laccase achieved 98.8 ± 0.5% removal of ethinylestradiol, outperforming the soluble enzyme. Furthermore, the treatment reduced the estrogenic biological activity by more than 170-fold. These findings demonstrate that the developed biocatalyst not only valorizes an industrial by-product but also represents an effective and sustainable platform for mitigating hazardous estrogenic pollution in water.