Sci Rep. 2026 Jul 3. doi: 10.1038/s41598-026-60806-1. Online ahead of print.
ABSTRACT
Deep eutectic solvents (DESs) are promising green media for biocatalysis, yet their application in pyruvate decarboxylase (PDC)-mediated phenylacetylcarbinol (PAC) biotransformation with product separation remains limited. This study screened nine DESs using frozen-thawed whole cells (FT-WHC) of Candida magnoliae (C. mag.), followed by evaluation of water content and DES to phosphate buffer ratios. Glycerol-based DES resulted in significantly higher (p ≤ 0.05) volumetric PDC activity and PAC productivity than other DESs. Choline chloride: glycerol (ChCl: Gly (1:2) 20% (v/v) H2O) achieved the highest overall [PAC] of 148.2 ± 0.3 mM. Adding 100% (v/v) water decreased stability of volumetric PDC activity, but doubled PAC productivity, and reduced solvent cost compared with a 20% (v/v) H2O addition. The DES-to-phosphate buffer (Pi buffer) ratio at 1:1 was optimal, while lower ratios reduced PAC production. Spontaneous formation of PAC-enriched droplets (~ 2.5 M) as a top phase indicated simplified downstream recovery. This indicates DES-based self-separation driven by polarity and product partitioning. Overall, ChCl: Gly (1:2) with 100% (v/v) H2O at a 1:1 DES: Pi buffer ratio was selected for future PAC biotransformation. These findings indicate that DESs enhance biocatalytic performance and enable integrated reaction and product separation in a single step, offering a sustainable route to biochemical production.
PMID:42399643 | DOI:10.1038/s41598-026-60806-1