Representing GENESIS group, Ebin K Baby delivered a talk on "Influence of Individual Components of Deep Eutectic Solvents on Biocatalysis".
Deep Eutectic Solvents (DESs) have emerged as promising alternatives to conventional aqueous and organic solvents due to their unique ability to combine the characteristics of both. One of their key advantages is the capacity to enhance substrate loading by increasing the solubility of hydrophobic compounds. For instance, DESs have been shown to improve the solubility of halogenated hydrocarbons, epoxides, and various pharmaceutical drugs, while simultaneously minimising undesirable side reactions. DESs are a special class of eutectic mixtures, typically formed through the interaction of hydrogen bond donors (HBDs) and hydrogen bond acceptors (HBAs), or mixtures of Lewis acids and bases. Common HBDs include urea, glycerol, ethylene glycol, and glucose, while HBAs are often ammonium- or phosphonium-based salts. A critical factor in DES formulation is ensuring a minimal acidity difference between the components to promote stable interactions. Since DESs are mixtures, it is essential to understand the individual influence of each component, especially when applied to sensitive systems such as enzymes. In our study, we investigated the impact of typical HBAs (quaternary ammonium and phosphonium compounds) and HBDs (such as glycerol and ethylene glycol) on the activity of horse liver alcohol dehydrogenase (HLADH). Notably, both ammonium and phosphonium compounds significantly enhanced HLADH activity. These findings emphasise the importance of evaluating individual components prior to selecting a specific DES formulation for biocatalytic applications.