Application of Alcohol-Salt Aqueous Biphasic System for the Recovery of Ectoine

Abstract

Ectoine is an osmoregulatory compound synthesized by halophiles which has attracted attention in the biotechnology, pharmaceuticals, and cosmetics industries due to its stabilizing and protective properties. Conventional methods for ectoine recovery are complex, costly, and often result in low yields. Therefore, there is a growing interest in exploring simple and cost-effective strategies for ectoine recovery. The aqueous biphasic system (ABS) has been employed for the recovery and purification of numerous biocompounds, but the study of low-molecular weight compounds partitioning in ABS remains limited. This study aimed to investigate the feasibility of alcohol–salt ABS for ectoine recovery from Halomonas salina DSM5928T cells. The influences of types and compositions of phase-forming components, crude load concentration, pH, and adjuvants on ectoine recovery were evaluated. Results revealed that ectoine favoured partitioning into the salt-rich bottom phase of alcohol–salt ABS owing to its inherent hydrophilic characteristic. ABS consisting of 16% (w/w) 1-propanol, 20% (w/w) sulphate at pH 6.0, 30% (w/w) crude load, and 1% (w/w) sodium chloride resulted in a partition coefficient (KE) of 9.61 ± 0.05 and a yield (YB) of 97.50% ± 0.21. A purity (PE) of 86.73% was achieved with the 1-propanol-sulphate ABS. Alcohol–salt ABS proved to be an effective approach for ectoine recovery, meeting the raising market demand for industrial applications.