Assessment of in situ product recovery techniques to enhance 2-phenylethanol production by Acinetobacter soli ANG344B

The 2-phenylethanol (2-PE) production process by the newly isolated Acinetobacter soli ANG344B is limited by product toxicity. To overcome this limitation and enhance 2-PE production process, various alternatives based in in situ product removal (ISPR) approaches were evaluated. The approaches selected for assessment were gas stripping using the air supplied to the bioreactor, liquid-liquid extraction and adsorption. Adsorption was found to be the most promising approach to increase 2-PE production. Amberlite XAD 4 was chosen from the different adsorbents tested since it has high affinity for 2-PE, being able to adsorb 205.8 ± 8.1 mg_2-PE/g_{dry resin}. In a batch cultivation process, in presence of 3 % (dry w/v) of Amberlite XAD 4, A. soli ANG344B was able to produce 6.99 ± 0.06 g/L of 2-PE with a volumetric productivity of 0.17 ± 0.00 g/L.h, which represents an improvement of 3.3-fold. To the best of our knowledge, this is the highest 2-PE production reported for a wild-type bacteria. These findings highlight the potential of Acinetobacter soli ANG344B as 2-PE producer, contributing to the development of natural 2-PE production process.