Optimal conditions for 2-phenylethanol production from l-phenylalanine by Acinetobacter soli ANG344B

Abstract

BACKGROUND: 2-Phenylethanol (2-PE) is a valuable flavor compound renowned for its rose-like scent and widespread application in the cosmetic, perfume and food industries. While it can be naturally sourced from plants, the majority is currently produced through chemical synthesis, leading to environmental concerns. As an ecofriendly alternative, biotechnological production of 2-PE presents a promising solution, yielding a natural product. RESULTS: In this work, the newly isolated bacterium Acinetobacter soli ANG344B was used to produce 2-PE from l-phenylalanine (L-Phe), using glucose as carbon source, aiming to determine the best conditions for cellular growth and aroma production. The optimal conditions for Acinetobacter cultivation and 2-PE production were 30 °C and pH 7. Further, yeast extract proved to be a key element for 2-PE production. The concentration of L-Phe that maximizes 2-PE volumetric productivity was found to be 5 g L−1, present in the cultivation media from the beginning of the cultivation. Under these conditions 2.14 ± 0.18 g L−1 of the aroma compound was produced, which is the highest concentration obtained for a wild-type bacterium. The toxicity of 2-PE was also evaluated, revealing that cellular growth of A. soli ANG344B was adversely affected at concentrations above 1 g L−1, and beyond 4 g L−1 no cellular growth was observed. CONCLUSION: By elucidating the crucial factors affecting 2-PE production by A. soli ANG344B, we pave the way for the development of biotechnological strategies to harness its potential as a natural and sustainable aroma compound. © 2024 Society of Chemical Industry (SCI).