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Abstract

Fourteen yeast strains were screened for production of 2-phenylethanol from L-phenylalanine with molasses as carbon source. Up to 1 g 2-phenylethanol l-1 was obtained. Using oleyl alcohol as a second phase for in situ product removal to enhance the production of 2-phenylethanol increased the yield to about 3 g 2-phenylethanol l-1 at 35 degrees C. The most productive strains were Kluyveromyces marxianus CBS 600 and CBS 397.

Yarrowia lipolytica: the novel and promising 2-phenylethanol producer

“…Thus, it appeared that the ability to produce 2-PE at the detectable level is not uniform among these Y. lipolytica strains and the efficiency of the production is strain-dependent. This statement corresponds well with the literature data, where different yeast strains and species were screened for 2-PE production [7]. …”

“…Comparison of the obtained final titers of 2-PE with the literature data indicates that Y. lipolytica shows the potential to efficiently produce this metabolite. For example, A. niger produced 1.4 g/l 2-PE from 6 g/l l -Phe in 9 days [11], P. fermentans L-5 produced 0.5 g/l 2-PE from 1 g/l l -Phe in 16 h [9], strains of K. marxianus produced up to 0.9 g/l of 2-PE [7] in a non-optimized process, K. marxianus CBS600 produced 5.6 g/l of 2-PE after medium optimization [6]. In the scope of the above, the process of 2-PE production with Y. lipolytica appears promising, however it requires further research and optimization.…”

Elevated production of the aromatic fragrance molecule, 2‐phenylethanol, using Metschnikowia pulcherrima through both de novo and ex novo conversion in batch and continuous modes

“…The 2PE produced in both cultures was approximately similar to the theoretical 2PE percentage conversion from L‐phenylalanine, given as approximately 74% by weight 9. This suggests that most of the L‐phenylalanine added was converted to 2PE, as well as further glucose being funnelled into the de novo synthesis.…”

“…The majority of studies demonstrate the productivity in the ex novo bioconversion of L‐phenylalanine. In particular, strains of K. marxianus are highly efficient producers in comparison with other species, with some reported to produce up to 0.89 g L −1 h ‐1 in 41 h from molasses when 7 g L −1 L‐phenylananine was added 9. The yield was increased 3.4 times when in situ product removal was applied, thus avoiding growth inhibition due to 2PE accumulation in the media.…”

“…These amino acids can then be fed into the Ehrlich pathway 6, 7. Several yeasts, mainly in the genera Kluyveromyces, Zygosaccharomyces, Saccharomycess, Hansenula, Pichia, Candida and Clavispora are reported to be able to produce 2PE 8, 9, 10, 11. However, 2PE production from these yeasts is fairly low, usually in the 10–100 mg L −1 range, via de novo synthesis (synthesis without additional L‐phenylalanine as a precursor).…”