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They yeast strains were screened to check their ability to produce the rose-like odor of phenylethanol from L-phenylalanine. One of these strains, S-8, was selected as a high phenylethanol producer and was studied in more detail. By morphological, physiological, and biochemical studies, strain S-8 was tentatively identified as Candida sp. and was named as Candida sp. S-8. Among the various carbon sources tested, glucose was the most suitable carbon source for producing phenylethanol from Candida sp. S-8. Increasing the concentrations of glucose (up to 50g/L) and L-phenylalanine (up to 4g/L) in a culture media resulted in increased production of phenylethanol. Cell growth and phenylethanol production in a semi-optimized medium containing 50g/L of glucose, 4g/L of L-phenylalanine, 4g/L of KH₂PO₄, 0.4g/L of MgSO₄?7H₂O, and 1g/L of yeast extract were 5.91g/L and 2.01g/L, respectively, after 48 hr of fermentation. The molar yield of phenylethanol was 0.95 on the basis of consumed L-phenylalanine.
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