Biocatalytic Production of Odor-Active Fatty Aldehydes from Fungal Lipids

• Published in: Journal of agricultural and food chemistry 2023-05, Vol.71 (21), p.8112-8120
• Main Authors: Kanter, Jean-Philippe, Honold, Philipp Jakob, Luh, David, Heiles, Sven, Spengler, Bernhard, Fraatz, Marco Alexander, Zorn, Holger, Hammer, Andreas Klaus
• Format: Article
• Language: English
• Subjects: Aldehydes - metabolism; Biotechnology and Biological Transformations; Chromatography, Gas; Dioxygenases; Fatty Acids - metabolism; Odorants - analysis
• ISSN: 0021-8561; 1520-5118
• DOI: 10.1021/acs.jafc.3c01972

Odor-active fatty aldehydes are important compounds for the flavor and fragrance industry. By a coupled enzymatic reaction using an α-dioxygenase (α-DOX) and an aldehyde dehydrogenase (FALDH), scarcely available aldehydes from the biotransformation of margaroleic acid [17:1­(9Z)] were characterized and have shown highly interesting odor profiles, including citrus-like, soapy, herbaceous, and savory notes. In particular, (Z)-8-hexadecenal and (Z)-7-pentadecenal exhibited notable meaty odor characteristics. Submerged cultivation of Mortierella hyalina revealed the accumulation of the above-mentioned, naturally uncommon fatty acid 17:1­(9Z). Its production was significantly increased by the modulation of culture conditions, whereas the highest accumulation was observed after 4 days at 24 °C and l-isoleucine supplementation. The lipase-, α-DOX-, and FALDH-mediated biotransformation of M. hyalina lipid extract resulted in a complex aldehyde mixture with a high aldehyde yield of ∼50%. The odor qualities of the formed aldehydes were assessed by means of gas chromatography–olfactometry, and several of the obtained fatty aldehydes have been sensorially described for the first time. To assess the aldehyde mixture’s potential as a flavor ingredient, a sensory evaluation was conducted. The obtained product exhibited intense citrus-like, green, and soapy odor impressions.