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Updated: Nov 24, 2025

Experimental Protocol for Biodiesel Production with Isolation of Alkenones as Coproducts from Commercial Isochrysis Algal Biomass
Published on: June 24, 2016
Biotechnological Production and Sensory Evaluation of ω1-Unsaturated Aldehydes
Andreas K Hammer1,2, Nils O Emrich1, Janina Ott1
1Justus Liebig University Giessen, Institute of Food Chemistry and Food Biotechnology, Heinrich-Buff-Ring 17, 35392 Giessen, Germany.
Abstract:
Lipid extracts of the fungus Flammulina velutipes were found to contain various scarce fatty acids including dodec-11-enoic acid and di- and tri-unsaturated C16 isomers. A biotechnological approach using a heterologously expressed carboxylic acid reductase was developed to transform the fatty acids into the respective aldehydes, yielding inter alia dodec-11-enal. Supplementation studies gave insights into the fungal biosynthesis of this rarely occurring acid and suggested a terminal desaturation of lauric acid being responsible for its formation. A systematic structure-odor relationship assessment of terminally unsaturated aldehydes (C7-C13) revealed odor thresholds in the range of 0.24-22 μg/L in aqueous solution and 0.039-29 ng/L in air. In both cases, non-8-enal was identified as the most potent compound. All aldehydes exhibited green odor qualities. Short-chained substances were additionally associated with grassy, melon-, and cucumber-like notes, while longer-chained homologs smelled soapy and coriander leaf-like with partly herbaceous nuances. Dodec-11-enal turned out to be of highly pleasant scent without off-notes.
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