Preparation of C9 aldehydes, alcohols and their esters, for use as aroma and flavoring agents, from unsaturated fatty acids, comprises modifying specific enzyme activities in e.g. plants

摘要

Preparation of C9 aldehydes (I) or C9 alcohols (II), or their esters (IIa), from polyunsaturated fatty acids (III) having double bonds at at least positions DELTA 6 and DELTA 9, particularly C18 acids and specifically psi -linolenic or stearidonic. Preparation of C9 aldehydes (I) or C9 alcohols (II), or their esters (IIa), from polyunsaturated fatty acids (III) comprises that nucleic acid encoding plant or microbial proteins with 9-lipoxygenase (A) and 13-hydroperoxide lyase (B) activities are incorporated into a prokaryotic or eukaryotic cell under control of regulatory elements, and (A) and (B) are expressed. Recombinant (A) converts (III) to 9-hydroperoxides and these are converted, by (B), to (I). Optionally (I) are reduced to (II) and these optionally converted to (IIa), particularly with acetic acid. (I), (II) and (IIa) may then be recovered from the cells. Independent claims are also included for the following: (1) preparation of (I), (II) and (IIa) by reacting (III) with (A) and (B), optionally in presence of reducing agent and acid; and (2) preparation of transgenic plants or plant cells with increased content of (I), (II) or (IIa).