Heptanone

Biosynthesis of 2-heptanone from octanoic acid by P. roquefortii, adapted from 143 The need to produce methyl ketones that qualify for the natural label has prompted intensive studies, and several processes involving fatty acids breakdown have been proposed 140, 277-287 , The formation of methyl ketones from fatty acids is described by the following stoichiometric equation R CH2 CH2 COOH + 02 -> R-CO-CH3 + C02 + HzO. This is an aerobic process. The biogenesis of methyl ketones is well...

Opportunities in Microbial Biotransformation of Monoterpenes

Mariet J. van der Werf1, Jan A.M. de Bont1 and David J. Leak2 1 Division of Industrial Microbiology, Department of Food Science, Wageningen Agricultural University, P.O. Box 8129, 6700 EY Wageningen, The Netherlands 2 Department of Biochemistry, Imperial College, London, SW7 2AZ, Great Britain 2 Problems Encountered in Monoterpene Biotransformation Studies 150 2.1 Chemical Instability of Monoterpenes 2.2 Low Solubility of Monoterpenes 2.3 Volatility of 2.4 Toxicity of Monoterpenes 2.5 Absence...

Definitions of Natural Flavours

A special issue that must be addressed as very relevant to bioflavours is the question of definitions of 'natural'. In the USA the Code of Federal Regulations (1990) defines a 'natural' flavour as the essential oil, oleoresin, essence or extractive, protein hydrolysate, distillate of any product of roasting, heating of enzymolysis, which contains the flavouring constituents derived from a spice, fruit juice, vegetable or vegetable juice, edible yeast, herb, bud, bark, root, leaf or similar...

Info

Proposed biosynthesis of iridoid monoterpenes in catmints found exclusively in the essential oils of catmints (Nepeta spp.) 146,147 , and aS, IS, 7aR)-nepetalactone (87) from Nepeta cataria is well known as a feline attractant 148,149 , Biosynthesis of the steroisomeric (4aR, IS, 7aS)-nepetalac-tone (88) in N. racemosa has recently received attention because it possesses the same configuration as the nepetalactol isomer (89) employed as a sex pheromone by the damson hop aphid (Phorodon...

Note Added in Proof

This addition gives details of publications that have only recently come to my attention, also to illustrate further the rapid rate of progress being made in the field of bioflavours by a growing range of expert research groups, and finally to include some papers that I just plain forgot to include. The identification of microbial strains that produce flavour molecules and the elucidation of the enzymatic mechanisms whereby plants produce flavour molecules are both proceeding apace. Christen et...

Gamma Decalactone Production

Gamma Decalactone

The synthesis of y-decalactone using intact microorganisms is a particularly good example of the use of biotransformations in the production of flavours because it required the development of truly innovative technology and has made a big commercial impact. The need for a natural source y-decalactone can be illustrated by a chemical analysis of strawberries. At least 350 molecules are thought to contribute to the taste of strawberry, including y-decalactone and over 100 esters. Fig. 10. Flow...