Microbial production of 4-hydroxybenzylidene acetone, the direct precursor of raspberry ketone.
OBJECTIVE
To investigate the enzymatic aldol reaction between acetone as a donor and 4-hydroxybenzaldehyde as a receptor to generate 4-(4-hydroxyphenyl)-but-3-ene-2-one or 4-hydroxybenzylidene acetone, the direct precursor of 4-(4-hydroxyphenyl)-butan-2-one or raspberry ketone, using different species of filamentous fungi and bacteria.


RESULTS
Different classes of micro-organisms were tested in a medium containing mainly acetone and 4-hydoxybenzaldehyde. Of the micro-organisms tested, only bacteria were able to synthesize significant amounts of 4-hydroxybenzylidene acetone, ranging from 15 to 160 mg l(-1) after 21 h of bioconversion, as a function of the bacteria tested.


CONCLUSIONS
The biological production of 4-hydroxybenzylidene acetone has been described with bacteria possessing 2-deoxyribose-5-phosphate aldolase (DERA, EC 4.1.2.4). This result suggests that DERA is involved in the catalytic aldolization of precursors for the production of 4-hydroxybenzylidene acetone.


CONCLUSIONS
Raspberry ketone or frambinone represents a total market value of between euro6 million and euro10 million. The possibility of producing its direct precursor through a simple process using bacteria is of considerable interest to the flavour market and the food industry as a whole. This paper broadens the spectrum for the use of aldolase to achieve the biological synthesis of compounds of interest.
Feron
G
G
Laboratoire de Microbiologie, UMR INRA-UB 1232, 17 rue Sully, Dijon Cedex, France. feron@dijon.inra.fr
Mauvais
G
G
Martin
F
F
Sémon
E
E
Blin-Perrin
C
C
D001409:Bacillus cereus / Q000201:enzymology / Q000254:growth & development / Q000378:metabolism*; D001412:Bacillus subtilis / Q000201:enzymology / Q000254:growth & development / Q000378:metabolism*; D002074:Butanones / Q000737:chemistry / Q000378:metabolism*; D003470:Culture Media; D004926:Escherichia coli / Q000201:enzymology / Q000254:growth & development / Q000378:metabolism*; D005634:Fructose-Bisphosphate Aldolase / Q000378:metabolism; D005658:Fungi / Q000254:growth & development / Q000378:metabolism; D007218:Industrial Microbiology / Q000379:methods*; D012267:Ribosemonophosphates / Q000378:metabolism
D002074:Butanones; D003470:Culture Media; D012267:Ribosemonophosphates; C058245:2-deoxyribose 5-phosphate; C035522:raspberry ketone; C025383:benzylideneacetone; D005634:Fructose-Bisphosphate Aldolase