Thymol metabolic pathways

FIGURE 19.106 Metabolic pathways of (-)-carvone (93 ) by Aspergillus niger TBUYN-2 and Absidia glauca ATCC 22752. (Modi ed from Demirci, F. et al.. The biotransformation of thymol methyl ether by dif ferent fungi. Book of Abstracts of the XII Biotechnology Congr., p. 47, 2001.)... 

FIGURE 19.201 Metabolic pathways of menthol (137), menthone (149),p-cymene (178), thymol (179), car-vacrol methyl ether (201), and carvotanacetone (47) by microorganisms and rabbit. 

Metabolic pathways of menthol (137), menthone (149), thymol (179), and carvacrol methyl ether (202) are summarized in Figure 19.201. Menthol (137) is generally hydroxylated to give 1-hydroxy-(138), 2-hydroxy- (140), 4-hydroxy- (141), 6-hydroxy- (139), 7-hydroxy- (143), 8-hydroxy- (142), and 9-hydroxymenthol (144) and 1,8-dihydroxy- (146) and 7,8-dihydroxymenthol (148) (Asakawa et al., 1991 Takahashi et al., 1994 Van der Werf et al., 1997). Racemic menthyl acetate and menthyl chloroacetate are hydrolyzed asymmetrically by an esterase of microorganisms (Brit Patent, 1970 Moroe et al., 1971 Watanabe and Inagaki, 1977a,b). Menthone (149) is reductively metabolized to 137 and oxidatively metabolized to 3,7-dimethyl-6-hydroxyoctanoic acid (152), 3,7-dimethyl-... 

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