Valencene Aspergillus

Biotransformation of Valencene (1) by Aspergillus niger and Aspergillus wentii.910... 

Aspergillus wentii and Epicoccum purpurascens converted valencene (1) to 11,12-epoxide (14a) and the same diol (6, 7) (Takahashi and Miyazawa, 2005) as well as nootkatone (2) and 2a hydroxyvalencene (3) (Takahashi and Miyazawa, 2006). 

FIGURE 20.7 Biotransforaiation of valencene (1) and nootkatone (2) by Aspergillus wentii, Epicoccum purpurascens, and Chaetomium globosum. 

Both ratios of 6 (115) and 7 (111 ) obtained from 3 and 4 were 1 3, respectively. From the above results, plausible metabolic pathways of valencene (1) and 2-hydroxyvalencene (3,4) by Aspergillus niger are shown in Figure 15.6 (Noma et al., 2001a). 

Although Mucor species could give nootkatone (21) from valencene (1), this fungus biotransformed the same substrate (25) to the same alcohol (30, 13.2%) obtained from the same starting compound (25) in Aspergillus sojae, a new epoxide (34, 5.1%) and a diol (35,9.9%). 

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