Germacrone biotransformation

More recently, Asakawa et al. [154] described the biotransformation of germacrone by Aspergillus niger. A very unstable allylic alcohol (211) was obtained from the metabolite of germacrone along with (213), Fig. (42). 

Fig. (42). Biotransformation of germacrone by Cunninghamella blakesleeana (after [153]) and by Aspergillus niger (after [154])...

The microbial transformation of humulene, a substrate showing a structure similar to that of germacrone, was studied by Abraham and Stumpf using a screen of about 300 strains1175 . This led the authors to select the fungi Diplodia gossypina and Chaetonium cochlioides for preparative scale experiments. It was thus observed that the main reaction path starts with the epoxidation of the 1,2-double bond, as shown by direct biotransformation of this monoepoxide obtained by chemical synthesis. This is then further oxidized to yield a multitude of products including diepoxides and hydroxy-epoxides (Fig. 16.1-28). 

FIGURE 20.41 Biotransformation of germacrone (118) by Curcuma zedoaria and Curcuma aromatica cells. 

Sakamoto, S., N. Tsuchiya, M. Kuroyanagi, and A. Ueno. 1994. Biotransformation of germacrone by suspen sion cultured cells. 35 1215-1219. 

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