Linalool Botrytis cinerea

The biotransformation of linalool by Botrytis cinerea has also been described [60]. After addition of linalool to botrytised must, a series of transformation products was identified (E)- (49) and (Z)-2,6-dimethyl-2,7-octadiene-l,6-diol (48), trans- (76) and cw-furanoid linalool oxide (77), trans- (78) and c/s-pyranoid linalool oxide (79) and their acetates (80, 81), 3,9-epoxy-p-menth-1 -ene (75) and 2-methyl-2-vinyltetrahydrofuran-5-one (66) (unsaturated lactone), Fig. (11). Quantitative analysis however, showed that linalool was predominantly (> 90%) metabolised to ( )-2,6-dimethyl-2,7-octadiene-l,6-diol (49) by B. cinerea. The other compounds were only found as by-products in minor concentrations. 

Fig. (11). Biotransformation products of linalool by Botrytis cinerea (after [60])...

Biotransformation of linalool was studied in grape must using three strains of Botrytis cinerea (5901/2 5901/1 5899/4). Capillary gas chromatography (HRGC) and coupled capillary gas chromatography-mass spectrometry (HRGC-MS) revealed predominant conversion (> 90 %) of linalool to (E)-2,6-dimethyl-2,7-octadiene-l,6-diol. 

Figure 4. Structures of terpenoids formed from linalool (1) by Botrytis cinerea. (19)>(20) (E)- and (Z)-2,6-dimethyl-2,7-octadie-ne-l,6-diol (21),(22) (Z)- and (E)-linalool oxides, furanoid (23),(24) (Z)- and (E)-linalool oxides, pyranoid (25),(26) (Z)-and (E)-linalool oxide acetates, pyranoid (27) 3,9-epoxy-p-menth-1-ene (28) 2-vinyl-2-methyl-tetrahydrofuran-5-one.

Figure 5. Quantitative distribution of terpenoids (19)-(28) (cf. Fig.4) formed from linalool (1) by three strains of Botrytis cinerea (a = 5901/2 b = 5909/1 c = 5899/4).

FIGURE 19.19 Biotransformation products of linalool (206) by Botrytis cinerea. (Modi ed from Bock, G. etal., /. FoodScL, 51, 659, 1986.)... 

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