Regioselective biooxidation of (+)-valencene by recombinant E. coli expressing CYP109B1 from Bacillus subtilis in a two-liquid-phase system

Table 2 Product distribution and conversion of (+)-valencene (1) by CYP109B1 in biphasic systems^a

Biphasic system	cis-nootkatol (2)^b	trans-nootkatol (3)^b	(+)-nootkatone (4)^b	RT 12.1 min^b	RT 12.3 min^b	RT 13.3 min^b	Conversion [%]^c	Volumetric productivity [nM min^-1]
aqueous	6.2	55.1	4.0	2.3	27.2	5.2	24.7 ± 3.8	990 ± 158
10% dodecane	7.4	82.8	2.6	---	6.1	1.1	19.5 ± 2.9	859 ± 121
20% dodecane	7.6	85.6	2.7	---	3.9	0.2	17.2 ± 1.8	719 ± 75
10% n-octane	7.7	80.2	3.2	0.4	7.3	1.2	16.4 ± 2.7	770 ± 116
20% n-octane	8.5	81.3	3.8	---	5.3	1.1	14.4 ± 2.4	502 ± 101
10% isooctane	10.1	74.9	4.1	0.1	8.5	2.3	9.6 ± 1.6	399 ± 68
20% isooctane	11.3	78.3	4.5	---	4.6	1.3	7.8 ± 1.8	313 ± 84
10% hexadecane	10.8	80.4	2.8	---	5.3	0.7	15.1 ± 3.5	631 ± 150
20% hexadecane	12.6	81.7	3.0	---	2.7	---	9.3 ± 1.2	387 ± 53

^aConversion of 2 mM (+)-valencene (1) was carried out with recombinant E. coli expressing PdR, Pdx and CYP109B1 in 2 ml CV2 buffer with 2% DMSO for 8 h at 30°C and extracted with ethyl acetate. All values are shown as mean (± standard deviation), n ≥ 3.
^bValues are given in % of the total product.
^cPercental amount of (+)-valencene (1) that was converted to products.
RT: Retention time during GC (for unidentified products).
---: Compound was not observed in the reaction. The detection limit was 4 μM.

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