Resultados e Discussão

and the lowest was 0.8% (35°C), both using the BCL/ginger system.
However, the eep was > 99% and E was > 200.
Using solvents with log P ≥ 3.5, the conversion degrees for
the (R)-(+)-12 ester were 11.3-11.7%, and using solvents with log
P ≤ 1.5 they were 1.3-4.7%. The highest conversion degree was
obtained using a mixture of n-hexane:glycerol 9:1 (v/v), with a
value of 23% (r.t., 24 h), with the BCL/ginger system. In these
studies values of eep > 99% and E > 200 were obtained.
Regardless of the experimental conditions, free or immobilized
lipases in starch films showed a pronounced preference for
the enantiomer (R)-(+)-12.
The preliminary data obtained for the resolution of (R,S)-
1-phenylethanol derivatives were promising. The 1-(4nitrophenyl)ethyl
and 1-(3,4-dimethylenedioxyphenyl)ethyl acetates
were obtained in conversion degrees of 56.1 and 26.5%
(24h), respectively, in the n-hexane:glycerol 9:1 (v/v) and
BCL/ginger:PEO (7:3 m/m) systems.
In conclusion, the results reported herein show that the
starch films of taro, yam, ginger or ginger:PEO blends can be
used as supports for the immobilization of various lipases. These
systems were successfully applied in the synthesis of aroma esters
and in the resolution of enzymatic secondary alcohols, under
mild conditions.
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