Conclusions
Isoascorbyl palmitate was successfully synthesized by
using lipase-catalysed esterification of isoascorbic acid
and palmitic acid under the mild reaction conditions. It
structure was characterized by LC-MS, FT-IR, 1H, and
13C NMR. The effect of various parameters on synthesis
of D-isoascorbyl palmitate, such as enzyme source, type
of organic, enzyme load, reaction time, temperature, molecular
sieves content and D-isoascorbic-to-palmitic acid
molar ratio were discussed using “one–factor-at-a-time”
experiments and Response surface methodology. The
optimized condition was obtained as follow: enzyme
load of 20% (w/w), reaction temperature of 53°C and
D-isoascorbic-to-palmitic acid molar ratio of 1:4. Under
these optimal conditions, 95.32% of conversion rate was
obtained which was in agreement with the predicted
value (96.98%). The results are of a reference for developing
industrial processes for the preparation of isoascorbic
acid ester, which might be used in food additives, cosmetic
formulations and for the synthesis of other isoascorbic
acid derivatives.