Uptake of alpha-Linolenic Acid and its Conversion to Long Chain Omega-3 Fatty Acids in Rats Fed Microemulsions of Linseed Oil.

The present work was designed to prepare linseed
oil (LSO) microemulsion and explore the possibility of
enhancing the uptake and utilization of a-linolenic acid
(ALA) present in LSO. The bioavailability of encapsulated
LSO as against native oil was monitored in rats by measuring
the uptake in vitro using the intestinal everted sac
model and in-vivo administration of microemulsions of
LSO to rats for a period of 30 days. Microemulsions were
prepared by using different binding materials such as gum
acacia, whey protein and lipoid. When LSO was encapsulated
with gum acacia, whey protein and lipoid, the levels of
ALA uptake into intestinal sacs was increased by 6, 17 and
28 % as compared to oil given without encapsulation. EPA
and DHA were not observed in the oil absorbed by intestinal
everted sacs when given as emulsions with gum acacia or
whey protein. When LSO was given as microemulsions
with lipoid, EPA ? DHA was observed in oil absorbed by
intestinal sacs. Similarly when LSO was given as a lipoid
emulsion by intubation to rats, the EPA and DHA in serum
lipids were found to be 41 and 34 lg/ml, respectively while
rats given LSO without encapsulation contained EPA and
DHA at 9.1 and 8.8 lg/ml, respectively. Similar changes in
omega-3 fatty acid content in liver lipids were observed
when LSO was given as a microemulsion with lipoid. This
study indicated that ALA was taken up and metabolized to
long chain omega-3 PUFA when given as microemulsion
with lipoid.