Newly hatched Artemia nauplii were fed four types of liposomes for 48
h. Labeled liposomes were prepared with dipalmitoyl-[2-palmitoyl-1-C-1
4] phosphatidylcholine (C-14-PC) or [1-C-14]glycine (C-14-glycine). No
n-labeled liposomes contained dietary protein, glucose, vitamins and m
inerals or physiological saline. Unfed nauplii served as the control.
After 24 and 48 h of feeding, total lipids were extracted with chlorof
orm and methanol. Solvent insoluble residues were hydrolysed with 1 N
NaOH. Methanol and chloroform fractions and NaOH hydrolysates were mea
sured for radioactivity. Approximately 15% of C-14-glycine and C-14-PC
was detected in the nauplii after 24 h. Nearly 80% of the total incor
porated C-14-glycine was recovered in the NaOH hydrolysate of the naup
lii, while 85% of the total incorporated C-14-PC radioactivity was fou
nd in the chloroform fraction. The methanol fraction, on the other han
d, contained 17% of the total incorporated C-14-glycine after 24 h. Th
e total lipid content of the nauplii fed non-labeled liposomes contain
ing dietary compounds or physiological saline was significantly higher
than that of the unfed nauplii at 24 h. There were no remarkable diff
erences in the fatty acid compositions of the nauplii among treatments
due to the similarities in the fatty acid compositions of liposomes a
nd nauplii. Arachidonic (20:4n-6) and eicosapentaenoic (20:5n-3) acid
content of the nauplii fed non-labeled liposomes containing dietary ma
terial were higher than the unfed nauplii after 48 h. The results of t
his study suggest that liposomes may be used to enrich Artemia nauplii
with phospholipids and free amino acids.