Briefly, 70 mg lipids
were stirred with 0.5 mL of 5% KOH methanol solution at 65 C
for 50 min, followed by the addition of 0.2 ml of BF3 diethyl etherate
and 0.5 ml of methanol, refluxed for 10 min, cooled, diluted
with distilled water and extracted with hexanes.