Abstract
Dried Purple laver, Porphyra tenera, is the favorite seaweed among Japanese. This seaweed contains a small per cent of lipids, and it is known that the component fatty acids of lipids consist mainly of highly unsaturated fatty acids. However, a rancid odor is not detectable during storage.
In order to determine the antioxygenic activities of purple laver, the lipids were fractionated and the activity of each fraction was tested. The whole lipids were extracted with chloroform-methanol mixture, and the lipids thus obtained were fractionated by silicic acid column chromatography with increasing concentration of ethyl ether in n-hexane (Fig. 1). Phospholipids were separated in the same way but by the use of methanol-chloroform mixture (Fig. 2). Approximately 35 per cent of the whole lipids were phospholipids and 25 per cent were triglycerides. Upon analyzing fatty acids of each fraction by gas-liquid chromatography, it was clear that 40-55 per cent of fatty acids comprised C22 : 5 acid. In particular, phospholipi s were characteristically rich in C22 : 5 acid (55%).
According to the results of the comparison of the antioxygenic activity of each fraction, the whole lipids and the phospholipids fraction showed similar effect with BHT used as control; moreover, both of them showed the effect as synergist (Fig. 3 and 4).
