プランクトンの脂質に関する研究 (第4報)

Calanus plumchrusの脂質の不ケン化物

抄録

The anthers studied on the Unsaponifiable matter of the lipid of crustacean plankton, Calanus plumchrus.
Calanus plumchrus belongs to the pelagic species living in cold sea, and it is distributed in the Kurile Current area of North Hokkaido, Sea of Okhotsk and Bering Sea.
The unsaponifiable matter was liquid of reddish brown color contained ca. 50% in the lipid, and its characteristics were as follows : n²⁵_D 1.4620, I.V. 98.7, and sterol content 2.0%.
The unsaponifiable matter was resolved into several constituents on silicic acid chromatography and these were analyzed.
It contained ca. 80% of fatty alcohol, ca. 2% of pristane and ca. 2% of sterol.
The fatty alcohols consisted of saturated alcohols (hexadecanol predominantly, octadecanol and eicosanol) and lower unsaturated alcohols (hexadecenol, octadecenol, eicosenol and docosenol). Higher unsaturated alcohols were contained in a small amount or not.
Specific gravity (d¹⁵₄) of the lipid of Calanus plumchrus is 0.880.89 as previously reported, which is smallar than that of other genus of plankton and many marine fishes. The lowness of this value of the lipid depends upon the presence of 50% of unsaponifiable matter which contains 80% of fatty alcohols.
As one of the authers already discussed about the ecological functions of these lipid, the reason for the high content of fatty alcohols seems probably that their functions are related to the plankton moving vigorously and especially vertically with depth, namely may be for buoyancy in such plankton.
Sperm whale and the sharks living in deep sea have the lipids rich in fatty alcohols and hydrocarbons respectively.
It seems that the formation and presence of such non-glyceride constituents as fatty alcohols and hydrocarbons are related to the ecological or physiological functions common to the marine organisms living in deep sea.
Recently, Nevenzel et al. and Mori et al. reported on the lipid of deep-sea fishes. They found that wax esters constituted greater part of the lipids from muscle. This finding is in accordance with our informations on the lipid rich in fatty alcohols.
Hydrocarbons in the lipid of plankton have been reported by Blumer. They have found that the hydrocarbon pristane occared in unusually high concentration (1 to 3% of the body fat) in the three copepods Calanus finmarchicus, C. glacialis, and C. hyperboreus, and considered that these planktonic crustaceans appear to be the primary source of the pristane in liver oil of sharks and whales.
Authers also found 2% of pristane in the unsaponifiable matter of the lipid of Calanus plumchrus.