鱈幽門垂の脂質

Abstract

Lipides of pyloric caeca contain large amounts of vitamin A. So, various works on vitainin A of the lipides have been reported by many investgators. But we have very little knowleges about the nature of lipides of pyloric caeca. From such a point of view, authors studied lipides of pyloric caeca of cod (Gadus macrocephalus). Our experiments are as follows: 1. Preparation of lipides. Chopped pyloric caeca are heated under reduced pressure to remove greater part of water of this tissue. Then alcohol and excess benzene are added and distilled. By such treatment, water remained is distilled out as triazotropic mixture (alcohol-benzene-water). Lipides are obtained after removing excess benzene. 2. Properties and composition of lipides. Analytical data of the lipides are shown in Table I. Composition of the lipides is shown in Table II. Lipides of cod pyloric caeca are characterized by the following points. a) Large amounts of free fatty acids and small amounts of neutral fats are remarkable. It is due to the factt that the neutral fats of original lipides had already undergone considerable autolysis. b) Large amounts of unsaponifiable mnatters, vitamin A, sterol and phosphatide are also remarkable. It is probably. characteristic of lipides of pyloric caeca, comparing its data with that of liver oil (unsap., ca. 1%; vitamin A, ca. 10, 000 U. S. P. units; phosphatide, trace). 3. Properties and composition of fatty acids. Analytical ?? data of fatty acids of the lipides are shown in Table III. Further, studies of fatty acids composition are performed. Results obtained are shown in Table IV, V anal VI. These data indicate that the fatty acids composition of the lipides is analogous to that of cod liver oil. 4. Unsaponifiable matter. The diagram of Table VII. illustrates the scope of the work. Properties of each fraction, are also shown in this diagram. From the data of each fraction, it is supposed that unsaponiilable matter of the lipides are composed of cholesterol (ca. 40%), vitamin A (ca. 30%), substance containing a conjugated double bond like vitamin D (ca. 10%), higher alcohols and hydrocarbon (ca. 20%). Authors obtained an unsaturated alcohol as anthraquinone β-carboxylate (m. p. 133-134°C). Free alcohol recovered from this ester melts at ca. 24°C and its iodine value is 143. The crystal of this ester is shown in Fig. 1. Futher investigation of this alcohol was not pursued.