天然ビタミン油よりビタミンA濃縮物を経済的に製造する方法の研究―IX

メタノールを使用してA濃縮物を精製する方法

抄録

In succession to the previous experiments on this subject, technological improvement has been saught to concentrate vitamin A to a higher level and free from odor. In the present work a method for treating vitamin A concentrate with aqueous methanol under specific conditions has been successful in eliminating fishy smell as well as hydrocarbon from the previous product. The color of the refined substance was found improved to some extent.
Therefore, the method may be recommended as an approach to industrially refining vitamin A concentrate at a reduced cost. The following are the procedures of and the results from the experiments.
1) Different amounts and strengths of methanol were added to each sample of vitamin A concentrate shown in Table 1. The mixture was boiled until the solution was formed. After cooling over night, separated methnol soluble fraction was decanted and evaporated. Vitamin A was concentrated in this fraction, while vitamin D in another insoluble with methanol (Tables 2, 4 and 8).
2) Of the various procedures compared as to the refining efficiency, the most effective was found to be a twice-repeating treatment (a method) with 90% methanol 20 times as much as the vitamin A sample-the second treatment extracting the vitamin A from the residue of the first-(Table 3).
3) In determining the effect of the vitamin A material from different species of fish, a method was compared with b in which petroleum ether solution was extracted with methanol. Although the results were somewhat variable depending on the samples, the recovery of the vitamin A concentrate was greater in a method than in b, while the rate of concentration was vice versa (Table 5).
4) The methanol soluble fraction obtained by both methods was subjected to chromatographic determination with a view to separating the material into three fractions as it was chromatographed in the alumina column. Upon measuring the weights and vitamin A levels of the eluted fractions it was revealed that the components of impurities to be eliminated were variable even in the same procedure likely depending on species of fish used for the vitamin A sample (Tables 6, 7 and Fig. 1).
5) Vitamin D was separated at a high level in the methanol insoluble fraction (Table 8). It is suggested, therefore, that the method with some improvement may be adopted for separating the liveroil of some species into vitamin A and vitamin D.