Norite eluate factor

Nutritional studies with Lactobacillus casei and Streptococcus faecalis R resulted in the discovery of new growth factors given the names norite eluate factor and folic acid, respectively. Assay methods using these two organisms were employed in the isolation of folic acid and related compounds from natural extracts. However, a number of previously reported biological responses to natural extracts may now be attributed to the folic acid group. 

Synonyms Vitamin Be, norit eluate factor, liver L. casei factor, fola-cin, folic acid. ... 

Snell and Peterson (534) noted that one could extract the norit eluate factor from an aqueous solution by butanol at pH 4.0, whereas at pH 7.5 it was insoluble in butanol. Hutchings, Bohonos, and Peterson (299) stated that the norit eluate factor precipitated quite specifically as the zinc salt. Pfiffner et al. (459), succeeded in preparing crystalline vitamin B, by com-... 

Norit eluate factor Yeast Liver Later found to be identical with the L. casd factor Growth factor for L. casei 1939 (533) o... 

L. casei factor Eluate factor , Norite eluate factor ). Snell and Peterson (56) reported in 1940 that, among the substances required by Lactobacillus casei e, was one found in yeast, liver and other natural materials, which could be adsorbed on norite and eluted therefrom with ammoni-acal alcohol. They referred to this substance as the eluate factor , and described methods for its concentration. Stokstad (57) and Hutchings, Bo-honos, and Peterson (58) carried the concentration somewhat further. Hutchings, et al. also described chemical properties of the factor and showed that a concentrate stimulated the growth of several strains of lactic acid... 

The same technique applies to the preparation of vitamin B from horse liver, which is even richer than hog liver in this vitamin (459). The preparation of vitamin B, from yeast is carried out by the same technique, after a treatment of the yeast extract with conjugase. The crystallized product obtained from yeast is identical with that prepared from liver. Stokstad et al. (557) isolated the liver L. casei factor from the precipitate obtained by treating the aqueous liver extract with 85% ethanol. The active substance is separated by successive adsorption on norit A and Superfiltrol, the last eluate being precipitated by baryta and ethanol. The L. casei factor is esterified, and the esterified product is extracted by butanol. After removal of butanol, the substance is dissolved in methanol and chromatographed on a column of Superfiltrol. It is then eluted with 70 % aqueous acetone. The active esterified product thus eluted is pure, and on hydrolysis yields the free acid which crystallizes. The latter is identical to the vitamin Bo of Pfiffner et al. (459). 

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