Leuconostoc citrovorum Folinic acid

Cltrivorum factor (CF), folinic acid, and leuco-vorin are all N-[4[[(2-amino-5-formyl-1,4,5,6,7,8-hexahydro-4-oxo-6-pteridinyl)methyl]-amino]benzoyl]glutamic acid, I, the Leuconostoc citrovorum 8081 growth factor first reported by Sauberlich and Baumann.1 Leucovorin refers to the chemically synthesized material that contains both dL and 1L diastereomers "citrovorum factor" and "folinic acid" generally apply to the biologically synthesized 1L isomer. 

Cysteine hydrochloride, nicotinic acid, pantothenic acid plus glycine, pteroylglutamic acid plus p-aminobenzoic acid, and methionine were added in final concentrations of 50, 5, 0.5, and 0.06 iig, per milliliter with and without vitamin Bu, 5 Hfig. per milliliter. Nicotinic acid, 50 Mg. per milliliter, was completely inhibitory, while 6 Mg. per milliliter was not. Pteroylglutamic acid, p-aminobenzoic acid, pyridoxine hydrochloride, glycine, pantothenic acid, and uracil in concentrations of 0.5 Mg. per milliliter without vitamin Bis, and 50, 5, 0.5, and 0.05 Mg. per milliliter with vitamin Bis, 6 nng. per milliliter, were also tested. Ethyl alcohol (12.5%, 2.5%, 0.25%, 0.026%, and 0.0025%) and ammonium hydroxide (5%, 0.5%, 0.05%, and 0.005%) with and without vitamin Bis, 5 MMg- per milliliter, were tested because of their use in dissolving some of the substances listed above. Ethyl alcohol, 12.5% but not 2.6%, and 5% ammonium hydroxide, but not 0.5%, were inhibitory. Leuconostoc citrovorum factor (folinic acid), 75 Mg. per milliliter, did not replace vitamin Bis. 

Conjugated forms of folinic acid CF conjugate Liver Yeast Yeast Spinach Not definitely known probably corresponds to 6-formyl-tetrahydropteroyl di- and triglutamic acid Growth factor for Leuconostoc citrovorum Inactive with respect to Leuconostoc citrovorum 1950 (632)... 

The citrovorum factor (folinic acid) is assayed using Leuconostoc citrovorum 8081 ATCC (504). Folinic acid conjugate is determined by the same method as the free acid, except for a preliminary treatment with conjugase (274). 

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