LABILE CITROVORUM FACTOR IN URINE

Labile citrovorum factor in urine.

The isolation of N10 formylfolic acid' from natural materials has been reported by several groups of workers (Rauen et al., 1952; Rauen and Jaenicke, 1953; Greenberg, 1954a; Silverman et al., 1954). It was concluded that the compound had been derived either from the degradation of a labile intermediate involved in the conversion of a bound (microbiologically inactive) form of folic acid in live...

The nature of labile citrovorum factor in human urine.

The occurrence in human urine of a factor labile to heat and alkali which replaces citrovorum factor (CF; 5-formyl-5,6,7 ,%tetrahydrofolic acid; 5-formyl-THFA) in supporting the growth of Leuconostoc citrovorum, strain 8081 (Pediococcus sp. (1)) has been observed (2). This growth activity is lost upon autoclaving (pH 6.0 to 7.0) or during storage of urine at room temperature at pH 4.5 or above....

Determination of folic acid and citrovorum factor in animal tissue.

Much work has been done on the liberation of bound folic acid from tissues of animal origin. In general, there exist in animal tissues two distinct conjugase systems. One has an optimum pH around 7 and is present in such tissues as rat liver (l-3) and chicken pancreas (2, 4, 5). The other has a pH optimum around 4.5 and is present in a wider range of tissue. Hog kidney is a notable example (4, ...

Synthesis of citrovorum factor by Leuconostoc citrovorum; potentiation by ascorbic acid.

Synthesis of citrovorum factor in rats given chloretone.