Formation of tiglic and n-valeric acids by bacteria-free Ascaris lumbricoides.

In an attempt to fractionate Cg acids produced by Ascaris with the aid of partition chromatography, it was noted that one fraction had distribution characteristics resembling those of n-valeric acid (2). Elution of this fraction began earlier than, but was completed simultaneously with, that of n-Valerie acid. Therefore, it appeared that this fraction may consist of at least two components. Evidence for the heterogeneity of this fraction was obtained from observations on the bromine uptake of its aqueous solutions. They indicated that approximately 60 per cent of this fraction consisted of an unsaturated acid, the remainder of a saturated acid (2). Since bromine uptake was considerably greater in the first portion of the eluate than in the last, it was evident that the unsaturated acid was eluted earlier than the saturated one. By repeated subfractionations of this material on the buffered Celite columns described earlier (2) (pH of non-mobile phase, 7.8; mobile phase, 1 per cent butanol in chloroform), eventually two distinct compounds were obtained; one of them took up 2 m.eq. of bromine per milliequivalent of acid, indicating the presence of one double bond. The second fraction took up no bromine. Identification of these sat,urated and unsaturated acids will be described below.