カツオ幽門垂中の未知因子に関する研究-II

未知因子の性質

抄録

1. At variance with the known CF which readily loses the power of promoting the growth of Leuconostoc citrovorum after being kept at a pH lower than 2.0, the unknown factor is not damaged of its activity toward this microorganismus even when exposed to any pH in the range from 1.0 to 14 (Table 1).
2. The unknown factor is comparatively unstable to a strong acid. It loses said promotive power to some extent when boiled in 5% H₂SO₄ and is completely invalidated by heating with 25% H₂SO₄ (Fig. 2 and 4). On the other hand, the unknown factor remains comparatively stable against a strong alkali. Its characteristics toward Leuc. citrovorum are not damaged even when kept in contact with 10% KOH (see Fig. 3). In this connection, the response of Leuc. citrovorum to the unknown factor appeared to be more or less strongly suppressed in the presence of salt inevitably ensuing from the neutralization of the agent employed in acidification or alkalization.
3. The unknown factor can be selectively adsorbed on an ion-exchange resin, only when the resin is of strong acid form (see Table 2 and Fig. 5). It can also be desorbed from the exchanger by means of 0.5N NaOH.
4. The unknown factor itself could not be precipitated by the addition of any agent thus far tested.
5. A crude preparation of the unknown factor was positive to diazo reaction, Morlish's reaction and Folin's reaction, but negative to ninhydrin reaction (Table 4).