The Action of Ozone on the Fat-soluble Factor in Fats

IN a previous communication [Zilva, 1919] it was shown that when butter was spread in a thin layer on a plate and exposed to ultra-violet rays for six to eight hours, the fat-soluble factor in it was inactivated.It was then pointed out that as ozone was produced by the mercurv quartz lamp from the atmospheric oxygen the butter was at the same time exposed to the action of this gas, and that further investigation would be required in order to ascertain whether the inactivation was due to the action of the rays or to that of the ozone.It was therefore decided to establish the influence of ultra-violet rays on the fat-soluble factor in the absence of oxygen and the action of ozone on it in the dark, as well as to determine the iodine value of the fat under different conditions of exposure.As the results were of great interest, the inquiry into the action of ozone was extended to the antineuritic and antiscorbutic factors.The object of this note is to give a brief summary of the results obtained by studying the action of ozone on the fat- soluble factor only.The experimental data are reserved for another com- munication in which the influence of ozone on all the accessory factors will be described and discussed in detail.For technical convenience active fats which are transparent and liquid at room temperature, likewhale oil and cod liver oil, were chosen forthisinvestigation.The latter oil being very active was found to be the more suitable and most of the experiments were therefore carried out with it.On exposure for six to eight hours in shallow layers in Petri dishes to the action of the ultraviolet rays in an atmosphere containing ozone these oils were entirely in- activated.Unlike the butter, however, the cod liver oil was not bleached but assumed a slightly darker colour, which suggests that the nature at least of some of the colouring matter associated with it is different from that of butter.In order to study the effect of ultra-violet rays on the fat-soluble factor in cod liver oil in the absence of oxygen the oil was placed in a thin layer a few millimetres thick between two tubes, one of which fitted loosely into the