Abstract
1. Among the soybean oils which we examined the oil produced by means of the hydraulic press was the highest and the oil prepared by extraction with alcohol was the lowest in antirachitic value, while the oil obtained with the benzine extraction method had intermediate value.
2. The antirachitic vitamin in the crude oil was not appreciably removed or destroyed by the usual processes of refining.
3. The anitrachitic potency of the oil was significantly inereased by means of irradiation with ultra-violet light.
4. Phytosterol isolated from the unsaponifiable fraction of the oil was rendered antirachitie by irradiation, and exhibited the well-defined absorption bands of ergosterol in the ultraviolet region.
