PURIFICATION OF THE ANTIHEMORRHAGIC VITAMIN BY DISTILLATION

Abstract

A method for the concentration of the antihemorrhagic vitamin from alfalfa has been described in a preceding paper.lIt is the purpose of the present report to describe results obtained in an attempt to purify this vitamin further by distillation under a high vacuum.An apparatus was set up with a Cenco Hyvac mechanical oil pump and two glass oil vapor diffusion pumps in series.These were connected to a mercury vacuum gage and to a distillation vessel.The distillation vessel consisted of a glass cylinder, inside of which was placed an upright water-cooled glass condenser with a flat, circular lower end.This end of the condenser was held at a distance of 3.5 cm.from the lower end of the glass cylinder, which was also closed and flattened.Heat was applied to the distillation vessel by means of an oil bath and electrical heating coils.A concentrate prepared as described in the preceding paper' was dissolved in hexane and the solution placed in the distillation vessel.The solvent was then driven off by applying gentle heat and the pressure reduced by connection with an aspirator for several hours.The condenser was then inserted and the vessel evacuated by the mechanical and diffusion pumps to a pressure of approximately 10e6 mm. of mercury.Warming the distillation vessel to a temperature of 40" caused a distillation of a colorless oily fraction, all of which passed over to the foot of the condenser at a temperature below 70".This fraction was about 50 per cent of the crude vitamin concentrate.Assays with chicks* revealed that the coIorIess oily fraction contained no detectable amount of the antihemorrhagic vitamin, while