The Third Vitamin D


A SHORT time ago1 we reported that vitamin D found in ether extract of meadow hay had the same properties as described by Kon and Booth2 for vitamin D in butter, in that only one fifth of this vitamin after saponification is again found in the unsaponifiable fraction. We have since examined butter and have been able to confirm Kon and Booth's results as regards its vitamin D content. We considered it of interest to investigate whether the missing four fifths of the anti-rachitic vitamin might possibly be found in the saponifiable fraction of the ether extract of butter or hay. For this purpose, a small excess of acetic acid was added and the free fatty acids taken up with ether and isolated. It was then found that the missing four fifths of the original vitamin D were among the free fatty acids. Thus with alkali it gives a water-soluble substance; deprived of alkali, it is again soluble in ether.

Access optionsAccess options

Rent or Buy article

Get time limited or full article access on ReadCube.


All prices are NET prices.


  1. 1

    NATURE, 133, 255; Feb. 17, 1934. In this letter an error appeared. At the end of the second paragraph, for 0.25 units read 10 units.

  2. 2

    Kon, S. K., and Booth, R. G., Biochem. J., 27, 1302; 1933.

  3. 3

    Shipley, Kinney, McCollum, J. Biol. Chem., 59, 177; 1927.

  4. 4

    Zucker, Amer. J. Publ. Health, 23, 10; 1933.

  5. 5

    Poulsson, E., and Løvenskiold, H., Bioch. J., 22, No. 1; 1928.

Download references

Author information

Rights and permissions

Reprints and Permissions

About this article

Further reading


By submitting a comment you agree to abide by our Terms and Community Guidelines. If you find something abusive or that does not comply with our terms or guidelines please flag it as inappropriate.