Observations on some Processes of Oxidation in Blood-serum

Abstract

A faintly alkaline mixture of normal human blood-serum with a small quantity of K4Fe(CN)6 absorbs O at the rate of about 0.25 cc. per cc. of fluid per hr. when shaken with air at room temp. The ferricyanide may be replaced in this reaction by KMnO4 or by Fe (OH)3, but not by FeCl3 in faintly acid solution nor by (K2Cr2O7) in either alkaline or acid solutions. With serum from patients exhibiting lipemia the O absorption is more rapid. The oxidizable material is contained in the lipid fraction extractable from the serum by ether. Reduced oxi-dizibility of the extracted serum can be in great measure restored by the re-addition of this lipid fraction recovered by the evaporation of the ether extract in an inert atmosphere. The oxidizable lipid is precipitated completely by full saturation of the serum with (NH4)2 SO4, partially by 1/2 saturation, but scarcely by 1/3 saturation. This behavior would be expected from a consideration of the simultaneous precipitation of lipids with proteins.