471 



dried at 37°. Afterwards tlie red corpuscles were extracted for one liour by petrol- 

 ether at room temperature; in this way neutral fat and most of cholesterin are 

 extracted without any loss of haeraolytics. The following quantitative extraction 

 of haemolytics was made in a specially constructed small apparatus for 'boiling- 

 point extraction", with always freshly destilled fluid, adaptable for small quantities. 

 As extraction-liquid acetone was chosen in analogy to the use of this liquid in 

 phosphatid chemistry. In order to extract the haemolytics completely with acetone 

 a preceeding treatment with alcohol-vapour fur half an hour was necessary ; the 

 than following acetone extraction dissolves all haemolytics in two hours. 



To complete purification the acetone-extract was concentrated to a small volume and 

 allowed to stand for one night in ice. In this way most of thedissolved substances are 

 precipitated but no haemolytics are found in the precipitate. The remaining strongly 

 active fraction has the following properties: it can be dissolved in all typical 

 lipoiddissolving liquids, if the reaction is slightly acid, but in an alkaline medium 

 the haemolytics are insoluble is petrol ether. The examined substances are not 

 precipitated by cadmium, but they are precipitated quantitatively in aquous solution 

 by barium and in acetone solution completely by an ammoniacal solution of acetate 

 of lead, in the presence of not less than 30 "/g of water 



So we see, that the investigated haemolj'tios show the typical 

 reactions of the liif^iier fatty acids. The said precipetate contained no 

 phosphorus, so that phosphatides can be excluded i\et\n'ite\y, mn/ ike 

 haetnolt/t/cs, which atn be extracted from noniial blood must be 

 identified irith higher fatty acids res/), their .ioaps. 



Tiie soiiihilty of the PI) and Ba sails indicaled, that a niixtnre of 

 fatty acids mnst be pi'esent, containing no or one and also more 

 than one donble linkage. Fiirthei' e.xperitnents must determine the 

 constitution and procentnul concentration of these substances. 



Separation of the fraction of liie fatty acids and of phosphatids 

 can only be obtained by careful quantitative methods of working; 

 it is probable, that complete separation was not got by former 

 investigators. 



In addition to these results we have examined once more the 

 liaemolytic action of pure lecithin. If was found that a praeparaiion 

 ot lecithin purified by the newest methods showed no haemolytic 

 properties; the haemolytic action of common trade lecithin must be 

 ascribed to impurities, and this also is the case if this substance is 

 somewhat purified by the usual acetone-precipitation. 



With the knowledge, that the haemolytics of lipoid blood extract 

 are higher fatty acids it is possible to isolate them in a simpler 

 way. This may be done by the following method: the dried blood, 

 sucked in filterpaper (5 cc. of blood) is treated with absolute alcohol 

 for one hour in the boiling-point extraction apparatus. The extract 



