HEMOLYSIS BY SAPONINS 221 



larly actively licuiolytic, while riein, abiin, and robin are more marked 

 by their agglutinating action, hemolysis being produced only by 

 relatively large doses. Their effects vary greatly, however, according 

 to the species of animals whose blood is used. They resemljle the 

 bacterial toxins, in that immunity can be secured against them, and 

 the immune serum will prevent their hemolytic action. Heating 

 the toxalbumins to 65° or 70° does not destroy the hemolytic or 

 agglutinating action except with phallin, but 100° does. The action 

 of these substances is not like that of the enzymes, in that it is 

 quantitative, a given amount acting on a given amount of cor- 

 puscles to which it is bound. Madsen and Walbum" observed that 

 red corpuscles had the power of dissociating neutral mixtures of 

 ricin and antiricin, the ricin entering the corpuscles from which it 

 could be recovered. ^'^ Ford and Abel believe the hemolytic agent of 

 amanita to be a glucoside. (The general nature and other properties 

 of these substances are considered under the heading of " Phytotoxins," 

 in Chap, vi.) 



Saponin Group. — Another quite distinct group of vegetable 

 hemolyzing agents consists of the "saponin substances. "^^ These 

 are a closely related group of glucosides, found in at least 46 differ- 

 ent families of plants, and they are strong protoplasmic as well as 

 hemolytic poisons. They differ altogether from the true toxins, be- 

 ing heat resistant, having no resemblance to proteins, and not giving 

 rise to antibodies on immunization of animals.^ The degree of their 

 toxicity is not directly proportional to their hemolytic activity; they 

 seem to injure chiefly the nerve-cells. Apparently hemolysis is 

 brought about by action upon the lipoids of the red corpuscles, for 

 addition of cholesterol to saponin prevents its hemolytic effect;^ leci- 

 thin does not have the same property.^ Both cholesterol and leci- 

 thin combine with saponin, the cholesterol compound being quite 

 inert, whereas the lecithin compound is both hemolytic and toxic. 

 The compound formed between a typical saponin, digitonin, and 

 cholesterol, is so insoluble that it has been found useful in the quan- 

 titative analysis of cholesterol.'* Normal serum seems to contain 



" Cent. f. Bakt., 1904 (36), 242. 



^^ According to Pascucci (Hofmeister's Beitr., 1905 (7), 457), ricin combines 

 directly with lecithin, the compound being strongly hemolytic. 



^^ Complete literature on saponin given by Kobert, "Die Saponinsubstanzen," 

 Stuttgart, 1904; also Kunkel, "Handbuch der Toxokologie," Jena. 



1 Saponins are characterized by their ready solubility in water and the foam- 

 ing, soapy character possessed by the solution; hence their technical applications 

 as soap bark, etc. Heated with dilute acids they split off sugar; also when acted 

 on by glucoside-splitting enzymes (from spiders), according to Kobert. Saponin 

 from Quillaja (soap-bark) has the formula C19H30O10 (Stiitz). Most are colloids, 

 but some crystallize. 



2 Ransom, Deut. med. Woch., 1901 (27), 194; Madsen and Xoguchi, Cent. f. 

 Bakt., 1905 (37), 367; Pascucci, Hofmeister's Beitr., 1905 (6), 543. 



3 Noguchi, Univ. of Penn. Med. Bull., 1902 (15), 327; Meyer, Hofmeister's 

 Beitr., 1908 (11), 357. 



^ Windaus, Chem. Berichto, 1909 (42), 238. 



