226 CHE^[IsTl,•y or rni: immimtv reactioxs 



which it is bound. ^Madsen and Walbuni '^- observed that red corpiis- 

 t'les had the power of dissociatino- neutral mixtures of ricin and anti- 

 riein, the ricin entering the corpuscles from which it could be recov- 

 ered.®^ Ford and Abel believe the hemolj^tic agent of amanita to be 

 a glucoside. (The general nature and other properties of these sub- 

 stances 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 lea.st 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 M'ith 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 

 an antihemolysin for saponin, and therefore hemoglobinuria is not 

 produced by all saponins on intravenous injection. Careful immu- 

 nization leads to a slight increase in this antihemolytic action of the 

 serum, possibly due to an increased formation of cholesterol (Ro- 

 bert). The resistance of corpuscles to saponin hemolysis varies in 

 disease, being especially low in jaundice (M'Neil).*"' 



A study of the toxicity of the members of this group by Kobert '° 

 shows that in general they have similar properties, but that minor 



c2Cent. f. Bakt., in04 (36). 242. 



IS According to Pascueoi (Hofmeister's Bcitr.. 1905 (7). 4.5"). riein combines 

 directly with lecitliin, the compound beinjr strongly liemolytic. 



f* Completo litoraturc on saponin pivon by Kobert. "Die Raponinsnbstanzen." 

 Stuttgart, 1004: also Kuiikel. "Handi)iicli der 'I'oxokolotrie," .Tena. 



6''' Saponins are cliaracterized by tlieir ready solubility in water and the 

 foamino:, soapy character possessed by tlie solution; hence their teclinical appli- 

 cations as soap bark, etc. Heated with dilute acids they split ofT sugar; also 

 when acted on by frlucoside-spliUin"r enzymes (from spiders), accordinsr to 

 Kobert. Saponin from QiiiUnja (soajj-bark) has the formula f",„lT;,„0,o (Stiitz). 

 Most are colloids, but some crystallize. 



66 Ransom, Dent. mcd. Woch., 1001 (27). 104: INbidsen and Xounulii. Cent. f. 

 Bakt.. 100.5 (.'^7). .367; Pascucci, Hofmeister's Beitr.. 1005 (6). .543. 



OTXopuchi, Univ. of Benn. Med. Bull., 1002 (15), .327: Meyer. Hofmeister's 

 Beitr.. 1008 (11), 357. 



«8Windaus, C'hem. Berichte. 1000 (42), 238. 



co.Tour. Path, and Bact.. 1010 (15), 56. 



70 Arch. exp. Path. u. Pharm., 1887 (23), 233. 



