460 POISONS I THEIR EFFECTS AND DETECTION. [§ 579 . 
with dilute acid it breaks up into sapogenin and sugar, and therefore 
the liquid after neutralisation reduces “ Fehling.” 
Sapogenin may be separated by evaporating the neutralised liquid to 
dryness, treating the dry residue with ether, which dissolves out the 
sapogenin, and finally recovering the substance from the ethereal solution, 
and crystallising it from hot alcohol. Crystals are readily obtained 
if the alcoholic solution is allowed to evaporate spontaneously. A 
solution of saponin exposed to the air gets turbid, and develops carbon 
dioxide ; not infrequently the solution becomes mouldy. 
W. von Schulz 1 has shown that saporubin, the active principle of 
Saponaria rubra, when treated with dilute sulphuric acid, gives glucose 
and various sapogenins according to the temperature, and having the 
formulae O-^H^gOg, f^i 8 ^' 27^65 ^i 8 ’^ 24 ^ 4 j C 14 H 22 O 2 5 this last melting at 
248°-250°. The sugar formed has [a] D = +23-67° and is not fermentable 
by yeast; the osazone melts at 165°-170°. 
§ 579. Effects.—Pelikan 2 has studied the effects of various saponins on 
frogs. One or two drops of a saturated watery solution of saponin applied 
subcutaneously to the leg, caused, in from five to six minutes, great weak¬ 
ness, accompanied by a loss of sensibility ; but strong mechanical, chemi¬ 
cal, or electrical stimuli applied to the foot excited reflex action, for the 
ischiatic nerve still retained its functions. Nevertheless, from the com¬ 
mencement, the excitability of the poisoned muscles was much weakened, 
and just before death quite disappeared. Section of the ischiatic nerve 
delayed the phenomena. Curarine did not seem to have any effect on 
the poisonous action. A concentrated solution applied to the heart of a 
frog soon arrests its beats, but weaker doses first excite, and then retard . 3 
The senior author has studied the general action of saponin on kittens, 
insects, and infusoria. Small doses, such as from 13 to 32 mgrms. (T to 
J grain), were injected beneath the loose skin of the back of the neck of 
a kitten, when there were immediate symptoms of local pain. In from 
five to ten minutes the respiration notably quickened, and the animal 
fell into a lethargic state, with signs of general muscular weakness ; just 
before death the breathing became very rapid, and there were all the signs 
of asphyxia. The pathological appearances after death were fulness in 
the right side of the heart, and intense congestion of the intestinal canal, 
the stomach generally being perfectly normal in appearance, and the 
kidneys and other organs healthy. The least fatal dose for a kitten 
seems to be 13 mgrms., or -04 grm. to a kilogramme . 4 
1 Chem. Centr., 1897, p. 302. 2 Berl. lclin. Wochschr., xxxvi. 186. 
3 J. Hoppe, NenenwirJcuny der Heilmittel, iv. 37. 
4 The action of saponin when applied in concentrated solution to flies is that of 
an intense irritant. There is protrusion of the sucker, and progressive paralysis. 
The common infusoria live for some time in dilute solutions of saponin—this is also 
true of some of the higher forms ; for example, a Cyclops quadricornis seemed in no 
way affected by a 2 per cent, solution. 
