AmMirch,f902.rnJ'}         Animal  Digestive  Ferments.  115 
Alcohol  in  any  percentage  used  in  pharmaceutical  and  medicinal 
preparations  is  immediately  diluted  to  a  negligible  quantity  in  the 
stomach  in  its  relation  to  the  enzyme  in  its  ordinary  exhibition  ; 
and  in  submitting  alcohol  preparations  to  the  usual  digestive 
test  the  alcohol  forms  so  small  a  percentage  of  the  digesting 
mass  as  to  exert  no  retarding  influence  upon  the  action  of  the 
enzyme. 
It  was  thought  that  because  wines  of  pepsin  were  found  by  Squibb 
to  be  feeble  or  practically  inert,  their  defect  was  necessarily  due  to 
the  presence  of  alcohol ;  but  this  is  not  the  fact. 
In  the  first  place,  there  was  no  certainty  that  the  vinous  or  elixir 
preparations  of  pepsin  had  ever  had  any  vital  pepsin  in  them,  or 
that  the  pepsin  had  not  been  injured  by  the  acid  in  the  preparation. 
The  conventional  quantity  of  pepsin  used  in  those  days  was  a 
grain  of  the  saccharated  to  one  or  two  teaspoonfuls,  so  that  a  tea- 
spoonful  of  such  preparation  could  by  assay  digest  only  twelve  to 
fifteen  grains  of  albumen.  Preparations  containing  sufficient  alcohol 
and  glycerin  to  ensure  stability  are  readily  made  directly  from  the 
stomach,  of  which  one  teaspoonful  upon  U.S. P.  assay  will  convert 
from  2,000  to  3,000  grains.  There  is  an  evident  error  in  the  attempt 
sometimes  made  to  "assay"  fluid  preparations  of  pepsin  containing 
alcohol  by  adding  the  coagulated  albumen  directly  to  the  prepara- 
tion. The  question  to  be  asked  of  an  alcoholic  preparation  of  pepsin 
is,  whether  it  exhibits  the  action  of  pepsin  when  submitted  to  the 
proper  (physiological)  conditions — just  as  we  assay  the  dry  ferment, 
and  thus  only  we  determine  its  pepsin  strength. 
It  was  early  observed  that  pepsin  was  destroyed  by  maceration 
with  sodium  carbonate  and  free  alkali  in  minute  percentages  ;  pep- 
sin has  also  been  spoken  of  as  being  "  altered  "  or  "  modified  "  by 
the  action  of  an  alkali. 
Inasmuch  as  formulas  have  been  suggested  in  which  the  neutral- 
ization of  the  acid  pepsin  infusion  is  directed,  it  is  worth  while  to 
mention  that  pepsin  is  injured  if  the  neutralization  be  carried  to  the 
very  faintest  alkalinity,  and  that  this  occurs  instantly,  and  at  ordi- 
nary temperatures  ;  the  pepsin  cannot  be  considered  "  modified  "  or 
u  altered  "  pepsin  in  any  sense  ;  it  is  simply  annihilated  ;  its  activity 
cannot  be  restored  by  acidification  or  by  any  treatment. 
In  a  word,  it  may  be  said  that  in  determining  the  pharmaceutical 
possibilities  of  a  preparation  of  the  enzymes,  the  question  is  not 
