Am.  Jour.  Pharm.  \ 
August,  1901.  J 
Story  of  the  Papaw. 
391 
With  the  animal  ferments,  if  the  temperature  be  raised  to  near 
140  F.,  there  is  a  diminution  in  the  digestive  action,  and  at  about 
158  F.,  pancreatin  is  destroyed  ;  pepsin  at  about  160  F.  Quite  the 
reverse  is  the  influence  upon  the  papaw  ferments.  Here  the  action, 
beginning  as  low  as  50  or  60  F.,  increases  slightly  with  the  rise  of 
temperature  until  between  155-160  F.  it  reaches  the  maxi- 
mum. The  action  is  not  entirely  destroyed  even  at  a  fe.v  moments' 
exposure  at  the  boiling  point.  A  digestive  ferment  active  at 
temperatures  ranging  from  50  F.  to  the  boiling  point  is  notable. 
Papaw  fruit  as  a  tropical  dessert. 
PRODUCTS  OF  DIGESTION  BY  THE  PAPAW  FERMENT. 
A  peculiar  phenomenon  arises  in  the  digestion  of  albumen  by  the 
papaw  enzyme.  It  is  particularly  noticeable  in  the  digestion  of  egg 
albumen  in  alkaline  solution,  but  it  is  manifest  in  the  digestion  of 
raw  flesh  albumen  in  either  acid,  neutral  or  alkaline  media.  After 
every  prolonged  digestion  there  is  found  an  undissolved  residue, 
which  many  observers  have  characterized  as  an  unchanged  albumen, 
and  which  is  usually  measured  as  undigested  residue.  But  such  is 
not  the  case.  This  residue  is  an  altered  albumen  ;  is  soluble  in  0-3 
to  0  5  per  cent,  solution  of  sodium  carbonate  or  0'2  per  cent,  hy- 
drochloric acid.  From  such  solution  it  is  reprecipitated  upon  neu- 
tralization, and  re-dissolved  by  an  excess  of  the  precipitant.  It  is 
insoluble  in  salt  solutions.  Its  solution  in  sodium  carbonate  upon 
dialysis  becomes  almost  entirely  soluble  in  water. 
