580       Pharbitis  Triloba  as  a  Source  of    Jalap.''     {'^"'nov'  iSs^''"'" 
PHARBITIS  TKILOBA  AS  A  SOUKCE  OF  "  JALAP/^ 
In  the  second  part  of  Vol.  I  of  the  "  Mitteilungen  aus  der  medicin- 
ischen  Facultat  der  kaiserlich  Japanischen  Universitat/^  published  at 
Tokio,  M.  K.  Hyrano  discusses  the  value  of  this  species,  a  native  of 
Japan,  for  medicinal  purposes.  He  states  that  the  purgative  proper- 
ties of  the  official  species  of  convolvulaceae  are  due  to  the  presence 
either  of  convolvulin  CgiH^oOig  or  of  orizabin  Cg^HggOjg  (jalapin  of 
W.  Meyer).  The  drugs  used  in  commerce  are  jalap  root^  orizaba  root, 
scammony  root  and  turbit  root.  Jalap  root  contains  convolvulin,  but 
that  of  Ipomoea  0ma6e/isis  jalapin,  which  has  a  homologous  composition 
with  convolvulin,  but  differs  from  it  by  its  solubility  in  ether  and 
chloroform.  Scammony  root  also  contains  orizabin ;  the  resin  con- 
tained in  turbit  root  appears  to  consist  at  least  partially  of  the  same 
substance  as  that  of  orizaba  root.  The  purgative  properties  of  the 
seeds  of  Pharbitis  Nil  are  due  to  convolvulin.  The  native  name  of 
Pharbitis  triloba,  of  Japan,  is  ^'  asagawo,''  and  its  seeds  have  long  been 
used  as  a  purgative  under  the  name  ^"  kengashi." 
A  full  botanical  description  of  the  plant  and,  in  particular,  of  the 
seeds,  follows. 
To  extract  the  active  principle,  400  grams  of  the  finely-powdered 
seeds  were  twice  boiled  in  alcohol  of  90  per  cent.,  filtered,  and  the  pure 
filtrate  decomposed  by  acetate  of  lead.  The  liquid  filtered  from  the 
lead  precipitate,  after  removing  the  excess  of  lead  by  sulphuretted  hy- 
drogen, was  evaporated  in  the  water-bath,  by  which  a  resinous  mass 
was  obtained.  This  was  kneaded  in  warm  water  in  order  to  rid  the 
resin  from  its  soluble  impurities ;  and  it  was  further  purified  by  again 
dissolving  in  alcohol  and  precipitating  by  water.  The  resin  thus 
finally  obtained  in  the  water-bath  weighed  27  grams.  It  was  a  brittle 
friable  substance ;  ether  extracted  from  it  10*3  per  cent,  of  almdst 
pure  oil.  The  portion  remaining  insoluble  in  ether  gave  all  the  reac- 
tions of  convolvulin.  The  pure  resin  was  easily  soluble  in  alcohol, 
but  insoluble  in  bisulphide  of  carbon  or  chloroform ;  after  treatment 
with  dilute  hydrochloric  acid  it  reduced  alkaline  copper  solution.  Like 
convolvulin,  it  exhibited  the  chemical  properties  of  a  glucoside,  split- 
ting up,  under  the  action  of  mineral  acids,  into  sugar  and  con  vol  vu- 
lionic  acid  C13H23O3,  which  forms  a  crystallizable  salt  with  barium, 
soluble  with  difficulty  in  water,  but  readily  in  alcohol. 
The  author  concludes  that  the  resin  obtained  from  Pharbitis  triloba 
may  be  used  oflficinally  in  the  place  of  resina  jalapse. — Phar.  Jour,  and 
Trans.,  October  6,  p.  270. 
