Am.  Jour.  Pharm.) 
January.  1900.  J 
Editorial. 
43 
which  can  be  isolated,  so  that  the  zymase  of  yeast  and  the  diastase  of  Asperi- 
gillus oryzce  correspond  to  the  diastase  of  barley  or  the  emulsin  in  almond. 
At  the  same  time  that  the  enzyme  theory  of  fermentation  is  being  developed  an 
equally  interesting  phase  of  the  fermentation  question  from  the  biological  point 
of  view  is  coming  to  light  in  what  is  known  as  symbiotic  fermentation.  It  was 
Schwendener  who,  in  1S69.  first  conclusively  showed  the  peculiar  relationship 
existing  between  the  algae  and  fungi  in  what  constitute  the  group  of  plants  known 
as  Lichens.  When  certain  algae  and  certain  fungi  were  brought  together  under 
proper  conditions,  this  relationship  was  shown  to  be  not  one  of  parasitism,  but 
one  of  mutual  benefit,  and  termed  symbiosis.  Since  that  time  a  symbiotic  rela- 
tioushio  in  a  large  number  of  plants,  as  well  as  animals,  has  been  observed. 
A  good  case  of  symbiosis  is  observed  in  the  no  lules  on  the  roots  of  leguminous 
plants  which  are  filled  with  bacteria.-  These  latter  penetrate  the  root  hairs  and 
perform  in  the  living  cells  of  the  higher  plant  functions,  which  are  of  decided 
benefit.  In  the  green  infusoria,  hydra,  sponges,  etc.,  is  observed  a  symbiotic 
relationship  between  the  alga  and  animal. 
The  investigators  of  recent  years  have  shown  that  in  the  alcoholic  fermenta- 
tion of  starch  at  least  two  organisms  are  at  work,  each  doing  its  share  towards 
producing  the  final  products.  "  Van  Laer  has  called  attention  to  the  symbiotic 
CD-existence  of  two  yeasts  in  many  beers,  explaining  certain  peculiar  after- 
fermentations  as  due  to  the  action  of  yeast  on  the  medium  improved  for  it 
by  the  other.  The  Japanese  have  long  been  in  the  habit  of  brewing  a  peculiar 
fermented  liquor  known  as  rice-wine  or  sake.  Rice  grains  are  steamed,  and  when 
cool  infected  with  a  mould  fungus  now  known  as  Aspergillus  oryzce.  When 
the  rice  is  quite  mouldy,  at  which  time  it  emits  a  peculiar  odor  like  pineapples, 
the  starch  is  found  to  be  turning  rapidly  into  sugar,  under  the  action  of  a 
diastatic  enzyme  secreted  by  the  fungus.  This  decomposing  rice  is  then  placed 
in  water  and  exposed  to  the  action  of  a  yeast,  which  rapidly  ferments  the  su^ar, 
and  the  alcoholic  sake  results.  So  closely  is  the  yeast  associated  with  the 
Asperigillus  that,  in  practice,  the  alcoholic  fermentation  commences  soon  after 
the  enzyme  of  the  Asperigillus  begins  to  hydrolyze  the  starch  of  the  rice,  and 
for  some  time  a  con  trovers}- existed  as  to  whether  the  yeast  was  not  really  apart 
of  the  life  history  of  the  Asperigillus.  Several  observers  have  now  shown, 
however,  that  we  have  here  a  striking  case  of  symbiosis."1  Similar  cases  of 
symbiosis  are  observed  in  the  ginger-beer  plant,  only  yeast  and  bacteria  are 
here  associated  together,  forming  the  clumps  in  the  fermenting  solutions. 
A  very  complex  system  of  symbiosis  has  been  shown  by  the  experiments  of 
Omeliansky  to  be  concerned  in  the  circulation  of  nitrogen  in  nature.  This 
author  found  that  "  if  Nitrosomonas — the  bacteria  which  oxidizes  ammonia  to 
nitric  acid  and  Nitrobacier,  the  bacterium  which  further  oxidizes  nitrous  to 
nitric  acid — be  sown  together  or  separately  on  a  medium  containing  organic 
nitrogen,  no  growth  or  change  takes  place.  But  if  a  bacterium  capable  of  de- 
composing the  organic  nitrogenous  medium,  e.g.,  Bacillus  ramosus,  is  added 
to  the  above-mentioned  Nitrosomonas  and  jVitrobacler,  the  associated  three 
organisms  are  able  to  carry  out  all  the  processes  and  complete  the  cycle  of 
1Ottokar  Shieweck  (Centr.  Bakt.  Par.,  I,  ii,  7S2)  supposes  that  the  fermeutation  is  caused 
by  special  yeasts,  in  part  true  yeasts  {Saccharomyces  anomalies  and  a  yeast  with  round  spores), 
which  are  mixed  with  Asperigillus.  See  also  Chem.  News,  1S99,  p.  174,  and  Jour.  Chem.  Soc. 
(abs.),  1898.  p.  398. 
