﻿Concerned 
  in 
  the 
  Decomposition 
  of 
  Glucose 
  and 
  Mannitol. 
  299 
  

  

  seen 
  that 
  there 
  is 
  a 
  very 
  general 
  resemblance 
  between 
  the 
  curves, 
  and 
  

   especially 
  in 
  the 
  respect 
  that 
  they 
  all 
  show 
  the 
  formation 
  of 
  lactic 
  acid 
  to 
  be 
  

   independent 
  of 
  the 
  formation 
  of 
  the 
  other 
  products. 
  On 
  the 
  other 
  hand, 
  

   there 
  is 
  a 
  greater 
  divergence 
  of 
  the 
  curve 
  for 
  formic 
  acid 
  and 
  its 
  gaseous 
  

   products 
  from 
  the 
  other 
  curves 
  in 
  fig. 
  1 
  of 
  this 
  present 
  communication 
  than 
  

   there 
  is 
  in 
  any 
  of 
  the 
  previous 
  figures 
  given. 
  It 
  will 
  also 
  be 
  noticed 
  that 
  the 
  

   curve 
  for 
  formic 
  acid, 
  including 
  carbon 
  dioxide 
  and 
  hydrogen, 
  reaches 
  a 
  much 
  

   higher 
  level 
  here 
  than 
  it 
  did 
  previously. 
  

  

  In 
  the 
  upper 
  part 
  of 
  fig. 
  1 
  the 
  hydrogen 
  curve 
  is 
  seen 
  to 
  oscillate 
  in 
  a 
  

   manner 
  which 
  is 
  complementary 
  to 
  the 
  curve 
  for 
  alcohol 
  below. 
  This 
  

   constitutes 
  the 
  first 
  absolute 
  proof 
  that 
  alcohol 
  is 
  formed 
  from 
  glucose 
  by 
  

   reduction 
  in 
  vivo. 
  

  

  The 
  formation 
  of 
  alcohol 
  by 
  reduction 
  of 
  acetaldehyde 
  by 
  means 
  of 
  intra- 
  

   molecular 
  hydrogen 
  was 
  first 
  postulated 
  by 
  Kostycheff 
  for 
  alcoholic 
  fermenta- 
  

   tion 
  by 
  yeast, 
  and 
  later 
  by 
  the 
  writer 
  for 
  bacterial 
  fermentation. 
  Still 
  later 
  

   this 
  idea 
  was 
  incorporated 
  by 
  Neuberg 
  in 
  his 
  theory 
  of 
  alcoholic 
  fermentation, 
  

   but, 
  up 
  to 
  the 
  present, 
  the 
  proof 
  of 
  such 
  reduction 
  has 
  never 
  been 
  given 
  

   either 
  for 
  alcoholic 
  fermentation 
  by 
  bacteria 
  or 
  by 
  yeast, 
  although 
  Neuberg's 
  

   recent 
  researches 
  on 
  phytochemical 
  reduction 
  have 
  lent 
  considerable 
  support 
  

   to 
  the 
  view. 
  

  

  The 
  proof 
  that 
  alcohol 
  is 
  in 
  fact 
  formed 
  by 
  reduction 
  is 
  given 
  in 
  fig. 
  1. 
  

   Moreover, 
  it 
  will 
  be 
  observed 
  that 
  the 
  highest 
  point 
  in 
  the 
  alcohol 
  curve 
  is 
  

   in 
  the 
  column 
  for 
  Experiment 
  3. 
  In 
  this 
  case 
  almost 
  twice 
  as 
  much 
  alcohol 
  

   has 
  been 
  produced 
  as 
  in 
  the 
  normal 
  experiment 
  without 
  added 
  formate, 
  so 
  

   that 
  it 
  is 
  clear 
  that 
  when 
  formic 
  acid 
  is 
  added 
  the 
  hydrogen 
  which 
  is 
  liberated 
  

   by 
  its 
  decomposition 
  may 
  also 
  act 
  as 
  a 
  reducing 
  agent 
  and 
  thus 
  augment 
  the 
  

   yield 
  of 
  alcohol. 
  

  

  As 
  was 
  noted 
  in 
  the 
  introductory 
  remarks 
  to 
  this 
  communication, 
  only 
  in 
  

   one 
  out 
  of 
  the 
  four 
  experiments 
  with 
  formate 
  added 
  to 
  the 
  glucose 
  was 
  there 
  

   any 
  increase 
  in 
  the 
  yield 
  of 
  alcohol. 
  In 
  the 
  other 
  cases 
  there 
  is 
  a 
  very 
  

   marked 
  decrease. 
  Future 
  experiments 
  must 
  decide 
  what 
  the 
  conditions 
  are 
  

   which 
  enable 
  formic 
  acid 
  to 
  act 
  as 
  a 
  reducing 
  agent 
  in 
  the 
  fermentation 
  of 
  

   glucose. 
  

  

  Next 
  to 
  the 
  proof 
  of 
  the 
  participation 
  of 
  nascent 
  hydrogen 
  formed 
  by 
  the 
  

   fermentation 
  in 
  the 
  production 
  of 
  alcohol, 
  the 
  most 
  remarkable 
  result 
  is 
  the 
  

   demonstration 
  of 
  the 
  relation 
  of 
  added 
  formic 
  acid 
  to 
  the 
  production 
  of 
  

   formic 
  acid 
  from 
  glucose. 
  The 
  effect 
  of 
  the 
  formic 
  acid 
  added 
  in 
  the 
  form 
  of 
  

   calcium 
  formate 
  has 
  been 
  to 
  enormously 
  increase 
  the 
  production 
  of 
  hydrogen 
  

   and 
  carbon 
  dioxide 
  from 
  the 
  glucose. 
  

  

  We 
  are 
  accustomed 
  to 
  think 
  that 
  when 
  one 
  of 
  the 
  products 
  of 
  a 
  fermentation 
  

  

  