INDEX.

Acetaldehyde, as an intermediate product of alcoholic fermentation, 110. — reduction of by yeast, 110.

Acetone-yeast, 38.

Alanine, as an intermediate product of alcoholic fermentation, 115.

Alcohol, formation of, from sugar by alkalis, 97.

Alcoholic fermentation, attempts to separate enzymes of, from yeast- cell, 15. — — by-products of, 85. — — equation of, 51. — — Gay-Lussac's theory of, 4. — — Iwanoff's theory of, 106. — — kinetics of, 120, 128. — — Lavoisier's views on, 3. — — Liebig's theory of, 8. — — Nägeli's theory of, 15. — — of the amino-acids, 87. — — — — theory of, 91. — — Pasteur's researches on, 11. — — Traube's enzyme theory of, 14.

Alkalis, effect of, on hexoses, 96.

Amino-acids, alcoholic fermentation of, 87. — stereoisomerides of, fermented at different rates by yeast, 89.

d-Amyl alcohol, formation of from isoleucine, 86.

Antiprotease in yeast-juice, 42, 65.

Antiseptics, action of, on yeast-juice, 19, 36.

Arsenate, effect of, on fermentation by yeast-juice and zymin, 73. — — on autofermentation of yeast-juice, 80. — nature of acceleration produced by, 78.

Arsenite, effect of, on fermentation by yeast-juice, 77. — — on autofermentation of yeast-juice, 80. — nature of acceleration produced by, 78.

Autofermentation of yeast-juice, 33, 119. — — effect of arsenates and arsenites on, 80.

Baeyer's theory of fermentation, 99.

Boiled yeast-juice, effect of, on fermentation by yeast-juice, 41.

Carboxylase, 81, 93. — relation of to alcoholic fermentation, 83.

Co-enzyme, effect of electric current on, 67. — enzymic destruction of, 63. — of yeast-juice, 59. — precipitation of, by ferric hydroxide, 67. — properties of, 63. — removal of, from yeast-juice, 59. — separation from phosphate and hexosephosphate, 67.

Concentration of sugar, effect of, on fermentation by yeast-juice, 34.

Dauerhefe, 38.

Diastatic enzyme of yeast-juice, 33.

Dihydroxyacetone, fermentability of, 104. — formation of, in fermentation, 105.

Dried yeast (Lebedeff), 24, 38.

Endotryptase, 20.

Enzyme action, laws of, 121.

Enzymes, combined with protoplasm, 126.

Equation of alcoholic fermentation, 51.

Fermentation by yeast-juice, causes of cessation of, 64.

Fermenting complex, 63. — power of yeast-juice, estimation of, 27.

Formaldehyde, production of in alcoholic fermentation, 117.

Formic acid theory of fermentation, 114.

Fructose, fermentation of, by yeast-juice, 32. — — in presence of phosphate, 73. — relation of, to fermenting complex, 74.

Fusel oil, formation of, from amino-acids, 85.

Galactose, fermentation of, by yeast, 131. — fermentation of, by yeast-juice, 32.

Glucose, fermentation of, by yeast-juice, 32.

Glyceraldehyde, fermentability of, 104.

Glyceric acid, fermentation of, 108.

Glycerol, formation in fermentation, 95.

Glycogen as an intermediate product of alcoholic fermentation, 116. — fermentation of, by yeast-juice, 33. — removal of, from yeast, 39.

Grinding of yeast by hand, 22. — — — mechanical, 23.

Glutamic acid, decomposition of, by yeast, 90.

Hefanol, 38.

Hexosediphosphoric acid phenylhydrazone, hydrazine salt of, 50.

Hexosemonophosphoric acid osazone, hydrazine salt of, 50.

Hexosephosphatase, 54.

— effect of arsenate and arsenite on action of, 79.

Hexosephosphate, constitution of, 51. — enzymic decomposition of, in yeast-juice, 56. — — hydrolysis of, 51. — formation of, 48. — hydrolysis of, by acids, 49. — preparation of, 48. — properties of, 49. — theory of formation of, 57, 117,

Hexoses, action of alkalis on, 96,

Isoamyl alcohol, formation from leucine, 87.

Isoleucine, decomposition of, by yeast, 87.

α-Ketonic acids, fermentation of, 81.

Lactic acid, destruction of, by yeast-juice, 102. — — formation from sugars by alkalis, 97. — — — of, in yeast-juice, 102. — — non-fermentability of, by yeast, 103. — — theory of fermentation, 102.

Leucine, decomposition of, by yeast, 87.

Maceration extract, preparation of, 25.

Mannose, fermentation of, by yeast, 131. — — of by yeast-juice, 32.

Methylglyoxal, conversion of, into lactic acid, 101. — non-fermentability of, 104. — as an intermediate product of alcoholic fermentation, 113.

Oxalacetic acid, formation of, from tartaric acid, 101.

Permanent yeast, 38.

Phenylethyl alcohol, 88.

Phosphate, changes of, in alcoholic fermentation, 47. — effect of, on fermentation by yeast-juice, 42. — — — — — by zymin, 46. — — — — — of fructose, 73. — — of on total fermentation of yeast-juice, 54. — influence on fermentation of concentration of, 71. — inhibition by, 71.

Phosphates, essential for alcoholic fermentation, 55.

Proteoclastic enzyme of yeast, 20.

Protoplasmic theory of activity of yeast-juice, 19.

Pyruvic acid, fermentation of, 81. — — theory of fermentation, 109.

Rate of fermentation, controlling factors of, 119.

Reductase, intervention of, in alcoholic fermentation, 111.

Serum, effect of, on fermentation by yeast-juice, 41.

Succinic acid, formation of, in fermentation, 89. — — formed from glutamic acid by yeast, 90.

Synthetic enzyme in yeast-juice, 32.

Temperature coefficient of fermentation by yeast, 129. — — — — by zymin, 122. — — — esterification of phosphoric acid by yeast extract, 58.

Tryptophol, 88.

Tyrosol, 88.

Wohl's theory of fermentation, 101.

Yeast, action of toluene on, 124. — and yeast-juice, fermentation by, compared, 29, 124. — discovery of the vegetable nature of, 5. — fermentation by, 127. — — of different sugars by, 130. — influence of concentration of dextrose on fermentation by, 128. — — — — of, on rate of fermentation, 129. — — of toluene on autofermentation of, 126. — nature of the process of fermentation by, 123. — temperature coefficient of fermentation by, 129. — theories of fermentation by, 133.

Yeast-juice and yeast, fermenting powers compared, 29, 124. — co-enzyme of, 59. — dialysis of, 59, 62. — effect of arsenate on fermentation by, 75. — — of concentration of sugar on fermentation by, 34. — — of dilution on fermentation by, 35. — — of phosphate on total fermentation, produced by, 54. — estimation of fermenting power of, 27. — evaporation of, 37. — filtration of through gelatin filter, 59. — precipitation of, 38. — preparation of, 21. — properties of, 19. — ratio of alcohol and carbon dioxide, produced by, 30. — synthesis of complex carbohydrate by, 31. — variation of rate of fermentation by, with concentration of sugar, 121.

Zymase, Buchner's discovery of, 16. — enzymic destruction of, 64. — properties of, 18. — regeneration of inactive, 64. — separation from co-enzyme, 59.

Zymin, 21, 38. — fermentation by, 39. — rate of fermentation by, 39. — temperature coefficient of fermentation by, 122.

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