IAVDUSTRIAL A,VD EXGINEERIAVG CHEMISTRY
1176;
tion of glycerol in yeast fermentation which does not conflict with experimental facts, has been put forward b y Neuberg (18). H e conceived the yeast fermentation of glucose as being capable of taking place in three different ways, depending on the conditions of culture. All three of these forms involve the breakdown of the hexose into two molecules of hydrated methylglyoxal, which is then transformed to pyruvic acid, setting free active hydrogen according to the equation: C6H1206 +2CHaCO CH(0H)z +2CH3CO COOH
+ 2H2
The pyruvic acid is then attacked by the enzyme carboxylase, breaking it down into acetaldehyde and carbon dioxide as folloTT’s: CH3 CO.COOH
+CH3 CHO + COz
I n a normal alcoholic fermentation the acetaldehyde is then reduced b y the active hydrogen, giving ethyl alcohol, the complete process being represented by the following equations : C6H12O6 + 2CH3CO. CH(0H)z + 2CH3, CO . COOH 2CH3, CO. COOH +2CH3. CHO 2C02 2CH3, CHO 2Hz +2C2Hs. OH
+
+
C6H12Oe
--+ 2ClH,OH
+ 2Hz
+ 2C02
I n the presence of sodium bisulfite, for example, the aldehyde is fixed and removed almost completely from reaction with the hydrogen, which then attacks the methylglyoxal, giving rise to glycerol, according t o the equations:
__
CnHI>Or+2CH3 CO CHiOH), +CH,” CO COOH 4- H7 CH3”CO COOH CH3 CHO-+ C 0 2 CH3 CHO NaHS03 +CH3 CHO HS03Sa CH3 CO CH(0H)z HA+CH3Hj(OH)3
+
+
I n the presence of alkalies a third series of reactions occurs in which two molecules of the aldehyde, following CanniZaro’s reaction, undergo mutual oxidation and reduction, giving rise t o a molecule each of et’hylalcohol and acetic acid, thus permitting t’lie active hydrogen to react Tvith methylglyoxal to form glycerol, according to the equations: 2CBH1206 +4CH3. CO. CH(0H)z +2CH3. CO. COOH+2H> 2CH3, CO , COOH +2CH3. CHO f 2COa
Vol. 22, No. 11
+ CH3. COOH
2CH3. CHO +CzHsOH 2CH3. CO. CH(OHj2 2H2
+
2C6Hiz06
+2C3Ha(OH)3
+2CsHj(OH)3 + CzHbOH
+ CHJCOOH + 2C02
These mechanisms express quite well what actually takes place in yeast’ fermentations under varying conditions. It should be st’ated, however, that the existence of methylglyoxal in any of its many labile forms in the alcoholic fermentations is largely hypothetical, as it has never been definitely isolated in quantity in the course of fermentation studies. The extent to which the fermentation process for the production of glycerol is being used today is not known definitely, but it is certainly much less than a decade ago, owing to the comparatively plentiful supply of fat products and to t h e increased use of synthetic glycols. Nevertheless, the process is available and m u l d undoubtedly’prove very valusble in time of emergency or if the world were faced with a depleted supply of natural fats. L i t e r a t u r e Cited (1) (2) (3) (4)
Xmelung, Chem.-Zlg., 6 4 , 118 (1930). Bernhauer, Z . phjsiol. Cizem., 177, 86, 270 (1928). Bleyer, German Patent 434,729 (1936). Boutroux, Compl. r e n d . , 86, 60.5 (1878); 91, 236 (1853). ( 5 ) Cahn, French Patents 675,236, 675,237 (1929). (6) Calmette, Gerrnm Patent 129,161 (March 1, 1902). (7) Connstein and L.idecke, Bev., 62, 1383 (1919). (8) Currie. J . B i d Chem.. 31, 15 (1917). (9) Eoff, Linder, and Ueyer, J . 1x0. Esc. CHEI., 11, 8 4 2 (1919). (10) Falck. G e r m i n Patent 426,926 (19261. (11) Fernbich, Compt. r e n d , 131, 1214 (1933). (12) Fernbich and Yuill, U. S. Patents 1,631,965, 1,691,966 (1938). (13) Fulmer and W e r k m m , “Chemical Action of hlicro5rgnnisms,” p . 6, 129, Charles C. Tnomas, Springfield, I l l , 1930. (14) Henneberg, “Handbuch der Garungsbacteriologie,” Val. 11, p . 385, Berlin, 1926. (15) Lafar, “Handbuch der Technischen hlykologie,” Vol. I\’, p . 242, Jena, 1905-7. (16) XIiy, Herrick, Moyer, and Hellbach, IND. Exc. CHBM.,21,’1198 (1929). 117) Muller. Biochem. Z.. 199., 136 (1928): . . 205.. 11 (1929). . (181 Seuberg, I b i d . , 96, 175 (1919); 98, 141 (1919); 106, 281 (1920). (19) pottevin, compt. r e n d . , 131, 1215 (1900). (20) Scheele, Creil’s chem. .Ann., I, 3 (1787). (21) Schweizer, Chimie et industrie, 6, 149 (1921).
iii; 2:i t2i)
(231 126) (27) (28)
Van, Compl,
(1916),
6 6 , 1091 (1867),
Wehmer, Bull. soc. c 4 i m . . 9, 725 (1893); Compt. r e n d . , 117, 332 (1893). Wehmer, U. S. Patent 515,033 (1894). Zahorski, U. S . Patent 1,066,358 (1913). Zerner, Ber., 63, 325 (1930).
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Uses of Radium The principal use of radium, for the treatment of cancer, is quite well known, b u t there are various other uses for this rare and costly metal which are not so often referred to, according to the United States Bureau of Mines. Substantial amounts of radium, estimated a t as much as 10 per cent of the production in some years, are employed for the manufacture of luminous paints used on watch and clock dials, electric switch buttons, keyholes, and like products. War-time radium luminous material eliminated lights t h a t would have betrayed the presence of troops to the enemy. Maurice Curie has described experiments that indicate the profitable use of radioactive elements as fertilizers and for agricultural purposes. Tailings from Cornish ores were formerly shipped to France as fertilizers, but opinion in this country is that no good effect is obtained from radioactive substances as fertilizers. Food-preservative receptacles have been made from mixtures of radiferous (carnotite) ore with white Portland cement, the idea beitg t o prevent bacterial action through radioactivity. A few tons of carnotite are used annually in the manufacture of vessels designed to produce radioactive drinking water. Radium emanation has been used in testing the minute leak-
age of air through rubberized fabric for gas masks, and there are numerous scientific and technical problems in which radioactivity may be employed as a convenient indicator of conditions that the most refined mechanical measurements fail t o reveal. Radium is used to eliminate fire hazards in a large Russian rubber factory by preventing sparks of static electricity. I n the laboratory radium has wrought a revolution in many of the preconceived notions of scientists. The existence of radium and of its decomposition products proves the transmutation of metals as an accomplished fact; and though the process of decomposition is far too slow t o satisfy the commerical need for prompt returns, the fact that an atom, formerly considered an immutable and indivisible unit of matter, is actually a complex structure that may be altered t o other atoms less complex goes far toward realizing the dream of alchemists. The study of the spontaneous disintegration of radioactive elements has given the scientific world an insight into the actual composition of matter; and radium rays, especially the alpha particles, have given physicists a new instrument with which t o investigate the fundamental properties of material substance.