Photolysis of
Various Complex Sugars (Bioses and Trioses) by Ultra-violet Rays. D. BERTHELOT and H. GAUDECHON. (Corn/&s @endus, clv, 15o6.&Ten per cent. solutions of maltose and lactose exposed to sunlight ( I > o.2gw) for six m'onths suffered no change.
When exposed to ultra-violet rays of relatively long wavelength ( 1 > 0.25~) there was decomposition in two stages, and gases were evolved, two volumes of carbon monoxide to one volume of hydrogen.
The solutions remained neutral, did not reduce Fehling's solution in the cold, and had only a slight effect on ammoniacal silver nitrate.
When exposed to the extreme ultra-violet radiation the solutions b'ecame acid and strongly reducing, and carbon dioxide and methane were among the gases evolved.
The gases from maltose contained: carbon monoxide 29, hydrogen 51, carbon dioxide 14, and methane 6 per cent. Lactose, trehalose, and gentiobiose gave almost the same proportions.
Trioses are decomposed by the radiation of longer wave-length into two molecules of aldose and one of kevulose, the composition of the gas being approximately three of carbon monoxide to one of hydrogen. This was also observed with raffinose, melezitose, and gentianose.
When the rays of shorter wave-lengths are used the composition of the gases changes in the same respects as in the case of the bioses.
It is suggested that, since ultra-violet radiations can perform all the functions of enzymes in the scission of sugars and of fats, the reason for the action of enzymes is not to be sought in their chemical structure, but in their vibratory rhythm.