A text-book of physiological chemistry for students of medicine and physicians / By Charles E. Simon.

  • Simon, Charles E. (Charles Edmund), 1866-1927.
Date:
1907
Catalogue details

Licence: Public Domain Mark

Credit: A text-book of physiological chemistry for students of medicine and physicians / By Charles E. Simon. Source: Wellcome Collection.

Provider: This material has been provided by the Augustus C. Long Health Sciences Library at Columbia University and Columbia University Libraries/Information Services, through the Medical Heritage Library. The original may be consulted at the the Augustus C. Long Health Sciences Library at Columbia University and Columbia University.

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    hydrogen in the group CH—NH, which in turn is structurally closely related to hydrocyanic acid. In accordance with these considera- tions, we thus find that amygdalin, CwHwNOu, is decomposed into glucose, hydrocyanic acid, and benzaldehyde, as shown in the equa- tion : C,0IT2,NOU + 2H20 = 2C.H, A + QHj.COH + CNH. Solanin, CwN70NO16, similarly yields glucose and solanidin, C^- H39NO. Mannides.—Like the carbohydrates proper, the mannides or man- nitides, which also occur widely distributed in the vegetable world, are likewise derived from the aldehyde radicle that is formed by chlorophyl under the influence of sunlight. They differ from the glucosides in yielding mannite, C6H1406, instead of glucose, on hydrolytic decomposition. The origin of mannite from formic alde- hyde may be represented by the equation : 6CH,0 + 2H = C6HM06- On the other hand, mannite may result from glucose as the result of the specific activity of certain cells, as is shown by the equation : 13C,H1206 + 611,0 = 12C6H,A + 6CO,. Synthesis of the Fats.—The fats which are found in plants are, like the carbohydrates, derived from carbon dioxide and water, and in all likelihood are formed also synthetically through the agency of the chlorophyl. The mechanism, however, by which these syntheses are effected is not so clear. It is probable that they result from the union of carbon dioxide and water, as shown by the equations: (1) 3C02 + 4H20 = C,H803 Glycerin. + 70. (2) 34CO, + 34H30 = c18ir36o. Stearic acid. + 16CHA + 680. Formic acid. (3) C3H5(OH): Glycerin. , + 3C„H$5O.OH = C3H5(O.C,8H350)3 Stearic acid. Stearin. + 3H20. This supposition is strengthened by the observation that during certain phases in the life of some plants an actual transformation of carbohydrates into fats takes place. In the fruits and leaves of the olive tree, for example, a large amount of mannite gradually disappears during the months of September and October, and is replaced by oil. This transformation could be explained upon the basis of the equations just given, or by the assumption that the oil results from mannite through a loss of water and carbon dioxide, as suggested by the equation : 11C6H,A = C51H<,A + 30H2O + 15C02. In any event, the system H20 + CO,, which gives rise to the formation of formic aldehyde and glucose, must also be regarded as the fundamental basis in the synthesis of fats.