On chemical changes in their relation to micro-organisms / E. Frankland.

  • Frankland, Edward, 1825-1899.
Date:
1885
Catalogue details

Licence: Public Domain Mark

Credit: On chemical changes in their relation to micro-organisms / E. Frankland. Source: Wellcome Collection.

Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.

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    chiefly from them in the absence of organised matter, and in the non- increase of the ferment during its action upon the fermentescible substance. I will, therefore, here briefly indicate those fermentations which are the results of so-called contact action, and not of micro- organisms :— 1. Tx’ansformation of starch into glucose and dextrin, or hydrated maltose by diastase— 4C6H,o05 + 3OH2 = CoH,o05 -f Starch. Dextrin. Glucose. Hoppe-Seyler gives this equation. The identity of this glucose with grape-sugar has been called in question by Nasse. 2. Transformation of cane sugar into glucose (dextrose) and levu- lose— CisHo^On + OH2 = C6H.,06 -f CeHi.Oe. Cane-sugar. Glucose. Levulose. Berthelot has shown that this change is efiected by a soluble fer- ment accompanying yeast, and also found in the bodies of bees and in bee-bread. It has been named “ Invertin.” 3. The transformation of glucosides :— (a.) Amygdalin into glucose, benzoic aldehyde, and hydrocyanic acid— C^oH^^NOn -f 2OH2 = 2C6H12O6 + CtHcO -h CNH. Amygdalin. Glucose. Benzoic Hydrocyanic aldehyde. acid. (b.) Salicin into glucose and saligenin— CisHisOy -}- OH2 — C6lli206 + CvHeOj. Salicin. Glucose. Saligenin. (c.) Arbutin into glucose and hydroquinone— C12H16O7 -|- OH2 = C6H12O6 + C6H6O2. (d.) Helicin (product of the oxidation of salicin) into glucose and salicylic hydride (product of the oxidation of saligem’n)— CisHisOv -}- OH2 = C/6Hi206 -f- CvHeOz* Helicin. Glucose. Salicylic hydride. (e.) Phloridzin (in bark of apple and pear trees) splits into glucose and phloretin— C21H24O10 + OH2 = Cf,Hi206 -f- C15H14O5. Phloridzin. Glucose. Phloretin.