On expressed yeast-cell plasma (Buchner's 'zymase') / by Allan MacFadyen, G. Harris Morris and Sydney Rowland.

  • Macfayden, Allan, 1860-1907
Date:
[1900]
Catalogue details

Licence: In copyright

Credit: On expressed yeast-cell plasma (Buchner's 'zymase') / by Allan MacFadyen, G. Harris Morris and Sydney Rowland. 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.

    9/21 (page 255)
    placement of salt solution. The volume of gas evolved is expressed in this and the following tables on 100 c.c. of juice, although the quantity actually used was, as a rule, either 25 to 40 c.c. It will be noticed that in nearly every instance more gas was obtained from the auto-fermentation of the juice than from the fermentation in the presence of cane-sugar. This was usually the case with the juice from the yeasts of A, C, and D breweries; how far it is due to the distinctive character of the yeasts or to the high sugar concentx’ation we are at present not prepared to say. Another point to be noted is the great variation in the activity of the juice fi’om different samples of yeast. We noticed this throughout the whole of our experiments, l)ut we are unable to correlate it with any of the physical properties of the juice, such as gravity, &c. It will also be seen that by far the greater part of the action is at an end after twenty-four hours, thei’e being either no further increase in the amount of gas evolved, or comparatively little. This we also found common to the majority of oui' experiments, as will be seen from subsequent tables. Table I.—Volimxe of Carbon Dioxide evolved by Cell Juice from different Yeivsts, with and without the addition of Cane-sugar. Source of yeast. i Age of yeast from eolleotion. 1 Carbon dioxide from 100 c.c. of juice. After 24 hours. After 48 hours. Alone. With 40 per cent, sugar. Alone. With 40 per cent, sugar. I C.C. C.C. C.C. C.C. A* Fresli ' 520 280 600 472 A* 1 dav 240 808 — — A* 2 days 133 164 — — A* Fresh 308 186 308 324 A* Fresh 400 228 400 340 A* 1 day 285 270 285 320 A* 1 day 1 162 84 162 150 At 2 days , 990 234 990 290 At Fresli 90 170 — — At 3 days 760 560 788 592 A:t Fresh I 900 2165 — — A* 5 days ] 280 220 — — C* 1 day 550 180 — — ct 1 day 540 100 — — c* 3 days j 160 200 — — ' A* 7 days 120 200 — — A* 1 day 1 65 90 * Toluol used as antiseptic. f Sodium arseuite used as antiseptic.