Sulphur in protein bodies.

  • Osborne, Thomas B. (Thomas Burr), 1859-1929.
Date:
[1900]
Catalogue details

Licence: In copyright

Credit: Sulphur in protein bodies. 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.

    11/30 (page 453)
    The recent determination of sulphur, which is probably the most accurate, shows that amandin contains about 0.429 per cent, of sulphur. Table X.—Percentage of Loosely-Bound Sulphur in Amandin. One gram boiled with 30 p. c. NaOH, Zn and Five grams with 30 p. c. NaOH and Pb(C2H302)2 at.135°. Pb(CaH302)2 at 165°. 2 hours. 3 hours, O.ISO 0.217 0.172 O.165 The result obtained at the higher temperature and with the larger amount of substance is doubtless the most correct of the above figures, so that 0.217 per cent, may be taken as the pro- portion of sulphur which can be obtained from amandin, as sulphide. * Glycinin. The greater part of the protein matter of the soy bean is glycinin, a globulin described in a paper previously published (Osborne and Campbell, Report Conn. Agr. Expt. Station for 1897; also Jour. Amer. Chem. Soc. 20, 419). Careful redeter- minations of sulphur in several of the preparations, described in the paper cited, showed that the figures there given were nearly correct; the average of the new determinations gave 0.700 per cent, of sulphur against the published figure, 0.72 per cent. The total sulphur in glycinin is therefore 0.710 per cent. Table XI.—Percentage of Loosely-Bound Sulphur in Glycinin. One gram boiled with 30 p. c. NaOH, Zn and Five grams with 30 p. c. NaOH and Pb(C2H302)a. Pb(C2H302)2 at 165°. 7 1-2 hours. 3 hours. f O.32I 0.317 Preparation 2. J, °'3°5 | 0.274 ( 0.263 Preparation 14. 0.286 Since the result obtained with five grams of glycinin agrees closely with the higher figures obtained by boiling at the atmos- pheric pressure, we may safely assume that glycinin yields very nearly 0.320 per cent, of sulphur as sulphide.