The soluble ferments and fermentation.

  • Green, J. Reynolds (Joseph Reynolds), 1848-1914.
Date:
1899
Catalogue details

Licence: Public Domain Mark

Credit: The soluble ferments and fermentation. 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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    digestion. These various functions must necessarily push the process of secretion somewhat into the background, or at any rate obscure the appearances. We have in Guignard's researches upon myrosin some facts brought to light which indicate an essential similarity of the process to that already described. The cells in the roots of the horse-radish and other plants which contain the myrosin can be recognised by their peculiar granular contents, which give a very marked reaction with Millon's reagent, the colour produced being much more intense than that which is developed when this fluid comes into contact with proteids. Guignard has demonstrated a close correspondence between the degree of this granularity and the amount of enzyme in the cells. The process of the secretion of diastase in the cells of foliage leaves is hardly at all known. Some researches carried out by A. Meyer seem to indicate that it does not arise in the ordinary protoplasm of the cell, but is formed in the chromatophore or chlorophyll grain. The same thing has been noted in connection with the parts of the plant which are not green, where the diastase appears to arise in the leucoplastids which form the grains of starch. The hypothesis is largely based upon the appearances presented by grains which have been partially dissolved by the enzyme. Meyer describes many cases in which the starch grains were attacked most ener- getically where the sheath formed by the stroma of the plastid was thickest. In Ii^is he frequently found the side of the grain eaten out to some extent where the leucoplast was in contact with it. Meyer's view has been confirmed by Salter, who made a series of observations on the starch grains of Pellionia. He says with reference to these, that when he examined grains in process of solution, he found the action had proceeded furthest at the point where the plastid w^as situated. The latter had practically eaten its way, in many cases, into the substance of the starch grain. Though in so many cases we are able to associate the secretion of enzymes with the formation of the coarse granules described, it by no means follows that the latter are the