. The Alumni journal. Columbia University. College of Pharmacy; Pharmacology. 74 THE ALUMNI JOURNAL CHLOROPHYLL.* By Curt P. Wimmer, , (Continued.) The question as to whether the chlorophylls of all plants are alike was answered in the affirmative after an examination of several hun- dred different plant extracts. Discrepancies in the results were found to he due to an enzyme action. When a green plant is extracted with alcohol, an enzyme which accompanies the chlorophyll, becomes active and alcoholizes it; the phytol rest is replaced quantitatively by C2H5. The solvent will show a
. The Alumni journal. Columbia University. College of Pharmacy; Pharmacology. 74 THE ALUMNI JOURNAL CHLOROPHYLL.* By Curt P. Wimmer, , (Continued.) The question as to whether the chlorophylls of all plants are alike was answered in the affirmative after an examination of several hun- dred different plant extracts. Discrepancies in the results were found to he due to an enzyme action. When a green plant is extracted with alcohol, an enzyme which accompanies the chlorophyll, becomes active and alcoholizes it; the phytol rest is replaced quantitatively by C2H5. The solvent will show a brownish color. This can be avoided by a rapid extraction, or by addition of a small amount of alkali. Some plants are richer in chlorophyllase than others. Water enhances the action of this enzyme, wood alcohol retards it. Chlorophyll and Chlo- rophyllase appear to be specific for one another. Other esters, such as spermacetie, were not affected by chlorophyll, nor did other en- zymes, such as pancratin, split chlorphyll. The enzyme not only splits chlorophyll, but also forms it. Upon addition of phytol to phytol free chlorophyll esterification took place; this enzyme, no doubt, plays an important part in the formation of chlorophyll in the plant. The chlorophyll of all plants showed the presence of Mg- and of 1/3 of its molecule of phytol. The final reaction products of alkalis on phaeophytine were two substances which are the components of chlorophyll: one bluish green, photochlorine, the other yellow-green, phytorhodine, which were isolated and analyzed. A structural for- mula was found for phytol. Absolutely pure chlorophyll was obtained and found to be crystal- lizable, forming a blue-black powder with metallic lustre, readily soluble in alcohol and ether, but insoluble in benzine. The solutions are blue-green. It contains 5% MgO in its ash. Its composition cor- responds to C,.-H,20,,N4Mg and most likely possesses the following nucleus:. r=c ^ -o- *Read at the January me
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