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C. G. KING, Ph.D.
JAMA. 1938;111(16):1462-1464. doi:10.1001/jama.1938.72790420004012.
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IDENTIFICATION  A primary requisite for studying the chemical nature of vitamin C was provided by Hoist and Frölich1 when they observed that the guinea pig could be used as an experimental animal for the study of scurvy. The experimental diets and general technic developed by Cohen and Mendel2 and La Mer, Campbell and Sherman3 then made it possible to measure antiscorbutic activity in a satisfactory quantitative manner, free from interference by deficiencies in other essential nutrients. Attempts to isolate the vitamin from natural products encountered great difficulty, however, because of its extreme sensitiveness to destruction by oxidation.By 1931 many investigators, particularly Zilva and his associates,4 Bezssonoff and his associates5 and King and his associates6 had succeeded in concentrating the vitamin to such a degree that approximately 1 to 2 mg. of solids daily served to protect young guinea pigs from scurvy. The isolation


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