PEKELHARING, CORNELIS ADRIANUS

(b. Zaandam, Holland, 19 July 1848; d. Utrecht, Holland, 18 September 1922)

physiological chemistry, medicine.

Pekelharing was the son of Cornelis Pekelharing, a physician, and Johanna van Ree. In 1866 he became a medical student at the University of Leiden, where his interests ranged from chemistry and physics to social and religious questions. The well-known physiologist Adriaan Heynsius appointed him his assistant from 1871 to 1876. A skilled and conscientious laboratory worker, Pekelharing became a licensed physician in 1872 and established a practice in Leiden. In 1873 he married Willemina Geertruida Campert; they had five children. Pekelharing received the M.D. degree in 1877 after a masterful defense of his dissertation on the determination of urea in blood and tissues.

Pekelharing returned to the laboratory after his appointment in 1878 as instructor in physiology and anatomy at the School of Veterinary Medicine in Utrecht. Here he developed his research interests, many of which he maintained throughout his life, without neglecting his teaching duties. Protein digestion in the stomach and its end product, which he called pepton, were thoroughly investigated by Pekelharing’s group. His many publications on this subject became the center of much controversy in Europe. He also elucidated the protein nature of pepsin. The study of anthrax led him to take up bacteriology. He went to Leipzig to study with Julius Cohnheim, a student of Virchow’s, and in 1886 visited Koch in Berlin. In 1881 Pekelharing was appointed professor of pathology and anatomy at the University of Utrecht. In 1888 his assignment was changed to physiological chemistry and histology. With the neurologist C. Winkler and a growing number of medical students, Pekelharing studied the role of leukocytes in inflammation and phagocytosis. He continued his work with anthrax bacilli and spores. Subsequent investigations included the role of calcium in blood clotting, arteriosclerosis, urine pigments, enzyme precursors, intestinal iron absorption, and hemoglobin and glycogen in oysters.

Pekelharing became interested in nutrition in 1886, when he and Winkler were sent to the Dutch East Indies to investigate the cause of beriberi. They were joined by Christiaan Eijkman. In accordance with the general conviction of his time, Pekelharing looked for and found a microorganism that he believed to be the causative agent of beriberi. Nevertheless, he was not totally satisfied with his findings; and upon returning to Holland in 1887, he convinced the Dutch government of the need for a medical research laboratory in Batavia (now Djakarta). Eijkman was appointed its first director. With the assistance of Grijns, Eijkman subsequently discovered the involvement of a dietary factor in the development of beriberi.

In 1905 Pekelharing reported his efforts to maintain mice on a diet of purified nutrients. Only with the addition of milk as s dietary supplement was he able to do so; and he thus concluded that milk contains an unknown substance which, even though in very small amounts, in essential to the diet. Without these substances, he stated, the organism lacks the ability to metabolize the major nutrients. Since his reports were published in Dutch, Pekelharing’s findings received little attention. Nevertheless, he became increasingly interested in the new science of nutrition, and in 1908 his monograph on proteins as food appeared. During World War I he focused his attention on problems of mass feeding. He was also instrumental in the founding of the Netherlands Institute of Nutrition.

In 1918 Pekelharing reached retirement age, but he continued studying and writing. An outstanding teacher and scholar, he was active in the Royal Netherlands Association for the Advancement of Medicine, served twice as its president, and was editor of its journal for many years. Pekelharing was in the forefront of the fight against alcoholism. His many honors included membership in the Royal Netherlands Academy of Sciences.

BIBLIOGRAPHY

I. Original Works. A complete bibliography of Pekelharing’s papers and monographs is given in J. M. Baart de la Faille et al., “Leven en werken van Cornelis Adrianus Pekelharing 1848–1922,” in N.V. A. Oostheoek’s Uitgeversnnij (Utrecht, 1948), 211–217. His major works include “Sur le dosage de l’uree,” in Archives neerlandaises ds sciences exactes et naturelles, 10 (1875), 56; “Recherches sur la nature et la cause du beriberi et sur les moyens de la combattre,” in Bailliere et Fils (1888), written with Winkler; “Ueber eine neue bereitungsweise des Pepsins,” in Zeitschrift physiologische Chemie, 22 (1896), 233; “On the Proteins of the Glandular Thymus,” in Proceedings of the Section of Sciences. K. Nederlandse akademie van wetenschappen, 3 (1901), 383; and “Der Eiweiszverbrauch im Tierkorper,” in Zentralblatt fur die gesamte Physiologie und Pthologie des Stoffwechsels, 4 (1909), 289.

II. Secondary Literature. On Pekelharing and his work, see A. M. Erdman, “Cornelis Adrianus Pekelharing,” in Journal of Nutrition, 83 (1964), 1–9; and H. Zwaardemaker, “L’Oeuvre de C. A. Pekelharing jusqu’a son septuagenaire,” in Archives neerlandaises de physiologie de l’homme et des animaux2 (1918), 451–464.

Anne Marie Erdman