Axel Holst
Encyclopedia
Axel Holst was a Norwegian
Norway
Norway , officially the Kingdom of Norway, is a Nordic unitary constitutional monarchy whose territory comprises the western portion of the Scandinavian Peninsula, Jan Mayen, and the Arctic archipelago of Svalbard and Bouvet Island. Norway has a total area of and a population of about 4.9 million...

 professor of hygiene and bacteriology at the University of Oslo
University of Oslo
The University of Oslo , formerly The Royal Frederick University , is the oldest and largest university in Norway, situated in the Norwegian capital of Oslo. The university was founded in 1811 and was modelled after the recently established University of Berlin...

, known for his contributions to beriberi
Beriberi
Beriberi is a nervous system ailment caused by a thiamine deficiency in the diet. Thiamine is involved in the breakdown of energy molecules such as glucose and is also found on the membranes of neurons...

 and scurvy
Scurvy
Scurvy is a disease resulting from a deficiency of vitamin C, which is required for the synthesis of collagen in humans. The chemical name for vitamin C, ascorbic acid, is derived from the Latin name of scurvy, scorbutus, which also provides the adjective scorbutic...

.

Holst gained his medical degree in 1884 and gained his doctors degree in 1892 involving the bacterium streptococcus
Streptococcus
Streptococcus is a genus of spherical Gram-positive bacteria belonging to the phylum Firmicutes and the lactic acid bacteria group. Cellular division occurs along a single axis in these bacteria, and thus they grow in chains or pairs, hence the name — from Greek στρεπτος streptos, meaning...

, both at the Regal Frederiks College. He held his position as professor of hygiene and bacteriology (1893–1921) and held this title, among others until his retirement in 1930.

Along with Dr. Theodor Frølich, a pediatrician, Holst suspected a nutritional deficiency for scurvy in the Norwegian fishing fleet, then called "shipboard beriberi," and thought to be a variant of beri-beri.

Holst and Frølich established an animal model that allowed systematic study of factors that led to the ship-related dietary disease, as well as the preventive value of different substances. Substituting guinea pigs for pigeons (a traditional beriberi research model) as the experimental animal for these studies was a lucky coincidence, as the guinea pig was later shown to be among the very few mammals capable of showing scurvy-like symptoms, while pigeons, as seed-eating birds, were later shown to make their own vitamin C in the liver, and could not develop scurvy.

Scurvy occurred in guinea pigs when a diet was fed consisting of various types of grain, either whole or baked into bread, and these symptoms were prevented when the diet was supplemented with known antiscorbutics like fresh cabbage or lemon juice. Their findings were published in 1907 in the Journal of Hygiene, but was unpopular with the scientific community as the concepts of nutritional deficiencies was unheard of at the time (the concept and word "vitamine" did not arrive until 1912, and was in part based upon Holst and Frølich's work). However, in the later work which led up to the isolation of vitamin C as the antiscorbutic factor in 1932-33, Holst and Frølich's guinea pig model of scurvy proved to be the key biological assay which allowed identification of the chemical substance (hexuronic acid, later called ascorbic acid) which was ascorbutic vitamin.

Throughout his career, Holst made many other contributions, writing out numerous medical books and articles related to sanitation, health and practical hygiene.
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