Julius Wolfgang Weichardt (May 13, 1875 - 1943) was a German bacteriologist who was a native of Altenburg

Altenburg

Altenburg is a town in the German federal state of Thuringia, 45 km south of Leipzig. It is the capital of the Altenburger Land district.-Geography:...

, Thüringen

Thuringia

The Free State of Thuringia is a state of Germany, located in the central part of the country.It has an area of and 2.29 million inhabitants, making it the sixth smallest by area and the fifth smallest by population of Germany's sixteen states....

. In 1900 he received his doctorate at Breslau, where he became an assistant to Carl Flügge

Carl Flügge

Carl Georg Friedrich Wilhelm Flügge was a German bacteriologist and hygienist who was a native of Hannover. He studied medicine in Göttingen, Bonn, Leipzig and Munich, and in 1878 was a lecturer of hygiene in Berlin...

 (1847-1923) at the laboratory for hygiene

Hygiene

Hygiene refers to the set of practices perceived by a community to be associated with the preservation of health and healthy living. While in modern medical sciences there is a set of standards of hygiene recommended for different situations, what is considered hygienic or not can vary between...

 and bacteriology

Bacteriology

Bacteriology is the study of bacteria. This subdivision of microbiology involves the identification, classification, and characterization of bacterial species...

. Afterwards he was an assistant in Dresden

Dresden

Dresden is the capital city of the Free State of Saxony in Germany. It is situated in a valley on the River Elbe, near the Czech border. The Dresden conurbation is part of the Saxon Triangle metropolitan area....

 under pathologist Christian Georg Schmorl

Christian Georg Schmorl

Christian Georg Schmorl was a German pathologist who was a native of Mügeln in the Kingdom of Saxony. He studied medicine in Leipzig and for most of his career he was associated with the city hospital in Dresden....

 (1861-1932), in Paris

Paris

Paris is the capital and largest city in France, situated on the river Seine, in northern France, at the heart of the Île-de-France region...

 at the Pasteur Institute

Pasteur Institute

The Pasteur Institute is a French non-profit private foundation dedicated to the study of biology, micro-organisms, diseases, and vaccines. It is named after Louis Pasteur, who made some of the greatest breakthroughs in modern medicine at the time, including pasteurization and vaccines for anthrax...

 under Ilya Ilyich Mechnikov

Ilya Ilyich Mechnikov

Ilya Ilyich Mechnikov was a Russian biologist, zoologist and protozoologist, best remembered for his pioneering research into the immune system. Mechnikov received the Nobel Prize in Medicine in 1908, shared with Paul Ehrlich, for his work on phagocytosis...

 (1845-1916), in Hamburg

Hamburg

-History:The first historic name for the city was, according to Claudius Ptolemy's reports, Treva.But the city takes its modern name, Hamburg, from the first permanent building on the site, a castle whose construction was ordered by the Emperor Charlemagne in AD 808...

 under American-born hygienist William Philipps Dunbar

William P. Dunbar

William Philipps Dunbar was an American physician, director of the State Hygienic Institute in Hamburg, who made seminal discoveries about cholera control and allergies, including identifying the allergen in grass pollen and cat fur...

 (1863-1922), and at the Berlin

Berlin

Berlin is the capital city of Germany and is one of the 16 states of Germany. With a population of 3.45 million people, Berlin is Germany's largest city. It is the second most populous city proper and the seventh most populous urban area in the European Union...

 institute of hygiene under Max Rubner

Max Rubner

Max Rubner [ru:bner] was a German physiologist and hygienist.He studied at the University of Munich under Adolf von Baeyer and Carl von Voit . Afterwards he taught as a professor at the University of Marburg and the Robert Koch Institute of Hygiene at the University of Berlin...

 (1854-1932).

In 1905 Weichardt was habilitated for hygiene and experimental therapy

Therapy

This is a list of types of therapy .* Adventure therapy* Animal-assisted therapy* Aquatic therapy* Aromatherapy* Art and dementia* Art therapy* Authentic Movement* Behavioral therapy* Bibliotherapy* Buteyko Method* Chemotherapy...

 at the University of Erlangen, where he later became a professor and director of the Bayerische Bakteriologische Untersuchungsanstalt. He made contributions in his research of anaphylaxis

Anaphylaxis

Anaphylaxis is defined as "a serious allergic reaction that is rapid in onset and may cause death". It typically results in a number of symptoms including throat swelling, an itchy rash, and low blood pressure...

, metabolism

Metabolism

Metabolism is the set of chemical reactions that happen in the cells of living organisms to sustain life. These processes allow organisms to grow and reproduce, maintain their structures, and respond to their environments. Metabolism is usually divided into two categories...

 and fatigue. Weickardt postulated that there was a specific "toxin of fatigue", and performed numerous experiments in the early 20th century involving chemical antitoxin

Antitoxin

An antitoxin is an antibody with the ability to neutralize a specific toxin. Antitoxins are produced by certain animals, plants, and bacteria. Although they are most effective in neutralizing toxins, they can kill bacteria and other microorganisms. Antitoxins are made within organisms, but can be...

s to battle fatigue.

• Associated eponym:
• Weichardt's reaction: Test based on the change of surface tension
  Surface tension
  Surface tension is a property of the surface of a liquid that allows it to resist an external force. It is revealed, for example, in floating of some objects on the surface of water, even though they are denser than water, and in the ability of some insects to run on the water surface...
  
   when antigen
  Antigen
  An antigen is a foreign molecule that, when introduced into the body, triggers the production of an antibody by the immune system. The immune system will then kill or neutralize the antigen that is recognized as a foreign and potentially harmful invader. These invaders can be molecules such as...
  
   and antibody
  Antibody
  An antibody, also known as an immunoglobulin, is a large Y-shaped protein used by the immune system to identify and neutralize foreign objects such as bacteria and viruses. The antibody recognizes a unique part of the foreign target, termed an antigen...
  
  react with each other in specific dilutions.