Fanny Angelina Hesse

Fanny Angelina Hesse, around 1883

Fanny Angelina Hesse , b. Eilshemius, (born June 22, 1850 in New York , † December 1, 1934 in Dresden ) was the inventor of the pioneering use of agar-agar as a gelling agent for bacterial culture media.

Life

Fanny Angelina Hesse was born in New York in 1850 . Her father Henry (Hinrich) Gottfried Eilshemius emigrated from Germany to the USA in 1842, her mother Cecile Elise was a daughter of the Swiss painter Leopold Robert . In 1872 Fanny Angelina Eilshemius toured Europe with her family. In Dresden she met the young doctor Walther Hesse , who was then an assistant doctor in the nearby town of Pirna and whom she had already met in the USA. She attended a “posh girls' boarding school” in Switzerland. On May 16, 1874, she married Walther Hesse in Geneva . The couple then lived in Zittau , where Walther Hesse practiced as a doctor, and then for more than 10 years in Schwarzenberg / Erzgeb. From 1877 Walther Hesse was a district doctor there and carried out bacteriological research. In 1890 the Hesses moved to Dresden-Strehlen because Walther Hesse became a district doctor in Dresden . Walther Hesse died in 1911. In 1934 Fanny Angelina Hesse died. Despite her outstanding invention, she remained largely unknown.

Angelina and Walther Hesse had three sons, including Friedrich Henry (1875–1960, chief physician of the Dresden- Blasewitz forest sanatorium ) and Gustav (1876–1945, director of the Jena University Dental Clinic).

Agar-agar as a gelling agent for bacterial culture media

backgrounds

In the early days of bacteriology , liquids such as meat broth were used as bacterial culture media. The problem with liquid cultures is that different bacteria are closely mixed together and are difficult to separate. Thus, it is difficult to produce pure cultures of bacteria. Therefore, they looked for solid culture media and used potatoes, coagulated egg white, starch pulp and meat. When properly inoculated, bacteria grow on it in separate colonies, but it is difficult to reliably distribute the bacteria in such a way that colonies arise from individual bacterial individuals. It is also difficult to microscope and see colorless bacterial cultures on them. Robert Koch was researching a better medium and he experimented with gelatine gels, which he mixed with various substances. At that time, gelatine was already being used in mycology as a culture medium or as a gelling agent for culture media. Gelatine, however, has two major disadvantages: on the one hand, it is broken down by certain bacteria and thus liquefied, and on the other hand, it melts at the incubation temperature of 37 ° C, which is required for many bacteria that are pathogenic to humans. The discovery of agar-agar as a temperature-stable gelling agent for culture media avoided both of these problems, and this made many further discoveries in bacteriology possible. Agar-agar is still used in bacteriology today.

Circumstances of Discovery

In the winter of 1881–82, Walther Hesse became Robert Koch's research assistant at the Imperial Health Department in Berlin, where he dealt with the then new science of bacteriology. He researched the bacteria content in the air. After half a year in Berlin, he returned to Schwarzenberg, where he continued his research in his own small laboratory at home. His wife Fanny Angelina Hesse, known as Lina, worked in this laboratory as a laboratory assistant and draftsman. Walther Hesse used gelatine with all its disadvantages as a culture medium for his studies. In the hot summer of 1881, Fanny Angelina Hesse suggested using agar-agar to gel the culture media. She had received from her mother a recipe for fruit jelly and vegetable jelly with agar-agar, which she in turn had received from Dutch friends who had lived on Java . Agar-agar was ideal for culture media. Walther Hesse immediately informed Robert Koch of the discovery of his wife. With agar, Koch succeeded in discovering the tubercle bacillus . Robert Koch informed the public on March 24, 1882 in a lecture about the isolation of the tuberculosis pathogen . He also mentioned the use of agar for culture media for the first time, but not the merits of Ms. Hesse.

literature

• Wolfgang Hesse: Walther and Angelina Hesse - Early Contributors to Bacteriology. (Translated from German into English by Dieter HM Gröschel) In: ASM News. Volume 58, No. 8, 1992, pp. 425-428. PDF (Wolfgang Hesse is the grandson of Fanny Angelina and Walther Hesse.)
• Arthur Parker Hitchens, Morris C. Leikind: The Introduction of Agar-Agar into Bacteriology . In: Journal of Bacteriology. Volume 37, No. 5, 1939, pp. 485-493. PMID 16560221 PDF

Individual evidence

1. ↑ Georg Räschemeyer Mrs. Hesse's secret recipe in mare no. 140, June / July 2020, p. 84 ff