University of Tartu, Ülikooli 18, 50090 Tartu, Estonia
In 1874 Gustav von Bunge received his degree in chemistry at the University of Dorpat (now the University of Tartu).
Leipzig University, Augustusplatz 10, 04109 Leipzig, Germany
In 1882 Gustav von Bunge received the degree of Doctor of Medicine at the University of Leipzig.
At the University of Dorpat (now the University of Tartu), the biochemist Carl Schmidt became both teacher and promoter of Bunge as a student of chemistry and employed him as an assistant in his laboratory from 1872 onward. Schmidt inspired him, above all else, to tackle the problem of mineral (inorganic) metabolism, and as early as 1874, the year in which he received his doctorate and became an associate professor of physiology, the first significant results of his experiments in that area appeared.
In 1882 Bunge received the degree of Doctor of Medicine at the University of Leipzig.
In 1885 Gustav von Bunge answered an invitation from the University of Basel, became extraordinary professor of medicine there, and then in 1886, an ordinary professor of physiological chemistry. His most famous student was the physiologist Emil Abderhalden.
Bunge showed himself to be a first-rate nutritional scientist, especially in recognizing the significance of mineral salts in the diet of men and other mammals, together with all of its consequences. One of his very first studies on this subject created quite a stir. It dealt with the role of salt (sodium chloride) in nourishment and concluded that herbivores absorb large excesses of potassium in their diet. This led to an increased salt elimination, and thereby to considerable salt losses to the organism and to a correspondingly increased salt requirement. It was typical of Bunge not to remain content after discovering certain physiological facts, and be immediately set about to figure out their ethnological, social, and sociological significance. He found that hunting and nomadic peoples who lived exclusively on meat did not require salt, and actually detested it, whereas vegetarians could not exist without adding salt to their diet. Therefore, the discovery and utilization of salt must have played a very important role in man’s transition from a nomad into a settled agricultural worker.
An important point that Bunge brought up in his studies on the role of salt in man’s diet was of a phylogenetic nature: The high salt content of vertebrates attests to their descent from inhabitants of the sea. Since ontogenesis repeats phylogenesis, then the salt content of a vertebrate should be greater the younger the vertebrate is; this was precisely what Bunge was able to demonstrate when he determined the salt content in the cartilage of cattle embryos in the various stages of their development and in that of calves of various ages.
Another area in which Bunge did research was the quantitative analysis of mineral substances in nutrients and the related question of the necessity of a constant supply of salt for the full-grown organism. In connection with the question of the quantitative and qualitative mineral requirement of growing and fully grown organisms, there are the analyses of ash constituents in the milk of humans and various other animal species, undertaken first by Bunge in Dorpat and then in Basel by his student Abderhalden. Great differences were found above all in lime content. This phenomenon was explained by the fact that the lime content of the milk and the growth rate of the animal in question were in each case positively correlated.
Proceeding from the importance of lime supply in the development of the organism., two works appeared between 1901 and 1904 concerning "increased sugar consumption and its dangers". Limitation of the supply of calcareous nutrients (calcareous fruits)in favor of consumption of chemically pure sugar was viewed as the reason for arrested skeletal development and for the frequent appearance of tooth decay.
One of the main problems posed in Bunge’s studies had to do with iron metabolism. The crux of his study on this subject was his search for the ferriferous precursors of red blood pigment in food. According to the theory of the inability of animal cells to synthesize complicated organic compounds, prevalent at that time, it was unthinkable that inorganic iron found in food and resorbed from it might be utilized to synthesize hemoglobin in the organism. Accordingly, Bunge attempted to isolate an organic iron complex out of egg yolk. In Basel. Bunge’s students Häusermann and Abderhalden conducted feeding experiments or iron salt supplement to an iron-poor diet. The results of these experiments seemed to confirm Bunge’s thesis: only organically bound iron can be resorbed and utilized for the building up of hemoglobin. Iron-rich vegetables similarly have a favorable influence on laboratory-produced anemia, which meant to Bunge that even in these nutrients, iron is found organically bound.
A prerequisite for conducting such studies on iron metabolism was the control of a perfectly functioning method of quantitative iron determination. With the help of this method, Jaquet and Bunge, in 1889, succeeded in determining the iron content of blood pigment exactly and thereby establishing a firm basis for the elucidation of the constitution of the hemoglobin molecule.
Although nutritional physiology formed the center of Bunge’s research activities, there is another area of his work that should not be overlooked. This is the study he pursued with Schmiedeberg on the synthesis of hippuric acid from benzoic acid and glycine in the animal organism (1876). This important not only because it recognized the kidneys as the site of synthesis, but also because the methods he applied to investigation of metabolic problems are still used universally.
Gustav von Bunge was the author of treatises on alcoholic spirits, of which he denounced as a "threat to health and heredity". It is therefore not astonishing that he became a champion of the abstinence movement and a great enthusiast of the prohibition laws in the United States.
Gustav von Bunge was a member of the Academy of Sciences Leopoldina.