Redoxon is the name of the first artificially synthesized ascorbic acid (Vitamin C). Redoxon was first marketed to the general public in 1934 – the first mass-manufactured synthetic vitamin in history. It is now a brand owned by German pharmaceutical company Bayer and is sold world-wide.
The product was developed by a team headed by chemist Tadeusz Reichstein, who discovered a method of synthesizing 30-40 g of vitamin C from 100 g of glucose. This used an intermediate step of creating sorbose using an ingenious bacterial fermentation method discovered by a French researcher, Gabriel Bertrand. In this method, fruit flies were attracted to a mixture of wine, vinegar, yeast bouillon, and sorbitol, a substance easily chemically prepared from glucose. Flies which fed upon sorbitol as a major food subtrate excreted bacteria which were able to synthesize sorbose from sorbitol. Using the bacteria, within a few days, it was possible to create 50 grams of sorbose using this method, and it was then easy to synthesise ascorbic acid from this.
Despite concern about using the wild strain of bacteria for fermentation-production of sorbose, the process was superior to a rival method of Szent-Györgyi which isolated Vitamin C from capsicum. After sale of the Reichstein process patent to Hoffmann-La Roche, this process became the basis of the corporation's large-scale production of vitamin C.
The commercial tablets are compounded from ascorbic acid and sodium bicarbonate. When these are added to water, they react to produce sodium ascorbate, water and carbon dioxide, thus producing a pleasant effervescence.
In addition to Redoxon vitamin C, Redoxon Vita Immune tablets are also produced. Each one contains: