Biological importance of gluconic acid
Answers
Gluconic acid occurs naturally in fruit, honey, and wine. In 1929 Horace Terhune Herrick developed a process for producing the salt by fermentation. As a food additive (E574), it is now known as an acidity regulator. The gluconate anion chelates Ca² +, Fe² + , Al³ + , and other metals, including lanthanides and actinides.
Answer:
Gluconic acid
Gluconic acid (2,3,4,5,6-pentahydroxy caproic acid, C6H12O7) (Figure 6) is a noncorrosive, nontoxic, mild organic acid with a brown clear appearance. It is very soluble in water and has a mild and refreshing taste. It is a good chelator at high pH, with better activity than commonly used chelators.
Gluconic acid was discovered in 1870 by Hlasiwetz and Habermann, when glucose was oxidized with chlorine. In 1922 it was isolated from a strain of A. niger. Later, other filamentous fungi, such as Penicillium, Scopulariopsis, Gonatobotrys, and Gliocladium, and also oxidative bacteria, such as strains of Pseudomonas, Gluconobacter (Acetobacter), Moraxella, Micrococcus, Enterobacter, and Zymomonas were found to produce gluconic acid. Already in the 1940s it was possible to obtain good yields of gluconic acid using A. niger by fermentation, neutralizing the accumulating acid with calcium carbonate.
The physiological functions of gluconic acid accumulation for these organisms are not clear; one possibility is its contribution to the competitiveness of the organism, removing glucose from the close environment. In the case of P. expansum (a phytopathogenic fungus), it was demonstrated that secreted gluconic acid contributed to the colonization and disease development of apple tissues by this fungus.