Ds. Rao et T. Panda, CRITICAL ANALYSIS OF THE EFFECT OF METAL-IONS ON GLUCONIC ACID PRODUCTION BY ASPERGILLUS-NIGER USING A TREATED INDIAN CANE MOLASSES, Bioprocess engineering, 10(2), 1994, pp. 99-107
Gluconic acid fermentation by Aspergillus niger has been investigated
using untreated and treated Indian cane molasses. The yield of gluconi
c acid was found to be reduced using an untreated molasses medium comp
ared to a defined medium. Hence, molasses was subjected to various pre
treatment techniques. Pretreatment reduced the levels of various catio
ns and anions. As the synthesis of gluconic acid has been observed to
be influenced more by cations than anions, the effect of various metal
ions, viz., copper, iron, zinc, manganese, calcium, and magnesium on
the yield of gluconic acid has been critically examined in both untrea
ted and treated cane molasses. These results have been compared with a
defined medium. The yield of gluconic acid was influenced more by a c
ombination of metal ions rather than individual ions. Potassium ferroc
yanide treatment gave the most promising results compared to other tre
atment techniques.