Critical analysis of the effect of metal ions on gluconic acid production by Aspergillus niger using a treated Indian cane molasses
✍ Scribed by D. Subba Rao; T. Panda
- Publisher
- Springer
- Year
- 1994
- Tongue
- English
- Weight
- 703 KB
- Volume
- 10
- Category
- Article
- ISSN
- 1615-7605
No coin nor oath required. For personal study only.
✦ Synopsis
Gluconic acid fermentation by Aspergillus niger has been investigated using untreated and treated Indian cane molasses. The yield of gluconic acid was found to be reduced using an untreated molasses medium compared to a defined medium. Hence, molasses was subjected to various pretreatment techniques. Pretreatment reduced the levels of various cations 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 untreated and treated cane molasses. These results have been compared with a defined medium. The yield of gluconic acid was influenced more by a combination of metal ions rather than individual ions. Potassium ferrocyanide treatment gave the most promising results compared to other treatment techniques.
2.2 Culture maintenance
The organism was maintained on potato-dextrose-agar medium having kg/m3: Glucose -25, potato -200 and agar -20. The culture was grown at 30 ~ and the slants were preserved at 4 ~
2.3 Germination medium
To develop the inoculum, the following germination medium was used (in kg/m3): Glucose -30, (NH4)zHPO~ -4.2, urea -1.1, KH2PO4 -2.0 and MgSO4.7H20 -1.7. The pH was adjusted to 6.5 with 5 M NaOH before inoculation.