Optimal conditions for oxalic acid production by Aspergillus niger and A. flavus

Wisam Naji Atiyah AL-MEHANA, Majid Kadhim AL-SHIBLY, Farqad Hasan Falih AL-DAEMI


The cultural optimum conditions for oxalic acid production from two fungi isolates viz. Aspergillus niger and A. flavus were studied by, including carbon, nitrogen source, salts and pH. The results showed that the molasses can be used as a carbon source of the acid production and its best concentration was 5.6 for both isolates, while the best nitrogen source was the ammonium sulphate with production of 24.1 and 21.3g/l for both fungi, respectively. Based on the results, KH2PO4 0.1+MgSO4.7H2O 0.05% was the best compound for production. pH value with higher mount of acid production was 6.5.


Oxalic acid, Molasses, PH, Nitrogen source.

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