Paddy husk support and rice bran for the production of glucoamylase by Aspergillus niger

Aspergillus niger CFTRI 1105 was cultivated on solid medium for glucoamylase production. Glucoamylase activity obtained was 83.7 U g(-1) DFR (Dry Fermentation Residue) in a medium containing rice bran (100 g), corn flour (2 g), stock mineral solution (10 mL) and tap water (90 mL). When corn flour (2 g) in the medium was substituted with soya flour (2 g) no significant increase in glucoamylase was observed. The effects of soya flour, urea and peptone at the same elemental nitrogen concentration as with corn flour as carbon source on glucoamylase production were investigated. Supplementation with soya hour gave the highest glucoamylase activity (121 U g(-1) DFR) at 72 h and addition of paddy husk to a medium containing corn and soya flour altered the enzyme production from 121 U g(-1) DFR to 71.3 U g(-1) DFR. Addition of gingili oil and coconut oil to the medium caused no improvement in glucoamylase production.