Comparative studies on the effect of organic and inorganic nitrogen supplementation of millet and sorghum pomace on the production of three industrial enzymes by <I>Aspergillus niger</I> SL.1

Abstract

Effect of nitrogen source and supplementation of millet and sorghum pomace on the production of cellulase, amylase and laccase by Aspergillus niger SL.1 was investigated using a submerged culture fermentation. The nitrogen sources (ammonium sulphate, yeast extract groundnut cake and neem seed cake) were supplemented at 5 – 20% level in the pomace medium and fermentation was carried out for 72 hours. Supplementation of both millet and sorghum pomace with 10 – 20% groundnut cake and also 5 – 20% neem seed cake in sorghum pomace media significantly (P<0.05) recorded higher level of cellulase production than the control. Amylase production significantly (P<0.05) decreased with increase in the level of supplementation of the pomace with ammonium sulphate and yeast extract. The pomace media containing 10 – 20% supplementation with groundnut cake recorded higher (P<0.05) amylase activity than the control. Sorghum pomace media significantly (P<0.05) induced higher laccase production than that of millet pomace. However, supplementation of millet pomace with ammonium sulphate and groundnut cake significantly (P<0.05) recorded higher laccase production than the control. The study revealed that nitrogen supplementation of the pomace is important and enhanced the production of the three industrial enzymes.

Key Words: Nitrogen source, supplementation, enzyme production

Biokemistri Vol.16(2) 2004: 64-70