Utilization of Palm Kernel Cake as a Novel Substrate for Phytase Production by Aspergillus niger USM AI1

Abstract

The present study was carried out to optimize the cultural conditions of phytase production by Aspergillus niger USM AI1 using palm kernel cake (PKC) as the substrate in a solid state fermentation (SSF) system. The optimized cultural conditions of 10 g of PKC with a particle size of ≤0.5 mm, an inoculum size of 1x105 spores/ mL, moisture content of 60% (v/w), and a mixing frequency of once every 48 hours produced 4.91±0.17 U/g dried substrate of phytase and 1.14±0.04 mg glucosamine/ g dried substrate of fungal growth. Maximum growth as well as enzyme production was recorded on the 4th day of cultivation at room temperature (30±2 ºC). The findings indicated that phytase production increased 171.3% after optimization (4.91±0.17 U/g dried substrate) compared to before optimization (1.81±0.16 U/g dried substrate). This study showed that PKC is a potential medium for phytase production in SSF.