MJAS

Manuscript Details

Optimization of Solid-State Fermentation Parameters to Enhance Phytase Production by Aspergillus niger Using Palm Kernel Expeller

Ain Nazira, N. E.¹, Mohd Noor Hisham, M. N.1^*, Nasyatul Ekma, M. H.², Shamarina, S.¹ and Noraini, S.²

¹Department of Biology, Faculty of Science, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia
² Livestock Science Research Centre, MARDI Headquarters, 43400 Serdang, Selangor, Malaysia

Malaysian J. Anim. Sci. 2025 28(1): 106-119

Click to view the abstract

The production of microbial phytase through solid-state fermentation (SSF) offers a sustainable alternative to conventional enzyme production systems. This study aimed to optimize key SSF parameters using the one-factor-at-a-time (OFAT) approach to enhance phytase activity by Aspergillus niger cultivated on palm kernel expeller (PKE), a nutrientrich agro-industrial by-product. Although initial screening included A. oryzae and Rhizopus oligosporus, only A. niger demonstrated the highest phytase activity of 269.67 ± 13.52 FTU/mL under non-optimized conditions and was selected for further optimization. Three critical SSF parameters: incubation temperature (28°C–50°C), moisture content (30%–60% v/w), and inoculum size (1%–15% v/w) were individually evaluated. Maximum phytase activity (299.42 ± 6.64 FTU/mL) was achieved at 28°C, 40% moisture, and 1% inoculum size. Under these optimized conditions, phytase production improved by 23% compared to the unoptimized set-up (116.92 ± 7.57 FTU/mL), confirming the significant influence of physical parameters on fungal enzyme biosynthesis. These findings support the valorization of PKE for local phytase production, contributing to improved phosphorus bioavailability in poultry diets while reducing reliance on imported feed additives. The results provide a foundation for further scaleup studies aligned with Malaysia’s circular bioeconomy goals and Sustainable Development Goals (SDGs) 2 and 12.