Immobilization of Providencia stuartii Cells in Pumice Stone and Its Application for N-Acetylglucosamine Production
1Food Technology Department, Universitas Pelita Harapan, Jl. M.H. Thamrin Boulevard, Lippo Karawaci, Tangerang 15811, Indonesia
2Faculty of Fisheries and Marine Sciences, Brawijaya University, Jl. Veteran No. 1, Malang 65113, Indonesia
Received: 1 October 2020
Accepted: 12 November 2021
cell immobilization; chitin degradation; N-acetylglucosamine production; Providencia stuartii; pumice stone; repeated fermentation
Research background. Shrimp shells contain chitin that can be further processed into N-acetylglucosamine, which has been extensively used to treat joint damage. Providencia stuartii has a strong chitinolytic activity and may be utilized in the form of immobilized cells in repeated fermentation. Pumice is a porous and rigid stone that offers superior mechanical strength, making it suitable for immobilization.
Experimental approach. In the research submerged fermentation with different pumice stone sizes and pumice stone/growth medium ratios (m/V) was carried out for 4 days at 37 °C and pH=7.0. The optimum pumice stone size and pumice stone/growth medium ratio (m/V) were used to determine the optimum fermentation cycle for the production of N-acetylglucosamine using immobilized P. stuartii.
Results and conclusions. Pumice stones of 1.0 cm×1.0 cm×1.0 cm and pumice stone/growth medium ratio of 1:5 were found to be the optimum conditions for successful immobilization of (90.0±1.6) % cells and production of (331.4±7.3) g/L N-acetylglucosamine. The highest N-acetylglucosamine concentration of (323.0±2.5) g/L was obtained in the first fermentation cycle, which then decreased and remained stable throughout the last three cycles.
Novelty and scientific contribution. P. stuartii, a strong chitinolytic bacterium previously isolated from rotten shrimp shells, was used for the first time in immobilized form to produce N-acetylglucosamine. The findings in this research showed the potential use of P. stuartii cells immobilized in pumice stone for continuous production of N-acetylglucosamine in repeated fermentation.