Bioprocess Optimization of Lobster Waste Treatment Using Lactococcus lactis and Lactobacillus paracasei for N-polysaccharide Extraction

This study focuses on optimizing microbial processes for producing nitrogenous polysaccharides, specifically chitin and chitosan, from crustacean waste using response surface methodology. Lactococcus lactis and Lactobacillus paracasei were employed as microbial strains to assess the effects of key process variables: temperature, time, and substrate concentration, on the degrees of demineralization (DD%) and deproteinization (DP%). The results showed that L. lactis achieved a DD% of 80.61% and a DP% of 41.16%, while L. paracasei demonstrated superior performance with a DD% of 88.87% and a DP% of 55.96%. Fourier-transform infrared (FTIR) spectroscopy confirmed the presence of functional groups characteristic of commercially available chitosan, underscoring the potential of these microbial strains in sustainable chitin/chitosan production. Despite these promising results, the limited proteolytic activities of both strains highlighted the need to incorporate protease-producing microorganisms or adopt a secondary deproteinization step to improve purity. This study emphasizes the potential of green chemistry approaches in enhancing chitin/chitosan extraction, paving the way for sustainable waste management and resource recovery within the seafood industry.