Simultaneous fermentation and hydrolysis to extract chitin from crayfish shell waste.

Area of Science:

• Biotechnology
• Bioprocess Engineering
• Sustainable Chemistry

Background:

• Chitin, a valuable biopolymer, is abundant in shellfish waste but extraction methods are often inefficient or environmentally harmful.
• Developing sustainable and cost-effective chitin extraction processes is crucial for utilizing this abundant bioresource.
• Current methods for chitin extraction face challenges in terms of environmental impact and economic feasibility.

Purpose of the Study:

• To develop an efficient, environmentally friendly, and economically feasible method for chitin extraction from crayfish shell waste powder (CSP).
• To utilize Bacillus coagulans LA204 and proteinase K for simultaneous enzymatic hydrolysis and fermentation to remove calcium and proteins.
• To optimize chitin extraction conditions using a bioreactor under non-sterile conditions.

Main Methods:

• Simultaneous enzymatic hydrolysis and fermentation of CSP using Bacillus coagulans LA204 and proteinase K.
• Process conducted in a 5-L bioreactor at 50°C with 5% (w/v) CSP, 5% (w/v) glucose, and 10% microbial inoculation.
• Non-sterile conditions were employed for the 48-hour fermentation period.

Main Results:

• Achieved high deproteinization efficiency of 93% and demineralization efficiency of 91%.
• Obtained a chitin recovery rate of 94% from the crayfish shell waste.
• Demonstrated that 1 mol of additional glucose effectively removed 0.91 mol of calcium carbonate, and 93% of removed protein was hydrolyzed.

Conclusions:

• Simultaneous enzymatic hydrolysis and fermentation is a novel and competitive biological strategy for chitin extraction.
• This method offers an efficient and sustainable approach to valorize shellfish waste.
• The process holds potential for industrial application in chitin production.