Isolation of Chitin from the Shell of the Blue Crab (Portunus pelagicus) and a Review of Its Potential as a Cholesterol - Lowering Agent

The swimming crab (Portunus pelagicus) is a fishery commodity that produces large amounts of shell waste and has the potential to be used as a source of chitin. This study aims to isolate chitin from swimming crab shells through demineralization and deproteinization processes and then characterize it using FTIR, accompanied by a literature review regarding the potential of chitin as a cholesterol-lowering agent. The demineralization stage produced a yield of 35.07%, while the yield of chitin after deproteination reached 87.10%. FTIR analysis showed typical chitin absorption bands, namely N–H stretching (3255 cm⁻¹), Amide I (1621 cm⁻¹), Amide II (1552 cm⁻¹), C–O–C asymmetric stretching (1154 cm⁻¹), and β-(1→4) glycosidic bonds (872.8 cm⁻¹), which confirmed the formation of the chitin structure. Based on a literature review, chitin and chitosan have the potential to lower cholesterol levels through bile acid binding and reduced lipid absorption. Therefore, chitin from crab shell waste is suitable for development as a raw material for bioactive chitosan, although further biological testing is needed