Efficient and green extraction of chitin from Hermetia illucens using deep eutectic solvents and its application for...

Hermetia illucens, with a short growth cycle, is promising as a valuable source of chitin. However, the optimal method for extracting chitin from this insect and its application for hemostasis has not been addressed. This work employed an environmentally friendly choline chloride-lactic acid deep eutectic solvent technology to extract chitin effectively from the Hermetia illucens pupae shells, realizing one-step removal of inorganic salts and proteins. The extraction process was optimized through the response surface methodology, which identified the optimal temperature (92 °C), time (5.6 h), and liquid-solid ratio (20 mL/g) as the conditions that yielded the highest chitin yield (28.40 %) and the highest purity (96.93 %). The structural characterization of the extracted chitin revealed an α-type structure with favorable thermal stability. Furthermore, by regulating the degree of deacetylation, we optimized the degree of protonation of chitin for producing a series of chitosan (Cts), thereby enabling the production of Cts2 with excellent in vitro hemostatic properties. The superior hemostatic performance of Cts2 can be attributed to significantly superior platelet adhesion, achieved preferred adsorption of fibrinogen, and improved blood coagulation. This work provides a theoretical basis for the efficient extraction and high-value application of chitin from Hermetia illucens.