Chitin and chitosan from mushroom (Agaricus bisporus) using deep eutectic solvents

Area of Science:

• Biochemistry
• Materials Science
• Green Chemistry

Background:

• Chitin, a valuable biopolymer, is abundant in fungal biomass.
• Traditional chitin extraction methods often involve harsh chemicals and multiple steps.
• Deep eutectic solvents (DES) offer a sustainable alternative for biomass processing.

Purpose of the Study:

• To investigate the efficacy of three distinct DES systems for chitin isolation from *Agaricus bisporus*.
• To evaluate the physicochemical properties of the extracted chitin.
• To explore a potential one-step, base-free pathway for chitosan production.

Main Methods:

• Chitin isolation from *Agaricus bisporus* using choline chloride: acetic acid (CCAA), choline chloride:lactic acid (CCLA), and choline chloride:glycerol (CCG) DES.
• Microwave-assisted extraction was employed with the CCAA system.
• Physicochemical characterization using Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), and X-ray photoelectron spectroscopy (XPS).

Main Results:

• All three tested DES systems demonstrated effectiveness in chitin isolation from mushrooms.
• A deproteinization efficiency of 84.25% was achieved.
• Chitin extracted via microwave-assisted CCAA exhibited a degree of deacetylation of 69%.

Conclusions:

• Deep eutectic solvents are viable and efficient media for chitin extraction from mushroom biomass.
• The high deacetylation degree suggests potential for direct chitosan production.
• This study presents a promising, environmentally friendly, one-step method for chitosan precursor isolation.