The mixtures were separately filtered and washed with deionized water to neutral. Crude shiitake chitin with potassium per-manganate (treatment C) to decolorize whereas crab shell chitinwas treated with treatment C. Following decolorization, two kindsof fungal chitin (chitin B and chitin C) and purified crab shell chitin(purified chitin) were washed with deionized water to neutral andfreeze-dried