Abstract: The conditions of enzymatic pretreatment of shell of Eucommia ulmoides Oliv. were investigated, using the amount of total sugars from enzymatic hydrolysate of shell of E.ulmoides with anthrone colorimetry and extraction yield of E.ulmoides gum as assessing index. The optimum enzymatic pretreatment conditions were:temperature 50℃, pH value 3.8,cellulase dose 0.3g, solid-liquid ratio 1:15(g:mL), extracting twice and 3h each time. E.ulmoides gum was extracted from raw materials pretreated. The gum yield of the first extraction from the pretreated shell was57.7%, which was 1.3 times of that from shells without pretreatment. The results of TLC determination showed that the composition of E.ulmoides gum extracted from pretreated shell is basically similar to that from non-pretreated shell.

Key words: cellulase, shell of Eucommia ulmoides Oliv., anthrone colorimetry, E.ulmoides gum