Abstract:The extraction of polysaccharide and triterpenoids from the stipes （processing residues） of Ganoderma tsugae Murr was explored. Furthermore， the antitumor and antioxidant activities of the extracted polysaccharide and triterpenoids were determined. The ultrasound-assisted enzymatic method was used for extraction. The 3-（4，5-dimethyl-2-thiazolyl）-2，5-diphenyl-2H-tetrazolium bromide（MTT） method was employed to study the inhibitory effects of the extracted triterpenoids and polysaccharide on two cancer cell lines （HepG2 and Caki-1）. The polysaccharide was characterized by infrared spectroscopy（IR）. Furthermore， the antioxidant activities of triterpenoids and polysaccharide in vitro were determined. The results showed that the optimal extraction conditions were ethanol concentration of 40%， ultrasonic time of 30 min， ultrasonic temperature of 50 ℃， solid-liquid ratio of 1∶25 （g/mL）， enzyme dosage of 500 U/g. Under these conditions， the yields of polysaccharide and triterpenoids were （1.570±0.026）% and （1.635±0.020）%， respectively. The concentration of polysaccharide and triterpenoids was proportional to the inhibition rate on HepG2 cells. At the concentration of 1 000 μg/mL， polysaccharide showed the inhibition rates of （81.73±2.20）% and （71.39±2.73）% on HepG2 and Caki-1 cells， respectively. At the concentration of 500 μg/mL， triterpenoids demonstrated the inhibition rates of （64.33±1.16）% and （76.95±2.20）% on HepG2 and Caki-1 cells， respectively. The IR showed that polysaccharide was β-pyranose. Both the extracted polysaccharide and triterpenoids showcased strong antioxidant activities in vitro.