Polysaccharides isolated from artificially cultivated mushroom in Malaysia. The extracted polysaccharides have been thoroughly characterized. Antioxidant activity of extracted polysaccharides has been checked. The efficiency of ultrasonic extraction was compared with conventional methods. Ultrasonic conditions provide better environment for isolating bioactive compounds. Ultrasonic cavitation influenced the extraction of (1-3; 1-6)-β-d-glucans.