# 80: GLYCEROL-SOIL MEDIUM ## Main sol. 80 5 g Peptone 3 g Beef extract 20 g Glycerol 150 ml Soil extract 850 ml Distilled water 15 g Agar 1. Adjust pH to 7.0. Soil extract is prepared by sieving air dried garden soil through a coarse sieve and autoclaving 400 g with 960 ml of distilled water at 121°C for one hour. After the mixture is cool and settled, the supernatant is carefully decanted, filtered through paper, autoclaved in 200 ml quantities, and stored at room temperature until cleared by sedimentation.