Principles of Biochemistry (2+1)

Preparation of enzyme extract

• Grind a known quantity of sample with a mortar and pestle.
• Homogenise the tissue with twice the volume of ice cold acetone.
• Filter and wash the powder successively with acetone, acetone: ether (1:1) and ether.
• Air dry the powder.
• This acetone powder can be stored in a refrigerator.
• Extract 1 g of powder in 20 ml ice cold water or a suitable buffer.
• Centrifuge at 15,000 rpm for 10 min. and use the supernatant as enzyme extract.