An improved method for extracting and activity determining of myrosinase

An improved method of extraction and activity determination for the myrosinase were investigated and the best method was proposed as follows:150 mg sample of tissue was solubilized in 1 mL of extraction buffer.The sample was centrifuged then the supernatant was collected and used as myrosinase extract.3 mL reaction mixture which contains 0.2 mmol/L sinigrin was allowed to equilibrate at 37℃ then the reaction was initiated by adding 150 μL enzyme extract to the 1cm cuvette.Decline in optical density as a result of sinigrin breakdown was plotted at 227 nm for 5 min after a 3 min pre-reaction period using a spectrophotometer.The improved method was performed by using less plant sample quantity and easy to operate,which is suitable for parallel determination of many samples.