Table 2. Comparisons of the yield and purity of Na-GST-1 at each step of the original and optimized purification process.

Step	Process	Purity (%)	Recovery Yield (%)
QXL	Goud 2012	79	86
	Original	81	83
	Optimized	91	75*
Butyl	Goud 2012	94	64
	Original	95	71
	Optimized	>96	84*
SEC	Goud 2012	98	94
	Original	99	98**
	Optimized	>98	94*

A “*” indicates that the calculation is based on SDS-PAGE and “**” indicates value is based on A280 measurement.