vagetables (lettuce,curly lettuce , oak-leaf lettuce, frozen spinach) were purchased from a local market. The sample were cut into small pieces of about 1 cm, 1.5g was weight (3 g for frozen spinach),and suspended into 500 ml distilled water. After homogenizing in a Waring Blender for 1 min,the syspension was centrapore ifuged (Eppendort 5810R) at 1700*g for 5 min, and filtered through a 0.45-micromate filter (Durapore HV, millipore