The fresh spinach leaves were washed, chopped into small
pieces, and homogenized with a Waring 2-speed commercial blender
(Waring Commercial, Torrington, CT) for 1 min at the highest
speed 22,000 rpm. The ratio between the spinach leaves to water
was 1:4. This pulp was used to study the formation of Zn–chlorophyll
derivatives and their extraction either by enzyme-assisted
or solvent alone.