To determine the amino acid content,
the same HPLC system was used on an ODS HYPERSIL (Agilent Tech
Inc., Santa Clara, CA) column and a diode array detector (DAD) at
40
C with a mobile phase of 20% sodium acetate (0.2 M), 40%
acetonitrile, and 40% methanol at a
fl
ow rate of 1.0 ml/min