Table 1.
HPLC analysis

HPLC	Gilson 307 piston pump
Column	Alltech IOA-1000 oragnic acids column 7.8×300 mm(I.D.×Length), 9 μm
Detector	Gilson 118 UV/VIS detector
Wave length	210nm
Mobile phase	0.005 N Sulfuric acid
Flow rate	0.3 mL/min
Sample injection volume	100 μL