Catechins are of polyphenol group contained in green tea that give bitter taste. They have various physiological functions are reported such as inhibitory for high blood pressure, control of blood cholesterol, control of blood-sugar level, antioxidative, anti-aging, anti-bacterial and anti-allergic activities. Main constituents of Catechins in Green tea are epicatechin, epigallocatechin, epicatechin gallate, and epigallocatechin gallate.

In this report, catechins in green tea were measured and analyzed by Ultra High-performance Liquid Chromatography (UHPLC) with photodiode array detection, which has a high-speed data acquisition rate at 100 spectra/sec.