Abstract: Under the optimized conditions for the enzyme extraction and activity analysis, chlorophyllase was purified and its characterization was studied. The results indicated that the amount of polivinpolypyrrolidone (PVP) had great impact on chlase activity, chlase activity increased to max as pH value rose to 7.5. It was found that the enzyme reaction was stable at 45℃ in 15 min. Using the methods of ammonium sulfate precipitation and column chromatography on Sephadex G-200, Sepharose CL-6B, chlase in the tea leaves was purified. After three steps of Isolation and purification, It was purified 55.96 fold and a yield of 9.45%. there are one chlase stripe by SDS-PAGE. The subunit molecular mass was 37.2 kD. Research on the characterization of the purified chlase proved that the enzyme showed optimal activity at pH 7.5 and 45℃. The survival rate of enzyme activity remained 45% when stored 4℃ for a month. Adding metal ions Ca²⁺、Mg²⁺、Zn²⁺、Fe³⁺ and EDTA into chlase solution could show the promoting role on the activity of chlorophyllase in certain degree.

Key words: tea plant, chlorophyllase, characterization, extraction, isolation and purification