The crude extract of Pyridoxamine (Pyridoxine)-5′-phosphate Oxidase (PNPO) extracted from fresh tea leaves which were grinded by liquid nitrogen with Tris-HCL+ KPO buffer (pH8.5) and fractionated with solid ammonium sulfate, the enzymatic properties were investigated with phenyl hydrazine method. Results showed that when Pyridoxamine phosphate (PMP) as the substrate, the best time for the PNPO oxidation was 30 min, and the optimum pH was 6.5, and the optimum temperature was 50℃. When the value of pH was from 6.0 to 9.0 and temperature was from 10℃ to 40℃, the enzyme was stable. The Kmpmp of the reactive substrate PMP was 2.34 mmol/L under the optimum measure condition.
LI Yan-xia
,
ZHANG Jian-yun
,
HUANG Long-quan
. Analysis on the Activity of PNPO of VB6-metabolizing Enzymes from Tea Leaf[J]. Journal of Tea Science, 2010
, 30(4)
: 273
-276
.
DOI: 10.13305/j.cnki.jts.2010.04.007
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