The content of TP was calculated by the following
equation:
TPðmg=gÞ ¼ 2A 1:957 ðL1=L2 MÞ;
where L1 is the total volume of extract solution in ml; L2 is
the volume of the extract solution used for analysis in ml;
M is the mass of tea leaves in mg; A is the absorbance at
540 nm; 1.957: constant, meaning that when absorbance
at 540 nm was 0.5 under the earlier conditions, the concentration
of TP was 1.957 mg/ml