Qualitative and quantitative analysis of biologically active principles ...

The presence of baicalein in Scutellaria colebrookiana and S.
violacea detected by medium pressure liquid chromatography was
confirmed by HPLC.
For the confirmation of baicalein, the chloroform and acetone
extracts of Scutellaria were analysed with HPLC (Shimadzu, Japan).
The separation was performed using reverse–phase C18 column at
25 o C with a flow rate of 1 ml/min of the solvent acetonitrite. The
absorbance for the baicalein was monitored at 274 nm with a UV
detector SPD­10A and CLASS VP software. The retention time of
standard baicalein (Sigma) was 3.3 min (Figure 10 A). Peaks in the
same retention time (3.3 min) were also detected in chloroform as
well as acetone extracts of both species of Scutellaria. The
concentration of baicalein in the extracts was also calculated using
standard. In Scutellaria colebrookiana, the concentration of
baicalein was 0.229 and 0.210 mg/g dry weight (root) in acetone
and chloroform extracts, respectively (Figure 10 B and 10 C). The
concentration was 0.134 and 0.150 mg/g dry weight (root) in
acetone and chloroform extracts, respectively in S. violacea (Figure
10 D and 10 E).
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