Results and discussion
3.1. Standardization of the formulation and its individual
ingredients through RP-HPLC
The quantitative analysis was performed by RP-HPLC under
the isocratic conditions using the external standard technique.
The separation was performed with the mobile phase consisting
of methanol, water and acetic acid in the ratio of 76:23:1
(v/v). Linearity of the calibration curves was tested by linear
regression analysis and found to be linear in the concentration
range 10–100g/ml with good correlation between concentration
and peak area with a correlation coefficient (r2) of more
than 0.99. The peak of GA was identified by comparing retention
time of reference GA, extracts and formulations in the same chromatographic
conditions. The amount of GA present in individual
ingredients and Triphala formulation was estimated to be about
7.57±2.33 mg/g (EO), 3.20±0.86 mg/g (TB), 3.20±1.24 mg/g (TC)
and 4.30±2.09 mg/g (TL) (Table 1). Fig. 1(A and B) represents the
HPLC chromatogram of standard gallic acid and Triphala formulation.
The presence of gallic acid in the TL was confirmed by the
retention time of 4.0 min.