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E. Carry out the test as described in the “Thin-layer Chromatography” (Appendix 3.1), using silica gel GF254 as the coating substance and a mixture of 5 volumes of toluene, 4 volumes of ethyl formate and 1 volume of formic acid as the mobile phase but allowing the solvent fron to ascend 10 cm above the line of application. Apply separately to the plate, 20 µl solution (A) and 1 ml of solution (B). Prepare solution (A) by refluxing 500 mg of the sample, in powder, with 10 ml of ethanol for 10 minutes, filter.To the filtrate, add 500 mg of decolorizing charconal, reflux for a few minutes, filter, wash the filter paper and the funnel with small amount of ethanol. After removal of the plate, allow it to dry in air and examine under ultraviolet light (254 nm), marking the quenching spots. The chromatogram obtained from solution (A) showa a quenching spot (hRf value 43 to 44), corresponding to the gallic acid spot from solution (B), and one spot of lower hRf value. Spray the plate with iron(III) chloride TS; the spot due to gallic acid is blue-black and the other blue-black spot is observed (Table 1); see also Fig 3.