RAPID DENSITOMETRIC METHOD FOR QUANTIFICATION OF GALLIC ACID AND COUMARIN IN THE LEAF OF MEDICINAL PLANT POUZOLZIA BENNETTIANA FROM THE NILGIRI HILLS USING HPTLC

Abstract

The primary aim of the study is to identify and quantify the amount of gallic acid and coumarin present in the methanolic leaf extract of Pouzolzia bennettiana by HPTLC technique. The plant extract was collected using Soxhlet apparatus. Standard gallic acid and coumarin were prepared separately in 1 mg/ml concentration. The methanolic leaf extract was prepared as 100 mgmL^-1 concentration. The standard and sample were loaded on a 10 x 10 Silica gel 60F254 with 250 µm TLC plate using Hamilton syringe and CAMAG LINOMAT 5 instrument. It was developed with respective mobile phase Toluene: Ethyl Acetate: Formic acid: Methanol in the ratio of 3:6:1.6:0.4 v/v/v/v up to 80 mm. It was later scanned at 500 nm. The developed method was robust. The amount of gallic acid and coumarin were found to be 0.43 (%W/W) and 0.36 (%W/W) respectively. The LOD was 1.75062307 µg/spot for gallic acid and 1.650265 µg/spot for coumarin. The LOQ was found to be 5.30491838 µg/spot for gallic acid and 5.000802 µg/spot for coumarin. The several constituents present in the extract did not interfere with the peak of gallic acid and coumarin proved the specificity. The compounds gallic acid a part of tannin a phenolic acid and coumarin a hydroxyl cinnamic acid group has several uses. The developed HPTLC method was rapid, accurate, precise, reproducible and specific for the simultaneous estimation of gallic acid and coumarin. This can be applied in routine quality control and analysis of plants and herbal medicines.