HPLC and HPTLC densitometric determination of andrographolides and antioxidant potential of Andrographis paniculata

A rapid method based on HPTLC and RP-HPLC with UV detection for quantitative determination of two major bioactive compounds in Andrographis paniculata, andrographolide and 14-deoxy-11, 12-didehydroandrographolide, is described. The recoveries of the two compounds were between 96.5-99.0% by HPTLC method and 98.1-99.2% by HPLC assay. The relative standard deviations of the two compounds ranged between 0.89-0.99 (intra-day) and 0.86-0.98 (inter-day) for the HPTLC method and 0.86-1.02 (intra-day) and 0.87-1.12 (inter-day) for HPLC method. The methods were used for routine analyses and to obtain relative amount of the two compounds in the leaves of the plant cultivated in different locations of Malaysia. The extracts and isolated compounds exhibited lipid peroxidation inhibition and free radical activities.