Picrorhiza kurroa Royle ex Benth. (Scrophulariaceae), Andrographis paniculata (Burm.f.) Nees (Acanthaceae), Silybum marianum (L.) Gaernt (Sm). (Asteraceae) are well-known plants to treat various ailments. Simultaneous quantification and determination of picroside-I, andrographolide, and silybin were conducted in the combined extract of their respective plants, by reverse-phase high performance liquid chromatography (RP-HPLC). Analytical determination of the proposed HPLC method was validated as per International Conference for Harmonization guidelines. Determination and method validation was carried on RP-HPLC column. Picroside-I, andrographolide, and silybin were quantified as 1.232 ± 0.0102, 0.572 ± 0.0734, 2.037 ± 0.0635 µg/mg, respectively. Validated method for simultaneous estimation of analytes was investigated to be linear, specific, reproducible, and accurate. Recovery of identified analytes was within the specified limit of 99.65%102.59%. The study reveals that the developed HPLC method exhibits potential for determination and quantification of picroside-I, andrographolide, and silybin in in combined extract of P. kurroa, A. paniculata, and S. marianum.
Key words: diterpeniod lactone, flavanolignan, high performance liquid chromatography, Kalmegh, Kutki, Milk Thistle