Quantitative HPLC analysis of phenolic acids, flavonoids and ascorbic acid in four different solvent extracts of two wild edible leaves, Sonchus arvensis and Oenanthe linearis of North-Eastern region in India

A reversed-phase high-performance liquid chromatographic method using photodiode array detector with gradient elution has been developed and validated for the simultaneous estimation of ascorbic acid, free phenolic acids and flavonoids (catechin, rutin, quercetin, myrecetin, apigenin and Kaempferol) in four different solvent extracts of two wild edible leaves of viz. Sonchus arvensis and Oenanthe linearis, collected from North-eastern region in India . The chromatographic separation was carried out on Acclaim C 18 column (5 μm particle size,250 x 4.6 mm), Dionex Ultimate 3000 liquid chromatograph and detection was carried out at three different wave lengths (272, 280 and 310 nm) using a mobile phase of acetonitrile and 1% aqueous acetic acid solution with gradient elution. The experimental results showed high amount of ascorbic acid in S. arvensis and O. Linearis (1.2% and 2.3 % respectively) and gallic acid (0.02% and 0.06% respectively) in 1% aq. acetic acid extract of these two plants. The high percentage of recovery (96-103%), low coefficient of variation ( R2 > 0.99) and low limit of detection (LOD) and limit of quantitation (LOQ) confirm the suitability of the method for simultaneous quantification of ascorbic acid and all phenolic compounds in the two plants under investigation.