Isolation, Characterization, and Simultaneous Quantification of Main Chemical Constituents from Cassia Alata Linn. Leaves

The leaves of Cassia alata L. are used in traditional Vietnamese medicine to treat ringworm and fungal skin infection. This study aimed to isolate marker compounds from the crude methanol extract of C. alata leaves and develop a validated method to control these compounds using HPLC-DAD. The three isolated compounds were identified as rhein (1), aloe-emodin (2), and kaempferol (3) by NMR and HR-ESI-MS. A quick, precise, and accurate HPLC-DAD method in 20 min of analysis time to quantify isolated maker compounds of Cassia alata was developed for the first time. The analysis was performed on a Hypersil GOLD C18 column (150 x 2.1 mm, 3 µm) with 0.1% formic acid in water-methanol gradient elution. The linearity, specificity, sensitivity, precision, and accuracy parameters were validated. The accuracies of the method were 99.0 – 103.5% and linearity (r2 > 0.9995) were achieved. The LODs and LOQs were less than 0.74 µg/mL and 2.25 µg/mL. The developed HPLC method could be applied for quality control testing of C. alata leaves. Keywords: Cassia alata L., kaempferol, rhein, aloe-emodin, HPLC-DAD.