Development and Validation of an HPLC-PDA Method for Quantitation of Ten Marker Compounds from Eclipta prostrata (L.) and Evaluation of Their Protein Tyrosine Phosphatase 1B, α-Glucosidase, and Acetylcholinesterase Inhibitory Activities

The aerial parts of Eclipta prostrata is used as a traditional medicine and vegetable. In traditional folk medicine, it is used for treatment of hemorrhages, hepatic, disease, renal injuries, hair loss, tooth mobility, and viper bites. In this study, ten compounds (1 ‒ 10) were isolated from the aerial parts of E. prostrata. A reliable high performance liquid chromatography equipped with photometric diode array detector (HPLC-PDA) method was developed to simultaneously quantitate 10 marker compounds [chlorogenic acid (1), paratensein 7-O-β-ᴅ-glucoside (2), quercetin 7-O-β-ᴅ-glucoside (3), luteolin 7-O-β-ᴅ-glucoside (4), apigenin 7-O-β-ᴅ-glucoside (5), apigenin 4"-O-β-ᴅ-glucoside (6), apigenin (7), luteolin (8), wedelolactone (9), and paratensein (10)]. In addition, compounds 5 and 6 showed considerable inhibitory effects against protein-tyrosine phosphatase 1B (PTP1B) enzyme. Moreover, compounds 6 ‒ 8, and 10 exhibited potent α-glucosidase inhibitory effects with IC50 values of 24.5 ± 1.9, 33.0 ± 0.5, 45.5 ± 0.1, and 23.8 ± 1.0 μM, respectively. All compounds (1 ‒ 10) showed considerable acetylcholinesterase (AChE) inhibitory effects with IC50 ranging from 30.1 to 75.2 μM.