Abstract

Background: Quassinoids and canthin-6-one alkaloids are bioactive markers of Eurycoma longifolia (EL) and E. harmandiana (EH) and have been commercially utilized to treat inflammation and male infertility. Objectives: This study aims to reveal the contents of bioactive compounds and compare anti-inflammatory activities of these two species. Methods: HPLC methods coupled with UV-Vis detection were developed and validated for the simultaneous analysis of the chemical profiles and their contents in EL and EH. The anti-inflammatory activities of both species were investigated using RAW 264.7 cell line. Results: The HPLC methods provided a sensitivity (LOD) of 0.02-0.05 μg/mL for the eight bioactive compounds (canthin-6-one alkaloids, quassinoids, and scopoletin) with high precision (% relative standard deviation (RSD) ≤6.48) and recoveries between 80.0 and 120%. The chaparrinone: eurycomanone ratio was high in EH, whereas EL had a higher ratio of eurycomanone: chaparrinone than EH. The contents of total canthin-6-one alkaloids, quassinoids, and scopoletin were 0.01-0.75, 0.19-1.54, and 0.01-0.28 mg/g, respectively, in EL roots and 0.12-1.80, 7.05-9.26, and 0.02 mg/g, respectively, in EH roots. The anti-inflammatory effects of EL and EH extracts varied among the samples due to the variation in their chemical constituents. Conclusions: In summary, our study indicated that chaparrinone was the major compound in EH. EH exhibited anti-inflammatory activity to the same extent as EL. Highlights: EH and EL extracts were analyzed using developed HPLC-UV methods, revealing a high concentration of chaparrinone in EH, and an anti-inflammatory assay indicated that EH had a potency comparable to that of EL.