Anti-inflammatory effects and HPLC-PDA quantification of the triterpene saponin-enriched extract of <i>Combretum trifoliatum</i> leaves

For the first time, the <i>in vitro</i> anti-inflammatory activity against Nitric oxide (NO) overproduction <i>via</i> Lipopolysaccharide (LPS) injection on RAW264.7 cells as well as the quantitative determination of triterpene saponin-enriched extract from the <i>Combretum trifoliatum</i> leaves (SE-CTL) <i>via</i> High-Performance Liquid Chromatography (HPLC) using Photodiode Array Detector (PDA) technique was investigated. The SE-CTL significantly exhibited the best inhibition of NO (IC₅₀ value of 46.39 ± 3.02 µg/mL). Accordingly, qualitative and quantitative analyses of two main triterpene saponins (<b>1</b> & <b>2</b>), were clearly and extensively concentrated by the HPLC-PDA method. Two primary markers (<b>1</b> & <b>2</b>) displayed a good linearity (R² > 0.999) in a relatively wide concentration (ranged from 6.25 to 100 µg/mL). The LOD and LOQ of them were respectively in the range of 2.08-3.12 and 6.94-10.42 µg/mL. Their recoveries were evaluated in the range of 98.56-101.58%. The concentrations of markers in SE-CTL were 0.040 and 0.013% (<i>w</i>/<i>w</i>), respectively.