In Vitro Cholesterol-Reducing Activity of Ethanolic Extract of Namnam Leaves (Cynometra cauliflora L)

Hypercholesterolemia remains an important risk factor for cardiovascular disease and often requires long-term therapy, which may be accompanied by unwanted effects, including myopathy and hepatotoxicity. This has driven interest in safer plant-derived alternatives. Namnam leaves (Cynometra cauliflora L) contain flavonoids, saponins, and tannins, and an in vivo study reported lipid-lowering effects of their ethanol extract; however, no study has directly evaluated their in vitro anticholesterol activity. This study aimed to evaluate the in vitro anticholesterol activity of ethanolic extract of namnam leaves (Cynometra cauliflora L) and determine its EC50 value. The leaves were macerated with 96% ethanol, and extract was tested using the liebermann-burchard reaction measured by UV-Vis spectrophotometry. Anticholesterol activity was assessed at 100, 200, 300, 400, and 500 ppm, with simvastatin as the positive control. Data were analyzed using two-way ANOVA followed by Tukey's HSD test (α = 0.05). The extract showed increasing cholesterol reduction with increasing concentration, with mean (± SD) inhibition values of 7.99 ± 0.19%, 21.44 ± 0.12%, 35.27 ± 0.19%, 51.20 ± 0.19%, and 67.45 ± 0.19%, respectively. Linear regression yielded y=0.1487x-7.9805 (R=0.998), and the EC50 value was 389.916 ppm, compared with 148.94 ppm for simvastatin, indicating that simvastatin was approximately 2.6-fold more potent. At 500 ppm, the extract's inhibition did not differ significantly from that of simvastatin at 400 ppm (p = 1.000). Phytochemical screening confirmed the presence of flavonoids, saponins, tannins, and steroids in the extract. These findings indicate concentration-dependent in vitro cholesterol-reducing activity of the ethanolic extract of namnam leaves in this chemical assay, which warrants further mechanistic and biological confirmation before any therapeutic or pharmacological equivalence with simvastatin can be inferred.