Isolation and purification of sinensetin, and in silico screening of phytochemicals from <i>Orthosiphon aristatus</i> (Blume) Miq. for anti-breast cancer activity

<i>Orthosiphon aristatus</i> (Blume) Miq. (<i>O. aristatus</i>), a traditional herbal medicine, exhibits a wide range of biological activities but its anti-breast cancer effect is not fully established. In this study, sinensetin was isolated and purified through a multistep process, beginning with liquid-liquid partitioning using dichloromethane, followed by classic column chromatography using gradient elution. Preparative high-performance liquid chromatography with acetonitrile-water (41:59, v/v) mobile phase successfully isolated sinensetin to 95% purity. <i>In silico</i> screening of <i>O. aristatus</i>-derived bioactive compounds revealed that flavonoids (including sinensetin), polyphenols (i.e. 2,3-O-dicaffeoyltartaric acid, rosmarinic acid), diterpenoid (i.e. trans-ozic acid), triterpenoids and dipeptide (i.e. aurantiamide acetate) have good binding affinities with 17β-HSD1, ErbB2/HER2 and PI3K-PKB/Akt proteins. These findings suggest that <i>O. arsistatus</i> could be a rich natural source of inhibitors targeting molecular pathways involved in breast cancer, offering promising therapeutic benefits.