Samannachan: A Thai traditional herbal recipe with cytotoxic potential against breast, cervical, and ovarian cancers

Background: Samannachan (SMC) is a Thai traditional herbal recipe that has been used since 2005 at Khampramong Temple, Sakon Nakhon, to treat more than 6,000 cancer patients. However, scientific evidence supporting cytotoxic effects remains limited.Objectives: The objective of the study is to evaluate the cytotoxicity of the SMC recipe and its ten herbal components against breast, cervical, and ovarian cancer cells compared to normal cells. Methods: Cytotoxic activity was assessed using the sulforhodamine B (SRB) assay on breast (MCF-7, T47D, MDA-MB-231), cervical (HeLa), and ovarian (SK-OV-3) cancer cell lines, as well as on non-cancerous human keratinocytes (HaCaT). Both aqueous and 95% ethanol extracts of the SMC formula and its individual herbs were examined. High-performance liquid chromatography (HPLC) was used to identify and quantify key active cytotoxic compounds. Results: The ethanolic SMC extract showed moderate cytotoxicity against MCF-7, HeLa, T47D, and MDA-MB-231 (IC50 41.10–78.35 μg/mL). Among the plant extracts, the ethanolic and aqueous extracts of Coscinium fenestratum exhibited the strongest cytotoxic effects against HeLa and MCF-7 cells with IC50 values of 5.10 ± 0.38 (SI = 4.98) and 16.07 ± 1.11 μg/mL (SI = 4.99), respectively. Furthermore, the ethanolic extract of Caesalpinia sappan demonstrated the most potent cytotoxic activity against T47D cells, with an IC50 value of 7.32 ± 2.14 μg/mL (SI = 1.19). Berberine exhibited potent cytotoxicity (IC50 < 4 μg/mL). HPLC identified brazilin (40.25 mg/g of extract) and berberine (2.41 mg/g) as major active compounds. Conclusion: The SMC ethanolic extract exhibited moderate cytotoxicity, while C. fenestratum and C. sappan showed high activity. Berberine and brazilin may serve as chemical markers. Further in vivo and mechanistic studies are needed to validate SMC as a complementary cancer therapy.