Phorbol esters from Croton tiglium leaves and their antibacterial and cytotoxicity activities

Croton is a genus of the family Euphorbiaceae, known to have around 1300 species worldwide. Several species have a long history in traditional medicine. In the ayurvedic system of medicine, the Croton tiglium seed oil is used to ease various illnesses, including obstinate constipation, intestinal obstruction, lead poisoning, and high blood pressure [ 1 ]. Croton tiglium contains phorbol esters, which have a wide range of biological activities, such as cytotoxicity, anti-inflammatory, and antitubercular effects [ 2 ]. The present study aims to evaluate the antibacterial activity of C. tiglium leaf extracts, identify bioactive phytochemical compounds, and assess their anticancer potential against MDA-MB 231 breast cancer cells. The hexane extract, which mainly contains hydrocarbons demonstrated the highest antibacterial activity against Staphylococcus aureus , with with a Minimum Inhibitory Concentration of 12.5 μg/mL and Minimum Bactericidal Concentration of 25 μg/mL. Four novel and eight known phorbol esters were isolated using chromatographic techniques, including gravity column chromatography, autopurification system, and semi-preparative HPLC. Their structures were elucidated using spectroscopic methods. These compounds were screened for cytotoxicity against MDA-MB 231 cells. While no compounds exhibited significant activity, 20-acetyl-12- O -acetyl-4α-deoxyphorbol-13-(2-methyl)butyrate reduced cell viability to 67.8% ([ Fig. 1 ]). Fig. 1 20-acetyl-12- O -acetyl-4α-deoxyphorbol-13-(2-methyl)butyrate Publication History Article published online: 05 March 2026 © 2026. Thieme. All rights reserved. Georg Thieme Verlag KG Oswald-Hesse-Straße 50, 70469 Stuttgart, Germany