Hydroperoxycycloartenols from Euphorbia hirta Linn. (Euphorbiacae)

• Main Author: Cornelio, Kimberly
• Format: text
• Language: English
• Published: Animo Repository 2012
• Subjects: Dichloromethane; Medicinal plants; Chemistry
• Online Access: https://animorepository.dlsu.edu.ph/etd_masteral/4104; https://animorepository.dlsu.edu.ph/context/etd_masteral/article/10942/viewcontent/CDTG005094_P.pdf
• Institution: De La Salle University

The dichloromethane extracts of Euphorbia hirta stems afforded taraxerone (1) from EHS2, a mixture of 25-hydroperoxycycloart-23-en-3-b-ol (2a) and 24-hydroperoxycycloart-25-en-3-b-ol (2b) from EHS4, and another mixture of cycloartenol (3a), lupeol (3b), a-amyrin (3c) and b- amyrin (3d) from EHS1. The leaves afforded a mixture of 3a-3d from EHL1 and a mixture of 2a and 2b from EHL2, while the roots yielded a mixture of 3a-3d from EHR3, a mixture of Lupeol unsaturated fatty acid ester 4a, cycloartenol unsaturated fatty acid ester 4b, α-amyrin unsaturated fatty acid ester 4c, and b-amyrin unsaturated fatty acid ester 4d from EHR4 and a mixture of b-sitosterol 5a and Linoleic acid 5b from EHR5. The structures of Taraxerone, 25-hydroperoxycycloart-23-en-3-b- ol and 24-hydroperoxycycloart-25-en-3-b-ol were elucidated by extensive 1-D and 2-D NMR spectroscopic techniques, while the structures of the other isolates were verified by comparison with published data. EHS2 and EHL2 were subjected to antimicrobial activity tests and both have shown activity against P.aeruginosa (AI=0.2 and 0.3) and S. aureus (AI=0.6 and 0.5). EHL2 also showed activity against C.albicans (AI=0.2) and T. mentagrophyte (AI=0.6). The aforementioned isolates were also subjected to cytotoxicity assay, together with EHS1, and results have shown that only EHL2 has a cytotoxic activity against human colon adenocarcinoma HCT11G (IC50=4.7895) cancer cells and lung cancer cell line AS49 (IC50=3.8992). But compared to Doxorubicin, EHL2 has a less potent cytotoxic activity based on its higher IC50 value.