METHYL 10-EPI-PHEOPHORBIDE A FROM MCF-7 CELLS ACTIVE LAYER OF THE INDONESIAN FICUS DELTOIDEA JACK LEAVES

Abstract

Objective: To isolate and elucidate a cytotoxic principle against breast tumor MCF-7 cells of the Indonesian terrestrial plant Ficus deltoidea Jack leaves.Methods: F. deltoidea leaves collected at National Park of mount Gede-Pangrango, Indonesia have been subjected to chemical and biological work. F. deltoidea leaves were extracted with 96% aqueous ethanol (EtOH) and was then partitioned into three layers n-hexane, dichloromethane (CH2Cl2), and n-butanol (n-BuOH). All layers were checked for their activity against breast tumor MCF-7 cells using MTT assay method. A portion of the most active layer was purified using open column chromatography to give fraction that has toxicity against zebra fish embryos. Based on the assay-guided isolation, compound 1 was isolated. The chemical structure of 1 was elucidated using nuclear magnetic resonance (NMR) and high-resolution mass spectrometry (HRMS) data as well as comparing data with literature.Results: The CH2Cl2 layer of F. deltoidea leaves was found to inhibit breast tumor MCF-7 cells with IC50 10 µg/ml which was the most toxic among the layers. A portion of the most active layer was purified using open column chromatography to give 7 fractions. The fraction 5 showed toxicity against zebrafish embryos (LC50 35 µg/ml, 48 hpf). This fraction was purified using high performance liquid chromatography (HPLC) octadecylsilyl (ODS) column with gradient elution 70% aqueous acetonitrile (MeCN) to 100% MeCN (linear gradient) for 40 min with UV detection at 254 nm (tR = 30.99 min) to give compound 1. The chemical structure of 1 was revealed as a chlorin-type compound named methyl 10-epi-pheophorbide A.Conclusion: Methyl 10-epi-pheophorbide A was isolated for the first time from the active fraction of the Indonesian F. deltoidea leaves or tabat barito. The chemical structure including absolute stereo chemistry was elucidated using NMR and HRMS data as well as by comparison with the literature values. The 13C NMR data has been added to complete the previous report.