Caryophyllene-type sesquiterpenoids from the stembark of aglalia harmsiana and their cytotoxic activity against MCF-7 breast cancer cells

Abstract

Sesquiterpenoid is a class of terpenoid compounds that have the most abundant diversity of structures and biological activities that can be found in natural resources. Tropical plants are main source of sesquiterpenoid compounds such as Aglaia genus belong to Meliaceae family. A. harmsiana is a species from Aglaia that only has few previous researchs. Therefore, the purpose of this study was to isolate and determine the structure of sesquiterpenoid compounds from stem bark A. harmsiana along with their cytotoxic activity against MCF-7 breast cancer cells. The isolation process begins by extracting powder from A. harmsiana stembark using n-hexane, ethyl acetate and methanol. All extracts were evaluated for their cytotoxic activity against MCF-7 breast cancer cells, and n-hexane extracts showed significant cytotoxic activity with IC50 values of 117.86 µg/mL. Therefore, n-hexane extracts were further separated and purified by various chromatographic techniques to obtain compounds 1 and 2. Compounds 1 and 2 were elucidated their chemical structures by spectroscopic methods including IR, NMR, and MS as well as by comparison of data with literatures and identified as caryophyllene-type sesquiterpenoids, β-caryophyllene oxide (1) and senecrassidiol (2). Compounds 1 and 2 were submitted for cytotoxic eveluation on MCF-7 breast cancer cells and as a result, β-caryophyllene oxide (1) showed the stronger activity compared to senecrassidiol (2). These finding indicated that the cytotoxic activity of caryophyllene-type sesquiterpenoid are influenced by the presence of double bonds and configuration of methyl groups.