Isolation of Cardamonin and Pinostrobin Chalcone from the Rhizomes of Boesenbergia rotunda (L.) Mansf. and their Cytotoxic Effects on H-29 and MDA-MB-231 Cancer Cell Lines

Background: Breast cancer and human colon cancer are the most common types of cancer in females and males, respectively. Breast cancer is the most common type of cancer after lung and colon cancers. Natural products are an important source for drug discovery. Boesenbergia rotunda (L.) Mansf. is commonly known as finger root, belonging to the Zingiberaceae family.

Objective: The aim of this study to isolate some natural compounds from the rhizomes of B. rotunda (L.) Mansf., and to investigate their cytotoxicity against the human triple-negative breast cancer cell (MDA-MB-231) and HT-29 colon cancer cell lines.

Methods: The dried rhizomes of B. rotunda were extracted with methanol. The methanolic extract was further used for solvent-solvent extraction. Bioassay-guided extraction and isolation of the rhizomes of the B. rotunda exhibited cytotoxic properties of hexane and dichloromethane fractions.

Results: Six major chemical constituents, pinostrobin (1), pinostrobin chalcone (2), cardamonin (3), 4,5-dihydrokawain (4), pinocembrin (5), and alpinetin (6) were isolated from the rhizomes of the B. rotunda. All the chemical constituents were screened against the human triple-negative breast cancer cell (MDA-MB-231) and HT-29 colon cancer cell lines. The compound cardamonin (3) (IC50 = 5.62±0.61 and 4.44±0.66 μg/mL) and pinostrobin chalcone (2), (IC50 = 20.42±2.23 and 22.51±0.42 μg/mL) were found to be potent natural cytotoxic compounds against MDA-MB-231 and HT-29 colon cancer cell lines, respectively.

Conclusion: Cardamonin (3) and pinostrobin chalcone (2) were found to be the most potential natural compounds against breast cancer cell line MDA-MB-231 and colon cancer HT-29 cell line.