Cytotoxic activity of proteins extracted from fennel (Foeniculum vulgare) seeds against human cancer cell lines

Abstract

Fennel (Foeniculum vulgare) is an aromatic flowering medicinal plant classified into the family Umbelliferae (Apiaceae). It is native to southern Europe and the Mediterranean region with a long history of use by humans as a spice, fresh vegetable, and in traditional folk medicine. Despite its popularity for its medicinal value, the majority of data in scientific literature is based on the crude extracts and essential oils such as trans‐anethole and estragole, fenchone, limonene, and 1‐octen‐3‐ol. Besides, other phytochemicals found from seeds are polyphenols, included rosmarinic acid and luteolin, etc. In present study, we investigated the anticancer potential of proteins purified from fennel seeds against human breast cancer MCF 7 and pancreatic cancer AsPC‐1 cell lines. The crude fennel extract was partially purified using anion‐exchange and size exclusion chromatography techniques to have a comparative analysis for activity guided fractionation. For anion‐exchange chromatography (HiTrap‐Q FF 5ml column in 20mM Tris/HCl, pH 8.00 buffer) and for gel filtration (HiPrep Sephacryl S‐200 HR16/20 column in 20mM, pH 8.00 buffer ) were used. The crude extract and fractions collected were judged for their purity by 10% Tris‐tricine SDS‐PAGE gel electrophoresis. The MTT assay results exhibited that both anion‐exchange and gel filtration fractions demonstrated significant cytotoxic activity against MCF‐7 breast cancer cell line with cell inhibition in a range of 65–80% at 100μg/ml. In contrast, evaluation againist AsPC‐1pancreatic cancer cell line revealed non‐significant inhibition by fractions obtained from both methods. Further work is in progress to identify and fully characterized the primary structure of cytotoxic proteins by mass spectrometry and Edman protein sequencing.