Study of Antioxidant, Antiproliferative and DNA Damage Protecting Activities of Cinnamomum cassia Extracts Obtained by Sequential Extraction

Background: Cinnamomum cassia (C. cassia) is an evergreen tree in China and southern and eastern Asia. In traditional medicine, cinnamon is widely used due to its many bioactivity effects.

Objective: The aim of the present novel study is to evaluate and make comparison of antioxidant and antiproliferative activities of different extractions of C. cassia bark using seven solvents having different polarities. Solvents polarity gradients start with the solvent of lower polarity, n-hexane and end with water as the highest polar solvent. Among the extracts, acetone extract contains the highest phenolic and flavonoid contents; therefore it is assessed for the ability to protect DNA from damage.

Methods: The extracts are evaluated for total phenolic, flavonoid contents and antioxidant activities, using FRAP, DPPH, superoxide, and hydroxyl and nitric oxide radicals scavenging assays. DNA damage protecting activity of the acetone extract is studied with comet assay. Each of the extracts is studied for its antiproliferative effect against, MCF-7, MDAMB- 231(breast cancer) and HT29 (colon cancer), using MTT assay.

Results: The acetone extract exhibited the highest FRAP value, phenolic and flavonoids contents when compared to the other extracts and could protect 45% mouse fibroblast cell line (3T3-L1) from DNA damage at 30 μg/ml. The lowest IC50 value in DPPH, superoxide and hydroxyl radicals scavenging was noticed in ethyl acetate extract. IC50 value obtained for the hexane extract was the lowest compared to the other extracts in scavenging nitric oxide radicals. The hexane extract showed the highest antiproliferative effect against cancer cells followed by the chloroform extract. The ethyl acetate extract inhibited the proliferation of only MCF-7 by IC50 of 100 μg/ml, while the other extracts exhibited no IC50 in all the cancer cells.

Conclusions: C. cassia shows promise antioxidant and anticancer activities with significant DNA damage protecting effect.

Keywords: Antioxidant; Antiproliferative activity; Cinnamomum cassia; DNA damage protecting activity; Free radical scavenging activity; HT29; MCF-7; MDA-MB-231.