Phytochemical, Antioxidant and Antitumor Studies of Coumarins Extracted from Granny Smith Apple Seeds by Different Methods
Raghad Riyadh Khalil, Yasser Fakri Mustafa.
The management of many human diseases linked to oxidative stress requires extensive research to explore novel agents with a potential antioxidant activity. In this study, the seeds of Granny Smith apples were extracted by four solvents; water, methanol, chloroform, and n-hexane. Extraction was performed using three techniques, which are kinetic maceration, ultrasound- and microwaves- facilitated extraction methods. These methods were carried out in three styles including non-serial, serial descendingly- and ascendingly- ordered in polarity. Phytochemical screening tests performed on the resultant extracts indicated the presence of coumarins in the methanol and chloroform extracts obtained from the applied techniques and styles. Five novel simple coumarins were isolated and their chemical structures elucidated by matching their physical properties and spectral data with those found in literature. Two in vitro biological activities were studied for the isolated products; the antioxidant strength which was studied by examining their capacity to scavenge DPPH and hydroxyl free radicals, and prefatory antitumor activity which was tested by MTT versus HeLa and MCF-7 cancer cell lines. The results showed that the isolated coumarins have promising free radicals scavenging capacity and antitumor activity with superiority to compounds R3 and R5. It is concluded that there is a positive correlation between the antioxidant activity of the isolated coumarins and their antitumor activity.