**5. Conclusions**

To conclude, the results from the present study provide an understanding of the cytotoxic effect of *Pistacia vera* red hull. Cytotoxicity studies of *Pistacia vera* red hull ethyl acetate (PV-EA) extract on different cancer cell lines and subsequent chemical purification of bioactive PV-EA have led to the isolation of gallic acid and quercetin. Purified compound (F13b1/PV-EA) was shown to possess cytotoxic effects against MCF-7 cells. This finding may have an impact on the future of cancer treatment by providing another positive avenue for the discovery of a combined anticancer drug treatment that may promote induced apoptosis.

**Author Contributions:** M.S. carried out the tests analyzed the data and wrote the manuscript; R.F. analyzed the data and wrote the manuscript; F.N. designed and analyzed the data and wrote the final draft of the paper and proof read the manuscript; J.B.M. designing the experimental work and proof reading the manuscript; N.A.M. designing the experiments and analyzed data. All authors have read and agreed to the published version of the manuscript.

**Funding:** This paper was supported by a grant from the University Malaya (GPF006B -2018).

**Conflicts of Interest:** The authors declare no conflict of interest.

### **References**


**Sample Availability:** Samples of the compounds are available from the authors.

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