Chemical Profiling and Selective Antiproliferative Activity of Orange Peel (Citrus sinensis) Extract Against MCF-7 and HepG2 Cells

The results of the analysis conducted using the GC-MS demonstrate that the orange peel's alcoholic extract is composed of multiple different compounds, including flavonoids and terpenoids. 1-Methyl-4-(1-methylethinyl)cyclohexene represents the largest portion of these multiple components at 38.89%, while the hesperidin derivative makes up 21.19% of the composition as well. The cytotoxicity analysis revealed a clear concentration-dependent cytotoxic effect on MCF-7 breast cancer cells; with an IC50 value of approximately 3 μM at 24 h, compared to 1.74 μM for doxorubicin, that indicates a strong antiproliferative activity. As the extract was tested with no significant effect found at IC₅₀ of greater than 50µM on HepG2 cells, it does not appear to have much potential as an inhibitor. Meanwhile, there was no apparent impact from the extract based on measured parameters at all levels (IC₅₀>50>100) in terms of inhibitory activities against HepG2, with an IC₅₀ approximately equal to 3.2% (tube) and 2.6% (beaker) at their maximum concentration yielding an inhibition rate near 99% suggests that orange peels are very high in the number of phenolic antioxidant compounds. These results reinforce the possibility of considering orange peel as a promising source of plant compounds with antioxidant and selective antiproliferative effects.