Phytochemical profiling, antioxidant and anticancer potential of Citrus limetta peel extract against A431 skin cancer cell line

Citrus limetta is a widely consumed fruit worldwide, and its peel is rich in antioxidant-abundant polyphenols. This research investigates the phytochemical screening, antioxidant potential, and anti-cancer effect of Citrus limetta peel extract against A431 cell lines. Preliminary phytochemical screening of petroleum ether, ethyl acetate, chloroform, methanol, ethanol, and aqueous extracts revealed that the methanolic, ethanolic, and aqueous extracts were rich in phenolic, flavonoids, tannins, and triterpenoids. Quantitative analysis showed that the highest phenolic (22.69 ± 0.25 mg GAE/g) and flavonoid content (32.97 ± 0.14 mg QE/g) was observed in the ethanolic extract, whereas the aqueous extract showed the highest tannin content (24.84 ± 0.23 mg GAE/g). Chromatographic profiling confirmed the presence of hesperidin as a major bioactive constituent. TLC and HPLTLC analyses showed that the Rf values of the ethanolic extract were comparable to those of hesperidin. HPLC analysis revealed hesperidin content (27.4 mg/g) in the ethanolic extract. Antioxidant assays revealed that the ethanolic extract exhibited the strongest radical scavenging activity through DPPH, H₂O₂, ABTS, and FRAP assays. The ethanolic extract was further evaluated for cytotoxicity on A431 cell lines. A concentration-dependent decrease in cell viability was observed following 16 h treatment, with an IC₅₀ value of 3 μg/mL. The study highlights the potential of citrus peel as a sustainable and promising candidate for skin cancer management. Further in vivo investigations are required to validate its therapeutic potential.