The global trend towards sustainable development has encouraged the zero-waste approach of certain food by-products, to establish sustainable systems of production and consumption. Eggplant (Solanum melongena L.) by-products, particularly peel and calyx, are massively generated and usually discarded without further use despite their richness with beneficial phytochemicals. Therefore, this study aimed to investigate the phytochemical profile and anti-cancer activity of eggplant by-products. UPLC-QTOF-MS/MS phytochemical analysis, network pharmacology, molecular docking, and in-vitro cytotoxicity assay against prostate and cervical cell lines were conducted to investigate the phytochemical profile and anti-cancer potential of eggplant by-products. UPLC-QTOF-MS/MS analysis of eggplant peels and calyx afforded the identification of 50 and 41 secondary metabolites, respectively. The identified compounds mainly belonged to flavonoids and phenolic acid derivatives which showed high targeting towards cancer-related proteins through network pharmacology. Further, multi-target, multi-pathway network analysis showed the interactions of identified compounds with four key proteins including Akt-1, TNF-α, IL-1β and IL-6. Six bioactive compounds were docked to suggested key proteins according to network pharmacology findings, revealing that rutin has the best binding affinity to TNF-α, IL-1β and IL-6, while naringenin showed the best binding affinity to Akt-1. The suggested anti-cancer activity was confirmed by in-vitro cytotoxicity assay against prostate and cervical cancer cell lines which showed potent anti-cancer activity for peel (IC50 5.497 and 11.19 µg/ml) followed by calyx (IC50 17.76 and 28.06 µg/ml) and pulp (IC50 51.36 and 35.23 µg/ml), respectively. These results highlight the potential of eggplant by-products as a sustainable resource for developing functional foods and nutraceuticals.
Mady et al. (Sat,) studied this question.