Structure-based experimental and theoretical analysis of Ricinus communis for their HepG2 human carcinoma cell line inhibitors

Abstract

Castor (Ricinus communis) plant has been utilized for essential oils for a long time but has not been investigated for the isolation of bioactive secondary metabolites. The prospective medicinal effects of the castor plant inspired us to investigate phytochemically, chromatographically, and biologically for anticancer and anti-urease activities. Plant seeds were ground to separate kernel and extracted by methanol. Different extracts were analyzed for the presence/absence of different classes of naturally occurring bioactive compounds. Alcoholic extract of Ricinus communis further proceeded to purification by column and thin-layer chromatography. Resultantly, a series of seven phenolic acid derivatives; 3,4,5-trihydroxy benzoic acid (1), 3,4,5-trihydroxymethyl-benzoate (2), p-hydroxycinnamic acid ((E)-3-(4-hydroxyphenyl)acrylic acid, 3), (E)-3-(3,4-dihydroxy phenyl)acrylic acid (4), (E)-3-(3-hydroxy-4-methoxyphenyl)acrylic acid (5), (E)-nonyl-3-(3hydroxy-4-methoxyphenyl)acrylate (6) and (E)-docosyl-3-(4-hydroxyphenyl)acrylate (7) were obtained. Pure compounds were characterized by spectroscopic (1H-NMR, 13C-NMR, and mass spectrometry) techniques to elucidate their structures. In addition, the purified compounds were evaluated for their in vitro anti-cancer and anti-urease activities. Among these, compounds 1–5 presented good biological activity results, while compounds 6 & 7 showed lower values for anti-cancer activity. However, all the compounds were found inactive for anti-urease inhibition. Molecular docking results revealed that the structures of these compounds are very compatible and flexible to capture the target protein cells as an inhibitor. In conclusion, Ricinus communis extract is a prolific source of bioactive entities and might be a promising alternative in the pharmaceutical and food industries due to its significant biological potentialities.