Fig 2: Per-residue contributions to binding energy of olive-derived compounds to COX-1 and COX-2. (A) Heatmap of key residues contributing to binding energy for OLC and OLP bound to each chain of COX-1 and COX-2 homodimers. Energy contributions are shown in kcal/mol as an average of three independent binding free energy calculations using MM-PBSA. The asterisk* indicates amino acid difference between COX isoforms. (B) OLC and OLP binding to COX-1 and (C) COX-2, with key residues highlighted in stick representation. Oxygens atoms are red, nitrogen atoms are blue, and hydrogen atoms are white.

Fig 3: Cox-1 inhibitor assay.(A) Chemical structures of all the tested compounds. MCS structures are also depicted which helped to intuitively assess the structural similarity between the tested compounds (B) An example relative fluorescent units (RFU) plot of the tested compounds at 100μM (other tested conc.: 12.5μM to 400μM serial dilutions). SC560 is a positive control provided by the assay kit supplier (Materials and methods). (C) Relative inhibition of the positive control (drug triflusal), test compound (5-methoxy salicylic acid) and negative control (4-isopropyl benzoic acid) at different tested concentrations. 5-methoxy salicylic acid showed similar inhibition of Cox-1 as the drug triflusal whereas no such inhibition was observed for 4-isopropyl benzoic acid. 4-isopropyl benzoic acid showed strong color change (bright pink) reaction beyond 100μM and thus was found unsuitable for being tested at higher concentration with this assay.

Fig 4: Dynamics of olive-derived compounds bound to the active site of COX-1 and COX-2. (A) RMSD of OLC and OLP bound to the catalytic site of each chain of COX-1 and (B) COX-2 with respect to its initial structure. (C) Number of hydrogen bonds between olive compounds and COX-1 and (D) COX-2. (E) Number of pairs within 0.35 nm between olive compounds and COX-1 and (F) COX-2. Data is shown as mean ± SD.

Fig 5: Drug-food compound similarity.(A) Number of hits retrieved from each split-sets model. (B) 200 drug-food pairs predicted as ‘match’ at the probability threshold of >0.5. The drugs are arranged according to their therapeutic class and food compounds according to their food source. The highlighted colored links represent the case examples in the five author defined groups (details in the text). (C) Group4-probable lead example taken up for experimental validation. The food compound 5-methoxysalicylic acid was a hit with the drug triflusal which has 4 known targets. We validated the inhibitory activity of triflusal and 5-methoxysalicylic acid against the target PTGS1 (also known as Cox-1).