In silico and in vitro evaluation of the anti-inflammatory activity of the flavonoids of Strobilanthes sp. (Acanthaceae) collected from Kalimantan, Indonesia, towards the COX-2 enzyme for a nutraceutical with anti-inflammatory properties

Wild Strobilanthes leaves are edible and used to treat external wounds. Leaf extracts contain flavonoids such as apigenin, catechin, epicatechin, kaempferol, luteolin, myricetin, naringenin, quercetin, and rutin. This study investigated the molecular interactions of Strobilanthes flavonoids with COX enzymes, predicted their ADMET profiles, and validated the results using an in vitro enzymatic assay of the extract of Strobilanthes sp. (EES) collected from Kalimantan, Indonesia. HPLC analysis of the flavonoids in the EES was also carried out. The flavonoids bind to the COX active site with a pattern similar to that of COX-2 inhibitors. ADMET predictions indicate moderate pharmacokinetic properties. The estimated selectivity index reveals that myricetin has the potential to selectively inhibit COX-2, while apigenin, catechin, luteolin, naringenin, and quercetin are preferential COX-2 inhibitors. EES inhibited prostaglandin production with an IC50 of 74.359 µg/mL, weaker than celecoxib (IC50 of 0.237 µg/mL). EES contains catechin, myricetin, and quercetin. Overall, Strobilanthes sp. can be developed into a nutraceutical or food supplement with anti-inflammatory properties that support health.