Biochemical profiling of Satureja horvatii Šilić, Lamiaceae extracts: Experimental and molecular docking aspects

Satureja horvatii Šilić is an endemic species of the Balkan Peninsula traditionally used in many tea blends, yet insufficiently explored. This study aimed to evaluate the ethanol extracts and herbal infusion of this species in terms of phenolic composition, antioxidant activity, and anti-HIV potential of its constituents. The total phenolic and flavonoid content of herbal infusion and 70 % (v/v) ethanol extracts was determined spectrophotometrically, while detailed chemical characterization by high pressure liquid chromatography coupled with diode array detection (HPLC-DAD). Antioxidant activity was evaluated by the ability of extracts to neutralize 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical. The antiviral potential of compounds was tested against cysteine-cysteine chemokine receptor type 5 (CCR5) by molecular docking. The major bioactive components of the extracts were rutin (30.90–69.40 mg/g dry extract (de)), rosmarinic (13.10–45.30 mg/g de), and p-coumaric acid (14–35.50 mg/g de). The extracts exhibited significant DPPH radical scavenging potential (IC₅₀ values ranging from 4.63 to 9.94 μg/mL). In the molecular docking study, flavonoid derivates – naringenin, epicatechin, quercetin; and chlorogenic acid among the phenolic acids had a high binding affinity toward CCR5 and interacted with key residues at the active site of the target receptor. S. horvatii extracts show promising antiviral potential and are worthy of further research in discovering novel anti-HIV therapy.