Volatilome and derivatized metabolome via GC-MS of Heliotropium europaeum: antioxidant potential and anti-inflammatory activity with in-silico study

Abstract Heliotropium europaeum is a medicinal plant traditionally used for the treatment of inflammatory and skin disorders; however, t he volatile and derivatized metabolomic composition of the Algerian population remains largely unexplored. In this study, the volatile and derivatized metabolite composition of the aerial parts of Heliotropium europaeum collected from Hammam Righa (Algeria) was investigated using headspace solid-phase microextraction coupled with gas chromatography–mass spectrometry (HS-SPME-GC–MS) and gas chromatography–mass spectrometry (GC–MS) analyses before and after N , O -bis(trimethylsilyl)trifluoroacetamide (BSTFA) derivatization. The antioxidant and anti-inflammatory activities of the ethanolic extract were also evaluated. The volatile profile was mainly characterized by hexanal (53.9%), α-pinene (15.0%), limonene (3.2%), caryophyllene oxide (2.6%), and viridiflorol (2.5%). The crude ethanolic extract was dominated by linoleic acid (79.8%) and palmitic acid (13.8%), whereas derivatization revealed several polar metabolites, including glycerol (39.4%), sucrose (24.7%), and myo-inositol (6.6%). The extract exhibited significant antioxidant activity with 72.97% 2,2-diphenyl-1-picrylhydrazyl (DPPH) inhibition (IC₅₀ = 0.38 mg/mL) and high total antioxidant capacity, while moderate anti-inflammatory activity was observed in the bovine serum albumin (BSA) denaturation assay. The identified metabolites may collectively contribute to the observed antioxidant activity of the extract. Molecular docking analysis against xanthine oxidase and Keap1 identified linoleic acid, palmitic acid, hexahydrofarnesyl acetone, and myo-inositol as the compounds with the most favorable predicted binding affinities. These computational results provide preliminary mechanistic insights into the potential involvement of these metabolites in antioxidant-related pathways, including modulation of reactive oxygen species (ROS) generation and the Keap1/Nrf2 signaling pathway. However, these findings remain predictive and require further biochemical, cellular, and in vivo validation.