Chemical composition and bioactivity of supercritical CO 2 extracts of Helichrysum italicum , Helichrysum plicatum , Helichrysum sanguineum and Helichrysum stoechas

Abstract BACKGROUND This study investigates the supercritical carbon dioxide (ScCO 2 ) extraction method for obtaining chemical profiles and biological activities of four Helichrysum species: Helichrysum italicum (Roth) G. Don, Helichrysum plicatum DC., Helichrysum sanguineum (L.) Kostel. and Helichrysum stoechas (L.) Moench. ScCO 2 extraction is regarded as an efficient and environmentally friendly technique for producing high‐quality plant extracts; however, comparative data on bioactivity and chemical composition among Helichrysum species remain limited. RESULTS Aerial parts of the species were collected and extracted using ScCO 2 at 20 MPa and 40 °C. The extracts were analyzed for chemical composition and phenolic profiles, and their antioxidant, α ‐glucosidase inhibitory and antimicrobial activities were evaluated. The highest extraction yield was obtained from H. italicum (28.7 g kg −1 ), whereas H. stoechas showed the lowest yield (10.4 g kg −1 ). Gas chromatography–mass spectrometry analysis identified ( Z )‐13‐octadecenal (0–27.11%) and 9‐octadecenoic acid (33.18–58.79%) as the dominant constituents across the species, indicating a clear prevalence of unsaturated fatty acids in ScCO 2 extracts. Phenolic composition varied among species, with luteolin identified as the predominant compound in all extracts. Helichrysum plicatum exhibited the highest antioxidant capacity based on 2,2'‐azino‐bis(3‐ethylbenzothiazoline‐6‐sulfonic acid) (i.e. ABTS)• + radical scavenging activity [i.e. extract concentration providing 50% inhibition (IC 50 )], whereas H. sanguineum showed the strongest α ‐glucosidase inhibitory activity (IC 50 ). Antimicrobial assays demonstrated moderate to strong inhibitory effects against both bacterial and yeast strains. Furthermore, ADMET analysis indicated favorable acute toxicity and pharmacokinetic profiles for major phytochemicals, and molecular docking revealed that luteolin, epicatechin and chlorogenic acid exhibited the most favorable binding affinities with selected target proteins. CONCLUSION The results demonstrate that ScCO 2 extracts of Helichrysum species possess notable bioactive properties, with significant interspecific variation in chemical composition and biological activity, highlighting their potential for pharmaceutical and cosmetic applications. © 2026 Society of Chemical Industry.