Exploring the potential of Inula viscosa extracts for antioxidant, antiproliferative and apoptotic effects on human liver cancer cells and a molecular docking study.

In folk medicine, Inula viscosa (Asteraceae) has been traditionally utilized for treating various ailments, including diabetes, bronchitis, diarrhea, rheumatism, and injuries. In this study, we aimed to investigate the chemical composition, antioxidant, antiproliferative, and apoptotic properties of I. viscosa leaf extracts. Extraction was performed using solvents of varying polarities. Antioxidant activity was determined using Ferric reducing antioxidant power (FRAP) and 2,2-azinobis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) assays. The results revealed that aqueous ethanol (70%) and aqueous ethyl acetate (70%) extracts contained high levels of phenols (645.58 ± 8.77 mg CE/g) and flavonoids (180.69 ± 1.54 mg QE/g), respectively. Aqueous ethanol (70%) extract exhibited the highest antioxidant activity with IC50 of 572.74 µmol TE/g DW (µmol Trolox equivalent in 1g of dry extract) in the ABTS assay and 76862.06 µM TE/g DW in the FRAP test. All extracts showed a considerable dose-dependent cytotoxic effect on cancerous HepG2 cells (P < 0.05). The aqueous ethanol extract demonstrated the highest inhibitory effect (IC50 = 1.67 mg/ml). Treatment with aqueous ethanol (70%) and pure ethyl acetate extracts significantly increased the number of apoptotic cells to 8 and 6%, respectively, in HepG2 cells (P < 0.05). Additionally, the aqueous ethanol extract significantly elevatedreactive oxygen species (ROS) levels (53%) in HepG2 cells. The molecular docking study identified paxanthone and banaxanthone E as the compounds that exhibited the highest binding affinities with BCL-2. This study demonstrated the potent antioxidant, antiproliferation, and intracellular ROS production of I. viscosa leaf extracts. Further studies should be conducted to identify the active compounds involved.

Characterization by liquid chromatography-mass spectrometry and antioxidant activity of an ethanolic extract of Inula viscosa leaves.

Inula viscosa (I. viscosa) is a common Mediterranean plant, well known for its content on bioactive molecules. The chemical composition of an ethanolic extract from I. viscosa leaves, growing in Algeria, was analysed by liquid chromatography coupled to photodiode array detection and electrospray ionization mass spectrometry (LC-DAD-ESI-MS/MS) operating in negative and positive mode. The methodology used revealed the presence of 51 compounds from which 47 were putatively identified, including 11 phenolic acids, 23flavonoids, one lignan and 12 terpenoids. Twenty-six of these compounds are described for the first time in I. viscosa. Antioxidant activity was measured using three different and complementary chemical assays: DPPH radical scavenging activity, oxygen radical absorbance capacity (ORAC) and hydroxyl radical scavenging capacity (HOSC). Results demonstrate that ethanolic leaf extract exhibit a high scavenging ability against DPPH (157.72 ±â€¯6.45 µM TE/g DW), peroxyl (4471.42 ±â€¯113.16 µM TE/g DW) and hydroxyl (630.10 ±â€¯17.81 µM TE/g DW) radicals, indicating that I. viscosa can be a promising source of bioactive compounds.