First investigation of the chemical composition, antioxidant, antimicrobial and larvicidal activities of the essential oil of the subspecies Ononis angustissima Lam. subsp. filifolia Murb.

This study is the first to explore the essential oil of Ononis angustissima Lam. subsp. filifolia Murb., a subspecies growing in the Algerian northeastern Sahara. The chemical composition was evaluated by GC/GC-EIMS. Antioxidant activity was evaluated using two methods. Thirty-four (91.6%) individual components were identified. The main constituents were linalool (12.6%), hexahydrofarnesylacetone (8.4%), β-eudesmol (6.6%), α-cadinol (6.4%) and T-cadinol (6.1%). The findings provide a chemical basis for understanding relationships between North African subspecies, supporting botanical and genetic classification. The oil exhibited moderate scavenging activity against DPPH radicals (IC 50 = 102.30 µg/ml) and high activity in the β-carotene bleaching assay (91.346%). Antimicrobial tests revealed effectiveness against Gram-positive bacteria ( Staphylococcus aureus ATCC 25923 and ATCC 43300), limited impact on Gram-negative bacteria ( Pseudomonas aeruginosa ATCC 27853 and Escherichia coli ATCC 25922), and good inhibition against Aspergillus niger and Scedosporium apiospermum . A notable larvicidal activity was observed against Date Moth, particularly on L2 larvae.