Free radical scavenging and antibacterial activity of essential oil and solvent extracts of Iris planifolia (Mill) from Algeria

Abstract

Free radical scavenging and antibacterial activity of essential oil and solvent extracts of Iris planifolia (Mill) was investigated. The essential oil was analyzed by Gas chromatography mass spectrometry (GC-MS) and a total of 38 types of volatile organics were identified. The essential oil consists chiefly of alkanes (36.5%), acids (19.1%), ketones (11.7%), alcohols (9.0%), arylpropanoids (6.8%) and aldehydes (4.1%) accompanied by relatively much smaller amounts of monoterpenes (1.0%). The antimicrobial activity of essential oil and ethanolic extract shows an important activity against Salmonella typhimurium and Klebsiella pneumoniae with minimum inhibitory concentration (MIC) of 3.12 mg/ml. Furthermore, the free radical scavenging assay of the essential oil and extracts were determined using a 2,2-diphenyl-1-picrylhydrazyl (DPPH) test system. The dichloromethane and water extract possessed strong radical scavenging activity with the lowest IC50 value of 0.1 mg/ml followed by the aqueous extract with an IC50 value of 0.12 mg/ml. Phytochemical analysis revealed the presence of flavonoids, terpenoids, saponins, alkalois and tannins which may be responsible for antimicrobial and antioxidant activities.