CHEMICAL COMPOSITION, EVALUATION OF RADICAL SCAVENGING AND ANTIBACTERIAL ACTIVITIES OF ESSENTIAL OIL LEAVES OF MENTHA LONGIFOLIA (L.) HUDSON SUBSP. SCHIMPERI (BRIQ.) BRIQ. CULTIVATED IN ADEN GOVERNMENT, YEMEN

Abstract

This is the first report on the chemical composition, radical scavenging and antibacterial activities of essential oil obtained from the leaves of cultivated Mentha longifolia (L.) Hudson, subs. schimperi (Briq.) Briq., in Aden-Yemen. Gas chromatography/mass spectrometry analysis of the hydro-distillated essential oil revealed eighteen compounds representing 100 % of total oil. The main components detected were pulegone (46.3624%), eucalyptol (10.5653%), and menthone (9.5726%). Determination of the total content of phenols and flavonoids revealed the presence of 11.653 mg GAE /g and 12.310 mg QE/g, respectively. The antioxidant activity performed using DDPH radical showed that the sample concentration necessary to inhibit 50% of DPPH radicals (IC₅₀) was 28.3837 μg/mL, indicating a strong antioxidant activity. Regarding the antibacterial activity, the essential oil showed moderate-to-strong broad-spectrum antibacterial activity against the four tested bacterial strains (Staphylococcus aureus ATCC 29213, Enterococcus faecalis ATCC 29212, Escherichia coli ATCC 25922, and Pseudomonas aeruginosa ATCC 27853). S. aureus was the most sensitive strain to the essential oil with the largest inhibition zone (25±1). Cultivated Mentha longifolia (L.) Hudson, subs. schimperi may be a valuable candidate for further studies for the development of antibiotics and food preservatives.