ActivitÈ antioxydante, antibactÈrienne et insecticide des huiles essentielles de Cymbopogon schoenanthus (L.) Spreng.

Abstract

Cymbopogon schoenanthus (L.) Spreng. known by its vernacular name "El Lamad", medicinal plant is used in traditional Algerian medicine to treat urinary tract infections, digestive disorders and rheumatism. The aim of the present study is to determine certain physicochemical characteristics of essential oils (EOs) and to evaluate their antioxidant, antibacterial and insecticidal activities. Extraction was carried out by hydrodistillation on a Clevenger-type apparatus with a yield of 2.46%. The study of antioxidant power was carried out in vitro by CAT, DPPH and RP tests, revealing that our plant's EOs present moderately low antioxidant activity. Evaluation of the antibacterial activity of EOs against six strains of pathogenic bacteria revealed average antibacterial activity against the Gram+ strains tested, in particular S. aureus (inhibition zone diameter = 13.16 mm), while Gram- strains showed low sensitivity with inhibition zones of less than 9.5 mm. The insecticidal activity of C. schoenanthus (L.) Spreng. EOs was also evaluated on Macrosiphoniella sp. by a direct contact test. The obtained results revealing good insecticidal activity with LC50 and TL50 of 0.142 µL/mL and 23.36 h, respectively.