Chemical composition and antibacterial activity of the essential oils from Launaea resedifolia L

Abstract

BackgroundSeveral species of the genus Launaea are used in folk medicine such as in bitter stomachic, skin diseases, and reported to have antitumor, insecticide, and cytotoxic activities. The antimicrobial activities of coumarin constituents and the neuropharmacological properties have been investigated as well. In this study, the chemical composition of essential oils from Launaea resedifolia L. has been identified using the ordinary GC-MS technique to reveal the presence of 19 compounds dominated by dioctyl phthalate. Moreover, the antibacterial activity of the crude oil has been carried out using disk diffusion method against seven bacteria strains.ResultsNineteen compounds of essential oil of L. resedifolia L. were identified, representing 86.68% of the total oil. The compounds were identified by spectral comparison to be mainly esters, alcohols, ketones, and terpenes. The principal constituents are dioctyl phthalate (39.84%), Decanoic acid, decyl ester (12.09%), 11-Octadecenal (11.24%), and Eucalyptol (07.31%), while others were present in relatively small amounts. As far as antibacterial essays are concerned, it was found that the oils are active against most of the tested bacterial strains.ConclusionA major constituent in visible parts was Dioctyl phthalate (39.84%) and the yield of essential oils was 0.9%. These extracts reveal in vitro antibacterial activity on the studied bacterial, confirmed by the inhibition zone diameter ranging from 11 to 37 mm and a MIC value between 0.09 and 0.69 depending on the microorganism being tested.

Chemical composition and antibacterial activity of essential oil of Launaea lanifera Pau grown in Algerian arid steppes

“…The essential oil yield obtained in the current study is very low compared to those obtained from L. resedifolia (L. fragilis), 0.9% [18], and L. arborescens, 0.07% [17], growing in the Algerian Sahara. A yield of 0.035% was obtained from L. nudicaulis grown in Oman [20].…”

“…Regarding the antibacterial activity, important bacterial activity has been reported for Launaea residifolia essential oil, which is of the same genus as L. lanifera, against some bacterial strains, including those used in the current analysis (S. aureus, P. aeruginosa and E. coli) [18] . This result may be due to the complete different chemical composition of the two oils.…”

“…However, most of these investigations were focused on crude solvent extracts [10][11][12][13][14][15][16]. To the best of our knowledge, only three researches studied the essential oils of the Algerian Saharan species: L. arborescens [17] , Launaea resedifolia [L. resedifolia (L. fragilis)] [18] and L. nudicaulis [19]. Moreover, another research work about the essential oil composition of L. nudicaulis grown in Oman has also been published [20].…”

Essential oils and hydrophilic extracts from the leaves and flowers of Succisa pratensis Moench. and their biological activity

“…Thymol, which was determined at more than 1% in the oil from the leaves of S. pratensis , is known for strong antimicrobial properties . Other compounds showing antimicrobial activity, such as butyl‐octyl ester 1,2‐benzenedicarboxylic acid, 2‐Hexyl‐1‐octanol, were found in the essential oils, too . 2‐Hexyl‐1‐octanol was one of the main components of the essential oil from Barleria lupulina with microbiological activity against Bacillus pumilus and S. aureus .…”

“…[18] Other compounds showing antimicrobial activity, such as butyl-octyl ester 1,2-benzenedicarboxylic acid, 2-Hexyl-1-octanol, were found in the essential oils, too. [19][20][21] 2-Hexyl-1-octanol was one of the main components of the essential oil from Barleria lupulina with microbiological activity against Bacillus pumilus and S. aureus. [21] The compounds identified in predominant quantities in the oils were also found in the essential oil from Laminaria japonica, which was characterized by great activity against Bacillus cereus, Eschericha coli, S. aureus and by great antioxidant activity in the test with the DPPH radical (1,1-diphenyl-2-picrylhydrazyl) and ABTS (2,2″-azinobis (3-ethylbenzotiazoline-6-sulphonic acid).…”