Chemical Analysis of Volatile Constituents of Pulicaria Mauritanica Isolated by Hydrodistillation and Headspace Solid-phase Micro-extraction Techniques. Antimicrobial Activity of its Essential Oil

The objective of this study is the comparative chemical analysis of essential oil (EO) obtained by hydrodistillation (HD) isolated from Pulicaria mauritanica using Gas Chromatography-Retention Indices (GC-RI) and GC-Mass Spectrometry (GC-MS). The volatile fraction (VF) was detected by headspace solid-phase micro-extraction (HS-SPME) The antimicrobial activity of P. mauritanica EO against three bacterial strains referenced by the ATCC (American Type Culture Collection): Escherichia coli (ATCC 25922), Staphylococcus aureus (ATCC 25923) and Pseudomonas aeruginosa (ATCC 27853) and a one yeast Candida albicans was also evaluated in vitro using the paper disc diffusion and minimum inhibitory concentration (MIC) assays. The chromatographic profile indicates the quantitative and semi qualitative differences between the chemical compositions of both analyzed samples. The antimicrobial activity tested by two methods indicates that this EO is more effective against three strains tested except P. aeruginosa which is the most resistant strain. Indeed, the results of the report MBC (Minimum Bactericidal Concentration)/MIC show that the EO has a bactericidal effect on S. aureus and a bacteriostatic and fungistatic effect on E. coli and C. albicans, respectively. P. mauritanica EO seems to be a promising source of natural products with potential antimicrobial activity.