ABSTRACT
Apiaceae is a large plant family; it comprises about 60 annual and biannual species mostly distributed in Europe, Africa, West Asia, and Australia. The Daucus genus is one of the most common genera of this family in which Daucus syrticus [DS] is a common member, growing mainly in the Sirt region [Libya]. It is locally known as wild carrot. This study aims to investigate volatile oils, lipid constitutes, and the antimicrobial activity of DS extracts. The herb of DS was collected from Wadi Telal, Sirt region [Libya], during January and April 2011. About 250 g of different parts from fresh plant material [aerial parts, roots, and seeds] of DS were subjected to hydrodistillation. Extraction of lipid constituents was carried out as follows: About 1500 g of dried powdered plant material of DS were extracted with petroleum ether in a soxhlet. The antimicrobial activity was determined using the disk diffusion method, and the inhibition zone [IZ] was measured for each extract under study against Escherichia coli, Bacillus subtilis, Aspergillus niger, and Candida albicans. Results of Gas chromatography/Mass spectrometry GC/MS analyses of the volatile oils of the aerial parts [January and April collections] proved that they contain a mixture of 47 and 33 compounds, respectively, whereas the roots [April and July] were found to contain a mixture of 32 and 20 compounds, respectively. In addition, the seeds [July] were found to contain 18 compounds, with beta-asarone [26.23%] as the main compound. Investigation of the lipid fraction of the herb revealed the presence of a mixture of fatty alcohols; the major contents of the unsaponifiable fraction were identified as a series of n-alkanes C[8]-C[28] [84.85%], four steroidal compounds, triterpene, and a mixture of fatty acid methyl esters consisting of eight different acids. The antimicrobial evaluation of DS extracts exhibited different IZ values against the tested microorganisms. The main constituents of the different volatile oils of the aerial parts, the roots, and the seeds were identified. The fraction of total fatty acid had the highest activity against E. coli [IZ = 2.7, minimum inhibitory concentration = 250 mg/ml]
ABSTRACT
Brassicaceae is a large plant family; it includes vegetable crops, weeds, garden and wild flowers. Erucaria pinnata is one of the most common species of this family, which mainly growing in Sirt region and locally known as Saleekh. This study aim to isolate, identify lipid constituents and isothiocyanates and also to evaluate the potency of different extracts of Erucaria pinnata as antimicrobial agents. The plant was collected from Sirt region in February 2008 during the flowering stage. The aerial parts of the plant [leaves, flowers and branches] were air dried and ground until they become as a fine powder. Mass spectrophotometer GC/MS Jcol 500 Mass spectroscopy 70 cV. Agilent Technologies 6890 N Network GC System. Gas liquid chromatography Hewlett Packard HP 6890 series. Isolation of Lipids: one kg of air dried powdered plant of Erucaria pinnata was extracted with n-hexane in a Soxhlet for 24 hours till exhaustion. Extraction of the total glucosinolates and preparation of total isothiocyanates. Antimicrobial activity:the antimicrobial activity was determined using the sensitivity disk diffusion method of Kirby-Bauer and determination of inhibitory zone [I.Z.]. Used microorganisms: Staphylococcus aureus, Bacillus subtilis, Escherichia coli, Mycobacterium phleis, Enterobacter cloacae, Aspergillus niger and Candida albicam. The GLC analysis of E. pinnata fatty acid methyl esters revealed the presence of six acids in which palmitic acid is the main one [65.10%]. While the GLC analysis of the unsaponifiable matters revealed the presence of a series of long chain hydrocarbons with n-C[20] and n-C[29] are the main ones [13.45% and 12.88% respectively]. Using GC/MS analysis for the obtained ITC after enzymatic hydrolysis of the total glucosinolates, were identified as 8-methylsulfinyl octyl ITC, 4-methylsulfinyl-3-butenyl ITC, 2-phenylethyl ITC and 3-methylthio-2-propenyl ITC. The results proved that, only total ITCs, glucosinolates and butanol extract exhibited different inhibition effects against all tested organisms. Ethyl acetate extract exhibited different inhibition effects against only tested Gram +vc bacteria, while, the acetone insoluble fraction and unsaponifiable matters showed no inhibition effects by any means against all tested microorganisms at all concentrations used. The lipid constituents [fatty acids and unsaponifiable matters] of Erucaria puinnata were identified, also four isothiocyanatcs were isolated and identified using GC/MS. The isolated isothiocyanates is more potent as antimicrobial than precursor glucosinolates