Antimicrobial activities of essential oil and hexane extract of Florence fennel [Foeniculum vulgare var. azoricum (Mill.) Thell.] against foodborne microorganisms.

The objective of this study was to determine the chemical compositions of the essential oil and hexane extract isolated from the inflorescence, leaf stems, and aerial parts of Florence fennel and the antimicrobial activities of the essential oil, hexane extract, and their major component, anethole, against a large variety of foodborne microorganisms. Gas chromatography and gas chromatography-mass spectrometry analysis showed that the essential oils obtained from inflorescence, leaf stems, and whole aerial parts contained (E)-anethole (59.28-71.69%), limonene (8.30-10.73%), apiole (trace to 9.23%), beta-fenchyl acetate (3.02-4.80%), and perillene (2.16-3.29%) as the main components. Likewise, the hexane extract of the plant sample exhibited a similar chemical composition, and it contained (E)-anethole (53.00%), limonene (27.16%), gamma-terpinene (4.09%), and perillene (3.78%). However, the hexane extract also contained less volatile components such as n-hexadecanoic acid (1.62%), methyl palmitate (1.17%), and linoleic acid (1.15%). The in vitro antimicrobial assays showed that the essential oil, anethole, and hexane extract were effective against most of the foodborne pathogenic, saprophytic, probiotic, and mycotoxigenic microorganisms tested. The results of the present study revealed that (E)-anethole, the main component of Florence fennel essential oil, is responsible for the antimicrobial activity and that the essential oils as well as the hexane extract can be used as a food preservative. This study is the first report showing the antimicrobial activities of essential oil and hexane extract of Florence fennel against probiotic bacteria.

Chemical composition of hydrodistilled essential oil of Artemisia incana (L.) Druce and antimicrobial activity against foodborne microorganisms.

The oil obtained by hydrodistillation from the aerial parts of Artemisia incana (L.) Druce from Turkey was analyzed by GC and GC/MS. Sixty-three compounds were characterized, representing 97.2% of the total components detected, and camphor (19.0%), borneol (18.9%), 1,8-cineole (14.5%), bornyl acetate (7.8%), camphene (4.9%), and alpha-thujone (4.8%) were identified as predominant components. The essential oil was also tested for its antimicrobial activity against 44 different foodborne microorganisms, including 26 bacteria, 15 fungi, and 3 yeast species. The essential oil of A. incana exhibited considerable inhibitory effects against all bacteria, fungi, and yeast species tested. However, the oil showed lower inhibitory activity against the tested bacteria than the reference antibiotics.

Antioxidant properties and total phenolic content of eight Salvia species from Turkey.

Methanolic extracts of eight Salvia species, namely S. aethiopis, S. candidissima, S. limbata, S. microstegia, S. nemorosa, S. pachystachys, S. verticillata, and S. virgata, sampled from Eastern Anatolia in Turkey, were screened for their possible antioxidant activities by two complementary test systems, namely DPPH free radical scavenging and beta-carotene/linoleic acid. Total phenolic content of the extracts of Salvia species were performed Folin-Ciocalteu reagent and gallic acid used as standard. A wide variation has been observed among species in terms of antioxidant activity and total phenolic content. In both DPPH and beta-carotene system, the most active plant was Salvia verticillata with a value of IC50=18.3 microg/ml and 75.8%, respectively. This species also has the highest total phenolic content (167.1 mgGAE/g DW). The total amount of phenolics was between 50.3 to 167.1 mgGAE/g DW among species. A positive linear correlation was observed between total phenolic content and antioxidant activity of the extracts. The results suggest that the extract of Salvia species, notably Salvia verticillata with the highest antioxidant activity, can be used as natural antioxidants in the food industry.

Antioxidant Properties and Total Phenolic Content of Eight Salvia Species from Turkey

Methanolic extracts of eight Salvia species, namely S. aethiopis, S. candidissima, S. limbata, S. microstegia, S. nemorosa, S. pachystachys, S. verticillata, and S. virgata, sampled from Eastern Anatolia in Turkey, were screened for their possible antioxidant activities by two complementary test systems, namely DPPH free radical scavenging and b-carotene/linoleic acid. Total phenolic content of the extracts of Salvia species were performed Folin-Ciocalteu reagent and gallic acid used as standard. A wide variation has been observed among species in terms of antioxidant activity and total phenolic content. In both DPPH and b-carotene system, the most active plant was Salvia verticillata with a value of IC50=18.3 μg/ml and 75.8 percent, respectively. This specie also has the highest total phenolic content (167.1 mgGAE/g DW). The total amount of phenolics was between 50.3 to 167.1 mg GAE/g DW among species. A positive linear correlation was observed between total phenolic content and antioxidant activity of the extracts. The results suggest that the extract of Salvia species, notably Salvia verticillata with the highest antioxidant activity, can be used as natural antioxidants in the food industry.