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The authenticity of fruit fl avours in foods and beverages is of great importance for the producers of jams, ice creams, soft drinks, yogurt, etc. Regulations regarding the authenticity of fl avours in foods and beverages will help consumers choose the foods best suitable for them. In order to enhance this goal, we have used headspace-solid phase microextraction stereoselective gas chromatography-mass spectrometry (HS-SPME stereoselective GC-MS) to determine the enantiomeric ratios of chiral fl avour and fragrance indicators present in the raw materials and in the products. γ-Decalactone in peach, nectarine, strawberry, passion fruit and apricot, as well as (E)-α-ionone in raspberry and linalool and linalyl acetate in bergamot, were used as indicators in stereoselective analysis of commercial foods and beverages. In the fresh fruit aromas only one enantiomer was predominant or enantiomerically pure. In many commercial fruit products we detected racemic mixtures of the above-mentioned chiral fl avour compounds. The results suggest that HS-SPME stereoselective GC-MS could be a useful tool for diff erentiating natural fl avour compounds from synthetic ingredients in quality control of foods and beverages.

Fusarium root and stem rot caused by the fungus Fusarium oxysporum f. sp. radiciscucumerinum is a major disease in greenhouse cucumbers. Over the past decade, the disease has been documented in melon greenhouses in Greece, and recently it has been sporadically recorded in greenhouse melons in Israel. Variations in disease response were found among 41 melon accessions artificially inoculated with the pathogen: 10 accessions were highly susceptible (90-100% mortality), 23 exhibited an intermediate response (20-86%) and eight were resistant (0-4%). Two melon accessions -HEM (highly resistant) and TAD (partially Accepted ArticleThis article is protected by copyright. All rights reserved. resistant) -were crossed with the susceptible accession DUL. The responses of the three accessions and F 1 crosses between the resistant and susceptible parents were evaluated. HEM contributed higher resistance to the F 1 hybrid than TAD. Roots of susceptible and resistant accessions were 100 and 79% colonized, respectively, following artificial inoculation.However, only susceptible plants showed colonization of the upper plant tissues. Microscopic evaluation of cross sections taken from the crown region of the susceptible DUL revealed profuse fungal growth in the intercellular spaces of the parenchyma and in xylem vessels. In the resistant cultivar HEM, very little fungal growth was detected in the intercellular spaces of the parenchyma, and none in the xylem or any other vascular tissue. Finding resistant accessions may create an opportunity to study the genetics of resistance inheritance and to develop molecular markers that will facilitate breeding resistant melon cultivars.

Oxidative stress has been implicated in pathologic processes associated with neurodegenerative diseases. Astrocytes, the most abundant glial cell type in the brain, protect neurons from reactive oxygen species (ROS), and any damage to them will affect neuronal survival. This study compares the ability of essential oils prepared from different herbs and spices to protect cultured primary brain astrocytes from H2O2-induced death. The results show that the essential oil of Salvia fruticosa (Sf) among the tested essential oils demonstrated remarkable protective activity. The protective effect of Sf could be attributed to alpha-humulene and alpha-pinene. Following incubation, alpha-humulene and trans-beta-caryophyllene could be found in the cytosol of astrocytes. It is proposed that Sf, by attenuating H2O2-induced cell death, might be used as a functional food or may be offered as a means of therapy in the treatment of neurodegenerative diseases.

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