CHEMICAL ANALYSIS, ANTIOXIDANT AND ANTIMICROBIAL ACTIVITY OF THREE GREEK CUCUMBER (CUCUMIS SATIVUS) CULTIVARS

The volatiles of three Greek cucumber cultivars (Cucumis sativus L.) were analyzed by gas chromatography and mass spectrometric detection. Twenty-one components were identified. The major components from each sample were found to be: sample A, Z-6-nonenol (61.54%), E-2-nonenal (6.98%), sample B, E, Z-2,6-nonadienal (47.08%), E-2-nonenal (17.39%), Z-3-nonenol (14.79%), 3-nonenal (7.32%), sample C, pentadecanal (43.47%), 9,12,15-octadecatrienal (14.52%) and 9,17-octadecadienal (12.33%). Additionally, several constituents have been isolated and identified from the dichloromethane, and methanolic extract of fruits from sample B. It was found that cucumber contained a high concentration of L-(+) lactic acid which, as a member of a-hydroxy acids (AHAs) with established use in cosmetology, could explain the traditional use of cucumber in skin treatment. Finally, the in vitro antioxidant (DPPH [1,1-diphenyl-2-picrylhydrazyl] assay) and antimicrobial activity of the extracts and/or volatiles from all studied samples against six bacteria and three fungi were also assayed and reported.