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The concentrations of the volatile components of the white truffle (Tuber magnaturn Pico), determined by purge and trap methods, showed the impact role of 2,4-dithiapentane. The degradation of the aroma showed great dependence on the storage conditions. At 0°C amyl alcohols are released, while at room temperature the conversion of 2,4-dithiapentane into dimethyl disulphide becomes the most relevant alteration of the flavour.

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Hypericum androsaemum, also known as Tutsan, is a small evergreen shrub common in the Mediterranean basin where it is traditionally used as diuretic and hepatoprotective herbal drug. This plant possesses the peculiarity to produce fleshy and berry-like fruits that ripen from red to shiny black. In the present work, the chemical constituents of methanolic extracts and infusions of red and black fruits were analyzed by HPLC, and correlated with their antioxidant properties which were evaluated by the DPPH, β-Carotene/linoleic acid, and hypochlorous acid tests. In addition, the red pigment of the fruit was isolated by column chromatography and structurally elucidated by NMR. Results showed that H. androsaemum fruits contain high amounts of shikimic and chlorogenic acids, while their color was given by a tetraoxygenated-type xanthone, reported for the first time in Hypericum species. The red berries infusion gave the highest content of total phenolic compounds, DPPH, and hypochlorous acid scavenging activity, and β-carotene bleaching. Cytotoxicity of the berries extracts on three human tumor cell lines (malignant melanoma, breast adenocarcinoma, and colon carcinoma) was evaluated by MTT assay, and relevant inhibition on colon carcinoma cells (IC50 value of 8.4 μg/mL) was found. Finally, the effects of red berries extract on the immune system were evaluated by peripheral blood mononuclear cell (PBMC) proliferation assay that revealed a strong stimulation on lymphocytes at low doses (0.4–6 μg/mL).

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The origin and taxonomy of Citrus monstruosa (Rutaceae) are currently unknown and thus a nontargeted metabolomic analysis on the flavedo volatiles was performed. Headspace solid-phase micro extraction coupled with gas chromatography analysis was applied to eight Citrus spp. including Citrus monstruosa, and the chemical composition of the volatile organic compounds (VOC) was analyzed to give a chemical comparison between different Citrus species. Forty-four metabolites were detected across the species: several monoterpenes were found in all Citrus spp. and among them limonene comes first in all Citrus spp. ranging from 96.7 to 66.7%. Conversely, some molecules were found to be specific for only a few of the samples. The classical univariate evaluation of the VOC data is unlikely to give objective data for the cultivar classification; a multivariate approach, principal component analysis, is an easy to use, powerful tool. Therefore, a chemometric comparison between chromatographic data of all Citrus spp. was performed with the aim of understanding the role of VOC in the discrimination of the eight studied cultivars.