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Linseed (Linum usitatissimum L.) is becoming more and more important in the health food market as a functional food, since its seeds and oil represent a rich source of bioactive compounds. Its chemical composition is strongly correlated with, and dependent on, genetic characteristics. The aim of this study was to evaluate the variation in seed yield, oil content, fatty acid composition and secondary metabolite profiles between a low-linolenic linseed variety, belonging to the Solin-type group (Solal), and a high-linolenic traditional one (Bethune), cultivated, both as spring crops, in open field conditions of Central Italy. The achieved results pointed out the different behavior of the two varieties in terms of growth cycle, oil content, and some important yield components, such as capsule number per plant and thousand seed weight. There were also significant differences in seed composition regarding total phenols, total flavonoids, antioxidant activities as well as in carotenoid, tocopherol, and tocotrienol profiles between the two varieties. In particular, Solal was characterized by the greatest contents of oil, phenols, flavonoids, &alpha, and &delta, tocotrienol, together with the highest antioxidant activity. Bethune, on the contrary, showed the highest amounts of carotenoids (lutein and &beta, carotene). These results indicate a clear effect of the genetic characteristics on the biosynthesis of these secondary metabolites and, consequently, on the related antioxidant activity. Our findings suggest that the mutation process, responsible for the selection of the low-linolenic cultivar, is able to modify the biosynthetic pathways of carotenoids and phenolics.

Pompia is a Citrus species belonging to Sardinian endemic biodiversity. Health benefits were attributed to its flavedo rind extracts and essential oils while the juice qualities have never been investigated. In this paper, the antioxidant, antimicrobial, and other biological properties of Pompia juice were studied. A combined LCMS/electrochemical/biological approach was used to clarify a still debated phylogeny of this species and to explain the role of its juice phenolic compounds. A closer phylogenetic relationship with lemon and citron, rather than oranges was suggested. Sensors-based electrochemical measures, together with LCMS qualitative and quantitative analyses, revealed a high contribution of ascorbic acid and phenolics with low redox potential, isorhamnetin 3-O-rutinoside, diosmin, and diosmetin 6,8-diglucoside, to antioxidant capacity. The biological assays demonstrated a marked effect of low concentration of Pompia juice against reactive oxygen species (ROS) starting from 50 &micro, g mL&minus, 1, and a moderate capacity to reduce ROS damages on cell membrane. Treatments with Pompia juice also resulted in a significant reduction (20%) of the metabolic activity of SW48 colon cancer cells. Lastly, MIC, MBC, and MBIC antimicrobial assays demonstrated that Pompia and lemon juices have inhibitory and antibiofilm effects against the pathogenic bacteria Pseudomonas aeruginosa, Streptococcus aureus, and Enterococcus faecalis.

The impaired activity of tyrosinase and laccase can provoke serious concerns in the life cycles of mammals, insects and microorganisms. Investigation of inhibitors of these two enzymes may lead to the discovery of whitening agents, medicinal products, anti-browning substances and compounds for controlling harmful insects and bacteria. A small collection of novel reversible tyrosinase and laccase inhibitors with a phenylpropanoid and hydroxylated biphenyl core was prepared using naturally occurring compounds and their activity was measured by spectrophotometric and electrochemical assays. Biosensors based on tyrosinase and laccase enzymes were constructed and used to detect the type of protein&ndash, ligand interaction and half maximal inhibitory concentration (IC50). Most of the inhibitors showed an IC50 in a range of 20&ndash, 423 nM for tyrosinase and 23&ndash, 2619 nM for laccase. Due to the safety concerns of conventional tyrosinase and laccase inhibitors, the viability of the new compounds was assayed on PC12 cells, four of which showed a viability of roughly 80% at 40 &micro, M. In silico studies on the crystal structure of laccase enzyme identified a hydroxylated biphenyl bearing a prenylated chain as the lead structure, which activated strong and effective interactions at the active site of the enzyme. These data were confirmed by in vivo experiments performed on the insect model Tenebrio molitur.