Anthocyanins extracted from the berries of Phillyrea latifolia L., Pistacia lentiscus L., and Rubia peregrina L., three evergreen shrubs widely distributed in the Mediterranean area, were examined for their antioxidant and anticancer activity. The P. lentiscus anthocyanins showed the highest H 2 O 2 and 1,1-diphenyl-2-picrylhydrazil radical scavenging effects, indicating that these compounds can be considered as an alternative source of natural antioxidants for food and pharmaceutical products. Here, we also report a novel function of anthocyanins: the induction of autophagy, a process of subcellular turnover involved in carcinogenesis. Autophagy was characterized by the up-regulation of eIF2A, an autophagy inducer, and down-regulation of mTOR and Bcl-2, two autophagy inhibitors. This led to the enhanced expression of LC3-II, an autophagosome marker in mammals, and monodansylcadaverine incorporation into autolysosomes. Anthocyanin-induced autophagy switched to apoptosis, as shown by the activation of Bax, cytochrome c and caspase 3, terminal deoxynucleotide transferase -mediated dUTP nick-end labeling -positive fragmented nuclei, and cells with sub-G 1 DNA content, which were prevented by z-VAD. Inhibition of autophagy by either 3-methyladenine or Atg5 small interfering RNA enhanced anthocyanintriggered apoptosis. This provided evidence that autophagy functions as a survival mechanism in liver cancer cells against anthocyanin-induced apoptosis and a rationale for the use of autophagy inhibitors in combination with dietary chemopreventive agents. [Mol Cancer Ther 2008;7(8):2476 -85]
Two different novolac resins, named Nov-I and Nov-II, containing an amount of unreacted cardanol of 35 wt % and 20 wt %, respectively, were synthesized by the condensation reaction of cardanol and paraformaldehyde using oxalic acid as catalyst. Cardanol is the main constituent of cashew nut shell liquid, a renewable natural resource. The cardanol-based novolacs were tested as curing agents of the diglycidyl ether of bisphenol A epoxy resin employing 2-ethyl-4-methyl-imidazole as catalyst and differential scanning calorimeter and thermogravimetric studies were performed to identify the final thermal properties of the cured resins. In addition, tensile tests were carried out to evaluate the mechanical properties of the epoxy resin cured with the novolacs, which showed to deserve consideration as effective epoxy curing agents.
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