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The genotyping of cultivated varieties using molecular markers is a crucial aim of modern plant breeding programmes, germplasm collection management and product traceability. Methods for DNA extraction from olive oil are now available, and the DNA extracted is suitable for PCR applications. The aim of this work was to identify simple and reliable PCR markers useful for cultivar identification and oil traceability. We chose to analyse 13 cultivars and one feral accession of Olea europaea for polymorphism in the intergenic spacer of chloroplast DNA (cpDNA). The spacer analysed in this work showed a pattern of variation that was sufficient to discriminate four out of the 13 cultivars analysed. We propose an identification protocol for these cultivars based on the amplification and subsequent sequencing of the chloroplast trnT-trnD intergenic spacer. The ability to design primers pairs capable of amplifying very small fragments makes these markers useful in traceability protocols, even where the quality, yield and size of the DNA recovered from the oil may be very low. [ABSTRACT FROM AUTHOR]

Background: Oxidative stress induced by hyperglycemia is a key factor in the pathogenesis of diabetic complications, such as neuropathy. Recently, green tea catechins have received much attention, as they can facilitate a number of antioxidative mechanisms and improve glycemic control.Objective: The aim of this study was to investigate the cytoprotective effects of (-)-epigallocatechin-3-gallate (EGCG) against oxidative stress damage in a cell line of rat neurons. The role of heme oxygenase 1 (HO-1) induction by EGCG and the transcriptional mechanisms involved were also evaluated.Methods: Immortalized rat neurons (H 19-7) were exposed to various concentrations of EGCG (10-200 microM). After treatments (6 or 24 hours), cells were harvested for the determination of heme oxygenase activity, mRNA levels, and protein expression. Nuclear levels of Nrf2, a transcriptional factor involved in HO-1 activation, were also measured. Neurons were pretreated for 12 hours with EGCG 50 microM or EGCG 50 microM + zinc protoporphyrin IX 10 microM and then exposed for 2 hours to 50 mmicro/mL glucose-oxidase before cell viability was determined.Results: In cultured neurons, elevated expression of HO-1 mRNA and protein were detected after 6 hours of incubation with 25-100 microM EGCG, and its induction relates with the activation of Nrf2. Interestingly, pre-incubation (12 hours) with EGCG 50 microM resulted in an enhanced cellular resistance to glucose oxidase-mediated oxidative damage; this cytoprotective effect was considerably attenuated by zinc protoporphyrin IX, an inhibitor of heme oxygenase activity.Conclusions: In this study, we demonstrated that EGCG, the major green tea catechin, induced HO-1 expression in cultured neurons, possibly by activation of the transcription factor Nrf2, and by this mechanism was able to protect against oxidative stress-induced cell death. [ABSTRACT FROM AUTHOR]