SummaryTomato ( Lycopersicon esculentum Mill.) tissues were transformed with a grape ( Vitis vinifera L.) stilbene synthase cDNA, transcriptionally regulated by the cauliflower mosaic virus (CaMV ) 35S promoter. Transgenic plants accumulated new compounds, not present in either wild-type or vector-transformed plants. These were identified, by high-pressure liquid chromatography, as trans -resveratrol and trans -resveratrol-glucopyranoside. The amounts of trans -resveratrol and its piceid form were evaluated in the transgenic fruit.It was found that the content of the metabolite varied during fruit maturation to up to 53 µ g/g fresh weight of total trans -resveratrol at the red stage of ripening. This metabolite accumulation was possibly dependent on a combination of sufficiently high levels of stilbene synthase and the availability of substrates. With the aim of verifing the metabolic impairment, the amounts of chlorogenic acid and naringenin in both transgenic and wild-type ripening fruit were compared and no dramatic variation in the synthesis profile of the two metabolites was noted. To our knowledge, no data are available on the assessment of the effects of the expression of the StSy gene on other antioxidant compounds present in tomato fruit. To establish whether the presence of a novel antioxidant molecule affected the redox regulation in transgenic tomato fruit cells, the effect of resveratrol accumulation on the naturally present antioxidant pool was analysed. We showed that, in transgenic fruit which accumulate trans -resveratrol, there is an increase in the levels of ascorbate and glutathione, the soluble antioxidants of primary metabolism, as well as in the total antioxidant activity. Conversely, the content of tocopherol and lycopene, which are membrane-located antioxidants, is not affected. Consistent with the increased antioxidant properties, the lipid peroxidation was lower in transformed than in wild-type fruit.
Phenolic acid intake through the consumption of whole-wheat foods provides important health benefits associated with reduced risks of cardiovascular diseases and colon cancer. The genetic variation for phenolic acids was extensively studied in common wheat, but a comprehensive survey in tetraploid wheat is lacking. In this study we evaluated the genetic variability for individual and total phenolic acids concentration existing in a large collection of tetraploid wheat (Triticum turgidum L.). A 2-year evaluation was undertaken on the whole-meal flour of 111 genotypes belonging to seven T. turgidum subspecies including cultivars, landraces and wild accessions. Durum cultivars [T. turgidum subsp. durum (Desf.) MacKey], had the highest average concentration of total phenolic acids (828.7 μg g−1 dm in 2012; 834.5 μg g−1 dm in 2013) with amounts varying from 550.9 μg g−1 dm to 1701.2 μg g−1 dm, indicating a variation of greater than threefold fold. The lowest concentration of phenolic acids was found in T. turgidum subsp. dicoccum (Schrank ex Schübler) Thell. Rivet wheat (T. turgidum L. subsp. turgidum) had phenolic acid concentrations similar to those in durum, but less variation was noted among the accessions. On the other hand, the accessions of the four remaining subspecies showed lower phenolic acid concentrations and variation among the accessions as compared to durum. A total of six phenolic acids were identified across the wheat genotypes. The effects of genotype, year and year × genotype were estimated by ANOVA and resulted significant for all phenolic acids. The ratio of genotypic variance to total variance suggested the possibility of improving phenolic acid content in elite wheat germplasm through appropriate breeding programs. Moreover, significant correlations between phenolic acids and other quality characteristics of the grain were detected
SummaryResveratrol, a plant phenolic compound, is found in grapes and red wine, but is not widely distributed in other common food sources. The pathway for resveratrol biosynthesis is well characterized. Metabolic engineering of this compound has been achieved in tomato plants capability and ascorbate content in transformed fruits were also evaluated, and a significant increase in both was found in the LoxS and 35SS lines. These results could explain the higher capability of transgenic fruits to counteract the pro-inflammatory effects of phorbol ester in monocyte-macrophages via the inhibition of induced cyclo-oxygenase-2 enzyme.
Abstract:The carrot (Daucus carota L.) is an important vegetable source of bioactive compounds in the human diet. In the Apulia region (Southern Italy), local farmers have domesticated colored landraces of carrots over the years, strictly related to local cults and traditions. Amongst these, an important landrace is the carrot of Saint Ippazio or the Tiggiano carrot. In the present study, we evaluated the content of carotenoids, anthocyanins, phenolic acids, sugars, organic acids, and antioxidant activity in Tiggiano carrots. Our results indicated that yellow-purple carrots have the highest levels of bioactive compounds, together with the highest antioxidant capacity compared to the yellow and cultivated orange varieties. These data point out the nutritional value of purple Tiggiano carrots and may contribute to the valorization of this typical landrace.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.