ABSTRACT
The failure of the antioxidant scavenging system in advanced ripening stages, causing oxidative stress, is one of the most important factor of fruit decay. Production of rich antioxidant fruit could represent a way to delay fruit senescence and preserve its characteristics. We investigated the antioxidant metabolites (ascorbate, glutathione, tocopherols, and polyphenols) and enzymes (ascorbic peroxidases, peroxidases and polyphenol oxidases) involved in the antioxidant response in forty-three accessions of sweet cherry fruits from Campania region. Our results highlight accessions with high antioxidant metabolites contents but low enzymatic activities. These represent important factors in both pre- and post-harvest on the qualitative and nutritional characteristics of sweet cherry. Observed differences are probably due to endogenous characteristics making these accessions particularly interesting for breeding programs aimed to improve fruit quality and shelf-life and for addressing the cultivation of a specific characterized cultivar based on the intended use, fresh consumption or processed products.
Subject(s)
Prunus avium , Antioxidants , Ascorbic Acid , FruitABSTRACT
In this article, we reported the original data obtained by the study of metabolites and enzymes involved in sweet cherry antioxidant system. We measured hydrogen peroxide (H2O2) and malondialdehyde (MDA), which are indicator of oxidative stress. Moreover, we measured the concentration of reduced and oxidized ascorbate and glutathione that are involved in ROS detoxification together with phenolics, anthocyanins and tocopherols. Among antioxidant enzymes, we analyzed the activities of ascorbate peroxidase (APX; EC 1.11.1.11), and the soluble and bound forms of polyphenol oxidase (PPO; EC 1.10.3.1) and guaiacol peroxidase (POD; EC 1.11.1.7). The data reported in this paper are related to the research article "Metabolic characterization and antioxidant activity in sweet cherry (Prunus avium L.) Campania accessions", authored by Mirto et al. (2018) [1].
ABSTRACT
Durum wheat plants are extremely sensitive to drought and salinity during seedling and early development stages. Their responses to stresses have been extensively studied to provide new metabolic targets and improving the tolerance to adverse environments. Most of these studies have been performed in growth chambers under low light [300-350 µmol m-2 s-1 photosynthetically active radiation (PAR), LL]. However, in nature plants have to face frequent fluctuations of light intensities that often exceed their photosynthetic capacity (900-2000 µmol m-2 s-1 ). In this study we investigated the physiological and metabolic changes potentially involved in osmotic adjustment and antioxidant defense in durum wheat seedlings under high light (HL) and salinity. The combined application of the two stresses decreased the water potential and stomatal conductance without reducing the photosynthetic efficiency of the plants. Glycine betaine (GB) synthesis was inhibited, proline and glutamate content decreased, while γ-aminobutyric acid (GABA), amides and minor amino acids increased. The expression level and enzymatic activities of Δ1-pyrroline-5-carboxylate synthetase, asparagine synthetase and glutamate decarboxylase, as well as other enzymatic activities of nitrogen and carbon metabolism, were analyzed. Antioxidant enzymes and metabolites were also considered. The results showed that the complex interplay seen in durum wheat plants under salinity at LL was simplified: GB and antioxidants did not play a main role. On the contrary, the fine tuning of few specific primary metabolites (GABA, amides, minor amino acids and hexoses) remodeled metabolism and defense processes, playing a key role in the response to simultaneous stresses.
