1,721,306 research outputs found
Plant Neurobiology, a Fascinating Perspective in the Field of Research on Plant Secondary Metabolites
Full text linkIn this Editorial, I comment on the exciting and original topic of plant neurobiology, focusing on natural products whose biosynthesis is shared by animal and plant organisms, i.e., indoleamines (melatonin and serotonin) and catecholamines (dopamine, norepinephrine and epinephrine)
Botany in molecular era: a modern science with ancient roots
Full text linkBotany—the study of plant life—is an ancient science.[...
Tryptophan-ethylester, the false (unveiled) melatonin isomer in red wine
Full text linkAmong the food plants, the presence of melatonin in grapes (Vitis vinifera L.) deserves particular attention because of the production of wine, an alcoholic beverage of economic relevance and with putative healthy effects. Furthermore, melatonin isomers have been detected in wine too. Recently, one of these isomers has been identified as tryptophan-ethylester, a compound with the same molecular weight of melatonin. In this Commentary, we briefly comment the source(s) of tryptophan-ethylester in wine and the putative nutritional role(s)
Abscisic acid is involved in chitosan-induced resistance to tobacco necrosis virus (TNV)
No full textChitosan (CHT) antiviral activity has been further investigated in the pathosystem Phaseolus vulgaris –tobacco necrosis virus (TNV). CHT application elicited both callose apposition and ABA accumulation in leaf tissues, at 12 and 24 h after treatment, respectively, and induced a high level of resistance against TNV. Besides, treatment with the ABA inhibitor nordihydroguaiaretic acid (NDGA), before CHT application, reduced both callose deposition and plant resistance to the virus, thus indicating the involvement of ABA in these processes. Exogenous application of ABA also induced a significant resistance to TNV, though this resistance was abolished by NDGA pre-treatment. These results, overall, indicate that the rise of ABA synthesis induced by chitosan plays an important role in enhancing callose deposition but the latter has only a partial effect on virus spreading, which must be constraint by other resistance mechanisms
Callose synthesis as a tool to screen chitosan efficacy in inducing plant resistance to pathogens
No full textAbstract -The effectiveness of chitosans with different molecular weights (MW 6-753 kD) to elicit callose synthesis in Phaseolus vulgaris was evaluated, and correlated with their capability in inducing resistance to tobacco necrosis virus (TNV). To rapidly screen the pattern and amount of callose apposition, leaf fragments were floated in a cell culture multi-wells dish, each well filled with a different chitosan dissolved at variable concentration (0.1-0.2%), Aniline blue staining, performed 12 h after treatment, showed that chitosans with MW of 76,120 and 139 kD were the most effective in inducing callose synthesis in comparison with those having lower or higher MW. Callose appositions were randomly scattered in the mesophyll tissues, forming a homogeneous network of bright fluorescent spots. TNV inoculation of chitosan-treated bean plants showed that the efficacy of chitosans as resistance elicitors positively correlated with their ability in inducing callose apposition, with the 76-kD one being the most effective, with a 95% reduction of viral lesions, Microscopic and ultrastructural alterations in leaf fragments floated on chitosan and inoculated with TNV indicated that the mechanism of induced resistance involves, besides callose, a network of hypersensitive-like reactions, elicited by the compound, that impair virus spreading
Bioactivity of Grapevine (Vitis vinifera L.) Chemicals and Products : Focus on Antioxidant Power
No full textCell death behind invisible symptoms, early diagnosis of ozone injury
No full textA simple histo-cytochemical method, combining Evans blue staining to assess cell death and in vivo 3,3′-diaminobenzidine uptake for H 2O2 localisation, has been used to evaluate O3 damages in leaf tissues of three Phaseolus vulgaris L. cultivars (Cannellino, BLF, Saxa) with different sensitivity to the pollutant. Bean plants were exposed to a single pulse of O3 (150 ± 10 mm3 m -3 × 3 h) and leaves were examined at different time-span after fumigation. Cannellino proved to be the most sensitive, showing chlorotic spots 2 h after fumigation and chlorotic lesions 24 h later. In BLF, necrotic spots appeared 4 h after fumigation and reddish necrotic lesions (bronzing) developed in further 24 h. Saxa remained symptomless up to 10 d of observation, thus appearing tolerant. The early appearance of symptoms in Cannellino correlated with H2O2 accumulation in leaf tissues and consequent extensive cell death, involving both palisade and spongy mesophyll. H 2O2 accumulation was observed also in BLF, though to a lesser extent and dead cells were rare at 2 h after fumigation. However, they increased in number 24 h later, forming small groups in the palisade mesophyll. These groups further enlarged in the next 24 h, again involving only palisade mesophyll. In Saxa leaves, H2O2 accumulation was found only in the epidermal cells, though the number of dead cells was very similar to BLF, at least up to 24 h after fumigation. However, in Saxa, dead cells have been always found singly scattered through the palisade mesophyll, or forming very small groups around substomatal cavity, thus remaining invisible at a macroscopic level
Grape phytochemicals: A bouquet of old and new nutraceuticals for human health
No full textHealth benefits associated with Mediterranean diets are due to the significantly large intake of functional plant foods and beverages, i.e., fruits, vegetables, cereals, legumes, nuts, wine, beer, and olive oil, containing a great array of bioactive phytochemicals or nutraceutical compounds. Therefore, the low risk of chronic diseases, such as coronary hearth disease and certain cancers, observed in some population groups, results from a diversified eating style, either in term of foods and food components. The paradigm of the relationship between the chemical diversity of a particular food and the array of its biological activities may be symbolized by grape. Despite the extensive knowledge about phenylpropanoids, principally polyphenols (stilbenes and anthocyanins) and condensed tannins (proanthocyanidins), in grape and wine, little it is known about the other compounds, such as tetrahydro-β-carbolines. Recently, it has been attached importance to the dietary indoleamines, melatonin, and serotonin, in different plant foods, including grape, thus further supporting the hypothesis that health benefits, associated with Mediterranean dietary style, are due to plant food chemical diversity
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