Ariel Vicente
Universidad Nacional de La Plata, Agroindustrias, Faculty Member
- I am a Full Professor at the National Univ of La Plata, Argentina and Principal researcher at CONICET. My main work... moreI am a Full Professor at the National Univ of La Plata, Argentina and Principal researcher at CONICET. My main work is oriented towards reducing fotos wastage and postharvest losses.edit
For the fruit postharvest physiologist, discussions of cell wall metabolism initially bring to mind the processes associated with the fruit softening that occurs during ripening. Fruit softening traditionally has been equated to the... more
For the fruit postharvest physiologist, discussions of cell wall metabolism initially bring to mind the processes associated with the fruit softening that occurs during ripening. Fruit softening traditionally has been equated to the series of apoplast-localized events that lead to textural changes, which are desired by most consumers. Among these events, the enzyme-catalyzed breakdown and solubilization of cell wall polysaccharides are considered to be crucial in most fruit. The goal of this paper is to help us to see fruit softening in terms of a series of mechanistically connected wall metabolism processes that ends with the familiar texture changes, but which may influence a good deal more of the developmental and metabolism transitions that occur as a fruit ripens. Yin and Yang are terms that describe the apparently opposing, but occasionally complementary, sides of the same entity. The postharvest biologist certainly must apply this perspective to his/her view of the ripening fruit's cell wall metabolism. In general, the most costly fruit postharvest management problems are associated with poorly controlled ripening (the softening aspects, in particular) and losses to pathogens. Our work with tomato fruit demonstrates a Yin/Yang-like connection between (1) the wall metabolism events that control ripening and (2) the processes that convert an unripe, pathogen-resistant tomato to a fully ripe, pathogen-susceptible fruit. A biologist who studies the evolution of angiosperms would most likely see the ripening fruit's softening and increasing pathogen susceptibility as behaviors that contribute to seed dispersal and the eventual success of well-adapted species. A longer-term goal of this research is to understand the genetic basis of this linkage and then sever it, thus enabling the delivery of ripe and pathogen-free fruit to consumers.
Noble rot results from exceptional infections of ripe grape (Vitis vinifera) berries by Botrytis cinerea. Unlike bunch rot, noble rot promotes favorable changes in grape berries and the accumulation of secondary metabolites that enhance... more
Noble rot results from exceptional infections of ripe grape (Vitis vinifera) berries by Botrytis cinerea. Unlike bunch rot, noble rot promotes favorable changes in grape berries and the accumulation of secondary metabolites that enhance wine grape composition. Noble rot-infected berries of cv Sémillon, a white-skinned variety, were collected over 3 years from a commercial vineyard at the same time that fruit were harvested for botrytized wine production. Using an integrated transcriptomics and metabolomics approach, we demonstrate that noble rot alters the metabolism of cv Sémillon berries by inducing biotic and abiotic stress responses as well as ripening processes. During noble rot, B. cinerea induced the expression of key regulators of ripening-associated pathways, some of which are distinctive to the normal ripening of red-skinned cultivars. Enhancement of phenylpropanoid metabolism, characterized by a restricted flux in white-skinned berries, was a common outcome of noble rot and red-skinned berry ripening. Transcript and metabolite analyses together with enzymatic assays determined that the biosynthesis of anthocyanins is a consistent hallmark of noble rot in cv Sémillon berries. The biosynthesis of terpenes and fatty acid aroma precursors also increased during noble rot. We finally characterized the impact of noble rot in botrytized wines. Altogether, the results of this work demonstrated that noble rot causes a major reprogramming of berry development and metabolism. This desirable interaction between a fruit and a fungus stimulates pathways otherwise inactive in white-skinned berries, leading to a greater accumulation of compounds involved in the unique flavor and aroma of botrytized wines.
The stability of vegetable antioxidants in response to processing and cooking treatments may be affected by the variety. However, the information available in the literature is very limited. In this work we determined the influence of the... more
The stability of vegetable antioxidants in response to processing and cooking treatments may be affected by the variety. However, the information available in the literature is very limited. In this work we determined the influence of the eggplant variety (white e cv 'Cloud Nine' and purple e cv 'Lucia') on pulp chlorogenic acid content (5-O-caffeoyl-quinic acid; CQA) and antioxidant capacity (AC) in response to common pre-processing (cutting, salting or blanching), processing (air-vacuum-solar-and freeze-drying, slow-and fast-freezing) and cooking methods (microwaving, baking, grilling, steaming, boiling or pressure cooking). Fresh purple 'Lucia' eggplants showed higher AC and CQA content (16%) than white 'Cloud Nine' fruit. Fruit pre-processing caused significant losses of AC, with the effect being higher in the purple cultivar. Hot air-and sun-drying almost depleted CQA in both cultivars. In contrast, white eggplants retained higher AC upon freezing and microwaving. Wet cooking methods (boiling and pressure cooking) markedly increased fruit AC indicating that these preparation procedures improved antioxidant extractability. The eggplant cultivar has a major influence in antioxidant retention during processing and cooking; the white variety 'Cloud Nine' proved in general, more suitable for processing in terms of antioxidant retention than the purple 'Lucia' genotype.
Fruit ripening is characterized by processes that modify texture and flavor but also by a dramatic increase in susceptibility to necrotrophic pathogens, such as Botrytis cinerea. Disassembly of the major structural polysaccharides of the... more
Fruit ripening is characterized by processes that modify texture and flavor but also by a dramatic increase in susceptibility to necrotrophic pathogens, such as Botrytis cinerea. Disassembly of the major structural polysaccharides of the cell wall (CW) is a significant process associated with ripening and contributes to fruit softening. In tomato, polygalacturonase (PG) and expansin (Exp) are among the CW proteins that cooperatively participate in ripening-associated CW disassembly. To determine whether endogenous CW disassembly influences the ripening-regulated increase in necrotropic pathogen susceptibility, B. cinerea susceptibility was assessed in transgenic fruit with suppressed polygalacturonase (LePG) and expansin (LeExp1) expression. Suppression of either LePG or LeExp1 alone did not reduce susceptibility but simultaneous suppression of both dramatically reduced the susceptibility of ripening fruit to B. cinerea, as measured by fungal biomass accumulation and by macerating l...
Research Interests:
Research Interests: Metabolism, Heat Treatment, Food Preservation, Peroxidase, Postharvest biology, and 14 morePotassium, Strawberry, Superoxide Dismutase, Postharvest Biology and Technology, Hydrogen Peroxide, Ascorbic Acid, Warehousing, Peroxidases, Postharvest, POD, Antioxidant Capacity, Oxidative Metabolism, Ascorbate Peroxidase, and Respiration Rate
Anthocyanins are water-soluble pigments responsible for blue, purple and red color of many fruits such as berries, grapes, cherries, pomegranates, plums, apples, and some citrus and tropical fruits. Anthocyanins have ecological functions... more
Anthocyanins are water-soluble pigments responsible for blue, purple and red color of many fruits such as berries, grapes, cherries, pomegranates, plums, apples, and some citrus and tropical fruits. Anthocyanins have ecological functions as attractants to pollinators and/or predators, provide protection against excessive radiation, act as antimicrobials and most promptly they have high antioxidant potency. Chemically, anthocyanins belong to a parent class of molecules, the flavonoids, and are glycosydes containing a sugar moiety and an aglycone unit (the anthocyanidin) which is derived from the flavylium ion. More than 635 different anthocyanins and 23 anthocyanidins by now have been already described. The structural differences among anthocyanins are related to the number of hydroxyl groups in the anthocyanidin skeleton, the position and the number of bonded sugar residues as well as by the aliphatic or aromatic carboxylates bonded to them. The distribution of the six most common a...
Cryptochromes are blue light photoreceptors found in plants, bacteria, and animals. In Arabidopsis, cryptochrome 2 (cry2) is involved primarily in the control of flowering time and in photomorphogenesis under low-fluence light. No data on... more
Cryptochromes are blue light photoreceptors found in plants, bacteria, and animals. In Arabidopsis, cryptochrome 2 (cry2) is involved primarily in the control of flowering time and in photomorphogenesis under low-fluence light. No data on the function of cry2 are ...
Research Interests: Microbiology, Phytochemistry, Kinetics, Plant Biology, Medical Microbiology, and 27 moreZingiberales, Plant Science, Signal Transduction, Biological Sciences, Plant Physiology, P-glycoprotein, Temperature, Activation Energy, Sodium Dodecyl Sulfate-Polyacrylamide Gel Electrophoresis, Ion Exchange Chromatography, Enzyme, CHEMICAL SCIENCES, Fermentation, Psidium guajava, Specific Activity, ACTA, Substrate Specificity, Enzyme activity, Plant species, Metal ion, CARBOHYDRATES, Molecular weight, Plant Cell Wall, Ascomycota, Plant Disease Resistance, Polygalacturonase, and Submerged Fermentation
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ABSTRACT This work analyzes the consequences of combining heat treatment with refrigerated storage in strawberry fruit. Strawberries cv. Selva were heat treated in an oven (45°C, 3h) and stored at 0°C for 0,7 or 14 days. Afterwards,... more
ABSTRACT This work analyzes the consequences of combining heat treatment with refrigerated storage in strawberry fruit. Strawberries cv. Selva were heat treated in an oven (45°C, 3h) and stored at 0°C for 0,7 or 14 days. Afterwards, fruits were maintained at 20°C for 48h. The effect of the treatment on texture, surface color, anthocyanins, acidity, sugars, electrolyte leakage, respiration rate, number of Colony Forming Units for bacterias and molds and visual appearance was analyzed. Heat treatments combined with refrigerated storage diminished fruit damage and losses due to fungal decay. 1. Introduction Heat treatments have been used in many fruits to diminish fungal decay, reduce chilling injury, and delay ripening (Lurie, 1998). It would be interesting to study the effect of the combination of heat treatments due to other physical methods. Strawberry fruit is a very perishable soft fruit and refrigeration is the main physical technology used to prolong its shelf life. Civello et al., 1997 found that heat treatments delayed fruit ripening and reduced fruit decay. Garcia et al., (1995) reported that hot water dips reduced pathogen attacks in strawberries. The aim of this work is to study the effect of heat treatments and refrigerated storage on fruit quality and physiology.