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1.
Proc Natl Acad Sci U S A ; 120(4): e2209480119, 2023 01 24.
Artículo en Inglés | MEDLINE | ID: mdl-36649403

RESUMEN

Around 10,000 y ago in southwest Asia, the cessation of a mobile lifestyle and the emergence of the first village communities during the Neolithic marked a fundamental change in human history. The first communities were small (tens to hundreds of individuals) but remained semisedentary. So-called megasites appeared soon after, occupied by thousands of more sedentary inhabitants. Accompanying this shift, the material culture and ancient ecological data indicate profound changes in economic and social behavior. A shift from residential to logistical mobility and increasing population size are clear and can be explained by either changes in fertility and/or aggregation of local groups. However, as sedentism increased, small early communities likely risked inbreeding without maintaining or establishing exogamous relationships typical of hunter-gatherers. Megasites, where large populations would have made endogamy sustainable, could have avoided this risk. To examine the role of kinship practices in the rise of megasites, we measured strontium and oxygen isotopes in tooth enamel from 99 individuals buried at Pinarbasi, Boncuklu, and Çatalhöyük (Turkey) over 7,000 y. These sites are geographically proximate and, critically, span both early sedentary behaviors (Pinarbasi and Boncuklu) and the rise of a local megasite (Çatalhöyük). Our data are consistent with the presence of only local individuals at Pinarbasi and Boncuklu, whereas at Çatalhöyük, several nonlocals are present. The Çatalhöyük data stand in contrast to other megasites where bioarchaeological evidence has pointed to strict endogamy. These different kinship behaviors suggest that megasites may have arisen by employing unique, community-specific kinship practices.


Asunto(s)
Estilo de Vida , Conducta Social , Humanos , Historia Antigua , Turquía , Estroncio , Conducta Sedentaria
2.
Plant Physiol ; 191(1): 219-232, 2023 01 02.
Artículo en Inglés | MEDLINE | ID: mdl-35972400

RESUMEN

The cuticle is a protective extracellular matrix that covers the above-ground epidermis of land plants. Here, we studied the cuticle of tomato (Solanum lycopersicum L.) fruits in situ using confocal Raman microscopy. Microsections from cuticles isolated at different developmental stages were scanned to visualize cuticle components with a spatial resolution of 342 nm by univariate and multivariate data analysis. Three main components, cutin, polysaccharides, and aromatics, were identified, with the latter exhibiting the strongest Raman scattering intensity. Phenolic acids and flavonoids were differentiated within the cuticle, and three schematic cuticle models were identified during development. Phenolic acids were found across the entire cuticle at the earliest stage of development, i.e. during the formation of the procuticle layer. Based on a mixture analysis with reference component spectra, the phenolic acids were identified as mainly esterified p-coumaric acid together with free p-hydroxybenzoic acid. During the cell expansion period of growth, phenolic acids accumulated in an outermost layer of the cuticle and in the middle region of the pegs. In these stages of development, cellulose and pectin were detected next to the inner cuticle region, close to the epidermal cell where flavonoid impregnation started during ripening. In the first ripening stage, chalconaringenin was observed, while methoxylated chalcones were chosen by the algorithm to fit the mature cuticle spectra. The colocation of carbohydrates, esterified p-coumaric acid, and methoxylated chalconaringenin suggests that the latter two link polysaccharide and cutin domains. Elucidating the different distribution of aromatics within the cuticle, suggests important functions: (1) overall impregnation conferring mechanical and thermal functions (2) the outermost phenolic acid layer displaying UV-B protection of the plant tissue.


Asunto(s)
Solanum lycopersicum , Frutas , Microquímica , Polisacáridos/análisis , Epidermis de la Planta
3.
Phys Chem Chem Phys ; 25(18): 12791-12799, 2023 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-37129056

RESUMEN

Coumaric acids and flavonoids play pivotal roles in protecting plants against ultraviolet radiation (UVR) exposure. In this work, we focus our photoprotection studies on p-coumaric acid and the flavonoid naringenin chalcone. Photoprotection is well-understood in p-coumaric acid; in contrast, information surrounding photoprotection in naringenin chalcone is lacking. Additionally, and vitally, how these two species work in unison to provide photoprotection across the UV-B and UV-A is unknown. Herein, we employ transient absorption spectroscopy together with steady-state irradiation studies to unravel the photoprotection mechanism of a solution of p-coumaric acid and naringenin chalcone. We find that the excited state dynamics of p-coumaric acid are significantly altered in the presence of naringenin chalcone. This finding concurs with quenching of the p-coumaric acid fluorescence with increasing concentration of naringenin chalcone. We propose a Förster energy transfer mechanism is operative via the formation of dipole-dipole interactions between p-coumaric acid and naringenin chalcone. To our knowledge, this is the first demonstration in plants of a synergic effect between two classes of phenolics to bypass the potentially damaging effects of UVR.


Asunto(s)
Frutas , Solanum lycopersicum , Frutas/química , Rayos Ultravioleta , Flavonoides/análisis , Flavonoides/química , Fenoles , Plantas/química , Análisis Espectral
4.
Int J Mol Sci ; 23(9)2022 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-35563041

RESUMEN

Retrieving high-quality endogenous ancient DNA (aDNA) poses several challenges, including low molecular copy number, high rates of fragmentation, damage at read termini, and potential presence of exogenous contaminant DNA. All these factors complicate a reliable reconstruction of consensus aDNA sequences in reads from high-throughput sequencing platforms. Here, we report findings from a thorough evaluation of two alternative tools (ANGSD and schmutzi) aimed at overcoming these issues and constructing high-quality ancient mitogenomes. Raw genomic data (BAM/FASTQ) from a total of 17 previously published whole ancient human genomes ranging from the 14th to the 7th millennium BCE were retrieved and mitochondrial consensus sequences were reconstructed using different quality filters, with their accuracy measured and compared. Moreover, the influence of different sequence parameters (number of reads, sequenced bases, mean coverage, and rate of deamination and contamination) as predictors of derived sequence quality was evaluated. Complete mitogenomes were successfully reconstructed for all ancient samples, and for the majority of them, filtering substantially improved mtDNA consensus calling and haplogroup prediction. Overall, the schmutzi pipeline, which estimates and takes into consideration exogenous contamination, appeared to have the edge over the much faster and user-friendly alternative method (ANGSD) in moderate to high coverage samples (>1,000,000 reads). ANGSD, however, through its read termini trimming filter, showed better capabilities in calling the consensus sequence from low-quality samples. Among all the predictors of overall sample quality examined, the strongest correlation was found for the available number of sequence reads and bases. In the process, we report a previously unassigned haplogroup (U3b) for an Early Chalcolithic individual from Southern Anatolia/Northern Levant.


Asunto(s)
ADN Mitocondrial , Genoma Mitocondrial , ADN Antiguo , ADN Mitocondrial/genética , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Humanos , Análisis de Secuencia de ADN/métodos
5.
Plant Physiol ; 183(4): 1622-1637, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32457092

RESUMEN

The aerial parts of plants, including the leaves, fruits and non-lignified stems, are covered with a protective cuticle, largely composed of the polyester cutin. Two mechanisms of cutin deposition have been identified in tomato (Solanum lycopersicum) fruit. The contribution of each mechanism to cutin synthesis and deposition has shown a temporal and coordinated sequence that correlates with the two periods of organ growth, cell division and cell expansion. Cutinsomes, self-assembled particles composed of esterified cutin monomers, are involved in the synthesis of the procuticle during cell division and provide a template for further cutin deposition. CUTIN SYNTHASE1 (CUS1), an acyl transferase enzyme that links cutin monomers, contributes to massive cuticle deposition during the early stages of the cell expansion period by incorporating additional cutin to the procuticle template. However, cutin deposition and polymerization appear to be part of a more complex biological scenario, which is yet not fully understood. CUS1 is also associated with the coordinated growth of the cutinized and non-cutinized domains of the outer epidermal wall, and affects cell size. A dynamic and complex interplay linking cutin synthesis with cell wall development and epidermal cell size has been identified.


Asunto(s)
Frutas/enzimología , Frutas/metabolismo , Lípidos de la Membrana/metabolismo , Proteínas de Plantas/metabolismo , Solanum lycopersicum/enzimología , Solanum lycopersicum/metabolismo , Regulación de la Expresión Génica de las Plantas
6.
Phys Chem Chem Phys ; 23(33): 18068-18077, 2021 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-34388230

RESUMEN

In this study, the theoretical and experimental results on the molecular structure and reactivity of the plant flavonoids naringenin chalcone and naringenin are reported. UV-vis and Raman spectra were recorded and their main bands have been assigned theoretically. Moreover, the analysis of the naringenin chalcone-naringenin cyclization-isomerization reaction and the formation of homodimers and heterodimers have been performed within a DFT framework. The presence of H-bonded water networks is mandatory to make the cyclization energetically suitable, suggesting that this equilibrium will occur in an aqueous intracellular environment rather than in the extracellular and hydrophobic plant cuticles. Additionally, the preferential formation of homodimers stabilized by π-π stacking that will interact with other dimers by H-bonding over the formation of naringenin chalcone-naringenin heterodimers is also proposed in a hydrophobic environment. These results give a plausible model to explain how flavonoids are located within the cuticle molecular arrangement.


Asunto(s)
Flavanonas/química , Teoría Funcional de la Densidad , Dimerización , Estructura Molecular , Estereoisomerismo
7.
Environ Res ; 197: 111021, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33774014

RESUMEN

Neonicotinoids sonochemical oxidation at high-frequency ultrasound (MHz range) has been carried out in ultrapure and natural surface-water matrices (river, reservoir and wastewater treatment plant effluent). To evaluate the influence of the operating variables, that is initial pollutant concentration, ultrasound frequency, ultrasound power, and pulse-stop time a Box-Behnken experimental design was planned. Optimal results were obtained using a frequency of 578 kHz, a power of 40 W L-1, with a pollutant concentration of 1 µM (for each pesticide), and using a pulse-stop time of 100 ms. The experimental data adjustment using the Langmuir-Hinshelwood heterogeneous kinetic model showed that neonicotinoids oxidation was carried out in the bubble-liquid interface by the attack of hydroxyl radicals. Experiments performed in the presence of radical scavengers, that is, methanol, ethanol and tert-butyl alcohol corroborated this reaction mechanism. The influence of some environmental conditions such as pH, presence of soluble inorganic species (Cl-, SO42-, NO3-, HPO42-, HCO3-) and soluble organic species (humic acids content) were established. Finally, the aqueous matrix's influence was investigated for three natural surface water cases, and the results were rationalized according to the main water physicochemical characteristics.


Asunto(s)
Plaguicidas , Contaminantes Químicos del Agua , Purificación del Agua , Sustancias Húmicas , Radical Hidroxilo , Neonicotinoides , Oxidación-Reducción , Contaminantes Químicos del Agua/análisis
8.
Aten Primaria ; 51(4): 236-244, 2019 04.
Artículo en Español | MEDLINE | ID: mdl-29728286

RESUMEN

AIM: To evaluate the effectiveness of a 9 months of supervised Physical Activity (PA) Program with sociocultural activities, on self-esteem and its association on the control of chronic diseases in adult primary care users. DESIGN: Multicenter, randomized, controlled community intervention. LOCATION: 4 Primary care centers in Reus-Tarragona, Spain. PARTICIPANTS: 364 subjects, randomized to the Control Group (CG=104) and Intervention Group (IG=260). INTERVENTION: Supervised walking program of 120min/week with sociocultural activities once a month. MAIN MEASUREMENTS: At baseline and at post-intervention we assessed: PA (IPAQ-S), self-esteem (Rosenberg scale) and cardiovascular indicators: smoking, systolic (SBP) and diastolic (DBP) blood pressure, serum LDL and HDL cholesterol, and serum glucose. Sociodemographic characteristics and diagnostic of chronic diseases are recorded. RESULTS: The Program increased the PA in the IG (P=.001), while it decreased in the CG (P=.002), and also the self-esteem in the group of participants (1.28 points, P=.006) and in the groups with diagnoses of hypertension (1.60 points, P=.005), dyslipidemia (1.62 points, P=.012), excess weight (1.24 points, P=.011) or anxiety/depression (1.53 points, P=.045), assessed by multivariate statistical models. The increase in self-esteem during the intervention decreased SBP -0.5mmHg (P=.030) in the hypertension group, regardless of baseline SBP and the effect of the intervention. CONCLUSION: The PA program increased the PA and self-esteem in adult primary care users. The increase of self-esteem improved the control of SBP in hypertensive patients.


Asunto(s)
Enfermedad Crónica/psicología , Evaluación de Programas y Proyectos de Salud , Autoimagen , Participación Social/psicología , Caminata/psicología , Anciano , Ansiedad/psicología , Presión Sanguínea , Depresión , Dislipidemias/psicología , Ejercicio Físico/psicología , Femenino , Humanos , Hipertensión/psicología , Masculino , Persona de Mediana Edad , Sobrepeso/psicología , Atención Primaria de Salud , Clase Social , Factores de Tiempo
9.
Glob Chang Biol ; 24(7): 2749-2751, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29668107

RESUMEN

Climatic stressors due to global change induce important modifications to the chemical composition of plant cuticles and their biophysical properties. In particular, plant cuticles can become heavier, stiffer and more inert, improving plant protection.


Asunto(s)
Adaptación Fisiológica , Cambio Climático , Epidermis de la Planta/fisiología , Plantas , Temperatura , Agua , Ceras
10.
Plant Physiol ; 170(2): 935-46, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26668335

RESUMEN

The epidermis plays a pivotal role in plant development and interaction with the environment. However, it is still poorly understood, especially its outer epidermal wall: a singular wall covered by a cuticle. Changes in the cuticle and cell wall structures are important to fully understand their functions. In this work, an ultrastructure and immunocytochemical approach was taken to identify changes in the cuticle and the main components of the epidermal cell wall during tomato fruit development. A thin and uniform procuticle was already present before fruit set. During cell division, the inner side of the procuticle showed a globular structure with vesicle-like particles in the cell wall close to the cuticle. Transition between cell division and elongation was accompanied by a dramatic increase in cuticle thickness, which represented more than half of the outer epidermal wall, and the lamellate arrangement of the non-cutinized cell wall. Changes in this non-cutinized outer wall during development showed specific features not shared with other cell walls. The coordinated nature of the changes observed in the cuticle and the epidermal cell wall indicate a deep interaction between these two supramolecular structures. Hence, the cuticle should be interpreted within the context of the outer epidermal wall.


Asunto(s)
Pared Celular/ultraestructura , Frutas/crecimiento & desarrollo , Frutas/ultraestructura , Epidermis de la Planta/ultraestructura , Solanum lycopersicum/crecimiento & desarrollo , Solanum lycopersicum/ultraestructura , Recuento de Células , División Celular , Proliferación Celular , Celulosa/metabolismo , Frutas/citología , Solanum lycopersicum/citología , Pectinas/metabolismo , Epidermis de la Planta/anatomía & histología , Epidermis de la Planta/citología , Epidermis de la Planta/crecimiento & desarrollo
11.
J Exp Bot ; 68(19): 5389-5400, 2017 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-29040673

RESUMEN

The assembly of the lipophilic cuticle layer and suberin lamellae, approximately 450 million years ago, was a major evolutionary development that enabled plants to colonize terrestrial habitats. The cuticle layer is composed of cutin polyester and embedded cuticular waxes, whereas the suberin lamellae consist of very long chain fatty acid derivatives, glycerol, and phenolics cross-linked with alkyl ferulate-embedded waxes. Due to their substantial biological roles in plant life, the mechanisms underlying the assembly of these structures have been extensively investigated. In the last decade, the introduction of 'omics' approaches, including genomics, transcriptomics, proteomics, and metabolomics, have been key in the identification of novel genetic and chemical elements involved in the formation and function of the cuticle layer and suberin lamellae. This review summarizes contemporary studies that utilized various large-scale, 'omics' strategies in combination with novel technologies to unravel how building blocks and polymers of these lipophilic barriers are made, and moreover linking structure to function along developmental programs and stress responses. We anticipate that the studies discussed here will inspire scientists studying lipophilic barriers to integrate complementary 'omics' approaches in their efforts to tackle as yet unresolved questions and engage the main challenges of the field to date.


Asunto(s)
Perfilación de la Expresión Génica/métodos , Genómica/métodos , Metabolómica/métodos , Epidermis de la Planta/fisiología , Fenómenos Fisiológicos de las Plantas/genética , Proteómica/métodos , Perfilación de la Expresión Génica/instrumentación , Genómica/instrumentación , Metabolómica/instrumentación , Epidermis de la Planta/genética , Proteómica/instrumentación , Ceras/metabolismo
12.
J Exp Bot ; 68(19): 5401-5410, 2017 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-28992177

RESUMEN

Cutin is the main component of plant cuticles constituting the framework that supports the rest of the cuticle components. This biopolymer is composed of esterified bi- and trifunctional fatty acids. Despite its ubiquity in terrestrial plants, it has been underutilized as raw material due to its insolubility and lack of melting point. However, in recent years, a few technologies have been developed to obtain cutin monomers from several agro-wastes at an industrial scale. This review is focused on the description of cutin properties, biodegradability, chemical composition, processability, abundance, and the state of art of the fabrication of cutin-based materials in order to evaluate whether this biopolymer can be considered a source for the production of renewable materials.


Asunto(s)
Agricultura , Conservación de los Recursos Naturales/métodos , Lípidos de la Membrana/análisis , Plásticos/análisis , Residuos Sólidos/análisis , Industria de Procesamiento de Alimentos , Eliminación de Residuos/métodos
13.
Physiol Plant ; 161(4): 560-567, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28767133

RESUMEN

Cutinsomes, spherical nanoparticles containing cutin mono- and oligomers, are engaged in cuticle formation. Earlier they were revealed to participate in cuticle biosynthesis in Solanum lycopersicum fruit and Ornithogalum umbellatum ovary epidermis. Here, transmission electron microscopy (TEM) and immunogold labeling with antibody against the cutinsomes were applied to aerial cotyledon epidermal cells of Arabidopsis thaliana mature embryos. TEM as well as gold particles conjugated with the cutinsome antibody revealed these structures in the cytoplasm, near the plasmalemma, in the cell wall and incorporated into the cuticle. Thus, the cutinsomes most probably are involved in the formation of A. thaliana embryo cuticle and this model plant is another species in which these specific structures participate in the building of cuticle in spite of the lack of the lipotubuloid metabolon. In addition, a mechanism of plant cuticle lipid biosynthesis based on current knowledge is proposed.


Asunto(s)
Arabidopsis/metabolismo , Arabidopsis/genética , Cotiledón/genética , Cotiledón/metabolismo , Regulación de la Expresión Génica de las Plantas/genética , Regulación de la Expresión Génica de las Plantas/fisiología , Microscopía Electrónica de Transmisión , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Semillas/genética , Semillas/metabolismo
14.
Plant Physiol ; 168(3): 1036-48, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26019301

RESUMEN

Fruit development and ripening entail key biological and agronomic events, which ensure the appropriate formation and dispersal of seeds and determine productivity and yield quality traits. The MADS box gene Arlequin/tomato Agamous-like1 (hereafter referred to as TAGL1) was reported as a key regulator of tomato (Solanum lycopersicum) reproductive development, mainly involved in flower development, early fruit development, and ripening. It is shown here that silencing of the TAGL1 gene (RNA interference lines) promotes significant changes affecting cuticle development, mainly a reduction of thickness and stiffness, as well as a significant decrease in the content of cuticle components (cutin, waxes, polysaccharides, and phenolic compounds). Accordingly, overexpression of TAGL1 significantly increased the amount of cuticle and most of its components while rendering a mechanically weak cuticle. Expression of the genes involved in cuticle biosynthesis agreed with the biochemical and biomechanical features of cuticles isolated from transgenic fruits; it also indicated that TAGL1 participates in the transcriptional control of cuticle development mediating the biosynthesis of cuticle components. Furthermore, cell morphology and the arrangement of epidermal cell layers, on whose activity cuticle formation depends, were altered when TAGL1 was either silenced or constitutively expressed, indicating that this transcription factor regulates cuticle development, probably through the biosynthetic activity of epidermal cells. Our results also support cuticle development as an integrated event in the fruit expansion and ripening processes that characterize fleshy-fruited species such as tomato.


Asunto(s)
Frutas/genética , Genes de Plantas , Proteínas de Dominio MADS/genética , Epidermis de la Planta/crecimiento & desarrollo , Solanum lycopersicum/crecimiento & desarrollo , Solanum lycopersicum/genética , Transcripción Genética , Fenómenos Biomecánicos , Vías Biosintéticas/genética , Flores/anatomía & histología , Flores/fisiología , Frutas/citología , Frutas/crecimiento & desarrollo , Regulación del Desarrollo de la Expresión Génica , Regulación de la Expresión Génica de las Plantas , Proteínas de Dominio MADS/metabolismo , Fenotipo , Epidermis de la Planta/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Interferencia de ARN , ARN Mensajero/genética , ARN Mensajero/metabolismo
15.
Plant Physiol ; 166(3): 1371-86, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25277718

RESUMEN

Tomato (Solanum lycopersicum) fruit ripening is accompanied by an increase in CHALCONE SYNTHASE (CHS) activity and flavonoid biosynthesis. Flavonoids accumulate in the cuticle, giving its characteristic orange color that contributes to the eventual red color of the ripe fruit. Using virus-induced gene silencing in fruits, we have down-regulated the expression of SlCHS during ripening and compared the cuticles derived from silenced and nonsilenced regions. Silenced regions showed a pink color due to the lack of flavonoids incorporated to the cuticle. This change in color was accompanied by several other changes in the cuticle and epidermis. The epidermal cells displayed a decreased tangential cell width; a decrease in the amount of cuticle and its main components, cutin and polysaccharides, was also observed. Flavonoids dramatically altered the cuticle biomechanical properties by stiffening the elastic and viscoelastic phase and by reducing the ability of the cuticle to deform. There seemed to be a negative relation between SlCHS expression and wax accumulation during ripening that could be related to the decreased cuticle permeability to water observed in the regions silencing SlCHS. A reduction in the overall number of ester linkages present in the cutin matrix was also dependent on the presence of flavonoids.


Asunto(s)
Aciltransferasas/genética , Epidermis de la Planta/citología , Solanum lycopersicum/fisiología , Aciltransferasas/metabolismo , Flavonoides/metabolismo , Frutas/citología , Frutas/fisiología , Regulación de la Expresión Génica de las Plantas , Silenciador del Gen , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Espectroscopía Infrarroja por Transformada de Fourier , Ceras/química
16.
New Phytol ; 202(3): 790-802, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24571168

RESUMEN

In this study, growth-dependent changes in the mechanical properties of the tomato (Solanum lycopersicum) cuticle during fruit development were investigated in two cultivars with different patterns of cuticle growth and accumulation. The mechanical properties were determined in uniaxial tensile tests using strips of isolated cuticles. Changes in the functional groups of the cuticle chemical components were analysed by attenuated total reflectance-Fourier transform infrared (ATR-FTIR). The early stages of fruit growth are characterized by an elastic cuticle, and viscoelastic behaviour only appeared at the beginning of cell enlargement. Changes in the cutin:polysaccharide ratio during development affected the strength required to achieve viscoelastic deformation. The increase in stiffness and decrease in extensibility during ripening, related to flavonoid accumulation, were accompanied by an increase in cutin depolymerization as a result of a reduction in the overall number of ester bonds. Quantitative changes in cuticle components influence the elastic/viscoelastic behaviour of the cuticle. The cutin:polysaccharide ratio modulates the stress required to permanently deform the cuticle and allow cell enlargement. Flavonoids stiffen the elastic phase and reduce permanent viscoelastic deformation. Ripening is accompanied by a chemical cleavage of cutin ester bonds. An infrared (IR) band related to phenolic accumulation can be used to monitor changes in the cutin esterification index.


Asunto(s)
Frutas/crecimiento & desarrollo , Frutas/fisiología , Epidermis de la Planta/crecimiento & desarrollo , Epidermis de la Planta/fisiología , Solanum lycopersicum/fisiología , Fenómenos Biomecánicos , Elasticidad , Esterificación , Genotipo , Solanum lycopersicum/genética , Lípidos de la Membrana/metabolismo , Fenoles/metabolismo , Espectroscopía Infrarroja por Transformada de Fourier , Viscosidad
17.
Front Plant Sci ; 15: 1343452, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38434425

RESUMEN

Fruit cracking, a widespread physiological disorder affecting various fruit crops and vegetables, has profound implications for fruit quality and marketability. This mini review delves into the multifaceted factors contributing to fruit cracking and emphasizes the pivotal roles of environmental and agronomic factors in its occurrence. Environmental variables such as temperature, relative humidity, and light exposure are explored as determinants factors influencing fruit cracking susceptibility. Furthermore, the significance of mineral nutrition and plant growth regulators in mitigating fruit cracking risk is elucidated, being calcium deficiency identified as a prominent variable in various fruit species. In recent years, precision farming and monitoring systems have emerged as valuable tools for managing environmental factors and optimizing fruit production. By meticulously tracking parameters such as temperature, humidity, soil moisture, and fruit skin temperature, growers can make informed decisions to prevent or alleviate fruit cracking. In conclusion, effective prevention of fruit cracking necessitates a comprehensive approach that encompasses both environmental and agronomic factors.

18.
Polymers (Basel) ; 16(6)2024 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-38543419

RESUMEN

Biodegradable mulching films are a very attractive solution to agronomical practices intended to achieve more successful crop results. And, in this context, the employment of agricultural and industrial food residues as starting material for their production is an alternative with economic and environmental advantages. This work reports the preparation of bilayer films having two different wettability characteristics from three bio-derived biopolymers: TEMPO-oxidized cellulose nanofibers isolated from infused Yerba Mate residues, Chitosan and Polylactic acid. The infused Yerba Mate residues, the isolated and oxidized cellulose nanofibers, and the films were characterized. Nanofibrillation yield, optical transmittance, cationic demand, carboxyl content, intrinsic viscosity, degree of polymerization, specific surface area and length were studied for the (ligno)cellulose nanofibers. Textural and chemical analysis, thermal and mechanical properties studies, as well as water and light interactions were included in the characterization of the films. The bilayer films are promising materials to be used as mulching films.

19.
Sci Adv ; 9(39): eadi3055, 2023 Sep 29.
Artículo en Inglés | MEDLINE | ID: mdl-37756397

RESUMEN

Plant material culture can offer unique insights into the ways of life of prehistoric societies; however, its perishable nature has prevented a thorough understanding of its diverse and complex uses. Sites with exceptional preservation of organic materials provide a unique opportunity for further research. The burial site of Cueva de los Murciélagos in southern Iberia, uncovered during 19th-century mining activities, contained the best-preserved hunter-gatherer basketry in southern Europe, together with other unique organic artifacts associated with the first farming communities, such as sandals and a wooden hammer. We present 14 14C dates for the perishable artifacts (N = 76), situating the assemblage between the Early and Middle Holocene (c. 7500 to 4200 cal BCE). Our integrated analysis includes raw material determination and technological and chrono-cultural contextualization of this unique and important set of materials.

20.
Plant Physiol ; 156(4): 2098-108, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21685175

RESUMEN

The surface of peach (Prunus persica 'Calrico') is covered by a dense indumentum, which may serve various protective purposes. With the aim of relating structure to function, the chemical composition, morphology, and hydrophobicity of the peach skin was assessed as a model for a pubescent plant surface. Distinct physicochemical features were observed for trichomes versus isolated cuticles. Peach cuticles were composed of 53% cutan, 27% waxes, 23% cutin, and 1% hydroxycinnamic acid derivatives (mainly ferulic and p-coumaric acids). Trichomes were covered by a thin cuticular layer containing 15% waxes and 19% cutin and were filled by polysaccharide material (63%) containing hydroxycinnamic acid derivatives and flavonoids. The surface free energy, polarity, and work of adhesion of intact and shaved peach surfaces were calculated from contact angle measurements of water, glycerol, and diiodomethane. The removal of the trichomes from the surface increased polarity from 3.8% (intact surface) to 23.6% and decreased the total surface free energy chiefly due to a decrease on its nonpolar component. The extraction of waxes and the removal of trichomes led to higher fruit dehydration rates. However, trichomes were found to have a higher water sorption capacity as compared with isolated cuticles. The results show that the peach surface is composed of two different materials that establish a polarity gradient: the trichome network, which has a higher surface free energy and a higher dispersive component, and the cuticle underneath, which has a lower surface free energy and higher surface polarity. The significance of the data concerning water-plant surface interactions is discussed within a physiological context.


Asunto(s)
Frutas/anatomía & histología , Modelos Biológicos , Prunus/anatomía & histología , Adhesividad , Cromatografía Líquida de Alta Presión , Deshidratación , Frutas/citología , Frutas/ultraestructura , Fenoles/metabolismo , Epidermis de la Planta/citología , Epidermis de la Planta/ultraestructura , Prunus/citología , Prunus/ultraestructura , Espectroscopía Infrarroja por Transformada de Fourier , Propiedades de Superficie , Termodinámica , Agua/química
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