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1.
Materials (Basel) ; 17(8)2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38673258

RESUMO

Cellulosic fibers obtained from Barley straw were utilized to reinforce PHB. Four different processed fibers were employed as reinforcing material: sawdust (SW), defibered (DFBF), delignified (DBF), and bleached (BBF) fibers. The composite was processed from two different perspectives: a discontinuous (bach) and an intensification process (extrusion). Once processed and transformed into final shape specimens, the materials were characterized by mechanical testing (tensile mode), scanning electron microscopy, and theoretical simulations by finite elements analysis (FEA). In terms of mechanical properties, only the elastic moduli (Et) exhibited results ranging from 37% to 170%, depending on the reinforcement composition. Conversely, strengths at break, under both tensile and bending tests, tended to decrease, indicating poor affinity between the components. Due to the mechanical treatment applied on the fiber, DFBF emerged as the most promising filler, with mechanical properties closest to those of neat PHB. DFBF-based composites were subsequently produced through process intensification using a twin-screw extruder, and molded into flowerpots. Mechanical results showed almost identical properties between the discontinuous and intensification processes. The suitability of the material for agriculture flowerpots was demonstrated through finite analysis simulation (FEA), which revealed that the maximum von Mises stresses (5.38 × 105 N/m2) and deformations (0.048 mm) were well below the limits of the composite materials.

2.
Plants (Basel) ; 13(4)2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38498479

RESUMO

The productivity of durum wheat in Mediterranean regions is greatly reduced by water deficits that vary in intensity and time of occurrence. The development of more tolerant cultivars is the main solution for fighting these stresses, but this requires prior study of their mechanisms. The involvement of the root system in drought avoidance is of major importance. It is in this context that the present work attempts to establish the impact of morpho-anatomical remodeling of seminal roots on dehydration avoidance at the javelina stage in five durum wheat genotypes grown under three water regimes, 100%, 60% and 30% of field capacity (FC). In the last two treatments, which were applied by stopping irrigation, moisture was concentrated mainly in the depths of the substrate cylinders and was accompanied by greater root elongation compared with the control. The elongation reached rates of 20 and 22% in the ACSAD 1231 genotype and 12 and 13% in the Waha genotype, in the 60% FC and 30% FC treatments respectively. The seminal roots anatomy was also modified by water deficit in all genotypes but to different degrees. The diameter of vessels in the late metaxylem vessels was reduced, reaching 17.3 and 48.2% in the Waha genotype in the 60% FC and 30% FC treatments, respectively. The water deficit also increased the number of vessels in the early metaxylem, while reducing the diameter of its conducting vessels. ACSAD 1361 and Langlois genotypes stood out with the highest rates of diameter reduction. The morpho-anatomical transformations of the roots contributed effectively to the plants' absorption of water and, consequently, to the maintenance of a fairly high relative water content, approaching 80%.

3.
Polymers (Basel) ; 14(21)2022 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-36365571

RESUMO

In recent years, the demand for environmental sustainability has caused a great interest in finding novel polymer materials from natural resources that are both biodegradable and eco-friendly. Natural biodegradable polymers can displace the usage of petroleum-based synthetic polymers due to their renewability, low toxicity, low costs, biocompatibility, and biodegradability. The development of novel starch-based bionanocomposites with improved properties has drawn specific attention recently in many applications, including food, agriculture, packaging, environmental remediation, textile, cosmetic, pharmaceutical, and biomedical fields. This paper discusses starch-based nanocomposites, mainly with nanocellulose, chitin nanoparticles, nanoclay, and carbon-based materials, and their applications in the agriculture, packaging, biomedical, and environment fields. This paper also focused on the lifecycle analysis and degradation of various starch-based nanocomposites.

4.
Front Biosci (Landmark Ed) ; 27(9): 259, 2022 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-36224017

RESUMO

BACKGROUND: Tomato pomace (TP) is a coproduct generated by the extraction of tomato pulp, and is a potential source of bioactive molecules. In this study, we isolated several fractions from TP and evaluated their biological properties. MATERIALS AND METHODS: TP was treated by maceration at room temperature with green solvents (ethanol, ethyl acetate, ethanol:water and ethanol:ethyl acetate) or supercritical CO2 (SC-CO2). The extracts were analyzed by HPLC-DAD to determine their composition, and their antioxidant activity was assessed. The potential therapeutic effects of the isolated fractions were assessed in vitro. RESULTS: We identified 30 molecules on chromatography profiles, which revealed an abundance in phenolic acids, carotenoids, flavonoids and tannins, with differences in selectivity according to the solvent and pretreatment used. The highest radical scavenging activities were measured at 64-72% inhibition, corresponding to the ethanol or ethanol:water extracts with the highest polyphenol or flavonoid contents. Carotenoid content was increased by chemical pretreatment, to attain levels of 161 mg ß-carotene/g ethyl acetate extract. This level of carotenoids seemed to have anti-inflammatory effects, with an IC50 of 9.3 µg/mL. In terms of anti-diabetic effects, the activities of α-glucosidase and α-amylase were best inhibited by extraction in an ethanol-to-water mixture (50:50). Cytotoxicity in a tumor cell line were highest for SC-CO2 extracts (64.5% inhibition) and for ethanol extracts obtained after the enzymatic pretreatment of TP (37% inhibition). Some extracts also had dose-dependent activity against Zika virus. CONCLUSIONS: New fractions obtained from TP with ecocompatible solvents in mild conditions are rich in bioactive molecules. A comparison of the chromatographic profiles of the extracts led to the identification of several key molecules with therapeutic properties. The chemical pretreatment of TP is justified as a mean of increasing the carotenoid content of ethyl acetate fractions, whereas enzymatic pretreatment can increase the antioxidant activity of ethyl acetate fractions and increase the cytotoxicity of ethanol fractions. The SC-CO2 fraction contained a smaller number of metabolites detectable on HPLC, but it had high levels of cytotoxicity and antioxidant activity. Finally, the fractions obtained appeared to be suitable for use to target one or several of the biological activities studied.


Assuntos
Antioxidantes , Solanum lycopersicum , Acetatos , Anti-Inflamatórios/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Dióxido de Carbono , Etanol , Flavonoides/farmacologia , Humanos , Fenóis/farmacologia , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Polifenóis , Solventes/análise , Solventes/química , Taninos/análise , Água , alfa-Amilases , alfa-Glucosidases , beta Caroteno
5.
Front Plant Sci ; 13: 837441, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35845677

RESUMO

A survey of plant-based wastes identified sunflower (Helianthus annuus) bark extract (SBE), produced via twin-screw extrusion, as a potential biostimulant. The addition of SBE to Arabidopsis (Arabidopsis thaliana) seedlings cultured in vitro showed a dose-dependent response, with high concentrations causing severe growth inhibition. However, when priming seeds with SBE, a small but significant increase in leaf area was observed at a dose of 0.5 g of lyophilized powder per liter. This optimal concentration of SBE in the culturing medium alleviated the growth inhibition caused by 100 mM NaCl. The recovery in shoot growth was accompanied by a pronounced increase in photosynthetic pigment levels and a stabilization of osmotic homeostasis. SBE-primed leaf discs also showed a similar protective effect. SBE mitigated salt stress by reducing the production of reactive oxygen species (ROS) (e.g., hydrogen peroxide) by about 30% and developing more expanded true leaves. This reduction in ROS levels was due to the presence of antioxidative agents in SBE and by activating ROS-eliminating enzymes. Polyphenols, carbohydrates, proteins, and other bioactive compounds detected in SBE may have contributed to the cellular redox homeostasis in salt-stressed plants, thus promoting early leaf development by relieving shoot apical meristem arrest. Sunflower stalks from which SBE is prepared can therefore potentially be valorized as a source to produce biostimulants for improving salt stress tolerance in crops.

6.
RMD Open ; 8(1)2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35537796

RESUMO

OBJECTIVE: There is little known about SARS-CoV-2 infection in patients with systemic autoinflammatory disease (SAID). This study aimed to describe epidemiological features associated with severe disease form and death. Mortality between patients with and without SAID hospitalised for SARS-CoV-2 infection was compared. METHODS: A national multicentric prospective cohort study was conducted from the French Rheumatic and Musculoskeletal Diseases (RMD) COVID-19 cohort. Patients with SAID were matched with patients with non-SAID on age±7 years, gender and number of comorbidities to consider important confounding factors. Impact of SAID on severity of SARS-CoV-2 infection was analysed using multinomial logistic regression for severity in three classes (mild, moderate and severe with mild status as reference). Fine-Gray regression model for length of hospital stay and binomial logistic regression model for risk of death at 30 days. RESULTS: We identified 117 patients with SAID (sex ratio 0.84, 17 children) and compared them with 1545 patients with non-autoinflammatory immune-mediated inflammatory disorders (non-SAID). 67 patients had a monogenic SAID (64 with familial Mediterranean fever). Other SAIDs were Behçet' disease (n=21), undifferentiated SAID (n=16), adult-onset Still disease (n=9) and systemic-onset juvenile idiopathic arthritis (n=5). Ten adults developed severe form (8.6%). Six patients died. All children had a benign disease. After matching on age±7 years, sex and number of comorbidities, no significant difference between the two groups in length of stay and the severity of infection was noted. CONCLUSION: As identified in the whole French RMD COVID-19 cohort, patients with SAID on corticosteroids and with multiple comorbidities are prone to develop more severe COVID-19 forms.


Assuntos
COVID-19 , Doenças Hereditárias Autoinflamatórias , Doenças Musculoesqueléticas , Adulto , COVID-19/epidemiologia , Criança , Estudos de Coortes , Humanos , Estudos Prospectivos , SARS-CoV-2
7.
J Vis Exp ; (167)2021 01 27.
Artigo em Inglês | MEDLINE | ID: mdl-33586706

RESUMO

A versatile twin-screw extrusion process to provide an efficient thermo-mechano-chemical pre-treatment on lignocellulosic biomass before using it as source of mechanical reinforcement in fully bio-based fiberboards was developed. Various lignocellulosic crop by-products have already been successfully pre-treated through this process, e.g., cereal straws (especially rice), coriander straw, shives from oleaginous flax straw, and bark of both amaranth and sunflower stems. The extrusion process results in a marked increase in the average fiber aspect ratio, leading to improved mechanical properties of fiberboards. The twin-screw extruder can also be fitted with a filtration module at the end of the barrel. The continuous extraction of various chemicals (e.g., free sugars, hemicelluloses, volatiles from essential oil fractions, etc.) from the lignocellulosic substrate, and the fiber refining can, therefore, be performed simultaneously. The extruder can also be used for its mixing ability: a natural binder (e.g., Organosolv lignins, protein-based oilcakes, starch, etc.) can be added to the refined fibers at the end of the screw profile. The obtained premix is ready to be molded through hot pressing, with the natural binder contributing to fiberboard cohesion. Such a combined process in a single extruder pass improves the production time, production cost, and may lead to reduction in plant production size. Because all the operations are performed in a single step, fiber morphology is better preserved, thanks to a reduced residence time of the material inside the extruder, resulting in enhanced material performances. Such one-step extrusion operation may be at the origin of a valuable industrial process intensification. Compared to commercial wood-based materials, these fully bio-based fiberboards do not emit any formaldehyde, and they could find various applications, e.g., intermediate containers, furniture, domestic flooring, shelving, general construction, etc.


Assuntos
Biotecnologia/instrumentação , Biotecnologia/métodos , Lignina/química , Absorção Fisico-Química , Biomassa , Dessecação , Temperatura Alta , Água/química , Madeira/química
8.
Biomolecules ; 10(7)2020 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-32679821

RESUMO

A new biorefinery approach has been developed in the present study, and applied on cumin (Cuminum cyminum) seeds as a potential source of phytochemicals of interest. Cumin is a popular spice used widely for its distinctive aroma. It is a rich reserve of both vegetable and essential oils. The biorefinery approach here focused on the evaluation of the influence of four different geographical origins (i.e., Lebanon, France, Algeria and Syria) on oil yield and quality in cumin seed, and on the valorization of remaining by-products by investigating their nutritional content and biological activity for the first time. Vegetable and essential oils were extracted, and their compositions were determined. Nutritional traits were also assessed. The delipidated and hydrodistillated cakes just as aromatic water were characterized for their fiber, sugar, protein, phenol and flavonoid contents. Antibacterial and antioxidant activities were also determined. Cumin seeds showed high contents in both vegetable and essential oils, proteins and sugars regardless their origin. Moreover, this Apiaceae species exhibited high levels of petroselinic fatty acid (an isomer of oleic acid) and sterols. Cakes and aromatic water also presented high levels of proteins, fibers, sugars and phenols. These residues revealed interesting antioxidant and antibacterial activities. These results emphasized the potential use of cumin in a biorefinery concept, with a multi-purpose industrial process. In addition, large differences were observed between the four geographical origins for phytochemical contents and compositions. These findings highlight the perspectives for developing selection programs for nutritional traits and industrial interests. All obtained results validate the health promoting effect of cumin composition as well as its industrial importance along with the residues.


Assuntos
Cuminum/química , Óleos Voláteis/análise , Compostos Fitoquímicos/análise , Argélia , Cuminum/classificação , França , Líbano , Valor Nutritivo , Filogeografia , Extratos Vegetais/química , Óleos de Plantas/análise , Sementes/química , Síria
9.
Food Chem ; 326: 127034, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32438233

RESUMO

Coriander contains petroselinic acid, an isomer fatty acid of oleic acid. Coriander seed oil has been proposed as novel food ingredient in the European Union. Field experiments were performed at Auch (France) during two seasons (2010 and 2011). From flowering to maturity, fruits were harvested weekly and oil content and fatty acid (FA) compositions were determined. Fruits presented 2% more oil in 2010 than in 2011. Petroselinic acid (PA) contents was higher in 2011 than in 2010. Oil accumulation began earlier after flowering (2 DAF) in 2011. A first step in accumulation was identified between two and 21 DAF characterized by high SFA and PUFA, which decreased 21 DAF. Subsequently, PA increased to its highest concentration (30-55 DAF) and SFA and PUFA reached their lowest. These results suggest that higher concentrations of PA can be achieved by collecting fruits before full maturity.


Assuntos
Coriandrum/química , Ácidos Graxos/química , Óleos de Plantas/química , Coriandrum/crescimento & desenvolvimento , Frutas/química , Frutas/crescimento & desenvolvimento , Isomerismo , Ácido Oleico/química , Sementes/química
10.
Environ Sci Pollut Res Int ; 27(14): 16121-16133, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32100217

RESUMO

Indoor air quality is a major public health issue. It is related to the choice of construction materials and associated with VOC emissions. Two wood-based commercial panels were tested: a medium-density fiberboard (MDF) and a chipboard (CH), and they were compared to a material produced from a coriander biorefinery (COR). Indicators chosen to compare the materials were physical properties (density, bending properties, surface hardness, thickness swelling, and water absorption) and VOC emissions. Emissions were evaluated in an environmental chamber at 23 °C, 31 °C, and 36 °C, and during 28 days. Carbonyl emissions on day 1 at 23 °C were 74, 146, and 35 µg m-2 h-1, respectively, for MDF, CH, and COR. Terpenic emissions were 12, 185, and 37 µg m-2 h-1, respectively. Higher temperature resulted in higher emissions which decreased over time, except for formaldehyde. VOC emissions depended largely on material and temperature. Formaldehyde emission was 300 to 600 times lower for coriander boards (< 0.2 µg m-2 h-1), making them significantly more environmentally friendly materials in comparison with MDF and chipboard. These results highlight the interest of coriander by-products as raw materials for producing fiberboards with low impact on indoor air quality.


Assuntos
Poluição do Ar em Ambientes Fechados/análise , Coriandrum , Compostos Orgânicos Voláteis/análise , Materiais de Construção , Formaldeído/análise , Madeira/química
11.
Int J Mol Sci ; 18(7)2017 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-28714928

RESUMO

The aim of this study consisted of manufacturing renewable binderless fiberboards from coriander straw and a deoiled coriander press cake, thus at the same time ensuring the valorization of crop residues and process by-products. The press cake acted as a natural binder inside the boards owing to the thermoplastic behavior of its protein fraction during thermopressing. The influence of different fiber-refining methods was evaluated and it was shown that a twin-screw extrusion treatment effectively improved fiber morphology and resulted in fiberboards with enhanced performance as compared to a conventional grinding process. The best fiberboard was produced with extrusion-refined straw using a 0.4 liquid/solid (L/S) ratio and with 40% press cake addition. The water sensitivity of the boards was effectively reduced by 63% through the addition of an extrusion raw material premixing operation and thermal treatment of the panels at 200 °C, resulting in materials with good performance showing a flexural strength of 29 MPa and a thickness swelling of 24%. Produced without the use of any chemical adhesives, these fiberboards could thus present viable, sustainable alternatives for current commercial wood-based materials such as oriented strand board, particleboard and medium-density fiberboard, with high cost-effectiveness.


Assuntos
Materiais de Construção/análise , Teste de Materiais/métodos , Força Compressiva , Conservação dos Recursos Naturais/métodos , Coriandrum , Resistência à Tração , Madeira
12.
Int J Mol Sci ; 19(1)2017 Dec 25.
Artigo em Inglês | MEDLINE | ID: mdl-29295600

RESUMO

In wheat, flag leaf, stem, chaff and awns contribute to grain filling through photosynthesis and/or re-mobilization. Environmental and genetic effects on the relative contribution of each organ were examined by analyzing the consequences of sink-source manipulations (shading and excision) and by comparing carbon isotope discrimination (Δ) values in dry matter (at maturity) and sap (two weeks after anthesis) in six durum wheat genotypes grown in two contrasting seasons. The contribution of flag leaf, stem, chaff and awns to grain filling, estimated by sink-source manipulations, highly varied with the season. The contribution of ear photosynthesis and re-mobilization from the stem increased with post-anthesis water stress. They showed a large genetic variation that was, however, not clearly associated to morphological characteristics of ear and stem. Isotopic imprints of chaff on grain Δ were identified as a possible surrogate of the destructive and cumbersome sink-source manipulations to evaluate the contribution of carbon assimilated in ears or re-mobilized from stem. This might facilitate screening of genetic resources and allow the combining of favourable drought tolerance mechanisms in wheat.


Assuntos
Especificidade de Órgãos , Sementes/crescimento & desenvolvimento , Triticum/crescimento & desenvolvimento , Agricultura , Isótopos de Carbono/metabolismo , Genótipo , Região do Mediterrâneo , Fotossíntese , Característica Quantitativa Herdável , Chuva , Sementes/genética , Temperatura , Triticum/genética
13.
Molecules ; 21(9)2016 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-27617992

RESUMO

Coriander vegetable oil was extracted from fruits of French origin in a 23% yield. The oil was of good quality, with a low amount of free fatty acids (1.8%) and a concurrently high amount of triacylglycerols (98%). It is a rich source of petroselinic acid (C18:1n-12), an important renewable building block, making up 73% of all fatty acids, with also significant amounts of linoleic acid (14%), oleic acid (6%), and palmitic acid (3%). The oil was characterized by a high unsaponifiable fraction, comprising a substantial amount of phytosterols (6.70 g/kg). The main sterol markers were ß-sitosterol (35% of total sterols), stigmasterol (24%), and Δ7-stigmastenol (18%). Squalene was detected at an amount of 0.2 g/kg. A considerable amount of tocols were identified (500 mg/kg) and consisted mainly of tocotrienols, with γ-tocotrienol as the major compound. The phospholipid content was low at 0.3%, of which the main phospholipid classes were phosphatidic acid (33%), phosphatidylcholine (25%), phosphatidylinositol (17%), and phosphatidylethanolamine (17%). About 50% of all phospholipids were non-hydratable. The ß-carotene content was low at 10 mg/kg, while a significant amount of chlorophyll was detected at about 11 mg/kg. An iron content of 1.4 mg/kg was determined through element analysis of the vegetable oil. The influence of fruit origin on the vegetable oil composition was shown to be very important, particularly in terms of the phospholipids, sterols, and tocols composition.


Assuntos
Coriandrum/química , Óleos Voláteis/química , Ácidos Oleicos/química , Óleos de Plantas/química , Ácidos Oleicos/análise , Fosfolipídeos/análise , Fosfolipídeos/química , Fitosteróis/análise , Fitosteróis/química , beta Caroteno/análise , beta Caroteno/química
14.
Bioresour Technol ; 211: 146-53, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27015021

RESUMO

A process has been validated for the deconstruction of lignocellulose on a pilot scale installation using six types of biomass selected for their sustainability, accessibility, worldwide availability, and differences of chemical composition and physical structure. The process combines thermo-mechano-chemical and bio-catalytic action in a single twin-screw extruder. Three treatment phases were sequentially performed: an alkaline pretreatment, a neutralization step coupled with an extraction-separation phase and a bioextrusion treatment. Alkaline pretreatment destructured the wall polymers after just a few minutes and allowed the initial extraction of 18-54% of the hemicelluloses and 9-41% of the lignin. The bioextrusion step induced the start of enzymatic hydrolysis and increased the proportion of soluble organic matter. Extension of saccharification for 24h at high consistency (20%) and without the addition of new enzyme resulted in the production of 39-84% of the potential glucose.


Assuntos
Biocatálise , Lignina/química , Antiácidos/química , Antiácidos/farmacologia , Fracionamento Químico/métodos , Força Compressiva , Glucose/biossíntese , Hidrólise , Lignina/metabolismo , Fenômenos Mecânicos , Projetos Piloto , Polissacarídeos/química , Polissacarídeos/metabolismo , Temperatura
15.
Cardiovasc Pathol ; 24(2): 121-3, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25283127

RESUMO

BACKGROUND: Atrial myxoma (AM) is responsible for multiple serious complications, such as ischemic stroke, and requires cardiac surgery. However, diagnosis and, thus, treatment may be delayed by an initial misleading clinical presentation including nonspecific extracardiac symptoms. Involvement of the peripheral nervous system as a first symptom of AM has been reported only once before and never in the form of multiple mononeuropathy. CASE: We report the case of a 51-year-old woman who had suffered from pharmacoresistant neurological pain sequentially in several peripheral nerve territories for more than a year before the appearance of purpuric macules on the palms and soles and emergence of a biological inflammatory syndrome. Cardioembolic disease was suspected after radiological examination detected multiple asymptomatic renal and splenic infarctions and a small right frontal cortical ischemic stroke. Transoesophageal echocardiography revealed an atrial mass which was removed by surgery. AM was confirmed after histopathological analysis. The neurological pain resolved along with embolic and systemic signs of AM, and the patient has since been free of pain. CONCLUSION: Multiple mononeuropathy is a possible symptom of AM and may precede onset of other embolic or systemic signs by several months.


Assuntos
Neoplasias Cardíacas/complicações , Mononeuropatias/etiologia , Mixoma/complicações , Neuralgia/etiologia , Ecocardiografia Transesofagiana , Feminino , Humanos , Pessoa de Meia-Idade , Púrpura/etiologia
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