This study describes a promising method for understanding how halophytes adapt to extreme saline conditions and to identify populations with greater resistance. Image and colour analyses have the ...ability to obtain many image parameters and to discriminate between different aspects in plants, which makes them a suitable tool in combination with genetic analysis to study the plants salt tolerance. To the best of our knowledge, there are no publications about the monitoring of halophytic plants by non-destructive methods for identifying the differences between plants that belong to different maternal salinity environments. The aim is to evaluate the ability of image analysis as a non-destructive method and principal component analysis (PCA) to identify the multiple responses of two S. europaea populations, and to determine which population is most affected by different salinity treatments as a preliminary model of selection.
Image analysis was beneficial for detecting the phenotypic variability of two S. europaea populations by morphometric and colour parameters, fractal dimension (FD), projected area (A), shoot height (H), number of branches (B), shoot diameter (S) and colour change (ΔE). S was found to strongly positively correlate with both proline content and ΔE, and negatively with chlorophyll content. These results suggest that proline and ΔE are strongly linked to plant succulence, while chlorophyll decreases with increased succulence. The negative correlation between FD and hydrogen peroxide (HP) suggests that when the plant is under salt stress, HP content increases in plants causing a reduction in plant complexity and foliage growth. The PCA results indicate that the greater the stress, the more marked the differences. At 400 mM a shorter distance between the factorial scores was observed. Genetic variability analysis provided evidence of the differences between these populations.
Our non-destructive method is beneficial for evaluating the halophyte development under salt stress. FD, S and ΔE were relevant indicators of plant architecture. PCA provided evidence that anthropogenic saline plants were more tolerant to saline stress. Furthermore, random amplified polymorphic DNA analysis provided a quick method for determining genetic variation patterns between the two populations and provided evidence of genetic differences between them.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
•An integrate study of mango ripening was carried out by AFM, XRD and CLSM.•Changes on cell wall stiffness during mango ripening were revealed by AFM.•Correlation between Younǵs modulus and RPI has a ...linear fit.•Enzymatic degradation of the mango pectins were elucidated at nanoscale level.•X-ray diffraction and CLSM provided data to use cellulose from mango wastes.
Mango is an important crop worldwide, with a postharvest loss that is huge due to its climacteric behaviour. This study evaluated the softening of Tommy Atkins mangos during the ripening process. Ripening index (RPI) shown a decrease from 9.18 ± 0.14 to 4.75 ± 0.47. The enzymatic activity agreed with physicochemical parameters and with the structural and mechanical changes. Three pectin fractions were isolated from the mango cell wall: water soluble (WSP), chelator soluble (CSP) and diluted alkali soluble (DASP) pectin. The Younǵs modulus (E) of the primary cell wall was evaluated, it decreased from 1.69 ± 1.02 to 0.39 ± 0.16 MPa, which could be attributed to the softening of the fruit. A linear fit correlation between E and RPI was found. X-ray and confocal laser scanning microscopy analysis showed the changes occurred in the mango cell wall structure during maturation. Novelties of current study can be helpful in the use of mango wastes to obtain cellulose.
The use of composite edible films made from biopolymers has attracted interest as a way to reduce pollution and recycling problems; however, the relation between barrier, mechanical and structural ...properties of the films have been scarcely studied. The aim of this work was to evaluate composite zein–chitosan edible films by applying common nanotechnology tools and to relate the results to zein concentration and film structural changes. Rougher, more elastic, and less hard film structures with better water vapour barrier properties were obtained using larger zein concentrations. Raman spectroscopy exhibited unexpected interactions, as indicated by the disappearance of the thiol groups of cysteine in the zein films and the appearance of OSO and COS groups in the blended materials in conjunction with the disappearance of zein ɛ-amino and NH2 functional groups in the zein film samples, thereby confirming changes in the blended film structure. Zein concentration presented linear correlations with water vapour permeability (R=−0.978) and film roughness (R=0.929). The composite films presented better barrier and mechanical properties than single ingredient films. This information shows the benefit of using protein–polysaccharide blends to prepare edible films.
Edible films (EFs) have gained great interest due to their ability to keep foods safe, maintaining their physical and organoleptic properties for a longer time. The aim of this work was to develop ...EFs based on a chitosan-zein mixture with three different essential oils (EOs) added: anise, orange, and cinnamon, and to characterize them to establish the relationship between their structural and physical properties. The addition of an EO into an EF significantly affected (
< 0.05) the a* (redness/greenness) and b* (yellowness/blueness) values of the film surface. The EFs presented a refractive index between 1.35 and 1.55, and thus are classified as transparent. The physical properties of EFs with an added EO were improved, and films that incorporated the anise EO showed significantly lower water vapor permeability (1.2 ± 0.1 g mm h
m
kPa
) and high hardness (104.3 ± 3.22 MPa). EFs with an added EO were able to inhibit the growth of
sp. and
sp. to a larger extent than without an EO. Films' structural changes were the result of chemical interactions among amino acid side chains from zein, glucosamine from chitosan, and cinnamaldehyde, anethole, or limonene from the EOs as detected by a Raman analysis. The incorporation of an EO in the EFs' formulation could represent an alternative use as coatings to enhance the shelf life of food products.
•Salicornia seed’s oil show good yield as biofuel and edible oil source.•Cellulose in Salicornia biomass is a good source for bioethanol production.•Emerging Salicornia trends in food, ...pharmaceuticals and cosmetics must be driven.•Salicornia has health and nutraceuticals benefits in its bioactive compounds.•Salicornia biofiltering and phytoremediation are important-economic uses in ecology.
Salicornia is a genus of plants that are able to grow in saline conditions and that are known as “halophytes”. Moreover, this species has plenty of other industrial and ecological applications as a sustainable crop. Currently, there are many publications on plants with a high economic value, but few are related to the applications of high salt-tolerant plants as an important source for the food, pharmacy, bioenergy and ecology sectors. Aspects such as morphology, microstructure-composition, salt-adaptation mechanism are discussed to improve our understanding of these elements with regard to scale its production while its commercial exploitation depends on better knowledge of its structure and composition. A summary of its biomass, seeds, oil and ethanol yields is then presented to highlight its profitability as a sustainable crop. Furthermore, ecological applications in aquaculture and phytoremediation are also discussed, while applications in food, pharmacy, ecology, chemical and cosmetic sectors are also presented. In this review, Salicornia stands out in the fields of food and pharmacy due to its bioactive compounds which have been reported to have antioxidative and anti-inflammatory health benefits as well as immunomodulatory activities, and can also be used as secondary metabolites in pharmaceutics or as nutraceutics in food, with high commercial and culinary value as salt substitute due to its protective effect on vascular dysfunction and hypertension. The second aspect that is emphasized is its seed oil content, with a 30 % edible oil rich in linoleic, oleic, palmitic and stearic acids, along with a high protein content. It is also mentioned that Salicornia’s seed oil and biomass have been reported as good sources for biofuel and bioethanol production. Chemically, some studies have reported antipathogenic effects among others from Salicornia nanoparticles. Recommendations on how to increase its growth through the association of plant growth promoting bacteria, new application trends, the difficulties that need to be overcome with a proposal study cost and benefits of Salicornia farm associated with aquaculture as well as the main nutritional and/or productivity effects based on the cultivation methods, are discussed.
•Size, cell shape and cellular architecture of mesocarp tissue control apple firmness•Stiffness and complexity of cell wall were the main biomechanics of apple tissues•Cellulose fibers and pectic ...agglomerate size explain some differences in apple firmness•Principal component analysis was successful in classifying the studied apple cultivars.•A simplified model for firmness prediction of some apples was obtained by multivariate analysis
A study of the physicochemical, structural, nanomechanical properties at macro, micro and nanometric scales was carried out to determine which features have the greatest influence on the firmness of selected apple cultivars (Golden Delicious, Granny Smith, Gala and Red Delicious). Physicochemical assays, microscopy techniques, image analysis, nanoindentation and spectroscopy were used to characterize the properties of the four selected apples. The data were analyzed using principal component analysis, Pearson analysis and multiple linear regression to classify apple cultivars. These techniques were also used to identify which physicochemical, micro, and nanostructural as well as nanomechanical features were most associated with apple firmness. This allowed for the creation of a mathematical model (R2 = 0.97) for the prediction of apple firmness from evaluated variables. It was determined that the cellular architecture, stiffness of cell walls and crystallinity index of cellulose fibers were the most important factors in explaining the variability of firmness in the studied apples. This research provides novel and valuable information for understanding the role of cellular architecture, micro and nanostructure, as well as nanomechanical properties in the firmness of the studied cultivars.
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•Optimal conditions of oil extraction by thermosonication were found by RSM.•Thermosonication extraction improved oil yield and its quality was preserved.•Amplitude increase cause ...microstructural changes and reduce the crystallinity index•Structural changes in the residual cake caused by thermosonication were evidenced.
The seed of Ricinus communis L. is a source of oil that can be used to produce biodiesel. In this study, the thermosonication (TS) extraction of castor oil is proposed and is compared with Soxhlet (S) extraction as the conventional method. The optimum conditions for the TS extraction of castor oil were determined by response surface methodology (RSM). The time at 25, 35, and 45 min and amplitudes of 25, 50, and 75% were independent variables, while the dependent variables were the oil yield, iodine index, peroxide index, saponification index, unsaponifiable matter, acidity index, and refraction index. The optimal conditions for the oil yield were an amplitude of 50%, 35 min, and a solid/liquid ratio of 1/10 g/mL; a yield of 61.12% was reached under these conditions; by S extraction, the yield was 57.3% after 8 h of extraction. The microstructure of the residual cake before and after extraction was evaluated by scanning electron microscopy and the cellulosic compounds, proteins, and lipids in the residual cake were identified and their distribution observed by means of confocal laser scanning microscopy. Microscopy techniques and image analysis were helpful in evaluating the changes in the microstructure that occur on the residual cake during the TS and S extraction and to understand the extraction mechanisms. The crystallinity index was calculated from X-ray diffraction spectra to interpret changes in the structure of the residual cake before and after use of the extraction methods. Therefore, the TS extraction improved the oil yield in shorter extraction time. Characterization of the residual cake opens the way to study a potentially usable material as a source of cellulosic compounds.
A description of morphological changes of particles along spray drying was carried out by means of scanning electron and light microscopy. Samples of atomized material (40% maltodextrin solution) ...were withdrawn during drying from a laboratory spray drier at various vertical distances from the atomizing nozzle, photographs of these materials were taken and images analyzed for detecting processes such as crust formation, inflation and shrinking. Final product was analyzed by SEM, mean size of particles determined and fractal dimension of projected perimeter was evaluated by means of the box counting method. This parameter of particles allowed for distinguishing between irregular and smooth contours of final powders. It was possible to explore qualitative relations of morphology and moisture content of particles with air drying temperatures along the actual drying operation, especially those related to breakage and inflation (intermediate and high drying temperatures) and with collapse (low-temperature drying).
The pollution caused by use of petroleum-derivate plastic materials is a major environmental problem. This has encouraged researchers to develop new compostable and environmental-friendly materials ...based on biopolymers and agro-industrial residues. The aim of this work was to study the addition of garlic skin (GS) particles and the changes in physicochemical, mechanical, and microstructural properties of films formulated with potato starch and gellan gum as well as the creation of an environmentally friendly dish. Different concentrations (1, 2 and 3% w/v) and sizes (1410-213 μm, 212-39 μm and 38-1 μm) of GS particles were used for the mechanical reinforcement of the films and as independent variables of the experimental design. Different response variables (phenolic content, color difference, thickness, film transparency, stress, strain, Young's modulus, water solubility, water adsorption capacity, fractal dimension and entropy of the images) were evaluated to select the optimal point using response surface methodology (RSM). Microscopy techniques and texture image analysis were used to explain the effect of adding GS particles to the microstructure and mechanical reinforcement of the films. Moreover, thermogravimetric analysis (TGA), principal component analysis (PCA) and RSM were used to select the best film for making a compostable dish using a low-cost molding process at laboratory level. A novelty of this study was proposing an alternative use of GS waste in a film with biopolymers, integrating different analytical tools to facilitate the selection of the suitable formulations to create compostable dishes in 60 days, which goes beyond the traditional studies of coatings and polymeric films reported.
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•Garlic skin (GS) particles were useful to mechanically reinforce biodegradable films.•Thermogravimetric and multivariate analysis were successful in selecting the most appropriate films.•Particle size/concentration of GS significantly affects film microstructure and mechanical properties.•Medium size particles and concentration improve mechanical and microstructural properties of films.•3D-printing and molding process were successful for the development of compostable dishes.
The objective of this study was to evaluate the effect of the presence of calcium oxalate (CaOx) crystals on the micromechanical properties of sclerenchyma tissue from the pecan nutshell (Carya ...illinoinensis). The microstructure of the cross-section nutshell was examined using light microscopy (LM) and atomic force microscopy (AFM). Using an instrumented indentation system, indentation tests with maximum loads of 500 mN were made on the biological material where the variables studied were the number of crystals present in the evaluated area and the size of individual crystals. Microscopic analysis revealed that the pecan nutshell consists of sclerenchyma tissue with multiple CaOx crystals randomly distributed throughout the material, exhibiting prismatic shapes and various sizes. The results of the indentation tests showed that the examined areas where there were crystals (1, 2 or up to 3) presented values of hardness and elastic modulus significantly higher (P < 0.05) compared to the sclerenchyma (without crystals). Likewise, there were no significant differences (P > 0.05) between the values of the micromechanical properties of the areas evaluated as a function of the number of crystals. On the other hand, it was observed that the size of the crystals did not show a direct correlation with the mechanical properties evaluated as expected. In conclusion, the biomineralization phenomenon is a successful strategy designed by nature to improve the rigidity of the pecan nutshell, where the CaOx crystals strengthen the structure by increasing the micromechanical properties.
•The effect of CaOx crystals on the micromechanical properties of the sclerenchyma from the pecan nutshell were evaluated by indentation tests.•The CaOx crystals increased the hardness (≈20%) and elastic modulus (≈13%) of the sclerenchyma tissue locally.•There were no significant differences between the values of the micromechanical properties evaluated as a function of the number of crystals.•The size of the crystals did not show a direct correlation with the mechanical properties.•CaOx crystals strengthen the structure of the pecan nutshell, demonstrating that they fulfill a mechanical function.
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