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In the present work, an alternative value aggregation to the residues from the industrialization of tilapia is suggested by extraction of chondroitin sulfate from the bones of the spine. Resulting materials were chemically characterized by thermogravimetry (TGA/DSC), infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). Through the characterization of CS, it was possible to conclude that the methodology used to extract it generated a product with high thermal stability and purity. [ABSTRACT FROM AUTHOR]

CO 2 is an important gas for the biological cycle, as it plays a fundamental role in regulating the planet's temperature. Modifications in ecosystems promote an imbalance in carbon dynamics, causing more significant release into the atmosphere. The Caatinga biome, a dry forest type, has been anthropized since before the beginning of Brazil's colonization. Knowledge about the consequences of this anthropization in carbon stock changes in the soil is still scarce. This work aimed to evaluate the soil CO 2 efflux in preserved and degraded sites in the Caatinga. CO 2 emissions were collected in the field using an Infrared Gas Analyzer at four sampling points in the dry and rainy seasons of 2017. Texture, reactivity, nutrient content, and soil porosity were measured. Base saturation and texture were similar in the preserved and degraded sites. Preserved sites have higher C, N, P, and available water contents. Emission of CO 2 increased with available water after rain events. Temperature, soil moisture, and land use influenced CO 2 efflux, indicating the complexity of understanding the phenomenon. Degraded sites registered lower C stock and CO 2 influx as an indication of desertification. • FCO 2 was monitored in preserved and degraded sites in the driest region of Brazil. • Degraded sites registered influx of CO 2 as indicative of desertification. • Deforestation, soil fertility and emission of CO 2 are linked. [ABSTRACT FROM AUTHOR]

Abstract: Hydrocolloids from seaweeds have interesting functional properties, such as antioxidant activity and gelling ability. A polysaccharide was isolated by aqueous extraction at 90°C from the red seaweed Gracilaria birdiae (Gb), with a yield of 27.2% of the seaweed dry weight. The sulfate content of the polysaccharide was 8.4% and the main sugars present were galactose (65.4mol%), 3,6-anhydrogalactose (25.1mol%) and 6-O-methylgalactose (9.2mol%). Gel permeation chromatography showed that Gb polysaccharide is a heterogeneous system, with molar mass at the main peak of 3.7×105 gmol−1 and a shoulder of 2.6×106 gmol−1. The sulfated polysaccharide of Gb characterized by FTIR exhibits the characteristic bands of agarocolloids (at 1375 and 770cm−1). The rheological behavior of Gb sulfated polysaccharide exhibits a gel-like behavior close to the one observed in commercial agar. The antioxidant properties of Gb sulfated polysaccharide were evaluated by measuring DPPH free-radical scavenging effect, showing that this polysaccharide has a moderate effect in inhibiting the formation of those radicals. [Copyright &y& Elsevier]

Abstract: The aim of this work was to evaluate the influence of glycerol and corn oil on physicochemical properties of polysaccharide-based films. The polysaccharides used were galactomannan from Gleditsia triacanthos and chitosan. Fourier-transform infrared spectroscopy, differential scanning calorimetry and thermogravimetric analysis were performed, together with determinations of moisture content, solubility, water vapor permeability and mechanical properties. Structure–properties relationships were established, relating the two polysaccharides’ structures with the way they interact with water, other film’s constituents (glycerol and oil) and the resulting properties. The presence of glycerol and corn oil originated a more hydrophilic structure and a decreased affinity of the film matrix to water, respectively, in both polysaccharides. However, the two polysaccharides presented different behaviors in terms of glass transition temperature, water vapor permeability and elongation-at-break that have been related with the particularities of their structure: while for the galactomannan the specific sorption sites for water are the O–H groups, for chitosan those are O–H and/or NH2 groups. The present work provides insight regarding the physicochemical properties of polysaccharide-based films and established relationships with polymers’ structure, showing that the two polysaccharides studied here have adequate properties to be used as packaging materials for specific food applications. [Copyright &y& Elsevier]

Abstract: Galactomannans of Gleditsia triacanthos, Caesalpinia pulcherrima and Adenanthera pavonina were structurally and thermally characterized. Methylation analyses confirmed that these three galactomannans are composed by a 4-linked mannose polymer with galactose side chains attached at the C6 position. G. triacanthos galactomannan had an estimated average degree of polymerization of 224 mannose residues, with a degree of branching of 0.24, C. pulcherrima galactomannan had a degree of polymerization of 252 and a degree of branching of 0.30, and A. pavonina galactomannan had a degree of polymerization of 475 and a degree of branching of 0.60. Enzymatic hydrolysis with endo-β-mannanase and the subsequent analyses of the low molecular weight fraction by ESI-MS/MS indicated the presence of characteristic structural features of galactomannans. Furthermore, acetyl and pentosyl residues were detected in the galactomannan of G. triacanthos and analyses of higher molecular weight fractions from G. triacanthos were performed, confirming that presence. Differential scanning calorimetry (DSC) showed the presence of two peaks related with water loss, confirmed by thermogravimetric analysis (TGA). The different compositions of galactomannans with different mannose content and different molecular weights influence their thermal behaviour. A higher content of mannose lead to higher values of the enthalpy change (first thermal transition) and glass transition temperature (T g ), while the enthalpy change of the second thermal transition was influenced by the viscosity average molecular weight (Mv) of the samples. This work provides understanding of structural and thermal properties of three galactomannans from non-conventional sources, thus contributing to a better insight on their possible food, pharmaceutical or biomedical applications. [ABSTRACT FROM AUTHOR]

Abstract: In this work, three different extraction procedures were performed in Gleditsia triacanthos seeds in order to obtain extracts that were characterized in terms of the yield of extraction, total phenolic content and antioxidant properties. The extracts have been shown to contain considerable amounts of phenolic compounds (between 4.93 and 12.34mggalicacid gextract − 1) and antioxidant activity between 18.77 and 71.59%. Different concentrations of one of the extracts (extract presenting simultaneously the best values of total phenolic content, radical scavenging activity and the concentration of the compounds that caused a 50% inhibition of the radical scavenging activity) were incorporated into G. triacanthos galactomannan solutions and films were cast from these. A 22 full factorial design was done to evaluate the effect of the galactomannan and extract concentrations in film properties. Galactomannan concentrations ranging from 0.5 to 1.5% and extract concentrations ranging from 0 to 1.0%, were used and the evaluated film properties as: water vapour permeability, colour, total phenolic compounds content and antioxidant activity. This work has shown that G. triacanthos can be used not only as a source of galactomannan films suitable to incorporate antioxidant compounds for further application in the food industry but also as a source of the active compounds to be incorporated. [ABSTRACT FROM AUTHOR]

• Ancient anthropic influence in Caatinga is detectable by soil properties. • Anthrosol in Caatinga are contemporaneous of Amazonian Dark Earth. • Ca2+ and P contents are responsible for organic carbon stabilization in Anthrosols. Multiple waves of dispersion populated South America throughout the late Pleistocene and early Holocene. The oldest rock art and artifacts in Caatinga are dated from 10,000 BP. Besides that, there is no register of ancient activities in soils in Caatinga. Four pedons were taken, described and classified in sites with a high number of artifacts littering the surface and/or rock art. Five more pedons were described to represent soil without anthropic influence. Soils are shallow and transition between horizons was predominantly clear or abrupt. Anthrosols in Caatinga have value and chroma similar to the anthropic horizons described in Amazonian dark earths. The pedons are strongly acid to slightly alkaline and predominantly have base saturation above 50% in all horizons. Anthrosols in Caatinga have up to 6 and 544 times, respectively, more soil organic carbon and phosphorus compared to adjacent soils without anthropic influence. Besides illite and kaolinite, apatite and calcite compose the clay and silt fractions and confirm the human influence in soil formation. Radiocarbon and thermoluminescence dating indicate that Anthrosols in Caatinga are contemporaneous to the majority of Amazonian dark earths. [ABSTRACT FROM AUTHOR]

Hyaluronic acid (HA) is a biopolymer of enormous value aggregation for in general industry. The vitreous humor of the eyeball from Nile tilapia contains appreciable amounts of hyaluronic acid. In this sense, the aim of this work was to extract and characterize hyaluronic acid from the eyeball of the Nile tilapia for biomedical applications, adding value to fish industry residues. The characterization by infra-red (FTIR), 13C nuclear magnetic resonance (NMR) and high performance liquid chromatography (HPLC) confirmed that hyaluronic acid was obtained. The gel permeation chromatography (GPC) showed that the obtained material presents a low molecular mass (37 KDa). Thermogravimetry (TGA), differential scanning calorimetry (DSC), X-ray diffraction (XRD) analysis showed that the materials present a thermal stability superior to the commercial hyaluronic acid from Streptococcus equi , with a partially crystalline character. The cytotoxicity assay (MTT method) with fibroblast cells (L929) demonstrated that the extracted biopolymer besides not being cytotoxic, was able to stimulate cell proliferation. Therefore, the hyaluronic acid extracted from this source of residue constitutes a product with biotechnological potential, which has adequate quality for wide biomedical applications. [Display omitted] • HA of low molecular mass (37 KDa) was isolated of the eyeball Nile Tilapia. • HA was confirmed and characterized with FTIR, 13C NMR and HPLC. • The contents of carbon, hydrogen, nitrogen and sulfur were revealed. • Extracted HA was able to stimulate cell proliferation in fibroblast cells. • Extracted HA is a product with adequate quality for wide biomedical applications. [ABSTRACT FROM AUTHOR]

Abstract: Polysaccharide multinanolayers are becoming a new and general means of modifying and functionalizing surfaces of several materials. This is achieved through changing the interfacial properties of those surfaces followed by sequential adsorption of e.g., polysaccharides. Knowledge of properties of polysaccharide solutions such as zeta potential (Zp) and mean hydrodynamic diameter (Z-average) is crucial to obtain stable, functional nanostructures. In this work sodium alginate, carragennan, chitosan, and two galactomannans were characterized in terms of Zp and Z-average, as a function of polysaccharides and NaCl concentrations and pH. The most relevant effects of these factors on Zp and on Z-average were analysed using a 23 full factorial design. With a few exceptions, the effect of independent variables on Zp and Z-average values is statistically significant. In general (except for k-carragennan solutions) higher polysaccharide concentrations lead to higher Z-average values; and higher pH values lead to higher Z-average values (except for solutions of chitosan and galactomannan of Gleditsia triacanthos). NaCl addition decreases Z-average. For the galactomannans solutions Zp values were found to be neutral (ranging from −13.7 to −2.1mV) independently of the combinations of variables used. This work establishes a relationship between important polysaccharides properties and the values of pH, polysaccharide and salt concentrations, thus providing insight on how to control the structure and texture of multinanolayered films in view of their potential application e.g., in the food, pharmaceutical, and cosmetic industries. [Copyright &y& Elsevier]

Abstract: Nanoemulsions of β-carotene were prepared using a high-energy emulsification–evaporation technique based on a 23 level factorial design. Results show that it is possible to obtain dispersions at a nanoscale range. Process parameters such as time and shear rate of homogenization affected significantly particle size distribution in terms of volume-weighted mean diameter and surface-weighted mean diameter. The obtained nanoemulsions presented a volume-surface diameter ranging from 9 to 280nm immediately after the production of particles, displaying in all cases a monomodal size distribution. Those nanoemulsions showed a good physical stability during 21days storage. The stability was evaluated by the maintenance of size distribution. However, β-carotene retention inside the micelles and color were affected by storage. Processing conditions also influenced storage stability. [ABSTRACT FROM AUTHOR]

Abstract: Nanolaminates have been reported to have applications in different areas, such as the preparation of multilayer films, coating biomedical appliances or multilayer edible coatings with enhanced properties for applications in the food industry. This work aims at characterizing the surface properties, water vapor permeability, and thermal and mechanical properties of a nanolayered film. The film was produced using two polysaccharides with opposite charges, chitosan and sodium alginate deposited on to aminolyzed/charged PET. Contact angle measurements showed differences in the films with a successively higher number of layers. SEM images allowed the measurement of the thickness of the layers. The nanolayered film had a water vapor permeability of (0.85±0.04)×10−11 gm−1 s−1 Pa−1 and a hardness increase of 0.245±0.06GPa. DSC and TG analyses of the nanolayered film showed increases of 39.2% in the melting energy when compared with the PET film used as support, and a decrease in the decomposition temperature from 386 to 331°C. [Copyright &y& Elsevier]

Abstract: The objective of this work was to produce new edible coatings, based on a mixture of galactomannans from novel sources (seeds of Adenanthera pavonina and Caesalpinia pulcherrima), collagen and glycerol, and to determine their influence in gas transfer rates when they are applied on mangoes and apples. The first part of the work consisted in obtaining coating solutions with the convenient values of wettability for each fruit; such coating solutions were then characterized in terms of their permeability (to CO2, O2 and water vapour), mechanical properties, colour and opacity. Gas transfer rates from mangoes coated with a solution of A. pavonina galactomannan (0.5%), collagen (1.5%) and glycerol (1.5%) were compared with those of mangoes without coating: 28% less O2 consumption and 11% less CO2 production were observed in coated mangoes. The same procedure was performed in apples (in this case using C. pulcherrima galactomannan (0.5%), collagen (1.5%) and no glycerol); the CO2 production and the O2 consumption was approximately 50% lower in apples with coating than in apples without coating. The results suggest that these coatings can reduce gas transfer rates in these fruits, and can be therefore important tools to extend their shelf life. [Copyright &y& Elsevier]

Abstract: The effect of the concentrations of the polysaccharide from Anacardium occidentale L. (Policaju) and a surfactant (Tween 80) on relevant properties of edible coatings/films, in view of their application on apples (cv. Golden) was evaluated. The influence of the interactions between those two constituents on apples’ surface properties and on the coating/film’s wettability, water vapor permeability, opacity and mechanical properties was evaluated. The effects of the studied variables (polysaccharide and surfactant concentrations) were analyzed according to a 22 factorial design. Pareto bar charts were used to understand the most significant factors on the studied properties. The addition of surfactant reduced the cohesion forces, therefore reducing the surface tension and increasing the wettability; this resulted in an improved compatibility between the solution and the fruit skin surface. The opacity was also reduced. The results of each of the analyzed properties were adjusted to a polynomial, multifactor model, which provided a good fitting accuracy. This model is important once it will reduce the characterization work needed in subsequent applications of these coatings/films on foods. [Copyright &y& Elsevier]

Abstract: This work presents a methodology for the extraction of galactomannans from seeds of four different species of Leguminosae (Adenanthera pavonina, Caesalpinia pulcherrima, Gleditsia triacanthos and Sophora japonica) to be used e.g. in the food and biomedical industries. The galactomannans were obtained by aqueous extraction followed by a precipitation with ethanol. This methodology is simpler and easier to perform than other existing extraction and purification methodologies, and because it avoids the use of organic solvents (other than ethanol), it is able to generate food grade substances and is environmentally friendlier. The yield of extraction in different stages of the process, monosaccharide composition, as well as physical and chemical parameters of the isolated galactomannans were determined and compared with previously published results. The mannose/galactose ratio of the extracted galactomannans ranged from 1.35 (A. pavonina) to 5.75 (S. japonica). The intrinsic viscosity ranged from 11.34dL/g (C. pulcherrima) to 8.74dL/g (S. japonica), while the viscosity average molecular mass ranged between 1.81×106 Da and 1.17×106 Da (A. pavonina > C. pulcherrima > G. triacanthos > S. japonica). The results confirm the suitability of the extraction and purification procedure to obtain galactomannans from non-traditional sources. [Copyright &y& Elsevier]

Abstract: Water soluble polysaccharide from Gracilaria birdiae cultivated along the northeast coast of Brazil was characterized by infrared (FT-IR) and nuclear magnetic resonance (NMR) spectroscopy. The composition of the polysaccharide in wt% was determined as: β-d-galp (50.3%), 3,6-anhydro-α-l-galp (40.5%) and -α-l-galp-6 sulfate (9.2%). The ratio of l/d units (β-d-galp units and 3,6-anhydro-α-l-galp +α-l-galp-6 sulfate) is that of an ideal agarose. The sulfate content calculated by S% accounts for 6.4%. 1D and 2D NMR techniques were employed in order to assign the spin system of polysaccharide without partial degradation. The structure is composed of →4-3,6-anhydro-α-l-galp (1→3)β-d-galp 1→segments, with the possibility of a α-l-galp unit substituted at the 6-position by sulfate ester. [Copyright &y& Elsevier]

In this study, nanoemulsions of essential oil from Ocimum gratissimum (Linn) (EO) were produced using low and high energy techniques using cashew gum (CG) as a co-surfactant. The main constituents of the EO were determined by Gas Chromatography coupled with Mass Spectrometry (GC–MS), and their presence in the EO and in the formulations verified by Fourier Transform Infrared Spectroscopy (FTIR) and UV–visible spectrophotometry was observed the encapsulation efficiency (EE%), with colloidal stability. Nuclear magnetic resonance (NMR) was used to study cashew gum. Dynamic light scattering analysis (DLS) determined the nanoemulsion Z means, polydispersity index and the Zeta potential value, nanoparticle tracking analysis (NTA) were determined. The nanostructured EO showed better antibacterial action against the pathogenic gastroenteritis species Staphylococcus aureus , Escherichia coli and Salmonella enterica when compared to free EO. Atomic Force Microscopy (AFM) was used for morphological analysis of the nanoparticle and study of the action of the nanoemulsion through images of the cellular morphology of S. enterica. The antioxidant activity was evaluated against the ABTS radical (2,2′-azino-bis diazonium salt (3-ethylbenzothiazoline-6-sulfonic acid)). The encapsulation of EO in a nanostructured system improved its antibacterial and antioxidant activity, the low energy synthesis showed greater storage stability, remaining stable for 37 days. [Display omitted] • Low cost O/W nanoemulsion with preservative potential for the food industry. • Nanoemulsion improves the antibacterial and antioxidant activity of essential oil. • The nanoemulsion antibacterial action of alters the bacterial surface. • The nanoemulsion enhanced the antioxidant activity of O. gratissimum. [ABSTRACT FROM AUTHOR]

Abstract The present study aimed to characterize the surface properties of Nile tilapia (Oreochromis niloticus) fillets and evaluate the wettability properties of edible coatings based on chitosan and gelatin from fish scales on its surface using varying concentrations of biopolymers and plasticizer. The surface of Nile tilapia fillet was characterized as low-energy with a surface tension of 63.80 mN/m, whose polar and dispersive components were 49.98 mN/m and 13.82 mN/m, respectively. From the 32 experimental design it was observed that the increase of the chitosan concentration leads to higher values of the adhesion coefficient but results on a decrease of the spreading coefficient. For gelatin coatings, the biopolymer concentration was found to both decrease the adhesion and spreading coefficients. However, the use of higher plasticizer concentrations decreased the values of adhesion and spreading coefficients for the chitosan coatings while increases the values for the gelatin coatings. Preliminary characterization revealed that the best experimental spreadability coefficients (Ws) were −13.565 mN/m for the chitosan coatings and −10.762 mN/m for gelatin coatings. Highlights • The surface of Nile tilapia fillet were characterized as low-energy. • The increase in the biopolymer concentration decreased the spreading coefficient. • The glycerol concentration showed the opposite effect on wettability of coatings. [ABSTRACT FROM AUTHOR]

Protein–polysaccharide conjugates often display improved techno-functional properties when compared to their individual involved biomolecules. α-Lactalbumin:acacia gum (α-la:AG) conjugates were prepared via Maillard reaction by the dry-heating method. Conjugate formation was confirmed using results of absorbance, o -phthalaldehyde test, sodium dodecyl sulfate–polyacrilamide gel electrophoresis (SDS–PAGE) and size exclusion chromatography. Techno-functional properties (emulsifying characteristics, solubility, and thermal stability) were evaluated for α-la, α-la/AG mixtures and α-la:AG conjugates. Conjugate thermal stability was improved compared to pure α-la treated at the same conditions of conjugate formation. Response surface methodology was used to establish models to predict solubility and emulsifying activity as functions of the salt concentration, pH and reaction time. α-la:AG conjugate solubility is affected in a complex manner by the three factors analyzed. Emulsifying activity index (EAI) of α-la is significantly affected by pH, while the α-la:AG EAI is affected by the three analyzed factors. Both solubility and EAI are maximized with pH 8.0, NaCl concentration of 0.3 mol L −1 and two days of Maillard reaction. [ABSTRACT FROM AUTHOR]

Abstract: The development of mixed systems, formed by locust bean gum (LBG), and κ-carrageenan (κ-car) can offer new interesting applications such as the development of edible films with particular properties. κ-car/LBG blend films with different ratios were developed, and their effects on films’ physical properties were assessed. Thermogravimetric analysis (TGA), X-ray diffraction (XRD) patterns, dynamic mechanical analysis (DMA) and Fourier-transform infrared (FTIR) spectroscopy techniques were used to highlight the interactions between the two polysaccharides. The addition of κ-car to LBG improved the barrier properties of the films leading to a decrease of water vapor permeability (WVP). Improved values of elongation-at-break (EB) were registered when the ratio of κ-car/LBG was 80/20 or 40/60 (% w/w). Moreover, the κ-car/LBG blend films enhance the tensile strength (TS) compared to κ-car and LBG films. FTIR results suggested that hydrogen bonds interactions between κ-car and LBG have a great influence in films’ properties e.g. moisture content, WVP. Therefore, different κ-car/LBG ratios can be used to tailor edible films with enhanced barrier and mechanical properties. [Copyright &y& Elsevier]

Abstract: The objectives of this work were to determine the influence of the application of two different coatings (galactomannan and chitosan) and of storage temperature on the gas exchange rate of “Regional” cheese; subsequently, the coating that showed the greatest influence on the cheese gas exchange and simultaneously decreased the O2 consumption and the CO2 production rates was applied on cheese, being the shelf-life parameters monitorized through the performance of chemical and microbiological analyses. Both coatings caused a reduction of and of the cheese (between 0.19- and 1.30-fold for and between 0.19- and 1.50-fold for , depending on the temperatures). The cheese coated with the galactomannan coating was the one with the lower values of (between 0.195 and 0.635mL kg−1 h−1) and (between 0.125 and 0.900mL kg−1 h−1). Temperature was also found to have an important effect on and , its influence being well described by an Arrhenius equation with coefficients of determination, R 2, of 0.85 and above. The chemical and microbiological analyses showed that the application of the coating in cheese samples can be used to decrease the water loss and the colour changes during the storage time. The presence of the coating decreased the moisture loss of the cheese in 2.5% and 1.9%, and the weight loss in 3.8% and 3.1% at 4°C and 20°C, respectively. Also, the hardness of the cheese can be decreased as a result of the interaction of the presence of the coating with changes in the storing temperature. In the studied range (4–20°C) temperature has a statistically significant effect in moisture loss, colour change, hardness and total mesophilic bacterial growth. Overall, galactomannan coating can be used to improve “Regional” cheese shelf-life as it decreases and , improves its weight and appearance and can be used to incorporate natural preservatives to reduce post contamination. [Copyright &y& Elsevier]

The aim of this study was to determine the wetting capacity of a new chitosan source (Ucides cordatus (Uçá-crab)) on quality of frozen serra fillets. First, nine coating solutions were produced using three concentrations of chitosan (1.5%, 2.0%, and 2.5%) and three concentrations of glycerol (0.3%, 0.45%, and 0.6%). Then, the spreading coefficient (Ws) of the coating solutions on the surface of serra fillet was determined. Coating with 2.0% chitosan and 0.60% glycerol produced Ws near to zero, with a value of −11.72 ± 4.56 mM/m. This solution was selected and applied to serra fillet, and the shelf-life at −18 °C was evaluated for 180 days. Coating loss (chitosan and water) and weight loss of the serra fillet were analyzed. During storage, the physicochemical parameters of the fillets (pH, total volatile nitrogen bases, trimethylamine nitrogen, thiobarbituric acid reactive substances) and the microbiological profile were analyzed. The results showed that the chitosan coating produced less loss of coating when compared to the glaze. In addition, the chitosan coating extended the life of the serra fillet when compared to both glaze and control groups. This effect was produced due to lower bacterial growth that generated more suitable physicochemical conditions. Uçá-crab showed to be a suitable source for the production of edible chitosan coating with adequate properties to improve the shelf-life of Serra fillet. • Glycerol improved the adhesion of the coating chitosan over the serra file surface.. • Ws of chitosan coating increased along with the concentration of glycerol. • Protein degradation of fillets with chitosan coatings was lower than other treatments.. • Chitosan showed good antimicrobial activity for psychrotrophic bacteria. [ABSTRACT FROM AUTHOR]