Int J Biol Macromol
December 2024
To deliver their functionality when used in applications, citrus fibers need to be rehydrated. Factors such as chemical composition, structural organization as well as chemical surface composition are known to influence this functionality. Processing and storage conditions can affect these parameters, making it challenging to maintain stable functionality.
View Article and Find Full Text PDFThe impact of a cyclonic (C), an anticyclonic (AC) eddy and transition zone (TZ), which is the area between the two eddies, on acoustic groups representing various mesopelagic organisms, was investigated using a semi-supervised multifrequency classification approach (hereafter, Escore algorithm). The Escore algorithm involved selecting regions of interest (ROIs) within multifrequency (18, 38, 70, and 120 kHz) echograms and classifying into four clusters or echo-classes using Sv differences (Sv18-38, Sv70-38, and Sv120-38). Acoustic densities and diel vertical migration strength varied between the AC, C, and TZ according to the frequency.
View Article and Find Full Text PDFAccelerating rate of human impact and environmental change severely affects marine biodiversity and increases the urgency to implement the Convention on Biological Diversity (CBD) 30×30 plan for conserving 30% of sea areas by 2030. However, area-based conservation targets are complex to identify in a 3-dimensional (3D) ocean where deep-sea features such as seamounts have been seldom studied mostly due to challenging methodologies to implement at great depths. Yet, the use of emerging technologies, such as environmental DNA combined with modern modeling frameworks, could help address the problem.
View Article and Find Full Text PDFCarbohydr Polym
November 2024
Cellulose, an abundant biopolymer in nature as a structural component of plant cell walls, has a native semi-crystalline structure in which the arrangement of amorphous-crystalline domains governs its key properties such as mechanical and physico-chemical properties. The performance of the material in different situations is shaped by molecular mobility, which affects attributes such as mechanical properties, chemical reactivity, and water absorption. Nevertheless, it is difficult to investigate experimentally the structural and dynamic properties of cellulose-rich materials.
View Article and Find Full Text PDFOcean dynamics initiate the structure of nutrient income driving primary producers, and these, in turn, shape the distribution of subsequent trophic levels until the whole pelagic community reflects the physicochemical structure of the ocean. Despite the importance of bottom-up structuring in pelagic ecosystems, fine-scale studies of biophysical interactions along depth are scarce and challenging. To improve our understanding of such relationships, we analyzed the vertical structure of key oceanographic variables along with the distribution of acoustic biomass from multi-frequency acoustic data (38, 70, and 120 kHz) as a reference for pelagic fauna.
View Article and Find Full Text PDFFood Chem (Oxf)
July 2023
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View Article and Find Full Text PDFTropical marine ecosystems are highly biodiverse and provide resources for small-scale fisheries and tourism. However, precise information on fish spatial distribution is lacking, which limits our ability to reconcile exploitation and conservation. We combined acoustics to video observations to provide a comprehensive description of fish distribution in a typical tropical environment, the Fernando de Noronha Archipelago (FNA) off Northeast Brazil.
View Article and Find Full Text PDFAppl Microbiol Biotechnol
August 2021
Yeasts are anhydrobiotes that accumulate large amounts of trehalose, which is involved in the vitrification of the cytoplasm during drastic desiccation. The effect of devitrification, which can be induced by the transient exposure of desiccated yeasts to increased humidity or elevated temperature, on the survival of yeast has been studied. A glass transition temperature (T)/water activity (a) diagram of yeast was constructed based on differential scanning calorimetry analysis.
View Article and Find Full Text PDFThis study proposes the investigation of curcumin encapsulation into Saccharomyces cerevisiae cells through osmoporation as an efficient way of increasing curcumin stability. The influence of three process parameters (cell, ethanol and curcumin concentrations) on the encapsulation process was evaluated, and the obtained biocapsules were characterised for physical and photochemical stabilisation. Results showed that encapsulation efficiency was favoured by the increase of cells/curcumin ratio and ethanol concentration up to 60%.
View Article and Find Full Text PDFTwo cross-sectional studies were performed 2 years apart in French military personnel deployed from France to French Guiana. In 2011, military medical centres in French Guiana reported 40 cases of intestinal parasitism in service members returning from illegal gold mining sites in the rainforest. In 2013, 48 out of 132 service members returning from French Guiana after a 4-month mission had eosinophilia and seven were infected with hookworm.
View Article and Find Full Text PDFThe effect of modulating the gelatinisation extent by hydration (50/50 and 80/20 water to starch ratio) and temperature (65 or 85 °C) on various properties of wheat starch in presence of flavours has been studied. The hydrothermal treatments resulted in samples with different properties. The lowest residual flavour content was found in samples treated at the highest hydration and temperature (85 °C) while the other treatment conditions led to samples with similar residual flavour content.
View Article and Find Full Text PDFLow moisture baked products were investigated with a view to characterising the effect of both formulation and humidity on their physical stability. At the end of the baking process, the samples were in the amorphous state as a result of starch gelatinization and sugar melting. Their thermal properties were analyzed with differential scanning calorimetry and their glass transitions were studied.
View Article and Find Full Text PDFGlass transition is studied through positron annihilation lifetime spectroscopy (PALS) in maize starch matrices containing 10 (batch STS10) and 20 (STS20) w/w% sucrose, as a function of temperature (T) and water content (c(w)). To circumvent important losses of water upon heating while recording the PALS spectra, a new method is developed: instead of a series of measurements of τ(3), the triplet positronium lifetime, at different T, the latter is kept constant and the series relates to c(w), which is left to decrease at a constant rate. Similarly to the changes in τ(3) with T, the τ(3)vs.
View Article and Find Full Text PDFThe triplet state of positronium, o-Ps, is used as a probe to characterize a starch-20% w/w sucrose matrix as a function of temperature (T). A two-step decomposition (of sucrose, and then starch) starts at 440 K as shown by a decrease in the o-Ps intensity (I(3)) and lifetime (τ(3)), the latter also disclosing the occurrence of a glass transition. Upon sucrose decomposition, the matrix acquires properties (reduced size and density of nanoholes) that are different from those of pure starch.
View Article and Find Full Text PDFPhys Chem Chem Phys
November 2009
Ortho-positronium (o-Ps) is used as a probe in positron annihilation lifetime spectroscopy (PALS) experiments, to characterise the behaviour of free volumes in natural starch samples, as a function of temperature (T). Up to about 540 K, the o-Ps intensity, I(3), remains constant at 26.2% while its lifetime, tau(3), is found to increase linearly.
View Article and Find Full Text PDFMolecular mobility is known to be a key parameter in controlling the physical properties of materials and thus their quality and performance. Beyond glass transition related changes, attention should be called to the impact of local motions remaining in the glassy state. Gelatinized waxy maize starch at different sucrose contents (0-20% solids) was equilibrated between 0 and 14% water and sorption isotherms determined at 25 degrees C.
View Article and Find Full Text PDFSpray-dried ethylcellulose microspheres were used as matrices for the encapsulation of a fungal lactase and/or small paramagnetic probes (Tempol or Tempo). Their dissolution in water was studied. Kinetics fitted with the model Q = kt(n) of Korsemeyer et al.
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