519 research outputs found
Development of dried probiotic apple cubes incorporated with Lactobacillus casei NRRL B-442
[EN] This work presents the development of a probiotic dried apple snack consisting of dried apple cubes impregnated with Lactobacillus casei NRRL B-442. Apple cubes were impregnated with probiotic microorganisms and dried under different temperatures (10-60 degrees C), with or without application of ultrasound. The viability of Lactobacillus casei in the dried apple snack was evaluated studying the effects of drying conditions and ultrasound application (as a drying enhancing technology). A mathematical model was developed to predict the drying kinetics and the inactivation of Lactobacillus casei. Drying and microorganism inactivation rates increased with increasing process temperature and with ultrasound application. The concentration of probiotics in the apple snacks was similar to the concentration of microorganisms in commercial probiotic dairy products when the apples were dried at 60 degrees C or when ultrasound-assisted air-drying was applied, thus proving that the production of dried probiotic apple snacks is possible and technically viable.The authors acknowledge the financial support of Generalitat Valenciana (PROMETEOII/2014/005) from Spain, and the financial support and the award of a scholarship of CNPq from Brazil.Rodrigues, S.; Silva, LCA.; Mulet Pons, A.; Carcel Carrión, JA.; Fernandes, FA. (2018). Development of dried probiotic apple cubes incorporated with Lactobacillus casei NRRL B-442. Journal of Functional Foods. 41:48-54. https://doi.org/10.1016/j.jff.2017.12.042S48544
How cellulose stretches:Synergism between covalent and hydrogen bonding
Cellulose is the most familiar and most abundant strong biopolymer, but the reasons for its outstanding mechanical performance are not well understood. Each glucose unit in a cellulose chain is joined to the next by a covalent C–O–C linkage flanked by two hydrogen bonds. This geometry suggests some form of cooperativity between covalent and hydrogen bonding. Using infrared spectroscopy and X-ray diffraction, we show that mechanical tension straightens out the zigzag conformation of the cellulose chain, with each glucose unit pivoting around a fulcrum at either end. Straightening the chain leads to a small increase in its length and is resisted by one of the flanking hydrogen bonds. This constitutes a simple form of molecular leverage with the covalent structure providing the fulcrum and gives the hydrogen bond an unexpectedly amplified effect on the tensile stiffness of the chain. The principle of molecular leverage can be directly applied to certain other carbohydrate polymers, including the animal polysaccharide chitin. Related but more complex effects are possible in some proteins and nucleic acids. The stiffening of cellulose by this mechanism is, however, in complete contrast to the way in which hydrogen bonding provides toughness combined with extensibility in protein materials like spider silk
Chemical and spectroscopic characterization of humic acids extracted from the bottom sediments of a Brazilian subtropical microbasin
International audienceHumic substances (HS) perform a fundamental role in aquatic environments, exhibiting different levels of reactivity in retaining metal ions and organic pollutants. Also, they control the primary production of these ecosystems and act in the carbon sequestering process. In order to improve our understanding vis-à-vis the structural and functional features of HS from aquatic systems, this study aimed to chemically and spectroscopically characterize humic acids (HA) isolated from bottom sediment samples of a stream in a Brazilian subtropical microbasin by elemental analysis, and infrared (FT-IR), ultraviolet and visible (UV-Vis) and solid-state 13C nuclear magnetic resonance (CP-MAS 13C NMR) spectroscopies, thermogravimetry (TG), and scanning electron microscopy (SEM). Although all samples originated from the same environment, the data showed that the HA have distinct chemical and spectroscopic properties, and that the location and characteristics of the sampling points from which the sediments were collected played an important role in the differences observed. Furthermore, vascular plant matter is probably the main contributor to these samples
Fructooligosaccharides integrity after atmospheric cold plasma and high-pressure processing of a functional orange juice
peer-reviewedIn this study, the effect of atmospheric pressure cold plasma and high-pressure processing on the prebiotic orange juice was evaluated. Orange juice containing 7 g/100 g of commercial fructooligosaccharides (FOS) was directly and indirectly exposed to a plasma discharge at 70 kV with processing times of 15, 30, 45 and 60 s. For high-pressure processing, the juice containing the same concentration of FOS was treated at 450 MPa for 5 min at 11.5 °C in an industrial equipment (Hyperbaric, model: 300). After the treatments, the fructooligosaccharides were qualified and quantified by thin layer chromatography. The organic acids and color analysis were also evaluated. The maximal overall fructooligosaccharides degradation was found after high-pressure processing. The total color difference was < 3.0 for high-pressure and plasma processing. citric and ascorbic acid (Vitamin C) showed increased content after plasma and high-pressure treatment. Thus, atmospheric pressure cold plasma and high-pressure processing can be used as non-thermal alternatives to process prebiotic orange juice
Goats in a comfortable and stressed environment consuming saline water: performance, digestibility, nitrogen balance, and urinary mineral concentrations
ABSTRACT The objective was to evaluate the effect of water salinity and environmental temperature on the nutrient consumption, digestibility, nitrogen balance, and mineral excretion of creole goats. Thirty-six males with an average age of 5.0±0.6 months and an average weight of 20.0±2.3kg were housed in metabolic cages. They are distributed in a completely randomized design, with a 2×3 type crossover (2 temperatures (T1 = 26±0.6ºC and T2 = 32±1.2ºC) and three levels of salinity (1.0, 6.0, and 12.0 dS m-1). The temperature influenced (P0.05) of temperatures or water salinity levels; the animals consumed and retained averages of 10.31 and 4.19 g day-1 of nitrogen in the body, respectively. The different water salinity levels influenced (P<0.05) water intake and increased the excretions of potassium and sodium in urine. Total solids levels ranging from 640 to 9,600mg L-1 in water for goats increase water consumption, as does urine potassium and sodium excretion in urine
Nutritional and mineral composition of Opuntia stricta Haw: Balance of macrominerals, renal function and blood metabolites in sheep
ABSTRACT This study aimed to evaluate the effect of the inclusion of spineless cactus (Opuntia stricta Haw) in the diet of sheep on the balance of macrominerals, renal function, and blood metabolites. Five sheep cannulated in the rumen (61.5±9.5kg body weight) were used in a 5 × 5 Latin square composed of five diets and five experimental periods. The experimental period lasted 105 days, with five periods of 21 days each. Four diets containing levels of spineless cactus (121, 245, 371, and 500g/kg of dry matter (DM)), and a control diet were evaluated. Samples of the ingredients, orts, feces, urine, and blood were collected. Spineless cactus inclusion in sheep diets increased the DM intake, ash, oxalate, and all macrominerals intake (P 0.05). It is possible to verify that the inclusion of spineless cactus, up to the level of 500g/kg of DM in the sheep diets, does not appear to cause damage to the animal’s health. Its inclusion does not compromise kidney function or blood metabolites evaluated herein
Fitting the integrated Spectral Energy Distributions of Galaxies
Fitting the spectral energy distributions (SEDs) of galaxies is an almost
universally used technique that has matured significantly in the last decade.
Model predictions and fitting procedures have improved significantly over this
time, attempting to keep up with the vastly increased volume and quality of
available data. We review here the field of SED fitting, describing the
modelling of ultraviolet to infrared galaxy SEDs, the creation of
multiwavelength data sets, and the methods used to fit model SEDs to observed
galaxy data sets. We touch upon the achievements and challenges in the major
ingredients of SED fitting, with a special emphasis on describing the interplay
between the quality of the available data, the quality of the available models,
and the best fitting technique to use in order to obtain a realistic
measurement as well as realistic uncertainties. We conclude that SED fitting
can be used effectively to derive a range of physical properties of galaxies,
such as redshift, stellar masses, star formation rates, dust masses, and
metallicities, with care taken not to over-interpret the available data. Yet
there still exist many issues such as estimating the age of the oldest stars in
a galaxy, finer details ofdust properties and dust-star geometry, and the
influences of poorly understood, luminous stellar types and phases. The
challenge for the coming years will be to improve both the models and the
observational data sets to resolve these uncertainties. The present review will
be made available on an interactive, moderated web page (sedfitting.org), where
the community can access and change the text. The intention is to expand the
text and keep it up to date over the coming years.Comment: 54 pages, 26 figures, Accepted for publication in Astrophysics &
Space Scienc
Economic analysis of an agrosilvipastoral system for a mountainous area in Zona da Mata Mineira, Brazil
Anisotropic flow of charged hadrons, pions and (anti-)protons measured at high transverse momentum in Pb-Pb collisions at TeV
The elliptic, , triangular, , and quadrangular, , azimuthal
anisotropic flow coefficients are measured for unidentified charged particles,
pions and (anti-)protons in Pb-Pb collisions at TeV
with the ALICE detector at the Large Hadron Collider. Results obtained with the
event plane and four-particle cumulant methods are reported for the
pseudo-rapidity range at different collision centralities and as a
function of transverse momentum, , out to GeV/.
The observed non-zero elliptic and triangular flow depends only weakly on
transverse momentum for GeV/. The small dependence
of the difference between elliptic flow results obtained from the event plane
and four-particle cumulant methods suggests a common origin of flow
fluctuations up to GeV/. The magnitude of the (anti-)proton
elliptic and triangular flow is larger than that of pions out to at least
GeV/ indicating that the particle type dependence persists out
to high .Comment: 16 pages, 5 captioned figures, authors from page 11, published
version, figures at http://aliceinfo.cern.ch/ArtSubmission/node/186
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