Laccases (benzenediol:oxygen oxidoreductases, EC 1.10.3.2) catalyze the oxidation of a wide variety of organic and inorganic substrates, typically p-diphenols with a concomitant reduction of oxygen ...(O2) to water. Several molecules naturally occurring in foods and beverages (e.g., phenols, carbohydrates, unsatured fatty acids and thiol-containing proteins) can be modified by laccases. Hence, the interaction between laccase and these molecules can and has been widely explored by the food industry for various technological purposes.
The present work aims at providing a critical review on the current uses of laccases in food processing, at discussing the main bottlenecks for its popularization, and at presenting future perspectives. Both scientific reports and patents, covering preferably the last five years, were considered.
Several traditional uses of laccases in food processing including baking, beverage, and dairy industries were detailed. Special efforts were developed, however, in analyzing future perspectives. The latter includes the application of laccases in the synthesis of new compounds with functional properties, such as antioxidant and antimicrobial activities. No less attention was devoted to the recent developments in the field of crosslinking of polymers, such as proteins and polysaccharides. Scaling up of the production of the laccase itself and especially of the novel products derived from its applications in the food sector will be essential for cost reduction and, consequently, for market expansion.
•Laccases are eco-friendly biocatalysts useful in food processing.•They catalyze the oxidation of a wide variety of organic and inorganic substrates.•Phenols, carbohydrates, and proteins can be modified by laccases.•Laccases are useful in the synthesis of new antioxidant and antibacterial molecules.•Laccases find many new applications in the food industry.
Diamond nanothreads (DNTs) are fully sp
-bonded one-dimensional carbon nanostructures, synthesized recently through compression of crystalline benzene. They possess outstanding mechanical strength, ...suitable for the development of novel nanostructured reinforced materials. In this article, we use density functional theory calculations to investigate the feasibility and physical properties of functionalized DNTs. We show that the stacking and covalent bonding of benzene derivative molecules (toluene, aniline, phenol and fluorobenzene) may lead to stable configurations analogous to benzene-derived DNTs, with functional groups (-CH
, -NH
, -OH, -F) covalently attached to the surface. The same principle was also applied to pyridine, an aromatic heterocyclic compound, resulting in DNTs containing N heteroatoms within the sp
C-C chain. We show that the mechanical properties remain practically unaltered compared to the original material, and that the electronic properties can be tuned upon functionalization. The presence of polar functional groups on DNT surfaces are expected to affect their compatibility with other materials and solvents, enabling the development of novel processes and technological applications using DNTs.
L-Arginine and chronic exercise reduce oxidative stress. However, it is unclear how they affect cardiomyocytes during cardiovascular disease (CVD) development. The aim of this research was to ...investigate the possible effects of L- arginine supplementation and aerobic training on systemic oxidative stress and their consequences on cardiomyocytes during cardiometabolic disease onset caused by excess fructose. Wistar rats were allocated into four groups: control (C), fructose (F, 10% fructose in water), fructose training (FT; moderate running, 50-70% of the maximal velocity), and fructose arginine (FA; 880 mg/kg/day). Fructose was given for two weeks and fructose plus treatments for the subsequent eight weeks. Body composition, blood glucose, insulin, lipid profile, lipid peroxidation, nitrite, metalloproteinase-2 (MMP-2) activity, left ventricle histological changes, microRNA-126, -195, and -146, eNOS, p-eNOS, and TNF-alpha expressions were analyzed. Higher abdominal fat mass, triacylglycerol level, and insulin level were observed in the F group, and both treatments reversed these alterations. Myocardial vascularization was impaired in fructose-fed groups, except in FT. Cardiomyocyte hypertrophy was observed in all fructose-fed groups. TNF-alpha levels were higher in fructose-fed groups than in the C group, and p-eNOS levels were higher in the FA than in the C and F groups. Lipid peroxidation was higher in the F group than in the FT and C groups. During CVD onset, moderate aerobic exercise reduced lipid peroxidation, and both training and L-arginine prevented metabolic changes caused by excessive fructose. Myocardial vascularization was impaired by fructose, and cardiomyocyte hypertrophy appeared to be influenced by pro-inflammatory and oxidative environments. Key words: Cardiovascular disease; Exercise; Arginine; Fructose; Oxidative stress
The present study reports on the synthesis and investigation of a series of oxyfluoride phosphate glasses having a composition of (50-
x
)P
2
O
5
-50KF-
x
Al
2
O
3
(PKAl), with
x
= 8 mol.%, ...12 mol.%, 16 mol.%, and 20 mol.%, by the melt-quenching method. The introduction of Al
2
O
3
in the composition promotes a stabilizing effect, producing stable glasses in air and water ambient conditions. X-ray diffraction (XRD) showed the amorphous characteristics of the materials. The glasses presented high transparency in the UV-Vis-NIR regions (340–2000 nm). Differential scanning calorimetry (DSC) results showed that PKAl glasses have low glass transition temperature values (398–456°C). Fourier-transform infrared spectroscopy (FTIR) spectra showed structural changes caused by variations in P
2
O
5
-Al
2
O
3
ratios. The density values of PKAl glasses increased with Al
2
O
3
concentration from 2.45 g/cm
3
to 2.50 g/cm
3
. The molar volume decreases from 39.97 cm
3
/mol to 36.81 cm
3
/mol. The prepared new oxyfluoride phosphate glasses can be useful for photonic device applications such as lasers and light-emitting diodes (LEDs).
•Eu2+ valence state was obtained in sodium silicate glasses. Excitation band was observed 100 nm wider than most materials.•The excitation band overlaps perfectly with the solar spectrum emission in ...UV–VIS region, providing conversion of the energy in c-Si cell.•Eu2+Nd3+ co-doped glass presented an excellent match between the Nd3+ emission and the optimal photoconversion energy.
The challenge of modifying the solar spectrum intensifies efforts in the pursuit of enhanced materials and optical systems. In this work, we present novel and efficient near infrared-emitting Eu2+ and Nd3+ co-doped sodium calcium silicate glasses. Optical absorption, excitation spectra, emission decay time, were measured and discussed as a function of Nd2O3 content. Laser power-dependent emission intensity was used to evaluate the transfer mechanism, and an energy level diagram was proposed. For the sample doped with optimized neodymium content, energy transfer efficiency reached 70%. For co-doped samples, the excitation spectrum was broadly intense and perfectly overlapped with the solar spectrum in the NUV region. Therefore, NUV/Visible can be efficiently converted into NIR, precisely where the C-Si response is maximal, through the Eu2+→Nd3+ pathway. This work’s outcomes made the focused materials worthy for solar cell applications, optimizing energy conversion lost by thermalization, into useful energy.
The peach palm (
Kunth) is a palm tree native to the Amazon region, with plantations expanding to the Brazilian Southwest and South regions. This work is a critical review of historical, botanical, ...social, environmental, and nutritional aspects of edible and nonedible parts of the plant. In Brazil, the importance of the cultivation of
to produce palm heart has grown considerably, due to its advantages in relation to other palm species, such as precocity, rusticity and tillering. The last one is especially important, as it makes the exploitation of peach palm hearts, contrary to what happens with other palm tree species, a non-predatory practice. Of special interest are the recent efforts aiming at the valorization of the fruit as a source of carotenoids and starch. Further developments indicate that the
lignocellulosic wastes hold great potential for being upcycled into valuable biotechnological products such as prebiotics, enzymes, cellulose nanofibrils and high fiber flours. Clean technologies are protagonists of the recovery processes, ensuring the closure of the product's life cycle in a "green" way. Future research should focus on expanding and making the recovery processes economically viable, which would be of great importance for stimulating the peach palm production chain.
•TNF-α levels were significantly higher in individuals with HCC.•IL-10 levels were significantly higher in HCV patients with mild fibrosis.•High TNF-α/IL-10 ratio was associated with HCC ...occurrence.•TNF-α/IL-10 ratio may predict severe hepatic disease in HCV infected individuals.
Hepatitis C virus (HCV) is the main cause of chronic liver disease, cirrhosis and hepatocellular carcinoma (HCC) worldwide. The risk for the development of HCC increases with the severity of liver inflammation and fibrosis. The hepatic inflammation caused by HCV involves host regulatory immune response, which is mediated by cytokines with anti-viral role upon the interaction of viral polypeptides with innate and adaptive immunity. Two cytokines; tumor necrosis factor-α (TNF-α) and interleukin-10 (IL-10) play key roles in the regulation of cellular immune response in HCV infection. The aim of the present study was to determine the levels of IL-10 and TNF-α, as well as the ratio of TNF-α and IL-10 serum levels in patients with HCV and HCC caused by HCV (HCC–HCV). The study included 173 patients with chronic HCV. TNF-α and IL-10 serum levels were measured by ELISA (R&D Systems, Inc.). In the present study, 54 patients presented liver mild fibrosis, 68 had severe fibrosis and 51 patients had HCC. After adjustment in the multivariate regression analysis, the following variables remained significantly associated with HCC–HCV occurrence: diabetes (p=0.012 OR 10.44 CI 1.66–65.60), IL-10 lower levels (p<0.0001 OR 0.83 CI 0.78–0.89) and TNF-α higher levels (p<0.0001 OR 1.19 CI 1.11–1.28). Individuals with HCC presented higher TNF-α/IL-10 ratio than those with fibrosis grade F4, F3 or F0+F1+F2 (p=0.0003, p<0.0001, p<0.0001, respectively). Patients with HCC were associated to higher index TNF-α/IL-10 ratio, suggesting that the unbalanced production of these cytokines may represent progression to the liver disease severity in HCV infected patients.
A. Juss (neem) extracts have been used in pharmaceutical applications as antitumor agents, due to their terpenes and phenolic compounds. To obtain extracts from neem leaves with potential ...antiproliferative effect, a sequential process of pressurized liquid extraction was carried out in a fixed bed extractor at 25 °C and 100 bar, using hexane (SH), ethyl acetate (SEA), and ethanol (SE) as solvents. Extractions using only ethanol (EE) was also conducted to compare the characteristics of the fractionated extracts. The results obtained by liquid chromatography-electrospray ionization mass spectrometry suggested a higher concentration of terpenes in the SEA extract in comparison to SH, SE, and EE extracts. Therefore, antiproliferative activity showed that SEA extracts were the most efficient inhibitor to human tumor cells MCF-7, NCI-H460, HeLa, and HepG2. Hepatocellular cells were more resistant to SH, SEA, SE, and EE compared to breast, lung, hepatocellular, and cervical malignant cells. Neem fractioned extracts obtained in the present study seem to be more selective for malignant cells compared to the non-tumor cells.
Foliar uptake of dew is likely an important mechanism of water acquisition for plants from tropical dry environments. However, there is still limited experimental evidence describing the anatomical ...pathways involved in this process and the effects of this water subsidy on the maintenance of gas exchange and leaf lifespan of species from seasonally dry tropical vegetation such as the Brazilian caatinga.
We performed scanning electron, bright‐field and confocal microscopic analyses and used apoplastic tracers to examine the foliar water uptake (FWU) routes in four woody species with different foliar phenology and widely distributed in the caatinga. Leaves of plants subjected to water stress were exposed to dew simulation to evaluate the effects of the FWU on leaf water potentials, gas exchange and leaf lifespan.
All species absorbed water through their leaf cuticles and/or peltate trichomes but FWU capacity differed among species. Leaf wetting by dew increased leaf lifespan duration up to 36 days compared to plants in the drought treatment. A positive effect on leaf gas exchange and new leaf production was only observed in the anisohydric and evergreen species.
We showed that leaf wetting by dew is relevant for the physiology and leaf lifespan of plants from seasonally dry tropical vegetation, especially for evergreen species.
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