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991.
Hammad Ullah Yaseen Hussain Cristina Santarcangelo Alessandra Baldi Alessandro Di Minno Haroon Khan Jianbo Xiao Maria Daglia 《Molecules (Basel, Switzerland)》2022,27(6)
Food spoilage makes foods undesirable and unacceptable for human use. The preservation of food is essential for human survival, and different techniques were initially used to limit the growth of spoiling microbes, e.g., drying, heating, salting, or fermentation. Water activity, temperature, redox potential, preservatives, and competitive microorganisms are the most important approaches used in the preservation of food products. Preservative agents are generally classified into antimicrobial, antioxidant, and anti-browning agents. On the other hand, artificial preservatives (sorbate, sulfite, or nitrite) may cause serious health hazards such as hypersensitivity, asthma, neurological damage, hyperactivity, and cancer. Thus, consumers prefer natural food preservatives to synthetic ones, as they are considered safer. Polyphenols have potential uses as biopreservatives in the food industry, because their antimicrobial and antioxidant activities can increase the storage life of food products. The antioxidant capacity of polyphenols is mainly due to the inhibition of free radical formation. Moreover, the antimicrobial activity of plants and herbs is mainly attributed to the presence of phenolic compounds. Thus, incorporation of botanical extracts rich in polyphenols in perishable foods can be considered since no pure polyphenolic compounds are authorized as food preservatives. However, individual polyphenols can be screened in this regard. In conclusion, this review highlights the use of phenolic compounds or botanical extracts rich in polyphenols as preservative agents with special reference to meat and dairy products. 相似文献
992.
Anca Corina Frca Sonia Ancua Socaci Maria Simona Chi Francisc Vasile Dulf Paula Podea Maria Tofan 《Molecules (Basel, Switzerland)》2022,27(6)
Apple industrial by-products are a promising source of bioactive compounds with direct implications on human health. The main goal of the present work was to characterize the Jonathan and Golden Delicious by-products from their fatty acid, amino acid, and volatile aroma compounds’ point of view. GC-MS (gas chromatography-mass spectrometry) and ITEX/GC-MS methods were used for the by-products characterization. Linoleic and oleic were the main fatty acids identified in all samples, while palmitic and stearic acid were the representant of saturated ones. With respect to amino acids, from the essential group, isoleucine was the majority compound identified in JS (Jonathan skin) and GS (Golden skin) samples, lysine was the representant of JP (Jonathan pomace), and valine was mainly identified in GP (Golden pomace). A total number of 47 aroma volatile compounds were quantified in all samples, from which the esters groups ranged from 41.55–53.29%, aldehydes 29.75–43.99%, alcohols from 4.15 to 6.37%, ketones 4.14–5.72%, and the terpenes and terpenoids group reached values between 2.27% and 4.61%. Moreover, the by-products were valorized in biscuits manufacturing, highlighting their importance in enhancing the volatile aroma compounds, color, and sensorial analysis of the final baked goods. 相似文献
993.
994.
Li-Bo Huang Maria Di Vincenzo Dr. Yuhao Li Dr. Mihail Barboiu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(7):2224-2239
Natural Aquaporin (AQP) channels are efficient water translocating proteins, rejecting ions. Inspired by this masterpiece of nature, Artificial Water Channels (AWCs) with controlled functional structures, can be potentially used to mimic the AQPs to a certain extent, offering flexible avenues toward biomimetic membranes for water purification. The objective of this paper is to trace the historical development and significant advancements of current reported AWCs. Meanwhile, we attempt to reveal important structural insights and supramolecular self-assembly principles governing the selective water transport mechanisms, toward innovative AWC-based biomimetic membranes for desalination. 相似文献
995.
Marco Angelucci Pierluigi Gargiani Carlo Mariani Maria Grazia Betti 《Journal of nanoparticle research》2011,13(11):5967-5973
Iron-Phthalocyanine molecules deposited on the Cu(119) vicinal surface form molecular chains along the vicinal surface steps,
as deduced by the low-energy electron diffraction (LEED) reconstruction pattern. The work-function lowers at the FePc single-layer
completion, due to the formation of an interface dipole. Further FePc deposition induces a different growth morphology, as
suggested by the slope discontinuity in the work function variation. Upon depositing potassium onto the FePc thin-film prepared
on Cu(119), the K-injected electrons fill up the Fe-d-associated and ligand-π-related orbitals, as observed by means of high-resolution
ultraviolet photoelectron spectroscopy. 相似文献
996.
Vivian?Regina?Trist?o Fernando?Felippe?de?Carvalho Cinthia?Zanini?Gomes Adriana?Regina?Miranda Cíntia?C.?Vequi-Suplicy Maria?Teresa?Lamy Nestor?Schor Maria?Helena?Bellini 《Journal of fluorescence》2010,20(3):665-669
The progression to end-stage renal failure is independent of the initial pathogenic mechanism. Metabolic acidosis is a common
consequence of chronic renal failure that results from inadequate ammonium excretion and decreased tubular bicarbonate reabsorption.
Protoporphyrin IX (PpIX) is the immediate metabolic precursor of the heme molecule. The purpose of this study was to evaluate
the levels of erythrocytes protoporphyrin IX at an animal model during progressive renal disease. A total of 36 eight-week-old
male Wistar rats were divided into six groups: Normal, 4 and 8 weeks after 5/6 nephrectomy (NX). Renal function was evaluated
by creatinine clearance and plasma creatinine levels. The autofluorescence of erythrocytes porphyrin of healthy and NX rats
was analyzed using fluorescence spectroscopy. Emission spectra were obtained by exciting the samples at 405 nm. Significant
differences between normal and NX rats autofluorescence shape occurred in the 600–700 nm spectral region. A correlation was
observed between emission band intensity at 635 nm and progression of renal disease. 相似文献
997.
M. C. Fuss A. Mu?oz J. C. Oller F. Blanco P. Lim?o-Vieira A. Williart C. Huerga M. Téllez G. García 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2010,60(1):203-208
In this study, an electron-tracking Monte Carlo algorithm developed by us is combined with established photon transport models
in order to simulate all primary and secondary particle interactions in water for incident photon radiation. As input parameters
for secondary electron interactions, electron scattering cross sections by water molecules and experimental energy loss
spectra are used. With this simulation, the resulting energy deposition can be modelled at the molecular level, yielding detailed
information about localization and type of single collision events. The experimental emission spectrum of I-125 seeds, as
used for radiotherapy of different tumours, was used for studying the energy deposition in water when irradiating with this
radionuclide. 相似文献
998.
999.
Maria Catarina Coutinho Varela da Silva João Luís Maia Figueirinhas 《Liquid crystals》2016,43(1):124-130
A number of polymer dispersed liquid crystal (PDLC) films based on dimethacrylate monomers were synthesised by polymer-induced phase separation (PIPS) using polyethylene glycol p-(1,1,3,3-tetramethylbutyl)-phenyl ether (TX-100) as an additive up to total solution weight of 10% aiming to modify the initial anchorage force of the liquid crystal (LC) molecules to the polymeric matrix. The effects of the addition of this additive to the PDLC films were studied resorting to electro-optical studies. Using a fitting model, several parameters were correlated such as the permanent memory effect (PME), the voltage required to achieve 90% of maximum transmittance (E90), the average elastic constant (K) and the rotational viscosity of the director (γ). The use of TX-100 results on an increase on the PME and γ, and decrease on the E90 and K. 相似文献
1000.
Christina C. Roggatz Mercedes González-Wangüemert Hugo Pereira Maria João Rodrigues Manuela Moreira da Silva Luísa Barreira 《Natural product research》2016,30(18):2034-2040
This work reports for the first time the nutritional profile and antioxidant potential of the edible sea cucumber Holothuria arguinensis from the North-eastern Atlantic. H. arguinensis has high levels of protein, with the amino acids profile dominated by alanine, glycine and proline and low lysine/arginine ratios. Its carbohydrate and energetic contents are also low as well as the total lipid levels, although its lipid profile is rich in polyunsaturated fatty acids (PUFA), especially arachidonic, eicosapentaenoic and docosahexaenoic acids. In addition, H. arguinensis has high levels of calcium. The water and ethanol extracts show ability to scavenge free radicals and to chelate copper and iron ions. Our results indicate that H. arguinensis has a balanced nutritional quality suitable for human consumption. In addition, it contains compounds with antioxidant potential; thus its intake can contribute for a healthy and well-balanced diet. 相似文献