Properties and functions of stabilizing agents in food emulsions

No effective therapeutics to treat neurodegenerative diseases exist, despite significant attempts to find drugs that can reduce or rescue the debilitating symptoms of tauopathies such as Alzheimer’s disease, Parkinson’s disease, frontotemporal dementia, amyotrophic lateral sclerosis, or Pick’s disease. A number of in vitro and in vivo models exist for studying neurodegenerative diseases, including cell models employing induced-pluripotent stem cells, cerebral organoids, and animal models of disease. Recent research has focused on microtubulestabilizing agents, either natural products or synthetic compounds that can prevent the axonal destruction caused by tau protein pathologies. Although promising results have come from animal model studies using brainpenetrant natural product microtubule-stabilizing agents, such as paclitaxel analogs that can access the brain, epothilones B and D, and other synthetic compounds such as davunetide or the triazolopyrimidines, early clinical trials in humans have been disappointing. This review aims to summarize the research that has been carried out in this area and discuss the potential for the future development of an effective microtubule stabilizing drug to treat neurodegenerative disease.

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Efficacy Assessment of Biosynthesized Copper Oxide Nanoparticles (CuO-NPs) on Stored Grain Insects and Their Impacts on Morphological and Physiological Traits of Wheat (Triticum aestivum L.) Plant

Biology ◽

10.3390/biology10030233 ◽

2021 ◽

Vol 10 (3) ◽

pp. 233

Author(s):

Ali A. Badawy ◽

Nilly A. H. Abdelfattah ◽

Salem S. Salem ◽

Mohamed F. Awad ◽

Amr Fouda

Keyword(s):

Block Design ◽

Dry Weight ◽

Triticum Aestivum L ◽

Copper Oxide Nanoparticles ◽

Rhyzopertha Dominica ◽

Stored Grain ◽

Stabilizing Agents ◽

Cuo Nps ◽

Vis Spectroscopy ◽

Ft Ir

Herein, CuO-NPs were fabricated by harnessing metabolites of Aspergillus niger strain (G3-1) and characterized using UV–vis spectroscopy, XRD, TEM, SEM-EDX, FT-IR, and XPS. Spherical, crystallographic CuO-NPs were synthesized in sizes ranging from 14.0 to 47.4 nm, as indicated by TEM and XRD. EDX and XPS confirmed the presence of Cu and O with weight percentages of 62.96% and 22.93%, respectively, at varied bending energies. FT-IR spectra identified functional groups of metabolites that could act as reducing, capping, and stabilizing agents to the CuO-NPs. The insecticidal activity of CuO-NPs against wheat grain insects Sitophilus granarius and Rhyzopertha dominica was dose- and time-dependent. The mortality percentages due to NP treatment were 55–94.4% (S. granarius) and 70–90% (R. dominica). A botanical experiment was done in a randomized block design. Low CuO-NP concentration (50 ppm) caused significant increases in growth characteristics (shoot and root length, fresh and dry weight of shoot and root, and leaves number), photosynthetic pigments (total chlorophylls and carotenoids), and antioxidant enzymes of wheat plants. There was no significant change in carbohydrate or protein content. The use of CuO-NPs is a promising tool to control grain insects and enhance wheat growth performance.

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Synthesis of green and pure copper oxide nanoparticles using two plant resources via solid-state route and their phytotoxicity assessment

RSC Advances ◽

10.1039/d0ra09924d ◽

2021 ◽

Vol 11 (6) ◽

pp. 3346-3353

Author(s):

Iman Khaldari ◽

Mohammad Reza Naghavi ◽

Elaheh Motamedi

Keyword(s):

Solid State ◽

Copper Oxide ◽

Pure Copper ◽

Copper Oxide Nanoparticles ◽

Oxide Nanoparticles ◽

Plant Resources ◽

Stabilizing Agents ◽

Biological Resources ◽

Solid State Route ◽

Conventional Methods

Among the conventional methods in synthesizing nanoparticles, the methods that use biological resources, as reducing and stabilizing agents, can be considered eco-friendly methods.

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Preparation of Fe3O4-Ag Nanocomposites with Silver Petals for SERS Application

Nanomaterials ◽

10.3390/nano11051288 ◽

2021 ◽

Vol 11 (5) ◽

pp. 1288

Author(s):

Thi Thuy Nguyen ◽

Fayna Mammeri ◽

Souad Ammar ◽

Thi Bich Ngoc Nguyen ◽

Trong Nghia Nguyen ◽

...

Keyword(s):

Self Assembly ◽

Hot Spots ◽

Surface Enhanced Raman Spectroscopy ◽

Electrical Field ◽

Stabilizing Agents ◽

Surface Enhanced ◽

Surface Enhanced Raman ◽

Sers Sensing ◽

Applied Electrical Field ◽

Positively Charged

The formation of silver nanopetal-Fe3O4 poly-nanocrystals assemblies and the use of the resulting hetero-nanostructures as active substrates for Surface Enhanced Raman Spectroscopy (SERS) application are here reported. In practice, about 180 nm sized polyol-made Fe3O4 spheres, constituted by 10 nm sized crystals, were functionalized by (3-aminopropyl)triethoxysilane (APTES) to become positively charged, which can then electrostatically interact with negatively charged silver seeds. Silver petals were formed by seed-mediated growth in presence of Ag+ cations and self-assembly, using L-ascorbic acid (L-AA) and polyvinyl pyrrolidone (PVP) as mid-reducing and stabilizing agents, respectively. The resulting plasmonic structure provides a rough surface with plenty of hot spots able to locally enhance significantly any applied electrical field. Additionally, they exhibited a high enough saturation magnetization with Ms = 9.7 emu g−1 to be reversibly collected by an external magnetic field, which shortened the detection time. The plasmonic property makes the engineered Fe3O4-Ag architectures particularly valuable for magnetically assisted ultra-sensitive SERS sensing. This was unambiguously established through the successful detection, in water, of traces, (down to 10−10 M) of Rhodamine 6G (R6G), at room temperature.

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Quantitative and Predictive Modelling of Lipid Oxidation in Mayonnaise

Antioxidants ◽

10.3390/antiox10020287 ◽

2021 ◽

Vol 10 (2) ◽

pp. 287

Author(s):

Donny W. H. Merkx ◽

Andries Swager ◽

Ewoud J. J. van Velzen ◽

John P. M. van Duynhoven ◽

Marie Hennebelle

Keyword(s):

Lipid Oxidation ◽

Oxidative Stability ◽

Shelf Life ◽

Onset Time ◽

Predictive Modelling ◽

Oxidation Products ◽

Food Emulsions ◽

Hydroperoxide Formation ◽

Life Tests ◽

Volatile Aldehydes

Food emulsions with high amounts of unsaturated fats, such as mayonnaise, are prone to lipid oxidation. In the food industry, typically accelerated shelf life tests are applied to assess the oxidative stability of different formulations. Here, the appearance of aldehydes at the so-called onset time, typically weeks, is considered a measure for oxidative stability of food emulsions, such as mayonnaise. To enable earlier assessment of compromised shelf-life, a predictive model for volatile off-flavor generation is developed. The model is based on the formation kinetics of hydroperoxides, which are early oxidation products and precursors of volatile aldehydes, responsible for off-flavor. Under accelerated shelf-life conditions (50 °C), hydroperoxide (LOOH) concentration over time shows a sigmoidal curvature followed by an acceleration phase that occurs at a LOOH-concentration between 38–50 mmol/kg, here interpreted as a critical LOOH concentration (CCLOOH). We hypothesize that the time at which CCLOOH was reached is related to the onset of aldehyde generation and that the characterization of the LOOH-generation curvature could be based on reaction kinetics in the first days. These hypotheses are tested using semi-empirical models to describe the autocatalytic character of hydroperoxide formation in combination with the CCLOOH. The Foubert function is selected as best describing the LOOH-curvature and is hence used to accurately predict onset of aldehyde generation, in most cases within several days of shelf-life. Furthermore, we find that the defining parameters of this model could be used to recognize antioxidant mechanisms at play.

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Enhanced sunlight photocatalytic activity and biosafety of marine-driven synthesized cerium oxide nanoparticles

Scientific Reports ◽

10.1038/s41598-021-94327-w ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Somayeh Safat ◽

Foad Buazar ◽

Salim Albukhaty ◽

Soheila Matroodi

Keyword(s):

Photocatalytic Activity ◽

Band Gap ◽

Color Change ◽

Removal Rate ◽

Average Crystallite Size ◽

Face Centered Cubic ◽

One Pot ◽

Stabilizing Agents ◽

Face Centered ◽

Living Organisms

AbstractThis contribution presents the biosynthesis, physiochemical properties, toxicity and photocatalytic activity of biogenic CeO2 NPs using, for the first time, marine oyster extract as an effective and rich source of bioreducing and capping/stabilizing agents in a one-pot recipe. CeO2 NPs formation was initially confirmed through the color change from light green to pale yellow and subsequently, their corresponding absorption peak was spectroscopically determined at 310 nm with an optical band-gap of 4.67 eV using the DR-UV technique. Further, XRD and Raman analyses indicated that nanoceria possessed face-centered cubic arrangements without any impurities, having an average crystallite size of 10 nm. TEM and SEM results revealed that biogenic CeO2 NPs was approximately spherical in shape with a median particle size of 15 ± 1 nm. The presence of various bioorganic substances on the surface of nanoparticles was deduced by FTIR and TGA results. It is found that marine-based nanoceria shows no cytotoxic effect on the normal cell, thus indicating their enhanced biocompatibility and biosafety to living organisms. Environmentally, due to energy band gap, visible light-activated CeO2 nanocatalyst revealed superior photocatalytic performance on degradation of methylene blue pollutant with removal rate of 99%. Owing to the simplicity, cost-effectiveness, and environmentally friendly nature, this novel marine biosynthetic route paves the way for prospective applications of nanoparticles in various areas.

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Green approach in gold, silver and selenium nanoparticles using coffee bean extract

Open Agriculture ◽

10.1515/opag-2020-0074 ◽

2020 ◽

Vol 5 (1) ◽

pp. 761-767

Author(s):

Reiyhaneh Abbasian ◽

Hoda Jafarizadeh-Malmiri

Keyword(s):

Spherical Shape ◽

Coffee Bean ◽

Hydrothermal Conditions ◽

Ag Nps ◽

Au Nps ◽

Stabilizing Agents ◽

E Coli ◽

Green Approach ◽

Gold Silver ◽

Ft Ir

AbstractGreen fabrication of metal nanoparticles (NPs), using natural reducing and stabilizing agents existed in plants and their derivatives, due to their unique properties, has gained more attention. The present study focuses on the synthesis of gold (Au), silver (Ag) and selenium (Se) NPs using coffee bean extract under hydrothermal conditions (1.5 atm and 121°C, for 15 min). Coffee bean extract obtained in 2 h processing using Clevenger apparatus and Fourier transform-infrared (FT-IR) spectroscopy indicated five highlighted peaks, namely, hydroxyl, amide, aromatic, alkane and ring groups. Dynamic light scattering analysis revealed that among three different NPs formed, fabricated Ag NPs had small particle size (153 nm) and high zeta potential value (16.8 mV). However, synthesized Au NPs had minimum polydispersity index (0.312). Results also indicated that fabricated Au, Se and Ag NPs had low antioxidant activity with values of 9.1, 8.9 and 8.7%, respectively. Morphological and antibacterial activity assessments, demonstrated that synthesized Ag, Au and Se NPs had spherical shape and high bactericidal activity against E. coli and S. aurous. Obtained results indicated that the synthesized NPs, can be utilized in various areas.

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