The gelatinization and retrogradation properties of wheat starch (WS) with the addition of the combination of stearic acid and sodium alginate (C-SA-AG) were investigated in this study. The results ...of differential scanning calorimetry (DSC) showed that C-SA-AG significantly increased the gelatinization onset temperature of WS by 2.6–3.4 °C, whereas decreased the gelatinization enthalpy of WS by 5.7–6.7 J/g. This suggested that C-SA-AG could obviously delay the gelatinization process of WS. The gel firmness, retrogradation enthalpy, the ratio of intensity at the band of 1047 cm−1 to 1022 cm−1 (R1047/1022), and the relative crystallinity (RC) of WS were significantly decreased with the addition of C-SA-AG by 322–346 g, 0.51–1.78 J/g, 0.06–0.12, and 7.12–9.05% after stored for 7 days at 4 °C, respectively. However, the loss factor (tanδt/tanδ0) was increased by 0.49–0.54 after sweeping for 120 min. This suggested that C-SA-AG could effectively retard the retrogradation of WS. During storage, the retrograded WS containing SA showed V-type crystal structure, which lost the A-type crystal structure of native WS.
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•Combination of SA and AG (C-SA-AG) was used to investigate the properties of WS.•C-SA-AG delayed the gelatinization process of WS.•C-SA-AG could effectively retard the retrogradation of WS.•The RC value of WS was decreased with the C-SA-AG.•Crystalline structure of retrograded WS with C-SA-AG changed from A-type to V-type.
USE OF COMPLEXING AGENTS FOR INCREASED TARGETED PRODUCTION OF CYCLODEXTRINS BY COMMERCIAL ENZYME TORUZYME®. Cyclodextrins (CDs) are cyclic oligosaccharides, products of the intramolecular ...transglycosylation reaction promoted by the enzyme cyclomaltodextrin glucanotransferase (CGTase). The most commonly produced CDs are a-CD, b-CD and g-CD, composed of 6, 7 and 8 glucose molecules, respectively. They form non-covalent inclusion complexes with several molecules, increasing their stability and/or solubility. Due to the importance of CDs and the various industrial applications, this work aimed to use the commercial enzyme Toruzyme® to obtain CDs and direct its production to a-CD or b-CD through the use of ethanol and complexing agents in the reaction medium. The reaction medium added with ethanol and cyclohexanecarboxylic acid directed the production to b-CD, reaching 47.09 mg mL-1 of this molecule. The production medium containing ethanol and stearic acid proved to be more advantageous for the production of a-CD and, after 48 h of reaction, the production of a-CD reached 19.57 mg mL-1, a value six times greater than that of amount of b-CD produced. With this study it was possible to prove that with the use of ethanol and complexing agents in the reaction medium it is possible to direct the production of a certain CD and, thus, make different CGTases economically viable for industrial use.
The superhydrophobic layers were prepared simultaneously on the copper-based cathode and anode surface by one-step electrodeposition. During the electrodeposition process, the reactions on the ...surfaces of copper-based cathode/anode electrodes were different, therefore different superhydrophobic layers were formed on cathode/anode surface. The wettability, surface morphology and chemical composition were characterized by contact angle measurement, scanning electron microscopy, fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy. The formation mechanism and anti-icing performance of the superhydrophobic layers were explored. Superhydrophobic CuCH3(CH2)16COO2 films with dendritic micro/nano hierarchical structure and superhydrophobic Cu2O-stearic acid films with cubic crystal-like micro/nano hierarchical structure were prepared on the surface of the anode and cathodic copper electrode respectively. When the deposition voltage was 4 V and the deposition time was 30 min, the static contact angle reached a maximum of 151.3° on the anode surface and 154° on the cathode surface. Both superhydrophobic films can effectively slow down the icing time. The icing delay effect of the superhydrophobic film on the cathode copper is better, and the delay time was up to 221 s, compared to the original copper surface.
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•The superhydrophobic layers were prepared simultaneously on the copper-based cathode and anode surface by a one-step electrodeposition method.•Superhydrophobic Cu2O-stearic acid films with cubic crystal-like micro/nano hierarchical structure were prepared on the surface of the cathodic copper electrode.•Superhydrophobic CuCH3(CH2)16COO2 films with dendritic micro/nano hierarchical structure were prepared on the surface of the anode copper electrode.•Both superhydrophobic films can effectively slow down the icing time of the copper-based surface.
The present investigation aims to develop a potential composite phase change material (PCM) with leak-resistive and high thermal conductivity. Sugar beet pulp (CSBP) as an industrial waste was ...carbonized to produce a porous framework and used for solving leakage issue and boosting thermal conductivity of capric-stearic acid eutectic mixture (CSEM) used as PCM. FTIR and XRD results proved that the integration of CSEM and CSBP was carried out physically. The SEM analysis demonstrated that the CSEM was well uniformly impregnated within the pores of CSBP scaffold. DSC analysis revealed that the CSBP/CSEM (70 wt%) composite showed melting enthalpy and temperature as 117 J/g and 24 °C. The TGA measurements demonstrated that the produced composite was thermally stable. The incorporation of CSEM with CSBP leaded to a 79% increase in its thermal conductivity and this improvement was proved by comparing heating-cooling periods of CSEM and the composite PCM. The latent heat of the composite PCM was reduced less than 3% as its melting temperature was almost constant after 1000 thermal cycles. All findings of this work disclosed that the developed CSBP/CSEM as cost-effective and environmentally friendly composite PCM can be handled potential TES material for temperature controlling of buildings.
•CSBP was evaluated for avoiding leakage problem and boosting thermal conductivity of CSEM used as PCM.•High amount (70%) of molten CSEM was successfully impregnated into pores of CSBP.•CSBP/CSEM (70 wt%) showed melting enthalpy and temperature as 117 J/g and 24 °C.•The integration of CSEM with CSBP leaded to a significantly increase in its thermal conductivity as 79%.•CSBP/CSEM can be evaluated as cost-effective and eco-friendly friendly composite PCM for temperature controlling in buildings.
Superhydrophobic surface was fabricated by transferring dendrite-like structures to aluminum substrate, exhibiting anti-corrosion performance under the synergistic action of epoxy coating and air ...cushion.
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The superhydrophobic surface was successful fabricated through spin-coating epoxy resin firstly and transferring the dendrite-like structures to aluminum substrate coated with epoxy resin. The combination of organic coating and superhydrophobic surface with dendritic micro-nano structures prevent the permeation of corrosive ions more effectively. The results indicated the fabricated superhydrophobic surfaces possessed a WCA and WSA of nearly 154° and 0°, exhibiting good superhydrophobicity. Besides, the superhydrophobic surface displayed an excellent repellency to acidic or alkaline droplets. The self-cleaning performance of the superhydrophobic surface against fine sand and chalk dust was also proved. Moreover, the anti-corrosion property of superhydrophobic surface has greatly improved due to the dual function of epoxy resin and the air pockets trapped in superhydrophobic surface. This eco-friendly and facile approach provides a novel strategy to prevent metal from corrosion, which will promote the application of superhydrophobic surface in metal protection field.
We determined the effects of altering the ratio of palmitic (C16:0) and stearic (C18:0) acids in supplemental fatty acid (FA) blends on production responses of mid-lactation dairy cows. Twenty-four ...multiparous Holstein cows (mean ± standard deviation; 47.1 ± 5.8 kg of milk yield, 109 ± 23 DIM) were randomly assigned to treatment sequences in a replicated 4 × 4 Latin square design with 21-d periods. Treatments were a control diet not supplemented with FA (CON), and 3 diets incorporating 1.5% of dry matter (DM) FA supplement blends containing 30% C16:0 + 50% C18:0, 50% C16:0 + 30% C18:0, and 80% C16:0 + 10% C18:0. Additionally, the FA blends were balanced to contain 10% of oleic acid (cis-9 C18:1). The FA blends replaced soyhulls in the CON diet. Diets were formulated to contain (% of DM) 31.0% neutral detergent fiber, 27.0% starch, and 16.9% crude protein. The statistical model included the random effect of cow within square and the fixed effects of period, treatment, and their interaction. Preplanned contrasts included CON versus overall effect of FA supplementation and the linear and quadratic effects of increasing C16:0 in FA blends. Overall FA treatment had no effect on dry matter intake (DMI), but increasing C16:0 linearly increased DMI. Compared with CON, overall FA treatment increased yields of milk, 3.5% of fat-corrected milk, energy-corrected milk, and milk fat but did not affect milk protein yield. Increasing C16:0 linearly increased milk fat yield and tended to linearly increase the yields of 3.5% of fat-corrected milk and energy-corrected milk. Fatty acid supplementation decreased the yield of de novo milk FA but increased yields of mixed and preformed milk FA compared with CON. Increasing C16:0 in FA treatments did not affect the yield of de novo milk FA, linearly increased the yield of mixed, and decreased the yield of preformed milk FA. In summary, feeding FA supplements containing C16:0 and C18:0 increased milk production responses with no effect on DMI compared with a control diet. Mid-lactation cows producing ∼40 to 50 kg/d milk yield responded best to increasing supplemental C16:0 in FA supplements, demonstrating that FA supplements higher in C16:0 and limited in C18:0 improves production responses.
•Novel stearic acid/expanded graphite-graphene films PCMs for photothermal storage.•Enhanced thermal conductivity up to 27.1 W/(m·K) using only 12.6 wt% filler.•Ultra-high thermal conductivity of ...105.6 W/(m·K) was attained with only 26.4 wt% filler.•High thermal conductivity PCM significantly enhances photothermal storage efficiency.
Phase change materials (PCMs) have garnered significant attention as a prospective solution for photothermal energy storage, attributed to their notable energy density. Nonetheless, the constrained thermal conductivity of PCMs leads to delayed heat storage from the photothermal conversion surface, causing a build-up of heat at the surface and significant heat dissipation into the surroundings. Additionally, the risk of PCM leakage poses a significant challenge to the long-term reliability of these systems. To address these issues, we propose a novel approach that synergistically utilizes expanded graphite-encapsulated phase change material (stearic acid) in conjunction with highly directional graphene films, co-assembled through hot pressing, to create laminated phase change composites with superior thermal conductivity. This innovative approach significantly enhances the thermal conductivity of the phase change composite, achieving an impressive 27.1 W/(m·K) with only 12.6 wt% of thermal filler. Remarkably, an exceptionally high thermal conductivity of 105.6 W/(m·K) can be attained with less than 26.4 wt% thermal filler. Moreover, we have introduced an advanced high-photothermal conversion layer that synergizes with our directionally conductive phase change composite. This strategic combination culminates in the creation of a highly efficient integrated photothermal storage device, markedly boosting the overall efficiency of photothermal energy integration. This innovative design offers a practical and scalable solution for high-capacity and high-intensity solar thermal energy storage.
New strategies are being investigated to ameliorate the efficacy and reduce the toxicity of the drugs currently used in colorectal cancer (CRC), one of the most common malignancies in the Western ...world. Data have been accumulated demonstrating that the antineoplastic therapies with either conventional or single-targeted drugs could take advantage from a combined treatment with omega-3 polyunsaturated fatty acids (omega-3 PUFA). These nutrients, shown to be safe at the dosage generally used in human trials, are able to modulate molecules involved in colon cancer cell growth and survival. They have also the potential to act against inflammation, which plays a critical role in CRC development, and to increase the anti-cancer immune response. In the present study, omega-3 PUFA were encapsulated in solid lipid nanoparticles (SLN) having a lipid matrix containing resveratrol esterified to stearic acid. Our aim was to increase the efficiency of the incorporation of these fatty acids into the cells and prevent their peroxidation and degradation. The Resveratrol-based SLN were characterized and investigated for their antioxidant activity. It was observed that the encapsulation of omega-3 PUFA into the SLN enhanced significantly their incorporation in human HT-29 CRC cells in vitro, and their growth inhibitory effects in these cancer cells, mainly by reducing cell proliferation.
It has been demonstrated that dietary high fat diet negatively affects the pubertal mammary gland development. The aim of the present study was to investigate the effects of stearic acid (SA), an ...18-carbon chain saturated fatty acid, on mammary gland development in pubertal mice and to explore the underlying mechanism. Our results demonstrated that dietary supplementation of 2% SA suppressed mammary duct development, with significant reduction of terminal end bud (TEB) number and ductal branch. In accord, the expression of proliferative marker Cyclin D1 was markedly decreased by dietary SA. Furthermore, dietary SA led to increase of G protein-coupled receptor 120 (GPR120) expression and inhibition of PI3K/Akt signaling pathway in mammary gland of pubertal mice. In good agreement with the in vivo findings, the in vitro results showed that 40 μM SA significantly suppressed proliferation of mouse mammary epithelial cell HC11 by regulating mRNA and/or protein expression of proliferative markers such as Cyclin D1/3, p21, and PCNA. Meanwhile, SA activated GPR120 and inhibited PI3K/Akt signaling pathway in a GPR120-dependent manner. In addition, SA-induced inhibition of PI3K/Akt signaling pathway, suppression of HC11 proliferation, and alteration of proliferative markers expression were abolished by knockdown of GPR120 with siRNA. Collectively, these findings showed that SA suppressed mammary gland development of pubertal mice, which was coincident with the SA-inhibited HC11 proliferation, and was associated with inhibition of PI3K/Akt signaling pathway through activation of GPR120. These data provided new insights into the regulation of mammary gland development by dietary fatty acids.
•Dietary supplementation of 2% SA suppressed mammary duct growth in pubertal mice.•SA inhibited HC11 proliferation by regulating expression of proliferative markers.•SA enhanced GPR120 and inhibited PI3K/Akt in mice mammary gland and HC11 cells.•Knockdown of GPR120 eliminated SA-suppressed PI3K/Akt and HC11 proliferation.
•The effects of different solid lipids with different length chains on echium oil encapsulates were investigated.•Lauric acid (C12), palmitic acid (C16), and stearic acid (C18) were used as solid ...lipids.•Adding solid lipid clearly decreased the droplet size and increased the physical stabilities.•Partially or fully solidified of droplets by adding solid lipids increased the echium oil oxidation stability.•Rheology data showed a crossover shift to lower strains in the G′-G″ curve of the emulsions incorporating lauric acid.
Implementing ω-3 polyunsaturated fatty acids (ω-3 PUFA), naturally found in echium oil (EO), can highly improve the nutritional value of fortified foods. However, PUFA is prone to oxidation. In this study, the role of nanostructured lipid carriers incorporated into whey protein isolate (WPI)-stabilized EO droplets in oil-in-water emulsions was analyzed. Lipid carriers such as lauric (LA), palmitic (PA), and stearic (SA) acids were used. The results reveal that lipid carriers, especially LA, improve the physical stability of these droplets by decreasing their particle size by decreasing the number of surface pores; shown by SEM images and XRD data. Rheological data further show that the emulsions incorporated with LA had higher viscosity and there was also a crossover shift to lower strains in the G′-G″ curve of the emulsions incorporating LA. TBARS assay indicated that LA was more effective in protecting EO against oxidation than both palmitic and stearic acids.
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