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991.
Arun K. Verma V. Rajkumar Ravindra Kumar K. Gururaj Tarun Pal Singh Manoj K. Singh 《European Journal of Lipid Science and Technology》2023,125(10):2300143
This study investigated the effect of supplementing omega fatty acids-rich oil blend, composed of sunflower oil (1.5% and 3.0%), linseed oil (1.5% and 3.0%), and FineXNV1810 (20 g) on the carcass, meat quality, fatty acid profile, and genes (peroxisome proliferator-activated receptor-α, stearoyl-CoA desaturase, acetyl-CoA carboxylase, hydroxy-3-methylglutaryl coenzyme A, and leptin) of Barbari goats. The goat kids (n = 18) were divided into three groups, namely, group A: basal diet; group B: basal diet + oil blend level 1; and group C: basal diet + oil blend level 2, and subjected to the feeding trial for 120 days followed by slaughter and meat quality studies. No treatment effect was recorded in carcass characteristics, pH, water holding capacity, and proximate composition of meat. However, a significant (p < 0.05) treatment effect was observed in cooking loss, lightness, yellowness, and shear force values of meat. There were significant differences (p < 0.05) in linoleic acid, α-linolenic acids, conjugated linoleic acid (CLA), polyunsaturated fatty acids (PUFA), n − 3 and n − 6 PUFA, PUFA/saturated fatty acids and n − 6/n − 3 ratios, and thrombogenic index among groups. An upregulation of the studied genes in the supplemented groups was observed. There were upregulations in the studied genes in the supplemented groups. Practical applications: Goat meat is in great demand the world over, especially in tropical countries, including India, and does not carry any social or religious prohibition. Although goat meat has relatively less fat, consumers express their concern over the presence of undesirable fatty acids. The present study shows that the fatty acid configuration of goat meat can be improved by a dietary supplementation of an oil blend rich in omega fatty acids. The amount of n − 3 PUFA, n − 6 PUFA, and CLA in goat meat was significantly increased due to the dietary oil blend making it healthy for the consumers. Moreover, the dietary oil blend at the studied levels did not significantly affect the growth and meat quality parameters of the goats. Thus, the studied approach can be successfully followed to produce healthier goat meat. 相似文献
992.
Mengfan Zhang Xiaotong Peng Yansheng Huang Kai Li Jing Zhang Pu Xiao Yingshan Zhou 《大分子材料与工程》2023,308(10):2300085
3D printing is an attractive method to accurately construct artificial organs or alternative materials with complicated structures and functional performance. Naturally derived hydrogels have emerged as promising materials for the preparation of biomimetic 3D organization or scaffolds by 3D printing due to their good biocompatibility, high water content, and fascinating 3D network. However, the poor printing properties and weak structural stability of naturally derived hydrogels limit their applications. In this study, photopolymerizable hydrogels are designed based on maleic chitosan (MCS) and thiolated sodium hyaluronate (SHHA). The Michael addition between MCS and SHHA improves the viscosity of the mixed solution. Moreover, it benefits the 3D printing process, followed by photopolymerization (acrylate-thiol step-chain polymerization and acrylate–acrylate chain polymerization) to form a stable covalent network rapidly. The rheological property, swelling behaviors, microstructure, and in vitro degradation are tuned by adjusting the molar ratio of the thiol group and acrylate group. In addition, MCS/SHHA hydrogel scaffolds with good accuracy and enhanced structural stability are prepared using extrusion-based 3D printing and photopolymerization technology. The hydrogels display excellent cytocompatibility and can support adherence of L929 cells, which can be used as prospective materials for tissue engineering applications. 相似文献
993.
Achim Schmidt-Rodenkirchen Prof. Dr. Thorsten Gerdes Dr. Klaus Hintzer Dr. Michael Schlipf 《化学,工程师,技术》2023,95(8):1215-1227
In fluoropolymers, a large portion or even all of the hydrogen atoms in a polymer chain are replaced by fluorine, which results in a number of special properties such as high chemical and temperature resistance. As a result of this combination of properties, these high-performance polymers are not replaceable, or only with difficulty, for some applications. The recycling of polymers and the associated closing of material loops is an essential development task for the entire polymer industry. Materials such as fluoropolymers have a special position due to their chemical composition and their low market volume, as they cannot be recycled together with other bulk polymers at the end of their life cycle. This paper discusses different processes in terms of their technical maturity and suitability to allow fluoropolymers to be fully recycled. 相似文献
994.
Dr. Yibo Liu Prof. Juewen Liu 《Chembiochem : a European journal of chemical biology》2023,24(2):e202200564
Uric acid is the end-product of purine metabolism in humans and an important biomarker for many diseases. To achieve the detection of uric acid without using enzymes, we previously selected a DNA aptamer for uric acid with a Kd of 1 μM but the aptamer required multiple Na+ ions for binding. Saturated binding was achieved with around 700 mM Na+ and the binding at the physiological condition was much weaker. In this work, a new selection was performed by alternating Mg2+-containing buffers with Na+ and Li+. After 13 rounds of selection, a new aptamer sequence named UA-Mg-1 was obtained. Isothermal titration calorimetry confirmed aptamer binding in both selection buffers, and the Kd was around 8 μM. The binding of UA-Mg-1 to UA required only Mg2+. This is an indicator of successful switching of metal dependency via the salt-toggled selection method. The UA-Mg-1 aptamer was engineered into a fluorescent biosensor based on the strand-displacement assay with a limit of detection of 0.5 μM uric acid in the selection buffer. Finally, comparison with the previously reported Na+-dependent aptamer and a xanthine/uric acid riboswitch was also made. 相似文献
995.
Polylactic acid (PLA) is known as one of the greatest promising bioabsorbable and compostable polyesters with the capability of high molecular weight synthesis. Lactic acid condensation, azeotropic dehydration, and condensation ring-open polymerize of lactide are three methods for PLA polymerization. Comprehension of material properties is critical for choosing the right processing method and adjusting PLA characteristics. A variety of mechanical properties of this material, from soft and elastic to stiff and high strength makes PLA suitable for a wide range of applications. Besides, PLA can be blended or copolymerized with other polymeric or non-polymeric substances. Thus, this polymer can achieve suitable chemical, mechanical, and rheological properties. Understanding the role of these properties and selecting a suitable processing technique is necessary for its intended consumer and various applications. This study elaborated a general summary of the polymerization, processing, and characteristics of PLA (i.e., structural diversities, rheological performances, mechanical properties, and permeability). Besides, this work presented some information regarding essential factors that can be used for modifying PLA properties to address the requirements for various applications such as biomedical, food packing, biocomposite, and additive manufacturing. 相似文献
996.
Yingchun Sun Ru Liu Jianfeng Xu Yuhui Sun Jingya Gong Ling Long 《Polymer Engineering and Science》2023,63(4):1274-1288
A durable and environmentally-friendly superhydrophobic coatings for liquid-food residue reduction were prepared by using stearic acid (SA) modified organic montmorillonite (SA@OMMT) and poly(dimethylsiloxane) (PDMS). Due to the natural hydrophobicity of SAs, SA@OMMT provides low surface energy as well as roughness for the coating. PDMS not only provided low surface energy in the coating but also contributed to the bonding of SA@OMMT as a result of its high adhesive properties. In addition, PDMS has good physical properties after curing, which can effectively improve the physical properties and durability of a superhydrophobic coating by the self-assembly method using a PDMS/n-hexane solution. For 1 wt.% SA@OMMT and 5 wt.% PDMS, the resulting SA@OMMT/PDMS (SOP) coating showed the water contact angle (WCA) and water sliding angle (WSA) of 156.3°and 2°, respectively. The prepared coatings have good physical and chemical stability, and they still have superhydrophobicity after physical abrasion tests and exposure to the corrosion solutions. In the meanwhile, the prepared coating also has flexibility and superhydrophobicity after bending and folding. Finally, the coating surface shows highly effective antifouling ability to liquid and solid pollutants. The coating can be applied against different substrates and has potential application in the field of liquid-food residue reduction. 相似文献
997.
Yanzhen Zhao Jianghao Yan Liu Yang Meirong Xu Huifang Wang Baolong Niu Wenfeng Li 《乙烯基与添加剂工艺杂志》2023,29(1):5-16
Food spoilage caused by bacterial growth is a serious threat to human health, so food preservation technology with long-acting antibacterial effect has been widely studied. In this work, (Cu2O-Ag)@TA heterojunction composite antibacterial material with a core-shell structure was synthesized to improve the stability of Cu2O. Morphological characterization shows that silver nanoparticles are uniformly distributed on the surface of Cu2O microspheres, (Cu2O-Ag)@TA has a core-shell structure, the particle size is about 300 nm, and the thickness of the tannic acid shell is about 6 nm. In addition, (Cu2O-Ag)@TA exhibits excellent dispersibility and stability, it can stably release Cu2+ within 14 days and has enhanced reactive oxygen species release performance, thus achieving excellent antibacterial properties, with a minimum inhibitory concentrations of 96 μg ml−1 against Escherichia coli and Staphylococcus aureus. In addition, adding (Cu2O-Ag)@TA into the LbL-PVA/CS/FA composite film can improve the mechanical properties and antibacterial ability of the composite film, providing a feasible solution for new biodegradable antibacterial packaging materials. 相似文献
998.
Meng Liao Xiang Zhou Lu Fu Liumi Deng Zongmin Zhu Luoxin Wang Shaohua Chen Yuansen Liu 《乙烯基与添加剂工艺杂志》2023,29(1):188-201
Poly(lactic acid) (PLA) has evolved into a commodity polymer with numerous applications. However, its high flammability limits its viability as a perfect alternative to petrochemical engineering plastics. In this study, PLA was modified using polyhexamethyleneguanidine phosphate (PHMG-P) and ammonium polyphosphate (APP). The flame retardant performance of PLA/PHMG-P/APP was investigated based on the limiting oxygen index (LOI), vertical burning test (UL-94), thermogravimetric analysis (TGA), cone calorimetry (CC), scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), and Raman Spectrometry. Qualitative and quantitative methods were used to determine the antibacterial properties of PLA composites. The LOI of PLA-10% (P:A = 1:4) was 31.7% and was rated V-0 in the UL-94 V-0 test. The antibacterial properties of the composites reflected the antibacterial effects of PLA-10% (P: A = 1:4) against Escherichia coli and Staphylococcus aureus, with the antibacterial rates reaching 93.41% and 93.26%, respectively. PHMG-P and APP had a synergistic flame-retardant effect and improved the flame retardancy of PLA while exhibiting excellent antibacterial properties. 相似文献
999.
Mehmet Musa Özcan Nurhan Uslu Viktar Lemiasheuski Duygu Akçay Kulluk Sait Gezgin 《Journal of the American Oil Chemists' Society》2023,100(5):403-412
The physico-chemical properties, phytochemicals, mineral contents of tobacco (Nicotiana tabacum L.) seeds grown at Samsun province in Turkey were evaluated. The oil contents of tobacco seeds ranged from 20.6% (control) to 29.0% (microwave-roasted). L*, a* and b* values of tobacco seeds ranged from 32.38 to 35.61; from 6.32 to 6.78; from 13.72 to 14.27, respectively. Total phenolic contents of tobacco seed extract and oils were reported between 31.02 (oven-roasted) and 34.42 mg GAE/100 g (microwave-roasted) to 4.60 (microwave-roasted) and 6.45 mg GAE/100 g (oven-roasted), respectively. Total flavonoid values of raw and roasted tobacco seed extract and oils were determined between 26.62 (oven) and 67.10 mg/100 g (control) to 21.57 (control) and 44.71 mg/100 g (microwave-roasted), respectively. Gallic acid, 3,4-dihydroxybenzoic acid and catechin are the predominant phenolic components of raw and roasted tobacco seed oils. The amounts of oleic and linoleic acid in raw and roasted tobacco seed oils ranged from 10.23% (oven-roasted) to 12.48% (control) and 73.72% (control) to 76.63% (oven-roasted), respectively. The abundant elements found in seeds were K, P, Ca, Mg, S and Fe. The mineral amounts of the roasted seeds were found higher than that of the control. The highest increase was detected in oven roasted tobacco seeds. 相似文献
1000.
Hui Su Yoon Yu Jin Lee Byung Hee Kim Yangha Kim In-Hwan Kim 《Journal of the American Oil Chemists' Society》2023,100(3):215-224
γ-Linolenic acid (GLA) rich triacylglycerol (TAG) was successfully synthesized from glyceride, instead of glycerol, and fatty acid (FA) via Lipozyme TL IM-catalyzed esterification as a novel strategy. In the first step, GLA was enriched into glyceride fraction from borage oil by Candida rugosa lipase-catalyzed hydrolysis. The glyceride was separated from the reaction mixture by molecular distillation. GLA was enriched from 20.64% in borage oil to 45.94% in the glyceride fraction under optimum conditions. In the second step, the Lipozyme TL IM-catalyzed synthesis of TAG was carried out with the glyceride, and the FA obtained by saponification of a portion of the glyceride. The optimum conditions were the temperature of 50°C, the enzyme loading of 10%, and the vacuum level of 20 mmHg, respectively. The maximum TAG content of approximately 92% was achieved after 12 h under the optimum conditions. 相似文献