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排序方式: 共有497条查询结果,搜索用时 15 毫秒
1.
Wenjie Liu Jianmin Liu Shu Xing Xiaobin Li Liwen Han Kechun Liu Tao Wei Mingyang Zhou 《European Journal of Lipid Science and Technology》2021,123(6):2000276
In this study, the anti-atherosclerotic properties of three marine phospholipids (MPLs) extracts from fishery by-products including codfish roe, squid gonad, and shrimp head are verified. Their effects on key factors involved in atherosclerosis are examined and compared to explore whether the differences in their constitutions lead to the differences in the function. All three MPLs dampen oxidation of low- density lipoproteins (LDL) in vitro. Treating RAW264.7 macrophages and HUVECs endothelial cells with each MPLs ranging 10–100 µg mL−1 does not decrease cell viability, yet ox-LDL caused cytotoxicity of both cells are alleviated by 50 or 100 µg mL−1 MPLs treatment. In addition, the three MPLs reduce ox-LDL induced macrophage foam-like transition, mainly through inhibition of lipid uptake. Of the three MPLs, the one from squid gonad exhibits the best effect. On the other hand, all three MPLs modulate inflammatory responses, equally, by inhibiting the adhesion of monocytes to endothelial cells, and decreasing secretion of pro-inflammatory cytokines IL-6 and MCP-1. Using a high-cholesterol diet induced zebrafish model, it is found that all three MPLs, especially the one from squid gonad, alleviates cholesterol accumulation in early plaques, and decreases total cholesterol as well as lipid peroxide in vivo. Practical Applications: As a way of making the best of the increasingly scarce marine resources, valuable lipid components can be recovered from by-products and wastes from the fishery industry. Here, we tested the anti-atherosclerotic effects and the mechanisms of three MPLs extracted from codfish roe, squid gonad, and shrimp head. Our study provides further evidence that marine phospholipids extracted from fishery by-products could protect against atherosclerosis, and helps to elucidate the structure-function relationship of MPLs. 相似文献
2.
Niu Zhang Cheng‐Fei Zhuo Biao Liu Wen‐Hui Ye Lin Tao Liu‐Feng Zheng Li Chen Ze‐Yuan Deng Guo‐Yong Li Zhi‐Qing Gong Jing Li 《European Journal of Lipid Science and Technology》2020,122(3)
Phospholipids (PLs) and cholesterol in human milk (HM) are affected by lactation, and differential lipids are closely related to maternal diet. The contents of PLs and cholesterol in Chinese HM are quantified by gas chromatography and high performance liquid chromatography, respectively, and the relationship between differential lipids and the maternal diet is obtained by Pearson. The result shows that SFA, MUFA, and polyunsaturated fatty acid (PUFA) are not affected by lactation and geography for total fatty acids, but almost all sn‐2 fatty acids are influenced by geography and remain unchanged during lactation. Most SFAs show absolute sn‐2 selectivity and the majority of MUFAs and PUFAs are esterified at the sn‐1 position. Cholesterol (13.8–22.6 mg per 100 g milk) and 25‐hydroxycholesterol (0.45–1.01 mg per 100 g milk) increase significantly and remain constant during lactation, respectively, and they are affected by regions. In addition, the differential lipids (22:1n‐9, C9:0, trans‐PUFA, 22:4n‐6, etc.) of PLs are closely related to the maternal diet. PLs and cholesterol content differ from western research and infant formula, which will help to design an infant formula that is more suitable for Chinese babies in the future. Practical Application: Compared with PLs and cholesterol in western countries and infant formula, the specificity of Chinese HM can more accurately target the development of formulas suitable for the growth of Chinese infants. At the same time, according to the influence of the mother?s diet on the composition of HM, it is more reasonable to guide the diet of the mother. 相似文献
3.
Michelle Pinault Cyrille Guimaraes Jean‐Franois Dumas Stphane Servais Stephan Chevalier Pierre Besson Caroline Goupille 《European Journal of Lipid Science and Technology》2020,122(2)
The aim of this study is to identify high performance thin layer chromatography (HPTLC) conditions allowing the separation and quantification of mammalian cellular phospholipids (PLs) (sphingomyelin, phosphatidylcholine, phosphatidylserine, phosphatidylinositol, phosphatidylethanolamine, and especially phosphatidic acid, cardiolipin, and monolysocardiolipin, these latter two being specifically located in mitochondria membranes). In order to make this method faster and easier, a 1D HPTLC method is chosen, testing several eluents as well as several staining methods. A pre‐conditioning of HPTLC plates with boric acid and a copper staining reagent followed by carbonization are selected for the quality of PL separation and homogeneity of staining. The selected conditions are discussed and the method validation is performed according to the International Conference on Harmonization guidelines. Linearity is effective between 1 and 8 µg and limit of quantification is between 0.5 and 2.3 µg depending on PL classes. Precision measurements show coefficients of variation <6%, and when amounts are close to the detection limit, <12%. Lipid extracts of tumor cell lines or isolated mitochondria are used to assess PL profiles. This shows that the HPTLC method can be used routinely to follow level variations of PLs. Practical Applications: The changes in PL composition play a crucial role in tumor processes and regulate cellular functions modulating cellular signaling or mitochondrial metabolism. The simple and cost‐effective 1D HPTLC method that is developed is applied to lipid extracts of whole tumor cells or hepatocyte‐isolated mitochondria. It is sensitive as well as precise to detect variations of phosphatidic acid or cardiolipin levels linked to physio‐pathological conditions. It can also be used to investigate the composition changes of other membrane PLs. Moreover, with a simultaneous analysis of 14 samples/standards on the same plate (six plates per day), this method is adapted for large series of samples. 相似文献
4.
5.
为了将大豆浓缩磷脂更好的应用到乳化炸药中,研究以大豆浓缩磷脂为原料,在真空加热搅拌条件下与改性试剂A反应后加碱中和,再经真空干燥使水分含量≤1%制成改性磷脂。探讨改性磷脂替代50%的Span80制成复合乳化剂在乳化炸药中应用,通过对复合乳化剂制备的乳化炸药基质中游离铵含量、粒子形状和粒径大小、储藏时间等分析测定,评价对其稳定性及爆炸性能的影响。在小试基础上应用于中试生产中,并进行乳化炸药的爆炸和60 d储藏实验,结果表明:殉爆距离5 cm 3/3、爆速4630 m·s-1、猛度11.0 mm等性能指标均达到国家标准(GB18095—2000)中2号岩石乳化炸药的要求。 相似文献
6.
Pravin Kumar Dinesh Kumar Sharma Mahendra Singh Ashawat 《European Journal of Lipid Science and Technology》2021,123(10):2100002
This work aims to develop and evaluate the efficacy of tea tree oil (TTO) ethosomal cream with improved deposition in skin layers for treatment of atopic dermatitis (AD). Ethosomes of TTO are developed using phosphatidylcholine (2% and 3% w/v) and ethanol (20%, 30%, and 40% w/v). Ethosomes are evaluated for percent entrapment efficiency (%EE), vesicle size, zeta potential, and in vitro drug diffusion. Ethosomal creams with optimized ethosomal dispersion are developed and evaluated for physicochemical parameters, thermal stability, ex vivo permeation, skin retention, and in vitro cytotoxicity using HaCat skin cell lines in comparison to conventional creams of TTO. In vivo investigations of optimized creams are performed using BALB/c mice model. The %EE, vesicle size, and zeta potential for optimized ethosomes are found to be 76.19 ± 3.26%, 333.6 nm, and –35.3 mV, respectively. Ethosomal creams showed higher deposition in the epidermis and dermis. The optimized creams are non-cytotoxic to HaCat cell lines. The creams significantly reduce the inflammatory response by decreasing the clinical score and infiltration of white blood cells, eosinophils, and IgE antibodies. Overall efficacy of ethosomal cream is higher than conventional cream. In conclusion, optimized ethosomal cream of TTO shows good efficacy for treatment of AD. Practical applications : The method used for the formulation of ethosomes is simple and can be easily scaled up on the industrial level. The loading of TTO within ethosomes can increase the efficiency by enhanced drug deposition in the epidermis and might also improve its stability against oxidative degradation. Topical ethosomal cream of TTO can improve patient compliance by avoidance of adverse effects linked with corticosteroids and could be a possible complementary or alternative therapy in management of AD. 相似文献
7.
Anna F. Horn Nina S. Nielsen Charlotte Jacobsen 《International Journal of Food Science & Technology》2012,47(5):1097-1108
The objective of this study was to investigate the protective effect of five different emulsifiers on iron‐mediated lipid oxidation in 70% fish oil‐in‐water emulsions. The emulsifiers were either based on protein (whey protein isolate and sodium caseinate) or based on phospholipid (soy lecithin and two milk phospholipids with different phospholipid contents, MPL20 and MPL75). Lipid oxidation was studied at pH 4.5 and 7.0, and results were compared to lipid oxidation in neat fish oil. Results showed that all emulsions oxidised more than neat oil. Furthermore, emulsions prepared with proteins oxidised more at low pH than at high pH, and casein emulsions oxidised the least (Peroxide value (PV) at day 7 was 0.5–0.7 meq kg?1). Among emulsions prepared with phospholipids, emulsions with MPL75 were the most oxidised followed by emulsions prepared with lecithin and MPL20. Thus, PV in MPL75 emulsions was 5.0–5.5 meq kg?1 at day 7 compared with 0.9–1.9 meq kg?1 in MPL20 emulsions. 相似文献
8.
利用三重四极杆质谱碰撞能量自动优化功能,在正、负离子检测模式下,对磷脂标准品(包括PA,PC,PE,PS,PG,PI)不同碰撞能量下子离子的裂解规律进行研究。实验发现:在负离子模式下,各类磷脂的子离子[M-H-R2COOH]-强度总是高于[M-H-R1COOH]-强度,而[M-H-R’2CH=CO]-丰度总是高于[M-H-R’1CH=CO]-丰度,这个规律可以用于确定左右磷脂的酰基位置。另外,在负离子模式下,PA和PS母离子裂解产生的羧酸阴离子丰度比均为R1COO-高于R2COO-,PC则为R1COO-低于R2COO-;在正离子模式下,PS裂解产生的酰基阳离子R1CO+丰度总是低于R2CO+,PA和PC在低碰撞能量下,sn-1脂肪酰基基团作为烯酮的中性丢失而产生离子丰度总是低于sn-2位上产生的对应离子;而PE和PG的sn-1位脂肪酰基基团作为羧酸的中性丢失而产生的离子在低碰撞能量下的丰度高于sn-2位上产生的离子。这些规律可用于辅助确定磷脂脂肪酰基的位置。 相似文献
9.
Antoine Diguet Maël Le Berre Yong Chen Damien Baigl 《Small (Weinheim an der Bergstrasse, Germany)》2009,5(14):1661-1666
By dragging a phospholipid solution on microstructured silicon surfaces, phospholipid molecules are selectively deposited inside the microstructures to get regular phospholipid multilayer patterns of controlled thickness over a large scale (~cm2). By varying the dragging speed, the thickness of the patterns varies between 28 and 100 nm on average (7 to 25 bilayers). Electroswelling of phospholipid multilayer patterns leads to the formation of giant liposomes of controlled size and narrow size distributions. 相似文献
10.
Tong Wang Earl G. Hammond Walter R. Fehr 《Journal of the American Oil Chemists' Society》2001,78(11):1139-1144
Soybeans with modified saturated fatty acid compositions sometimes have lower seed germination rate or other undesirable agronomic
traits. To determine if seed germination could be related to the melting transitions of their lipids, triacylglycerols (TAG)
and phospholipids (PL) from soybeans with a wide range of saturated fatty acid compositions were examined by differential
scanning calorimetry. The melting transition temperatures of both TAG and PL increased with increasing palmitate and stearate
percentages. The mean melting points of the various lipids calculated on the basis of the melting points of their fatty acids
correlated with the observed transition temperatures. Increased lipid saturation and elevated phase transition temperatures
may have contributed to the reduced germination and seedling growth rates of these modified seeds. 相似文献