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151.
152.
Fatty Acid and Lipid Profiles with Emphasis on n-3 Fatty Acids and Phospholipids from Ciona intestinalis
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In order to establish Ciona intestinalis as a new bioresource for n‐3 fatty acids‐rich marine lipids, the animal was fractionated into tunic and inner body tissues prior to lipid extraction. The lipids obtained were further classified into neutral lipids (NL), glycolipids (GL) and phospholipids (PL) followed by qualitative and quantitative analysis using GC‐FID, GC–MS, 1H NMR, 2D NMR, MALDI‐TOF‐MS and LC–ESI–MS methods. It was found that the tunic and inner body tissues contained 3.42–4.08 % and 15.9–23.4 % of lipids respectively. PL was the dominant lipid class (42–60 %) irrespective of the anatomic fractions. From all lipid fractions and classes, the major fatty acids were 16:0, 18:1n‐9, C20:1n‐9, C20:5n‐3 (EPA) and C22:6n‐3 (DHA). The highest amounts of long chain n‐3 fatty acids, mainly EPA and DHA, were located in PL from both body fractions. Cholestanol and cholesterol were the dominant sterols together with noticeable amounts of stellasterol, 22 (Z)‐dehydrocholesterol and lathosterol. Several other identified and two yet unidentified sterols were observed for the first time from C. intestinalis. Different molecular species of phosphatidylcholine (34 species), sphingomyelin (2 species), phosphatidylethanolamine (2 species), phosphatidylserine (10 species), phosphatidylglycerol (9 species), ceramide (38 species) and lysophospholipid (5 species) were identified, representing the most systematic PL profiling knowledge so far for the animal. It could be concluded that C. intestinalis lipids should be a good alternative for fish oil with high contents of n‐3 fatty acids. The lipids would be more bioavailable due to the presence of the fatty acids being mainly in the form of PL. 相似文献
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Yan Weng Fang Li Wei Chen Yuqiang Miao Xing Tang 《European Journal of Lipid Science and Technology》2010,112(11):1190-1199
This study focused on the degradation kinetics of bufalin (B), cinobufagin (C), and resibufogenin (R) in bufadienolides‐loaded lipid microsphere (BU‐LM) and bufadienolides‐loaded aqueous solution (BU‐S). The chemical stability of bufadienolides both in BU‐LM and BU‐S at different pH values and temperatures was monitored by HPLC. Photon correlation spectroscopy and electrophoretic light scattering technology were used to evaluate the physical characteristic of BU‐LM. Under the most stable pH range of 6.0–6.5, the half‐lives of B, C, and R in BU‐LM were 22, 15, and 20 days at 80 °C but 4510, 1717, and 3300 days at 25 °C, whereas for BU‐S only 11, 3, and 10 days at 80 °C and 71, 18, and 49 days at 25 °C. The results indicated that BU‐LM significantly increased the chemical stability of bufadienolides, especially at low temperatures. The degradation of bufadienolides took place mostly in the aqueous phase and the diffusion process of bufadienolides from the oil phase through the interfacial layer to the aqueous phase was the rate‐limiting step for the drug degradation. A low temperature slowed down of the diffusion rate leading to a slower degradation and longer half‐lives. Among the three bufadienolides in BU‐LM, C was protected from degradation to the greatest extent. Practical applications : Bufadienolides, consisting of bufalin (B), cinobufagin (C), and resibufogenin (R) have poor aqueous solubility between 20 and 60 µg/mL and are easily degradable by acids or bases. Here we propose a new strategy to overcome stability problems by using lipid microspheres (LM) as the drug vehicle. By incorporating the drugs into the interior oil phase and the oil–water interfacial film, a direct contact of the drug with body fluids and tissues is avoided. Thus the drug is protected from degradation and possible side effects are minimized. Our results indicate that BU‐LM significantly increased the chemical stability of bufadienolides, especially at low temperatures. Among the three bufadienolides in BU‐LM, C was protected from degradation to the greatest extent. 相似文献
156.
Munikumar R. Doddareddy Dr. Elisabeth C. Klaasse Dr. Shagufta Dr. Adriaan P. IJzerman Prof. Andreas Bender Dr. 《ChemMedChem》2010,5(5):716-729
Ligand‐based in silico hERG models were generated for 2 644 compounds using linear discriminant analysis (LDA) and support vector machines (SVM). As a result, the dataset used for the model generation is the largest publicly available (see Supporting Information). Extended connectivity fingerprints (ECFPs) and functional class fingerprints (FCFPs) were used to describe chemical space. All models showed area under curve (AUC) values ranging from 0.89 to 0.94 in a fivefold cross‐validation, indicating high model consistency. Models correctly predicted 80 % of an additional, external test set; Y‐scrambling was also performed to rule out chance correlation. Additionally models based on patch clamp data and radioligand binding data were generated separately to analyze their predictive ability when compared to combined models. To experimentally validate the models, 50 of the predicted hERG blockers from the Chembridge database and ten of the predicted non‐hERG blockers from an in‐house compound library were selected for biological evaluation. Out of those 50 predicted hERG blockers, tested at a concentration of 10 μM , 18 compounds showed more than 50 % displacement of [3H]astemizole binding to cell membranes expressing the hERG channel. Ki values of four of the selected binders were determined to be in the micromolar and high nanomolar range (Ki (VH 01 )=2.0 μM , Ki (VH 06 )=0.15 μM , Ki (VH 19 )=1.1 μM and Ki (VH 47 )=18 μM ). Of these four compounds, VH 01 and VH 47 showed also a second, even higher affinity binding site with Ki values of 7.4 nM and 36 nM , respectively. In the case of non‐hERG blockers, all ten compounds tested were found to be inactive, showing less than 50 % displacement of [3H]astemizole binding at 10 μM . These experimentally validated models were then used to virtually screen commercial compound databases to evaluate whether they contain hERG blockers. 109 784 (23 %) of Chembridge, 133 175 (38 %) of Chemdiv, 111 737 (31 %) of Asinex and 11 116 (18 %) of the Maybridge database were predicted to be hERG blockers by at least two of the models, a prediction which could, for example, be used as a pre‐filtering tool for compounds with potential hERG liabilities. 相似文献
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158.
Isabel Medina M. Jesús González Manuel Pazos Dorotea Della Medaglia Raffaele Sacchi José Manuel Gallardo 《European Food Research and Technology》2003,217(4):301-307
The ability of antioxidants obtained from natural sources to stabilise foodstuffs containing long n-3 fatty acids of marine origin has been determined. Food systems enriched in polyunsaturated fatty acids (PUFA) were: emulsified horse mackerel (Trauchurus trauchurus) muscle, fish oil-in-water emulsions (4% of n-3 PUFA) and fish oils (40% of n-3 PUFA). Rosemary leaves and extra virgin olive oil (EVO) were employed as sources of natural phenolic antioxidants. Both vegetable extracts were able to retard lipid oxidation in the different lipid systems. Rosemary extracts with a high content of carnosoic acid showed a significant synergism with fish proteins, by reinforcing their antioxidative effectiveness. Fish proteins and EVO-phenolics showed minor cooperative effects for inhibiting oxidation. The antioxidative partition into the different phases in the emulsified systems showed minor amounts of phenolics in the aqueous phases, except hydroxytyrosol and tyrosol, and a high adsorption on fish muscle.An erratum to this article can be found at 相似文献
159.
The purpose of this study was to evaluate if continuous non-vacuum or vacuum tumbling improves the quality of roast beef utilizing the one location injection. Basically, fresh roast beef treated by one location injection with tumbling had significantly different quality compared to non-tumbled ones. However, the cooked roast beef did not significantly exhibit better quality due to tumbling. There was insignificant difference of TBARS value for whole meat among treatments at day 0. The control had significantly higher TBARS value compared to roast beef with non-vacuum and vacuum tumbled samples at day 2. At 4, 7 and 14 days of refrigerated storage, the control maintained the significantly highest values when compared to the other treatments that had similar TBARS values. The addition of three antioxidants was the major contributor to lipid stability of the cooked roast beef. 相似文献
160.
随着仪器性能的不断提高,飞行时间二次离子质谱(TOF-SIMS)在材料表面化学分析中起着越来越重要的作用。TOF-SIMS的主要测试功能包括表面质谱、化学成像及深度剖析,本工作对TOF-SIMS的化学成像及深度剖析2种功能在生物材料和生命科学中的应用做了简单综述,重点介绍了TOF-SIMS成像技术在生物芯片制备工艺中的应用和TOF-SIMS成像和深度剖析技术对生物分子在细胞和生物体组织上空间分布的表征方法;另外,对生物样品的低温制备方法,样品表面添加基质以增强信号强度的实验手段,使用团簇一次离子源提高分子二次离子产额和利用对样品损伤小的C60离子源为轰击源做深度剖析等实验做了简单的介绍;最后,对TOF-SIMS在生物生命材料领域的应用做了展望。 相似文献