Inhibition of leukocyte 5-lipoxygenase by phenolics from virgin olive oil

Interest in the health-promoting effects of virgin olive oil, an important part of the 'Mediterranean diet', prompted us to determine the anti-eicosanoid and antioxidant effects in leukocytes of the principal phenolic compounds from the 'polar fraction': oleuropein, tyrosol, hydroxytyrosol, and caffeic acid. In intact rat peritoneal leukocytes stimulated with calcium ionophore, all four phenolics inhibited leukotriene B4 generation at the 5-lipoxygenase level with effectiveness hydroxytyrosol > oleuropein > caffeic acid > tyrosol (approximate EC50 values: 15, 80, 200, and 500 microM, respectively). In contrast, none of these compounds caused substantial inhibition of thromboxane generation via the cyclo-oxygenase pathway. Hydroxytyrosol, caffeic acid, oleuropein, and tyrosol (decreasing order of effectiveness) also quenched the chemiluminescence signal due to reactive oxygen species generated by phorbol myristate acetate-stimulated rat leukocytes. None of these compounds were toxic to leukocytes at the concentrations tested. We conclude that the phenolics found in virgin olive oil possess an array of potentially beneficial lipoxygenase-inhibitory, prostaglandin-sparing, and antioxidant properties.     

Compound A: solubility in saline and olive oil; destruction by blood

Compound A is a degradation product of sevoflurane. Knowledge of the solubility of Compound A, CH2F-O-C(=CF2)(CF3), in blood and other solvents would aid in the definition of its kinetics. Accordingly, we determined solvent/gas partition coefficients of Compound A for saline (0.166 +/- 0.002 [mean +/- SD; n = 4]) and olive oil (20.1 +/- 1.1 [n = 4]). Measurement of solubility in blood was confounded by degradation of Compound A in blood and blood components. If a mixture of 99.3% saline and 0.7% oil provides the solubility equivalent to that possessed by blood (as it does for the parent compound, sevoflurane), then blood solubility and solubility in plasma, albumin, red blood cells, or pure hemoglobin is approximately 0.31. The order of Compound A degradation was human plasma = rat blood > whole human blood >5% human serum albumin = washed human red blood cells (hematocrit 50%) = 5% pure hemoglobin. Presuming a solvent/gas partition coefficient of 0.31, respective approximate times for 50% degradation equaled 2.7, 2.8, 4.6, 9.9, 11.0, and 12 min. The accuracy of these approximations was limited by the need to estimate, rather than determine, the solubility of Compound A in such solvents. Pasteurization (heating to 60 degrees C for 12 h) or pretreatment with N-ethylmaleimide (a compound that reversibly binds to sulfhydryl groups) decreased the degradation rate in plasma. These results suggest that degradation arises, at least in part, from reaction of Compound A with proteins in blood, possibly from covalent reaction of Compound A with protein and/or from an enzymatically mediated reaction. The products of degradation, the binding sites, and the clinical implications of such binding and degradation remain to be determined.     

Migration testing with olive oil in a microwave oven

A study was carried out to compare the overall migration from packaging materials into olive oil during heating in a microwave oven, and the overall migration from the same materials into olive oil but applying time and temperature conditions stipulated in the current EC and Dutch legislation on food packaging. Application of additional test conditions (e.g. 30 min and 1 h in combination with test temperatures exceeding 121 degrees C, and a test temperature of 130 degrees C) have demonstrated the need for extension of the test conditions mentioned in existing food packaging regulations to enable realistic migration testing of microwave packaging materials under conventional test conditions. It is concluded that the overall migration into olive oil from packaging materials intended for microwave oven use, including susceptor materials, can be judged on the basis of migration testing using conventional heating. For testing film or susceptor materials in a microwave oven by one-sided contact, a migration cell transparent to microwaves was developed and used up to 200 degrees C. In conventional high-temperature tests applying hot-filling of trays or migration cells, a temperature drop was observed, while handling oil at temperatures of 150 degrees-175 degrees C may be considered perilous. To prevent problems of this kind it is proposed to start migration tests at room temperature and to heat the simulant rapidly to the final test temperature. This procedure is comparable to migration tests carried out with aqueous food simulants at 121 degrees C in an autoclave.(ABSTRACT TRUNCATED AT 250 WORDS)     

Effect of olive oil on immune function in middle-aged men

Autocrine motility factor is a tumor-secreted cytokine which regulates cellular growth and motility by a receptor-mediated pathway. In the accompanying report (Part I of II), it was demonstrated that high (K1735-M1) and low (K1735-C1.11) metastatic murine melanoma cells display distinct adhesion and spreading characteristics which correlate with their differential spontaneous and stimulated migrations on the extracellular matrix components fibronectin, laminin and collagen IV. These parameters were further related to discrete profiles of focal adhesion plaque integrity and reorganization. Here we describe unique migration patterns observed in these murine melanoma cells which reflect differences in degradation and/or remodeling of the cellular substratum. These profiles of matrix interaction were influenced distinctly by autocrine motility factor and dictated by both substrate composition and cellular phenotype. Since activation of the autocrine motility factor receptor stimulates invasion of a reconstituted basement membrane and enhances experimental metastasis by high- but not low-metastatic K1735 cells, differences in the invasive phenotypes of these cells may be due in part to their differential responses to external stimuli coupled with internal propensities toward either matrix degradation and migration (high-metastatic cells) or matrix remodeling and stasis (low-metastatic cells).     

Effect of isoenergetic replacement of starch by olive oil and fish oil concentrations of lipids in plasma and lipoprotein fractions in swine

Two experiments with sows were performed to investigate the effect of isoenergetic replacement of starch by fish oil or olive oil on concentrations of lipids in plasma and lipoproteins. The first experiment was based on a cross-over design with three periods, each lasting 16 days. Each sow was fed during one of the periods a basal ration with isoenergetic addition of (1) starch (495 g/d), (2) olive oil (221 g/d), or (3) fish oil (223 g/d) based on energetic requirement for maintainance. The second experiment was based on a cross-over design with eight periods, each lasting 16 days. In the first and in the last periods, each sow was fed the basal ration. In the other six periods, each sow was fed the basal ration with addition of two different amounts of (1) starch (284/568 g/d), (2) olive oil (140/281 g/d), or (3) fish oil (141/282 g/d). The two different amounts of addition were selected to exceed the energetic requirement for maintainance by 25% or 50%. In both experiments blood samples were taken before each change of the ration. In both experiments olive oil elevated the concentration of cholesterol in plasma in comparison with starch. This elevation was due to a large elevation in high-density lipoproteins (HDL), and a slight elevation in low-density lipoproteins (LDL) and very-low density lipoproteins (VLDL). The ratio between HDL and LDL cholesterol was increased by feeding olive oil. The effect of olive oil on concentrations of cholesterol in plasma and lipoproteins was dose-dependent. In both experiments none of the two dietary oils significantly changed concentrations of triglycerides in plasma and lipoproteins. Concentrations of phospholipids in plasma, HDL, and LDL were elevated by olive oil. In both experiments addition of fish oil elevated concentration of cholesterol in plasma due to elevated cholesterol concentration in LDL. Concentration of HDL cholesterol was not changed by fish oil. Thus, the ratio between HDL cholesterol and LDL cholesterol was lowered by fish oil. The effect of fish oil on concentration of cholesterol in plasma and lipoproteins was also dose-dependent. Fish oil had no significant effect on phospholipid concentrations in plasma and lipoproteins. In conclusion, in the present experiment olive oil caused antiatherogenic changes of the lipoprotein profile, whereas fish oil caused proatherogenic changes of the lipoprotein profile.     

红外分光光度法测定焦化废水中油

针对焦化废水处理站实际生产需要,建立了焦化废水中油的红外分光光度测定方法。探讨了NaCl和无水Na2SO4用量、CCl4定容等条件对测定结果的影响。结果表明,由于焦化废水中油乳化程度较低,可以用盐酸酸化破乳,在用CCl4萃取水中油时不需加电解质NaCl;加2g无水Na2SO4能使25mLCCl4萃取液脱水完全;萃取后的CCl4相不必定容可以直接进行测定。本方法对焦化废水中油进行测定,加标回收率93%～105%,相对标准偏差2.5%～8.7%。     

全自动顺序喷油润滑装置在熟料窑系统的开发应用

本文主要介绍了全自动顺序喷油润滑装置在熟料窑系统的开发应用，实现了熟料窑系统润滑的自动化，改进了润滑方式，提高了润滑效果，降低了油耗，减轻了工人的劳动强度。     

Modification of cesium toxicity by calcium in mammalian system

The interaction between cesium chloride CsCl and calcium chloride CaCl2 was observed in bone marrow chromosomes of mice. The two salts were administered orally to laboratory bred Swiss albino mice in vivo singly or one followed by the other, or both simultaneously. CsCl induced chromosomal aberrations in frequencies directly proportional to the dose administered. The frequency of aberrations was reduced significantly when the two chemicals were administered simultaneously or when CaCl2 was given 2 h before CsCl. Thus, CaCl2 is able to protect against the cytotoxicity of CsCl.     

微波等离子体炬原子发射光谱法测定原油中钙

微波等离子体炬原子发射光谱法(MPT-AES)是利用微波源提供能量,其与电感耦合等离子体原子发射光谱法(ICP-AES)特点类似,具有原子化效率高、分析速度快和操作简单等优点,但是目前对该技术的应用研究仅限于仪器工作条件的优化,对某些共存元素的干扰缺乏有效的解决措施。实验以氩气为载气和工作气,详细考察了MPT-AES测定原油中钙的工作条件和共存元素对钙测定的影响。结果表明,选择Ca 393.366nm为分析谱线,微波功率为85 W,载气流量为1 350 mL/min,工作气流量为650 mL/min,钙质量浓度在0.010~6.00μg/mL范围内与其对应的发射强度呈线性,线性相关系数r=0.999 8;方法中钙的检出限为5.6×10-3μg/mL。干扰试验结果表明,7倍于钙质量浓度的钠,3倍于钙质量浓度的铁、钴,1倍于钙质量浓度的镁、铜、铝不影响钙的测定;1倍于钙质量浓度的钒、镍干扰钙的测定。在0.5mL 5g/L EDTA和0.5mL 10g/L邻菲罗啉溶液的联合作用下,可使铝、钴、镍、镁、铁、铜、钒的允许量至少提高到5倍。将实验方法应用于原油中钙的测定,测定结果与火焰原子吸收光谱法(FAAS)基本一致,相对标准偏差(RSD,n=6)为1.6%~2.2%。     

Low pH enhances the transfer of carotene from carrot juice to olive oil

A current model for carotenoid transport and absorption in the gut proposes an initial solubilization in the oil phase of dietary emulsions followed by incorporation of the carotenoids in mixed bile salt micelles. To assess the relevance of the first stage of this model to what is observed in vivo we have examined the transfer of carotene from carrot juice to olive oil. Increased acidity enhanced the transfer from both whole juice and carotene crystals isolated from carrot chromoplasts. The transfer was significantly slower from whole juice. By using exogenous beta-carotene and measuring its transfer to oil in the presence and absence of carrot juice we have demonstrated that the inhibition of the transfer in juice arises, at least in part, from soluble juice factors. The inhibition is relieved by a fall in pH, which leads to lowering of the electric potential at the oil/aqueous phase interface and aggregation of carrot tissue including crystalline carotene. Under conditions of low pH, oil droplets adhere to the tissue aggregates, allowing carotene to pass into the oil. Our results provide an explanation for why carotene absorption in vivo is depressed by conditions of low gastric acidity.     

Effect of high fat corn oil, olive oil and fish oil on phospholipid fatty acid composition in male F344 rats

Venous stasis associated with prolonged bed rest can enhance the risk of deep venous thrombosis (DVT). Pneumatic compression of the lower extremities can reduce this risk by preventing venous stasis. When selecting a method of leg compression for their patients, physicians must chose between two distinctly different types of compression devices. One device applies pressure with a single-chambered sleeve to the below knee region while the other applies pressure in a sequential gradient fashion from the ankle to the thigh. The current prospective study was designed to evaluated the ability of two such devices to increase blood flow in the profunda femoral vein. Venous blood flow velocity, compression time, and vein diameter were measured in nine normal experimental subjects using an Accuson duplex-Doppler before, during and after leg compression. Compression with the single-chambered device produced a significant rise in venous blood flow velocity; however, this could not be maintained and our results indicate a higher average velocity was achieved with the sequential gradient device. The sequential gradient device also moved a greater volume of blood and achieved a higher average blood flow rate. The time between deflation of the sleeve and return of a phasic respiratory signal was greater after compression with the sequential gradient device. These results suggest that sequential gradient compression produces the type of hemodynamic alterations needed to reduce the risk of DVT by achieving a sustained increase in venous blood flow and more completely emptying of the veins in the leg.     

On the origin of benzene, toluene, ethylbenzene and xylene in extra virgin olive oil

Concentrations of benzene, toluene, C2-benzenes and styrene were determined in olives and the oils produced thereof, as well as at various intermediate steps during production. Concentrations were compared to those found in samples of air taken from the olive grove and the olive mills. In an exposition experiment in the laboratory, olives absorbed aromatic compounds, approaching saturation corresponding to the partition coefficient between air and oil. However, concentrations in olives delivered to the mills were 4-10 times higher than expected from the analysis of the air in the olive grove. In the olive mills, concentrations were increased further by a factor of up to 2 because of uptake from air which contained high concentrations of aromatics. Styrene concentrations strongly increased during storage of crushed olives at ambient temperature, which confirms the hypothesis that styrene is a product of metabolism.     

Homosynaptic facilitation of transmitter release in crayfish is not affected by mobile calcium chelators: implications for the residual ionized calcium hypothesis from electrophysiological and computational analyses

1. Evoked neurotransmitter release at the crayfish neuromuscular junction was measured in the presence of the cell-permeant calcium chelator 1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid-acetotoxymethyl (BAPTA-AM). Excitatory post-synaptic potentials were greatly diminished after application of the intracellular chelator, an effect resulting from attenuation of the rise in the concentration of cytoplasmic Ca2+ ([Ca]i) that is necessary for neurotransmission. However, short-term homosynaptic facilitation of release, the magnitude and time course of which is thought to depend on the accumulation and removal of residual Ca ions (Ca2+), was not affected. Application of the cell-permeant form of ethylene glycol-bis-(beta-aminoethyl ether)-N,N,N',N'-tetraacetic acid (EGTA) gave similar results. 2. To interpret these results we developed a reaction-diffusion model in 3D rectangular coordinates for Ca2+ diffusion in the presence of mobile and immobile buffers. Solutions of the model in response to influx of Ca2+ through one or six channels for different diffusion coefficients and no nondiffusable buffer, predict that 1) the time course of residual Ca2+ is very brief, 2) an unrealistically low Ca2+ diffusion coefficient is required for residual calcium, 3) the spatially distributed Ca2+ signal is attenuated by intracellular BAPTA, 4) the rate at which free Ca2+ returns to resting levels, after entry (residual Ca2+) is faster with more mobile buffer, and 5) when pulse trains of Ca2+ channel current are used as input, computed facilitation is comparable to experimental measurements without buffer, but is abolished in the presence of exogenous buffer. 3. When the diffusion coefficient of Ca2+ in water is used, there is no residual Ca2+; however, when 0.1-1.6 mM nondiffusable buffer is present with a fast binding coefficient comparable to BAPTA, there is a very small residual Ca2+ due to the unbinding from the fixed binding sites. The nondiffusable buffer is saturated next to a Ca2+ channel. For this case of the diffusion coefficient of calcium in H2O and nondiffusable buffer, when a moderate amount of diffusable buffer is added to the system containing nondiffusable buffer, the very small residual Ca2+ is substantially reduced. This is because the product of diffusable buffer and Ca2+ is carried away as diffusable product, in contrast to the nondiffusable product releasing Ca2+, after Ca2+ entry ceases. 4. The model predicts that mobile calcium buffers with appropriate physical properties will attenuate facilitation and hasten its decay by removing residual calcium.(ABSTRACT TRUNCATED AT 400 WORDS)     

Changes in the quality parameters of virgin olive oil from the Lower Aragon area of Teruel during the storage

Virgin olive oil from the Lower Aragon area, despite its excellent alimentary qualities, is a product which is sensitive to high temperatures and sunlight. In this work, during a 10 months storage period, a study was made of the variation in acidity, the index of peroxides, K270 and alpha-tocopherol in two olive oils, one of which was made from fresh olives by means of the traditional oil mill methods, a discontinuous method, and the other oil was obtained from pre-fermented olives by means of the modern centrifugation method, or the continuous method. These parameters were measured in both types of oil, in samples stored at room temperature (variable) and others stored at a constant temperature (20 degrees C + 1 degree C). A sub-sample of each of these was stored in the dark, and another in the presence of light. The variation of the parameters allows us to see the variation which takes place with regard to the nutritive properties of the oil ashen this is stored.     

镧盐增敏-微波等离子炬原子发射光谱法测定原油中钙

以微波等离子炬(MPT)为光源,氩气为载气和工作气体建立起来的微波等离子炬原子发射光谱法(MPT-AES)可以在低激发功率和低工作气体流量下正常工作,具有分析速度快、设备运行成本低和多元素同时测定等优点.但是低功率MPT工作气体温度较低,存在激发能力弱和抗基体干扰能力差等不足.实验针对MPT-AES测定钙中的基体干扰问...     

硫酸钙晶须制备及应用研究进展

硫酸钙晶须是由石膏矿或工业副产品脱硫石膏制备而得,它是一种形貌完整,长径比大,比表面积大,横截面均匀的亚纳米纤维材料,是一种性能良好的改性剂.但是由于当前制备的硫酸钙晶须产率低,质量差等问题,导致硫酸钙晶须在大范围应用上受到一定的限制.文中着重介绍了硫酸钙晶须的结构形貌特征与形成机理,详细阐述了国内外制备硫酸钙晶须的方法,介绍了常压酸化法、水热合成法、离子交换法、微乳液法等制备工艺的研究进展,分析了不同制备方法的优缺点;同时介绍了硫酸钙晶须在材料改性、环境保护等领域的应用.对深入研究硫酸钙晶须制备及作用机理具有的重要意义,为硫酸钙晶须未来应用以及矿产资源综合回收利用提供了科学性指导.      

被盖层分隔储层油源断裂输导油气有效时期厘定方法及其应用

为了准确研究含油气盆地被盖层分隔储层油源断裂在油气成藏中的作用,在被盖层分隔储层油源断裂输导油气机理及有效时期研究的基础上,通过断裂停止活动时期、断裂开始破坏泥岩盖层封闭能力时期和断裂填充物开始封闭时期确定出油源断裂输导油气时期,利用源岩地化特征确定出源岩排烃时期,将二者叠合建立了一套被盖层分隔储层油源断裂输导油气有效时期的厘定方法。应用结果表明:在测线L2处F1油源断裂向东一段储层输导油气有效时期相对较长,为5.3 Ma,较有利于油气在东一段储层中运聚成藏（目前构造高部位尚未钻探）;在测线L8处F1油源断裂向东一段储层输导油气有效时期相对较短,为2.4 Ma,且主要为断裂填充物输导油气,不利于油气在东一段储层中大规模运聚成藏,和F1油源断裂在测线L8附近东一段虽已发现油气,但规模有限一致。该方法可有效用于厘定被盖层分隔储层油源断裂输导油气有效时期。      

钢铁工业废水除盐技术与展望

概述了钢铁工业废水处理中除盐技术的目的和意义,分类介绍了膜法和电吸附两种常见除盐技术的原理及在钢铁废水处理中的应用。最后,提出了钢铁废水除盐技术发展的一些展望。     

Determination of potential migrants present in Nylon 'microwave and roasting bags' and migration into olive oil

Two groups of potential migrants were found in Nylon "microwave and roasting bags' (MRBs): volatile compounds were released at cooking temperatures and non-volatile compounds were extracted with methanol and/or water. A dynamic headspace system at 200 degrees C followed by gas chromatography (GC) coupled to mass spectrometry (MS) was used for determination of volatile compounds. Cyclopentanone (31.7 mg/bag), 2-cyclopentyl cyclopentanone (17.4 mg/bag), hexadecane (2.6 micrograms/bag), heptadecane (3.2 micrograms/bag), octadecane (3.0 micrograms/bag) and epsilon-caprolactam (5.0-35.5 mg/ bag) were the main volatile compounds present in the MRBs. High performance liquid chromatography (HPLC) and mass spectrometry were combined for identification and quantification of non-volatile compounds extracted with methanol (46.0 mg/bag). Nylon 6,6 cyclic monomer and cyclic oligomers up to the tetramer and Nylon 6 monomer and cyclic oligomers up to the octamer were identified and quantified, confirming that the plastic was made of Nylon 6,6 and Nylon 6 polymers. The same non-volatile compounds (except Nylon 6 heptamer and octamer) were found to migrate into olive oil at 175 degrees C for 1 h. A total of 0.916 mg/dm2 (19.2 mg/bag) of non-volatile compounds migrated into olive oil (41.8% of those quantified in the plastic material).     

Effects of dietary corn and olive oil versus coconut fat on biliary cholesterol secretion in rats

We have studied the effects of dietary corn and olive oil versus coconut fat on bile formation and fluidity of hepatic plasma membranes in rats. After 4 weeks of feeding the purified diets containing 9% (w/w) of the test fats, there was no difference in plasma cholesterol concentration between the dietary groups. The amount of free and esterified cholesterol in the liver was significantly higher in rats fed either corn oil or olive oil as compared with coconut fat. In the rats fed olive oil, but not in those fed corn oil this was associated with lower rates of biliary phospholipid excretion. Bile flow was not differently influenced by the three dietary fats. Hepatic plasma membranes of the rats fed corn or olive oil contained more cholesterol and less phospholipids than those on coconut fat, which was, however, not accompanied by changes in fluidity of the membranes. These results indicate that in rats the type of dietary fat can induce considerable changes in hepatic cholesterol metabolism without affecting plasma cholesterol concentrations, and without consistent effects on biliary cholesterol secretion.