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Human intestinal Caco-2 cell model to evaluate the absorption of 7-ketophytosterols and their effects on cholesterol transport

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Food Science and Human Wellness 2023年第5期12卷 1701-1707页

作者： Mengmeng Wang Min Yu Amel Thanina Amrouche Fan Jie Shengyang Ji Baiyi Lu National Engineering Laboratory of Intelligent Food Technology and Equipment Key Laboratory for Agro-Products Postharvest Handling of Ministry of Agriculture and Rural AffairsKey Laboratory for Agro-Products Nutritional Evaluation of Ministry of Agriculture and Rural AffairsZhejiang Key Laboratory for Agro-Food ProcessingFuli Institute of Food ScienceCollege of Biosystems Engineering and Food ScienceZhejiang UniversityHangzhou 310058China Pharmaceutical Informatics institute College of Pharmaceutical SciencesZhejiang UniversityHangzhou 310058China

7-Ketophytosterols are the major oxidation products of phytosterols in foods, which have been associated with atherosclerosis. However, their absorption mechanism remains unclear. The aim of our work was to investigate the absorption mechanism of 7-ketophytosterols and their effects on the cholesterol transport using Caco-2 cell model. The absorption percentage of 7-ketositosterol and 7-ketocampesterol was 1.16%-1.68% and 1.18%-2.23% respectively in the Caco-2 model, which is higher than that of their parent phytosterols, but lower than cholesterol-d7. The apparent permeability of 7-ketositosterol and 7-ketocampesterol at 30 μmol/L in the basolateral(BL)-to-apical(AP)direction were 0.42-and 0.55-fold of that in the AP-to-BL direction, indicating an active intake in the permeation mechanism of 7-ketophytosterols. Ezetimibe could significantly inhibit the transport of 7-ketophytosterols(P < 0.05), which means that their transport depends on niemann-pick c1-like 1(NPC1L1)protein. The transport of cholesterol-d7 was significantly inhibited by 7-ketophytosterols(P < 0.05). Taken together, this study deepened our understanding of the absorption mechanism of common food-born 7-ketophytosterols and provides useful information on the inhibition of 7-ketophytosterols absorption.

关键词： 7-Ketophytosterols Absorption mechanism Cholesterol absorption Niemann-pick c1-like 1

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Alumina Supported Vanadium Oxide Catalysts for Residue Hydrotreating

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China Petroleum processing & Petrochemical Technology 2013年第1期15卷 1-9页

作者： Jia Yanzi Li Dingjianyi Yang Qinghe Li Dadong Sun Shuling Nie Hong Research institute of Petroleum processing SINOPEC

In order to evaluate the role of vanadium in the hydrogenation (HYD) reaction, a series of alumina supported vanadium catalysts were prepared and characterized by SEM, XRD, Raman spectrometry, 51V NMR, XPS, as well as TPR analyses. The catalytic performance of vanadium in HYD of model molecules (naphthalene) and real feedstock (Kuwait atmospheric residue) was studied after sulfidation of the catalysts. It can be concluded that the HYD capabilities of V/Al2O3 catalysts are lower than that of conventional NiMo/Al2O3 catalyst (RefNiMo). The V/Al2O3 catalysts can only facilitate hydrogenation of the first ring of naphthalene, but have little effect on the further hydrogenation of tetralin. Owing to the different forms of metals and sulfur compounds in residue, the weak HYD activity of V/Al2O3 catalysts is able to facilitate the HDM reaction of the residue, albeit with a slight effect on HDS activity.

关键词： residue vanadium hydrodemetallization hydrodesulfurization

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The Form of Sulfate in Pseudo-Boehmite and Its Effect on Properties of Pseudo-Boehmite

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China Petroleum processing & Petrochemical Technology 2014年第4期16卷 1-6页

作者： Zou Sumeng Yang Qinghe Zeng Shuangqin Nie Hong SINOPEC Research institute of Petroleum processing

A series of pseudo-boehmite samples with their sulfate radicals(SO2-4) concentration ranging from 0.9% to 3.0% were prepared by the reaction of Na Al O2 solution on Al2(SO4)3 solution. The existing form of sulfate radicals was investigated. Results have shown that sulfates in pseudo-boehmite included two parts, the soluble sulfate radicals and the insoluble sulfate radicals, which accounted for 99% of the total amount of sulfate radicals. XRD, low-temperature N2-adsorption, and TEM were used to characterize the properties of these pseudo-boehmite samples. Results have shown that the relative crystallinity and crystal size of pseudo-boehmite decreased with the increase of sulfate radicals in the support. In the meanwhile, the bound water content in pseudo-boehmite increased. The TEM images of pseudo-boehmite indicated that the pseudoboehmite was prone to become amorphous hydrated alumina. However, the effect of sulfate content on the specific surface area and pore structure of aluminium oxide was insignificant.

关键词： NaAlO2-Al2(SO4)3 sulfate pseudo-boehmite alumina surface properties

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Influence of Different Hydrocarbon Molecules on Physical Properties of Mineral Base Oils

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China Petroleum processing & Petrochemical Technology 2017年第1期19卷 33-45页

作者： Wang Weijun Long Jun He Yifeng Sun Hongwei Tian Songbai Zheng Hui SINOPEC Research institute of Petroleum processing

Different kinds of base oils with different viscosity were analyzed in this paper, including eight mineral base oils, alkylnaphthalene and three synthetic PAO oils. The influence of different hydrocarbon molecules on physical properties of mineral base oils was investigated, such as density(d), kinematic viscosity(KV), viscosity index(VI), etc. Possible reasons for some inconsistent phenomena in data processing were also theoretically analyzed in detail. The refractive indexes(RI), d and molecular weight(M) decrease linearly with the increase of paraffinic content other than KV, which declines exponentially. There are no clear relationships between physical properties of base oils and naphthenic content while polycyclic alkanes show a strong correlation with M and KV. The influence of aromatics on physical properties of base oils is just the opposite of paraffin's. VI of the base oils with low aromatics content increases linearly as their paraffinic contents rise when their carbon numbers are approximately equal. However, base oils with high aromatics content follow an utterly different rule, in which VI declines dramatically linearly with the increase in polycyclic aromatic content, which is the essential reason why naphthenic base oils all have terrible viscosity-temperature characteristics while paraffinic base oils usually do not.

关键词： base oil hydrocarbon molecule physical property

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Synthesis of Polymethacrylates Used as Multifunctional Lubricating Oil Additives

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China Petroleum processing & Petrochemical Technology 2015年第2期17卷 69-75页

作者： Liu Yinong Fan Lichuang Duan Qinghua SINOPEC Research institute of Petroleum processing

In this paper, four kinds of polymethacrylates(PMAs) used as multifunctional additives were synthesized from quaternary C1—C14 methacrylate, among which sample 4 exhibited relatively better performance. According to the methacrylate ratio of sample 4, the optimized reaction conditions of PMA were explored by orthogonal experiments comprising 4 factors and 3 levels, and the optimized reaction conditions covered an initiator dosage of 0.8 %, a molecular weight regulator dosage of 0.4%, a reaction temperature of 95 ℃ and a reaction time of 8.5 h. When the optimized PMA samples were used to formulate the 75W/90 automotive gear base oil, they exhibited improved shear stability and good low temperature property. In comparison with foreign commercial polymethacrylate GP, the optimized PMA samples exhibited better thickening ability, similar shear stability and slightly weak low temperature property, with their performance being the same as GP's on the whole. The slight difference in the performance between the optimized PMA and GP was attributed to the difference of chain length of copolymers and the distribution of relative molecular mass between them.

关键词： polymethacrylate thickening ability shear stability low temperature property

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Study on Tribology Performance of Different Lubricant Additives under Atmospheric Pressure and High Vacuum Conditions

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China Petroleum processing & Petrochemical Technology 2016年第4期18卷 81-91页

作者： Peng Qian Huang Zhiyang Yang He Song Haiqing Zhang Jianrong Research institute of Petroleum processing SINOPEC

By using PAO-10 as the base oil, the tribological behavior of 11 additives under high vacuum condition was evaluated. By adopting some surface analytical instruments, such as scanning electron microscopy(SEM), energy dispersive spectroscopy(EDS) and X-ray photoelectron spectroscopy(XPS), the tribological mechanisms of these additives were studied. In air, O_2 can react with metal to form metal oxide that can protect the surfaces of rubbing pair during the tribological tests. According to the theory of the competitive adsorption, the function of some active elements is weakened. In a vacuum environment, the additives contributed more to the lubrication performance. The sulfur-containing additives could react with Fe to produce Fe Sx and "M—C" bonds("M" represents metal). They both had contributions to the lubrication. As for the phosphorus-containing additives, they only generated the phosphates during the tests. When the sulfur and phosphorus-containing additives were applied, the generated phosphates and Fe Sx had the primary contribution to the lubrication performance during the tests.

关键词： anti-wear additive high vacuum lubrication mechanism anti-wear properties friction reducing properties

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Synergetic Effect of Y Zeolite and ZSM-5 Zeolite Ratios on Cracking, Oligomerization and Hydrogen Transfer Reactions

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China Petroleum processing & Petrochemical Technology 2014年第3期16卷 1-9页

作者： Gong Jianhong Xu Youhao Long Jun Wei Xiaoli SINOPEC Research institute of Petroleum processing

The objective of this study is to explore the optimum composition of Y and ZSM-5 zeolites to develop novel catalysts for obtaining lower gasoline olefins content and higher propylene yield. Five composite zeolite catalysts with varying Y zeolite/ZSM-5 zeolite ratios have been prepared in this work to investigate the synergy between the Y zeolite and ZSM-5 zeolite on the selectivity to protolytic cracking, β-scission, oligomerization, and hydrogen transfer reactions using a FCC naphtha feedstock at 480 ℃ in a confined fluidized bed reactor. Experimental results showed that the composite catalyst with a Y zeolite/ZSM-5 zeolite ratio of 1:4 had the highest protolytic cracking and β-scission ability, which was even higher than that of pure ZSM-5 catalyst. On the other hand, the catalyst with a Y zeolite/ZSM-5 zeolite ratio of 3:2 exhibited the strongest hydrogen transfer functionality while the pure Y zeolite based catalyst had the highest oligomerization ability. For all the catalysts tested, increasing conversion enhanced the selectivity to protolytic cracking and hydrogen transfer reactions but reduced the selectivity to β-scission reaction. However, no clear trend was identified for the selectivity to oligomerization when an increased conversion was experienced.

关键词： composite zeolites protolytic cracking β-scission oligomerization hydrogen transfer

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Molecular Characterization of Hydrotreated Atmospheric Residue Derived from Arabian Heavy Crude by GC FI/FD TOF MS and APPI FT-ICR MS

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China Petroleum processing & Petrochemical Technology 2012年第4期14卷 80-88页

作者： Diao Rui Wang Wei Wang Naixin Liu Zelong Dai Lishun Tian Songbai Research institute of Petroleum processing SINOPEC

High resolution mass spectrometry in combination with distillation and SARA fractionation provides us an opportunity for in-depth understanding about the hydrotreating process at the molecular level. In this study, the atmospheric residue derived from Arabian heavy crude and its hydrotreated products were initially subjected to distillation and SARA fractionation. The saturates were characterized by GC FI/FD TOF MS. The aromatics and resins were characterized by APPI FT-ICR MS. Compositional changes of different compounds (paraffins, naphthenes, aromatic hydrocarbons, and heteroatomic compounds) contained in different distillates (vacuum gas oil, vacuum residue) were obtained. More detailed knowledge about the hydrotreating process was achieved.

关键词： hydrotreating petroleum residue FT-ICR MS GC FI/FD TOF MS

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The Influence of Feeding Method on Fluidization Behavior of Fixed Fluidized Bed

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China Petroleum processing & Petrochemical Technology 2014年第1期16卷 13-18页

作者： Ren Shihong Mao Anguo Wei Xiaoli SINOPEC Research institute of Petroleum processing

An experimental installation of cold model simulation was set up to study the bed pressure drop in different regions of fixed fluidized bed reactor during top feeding and bottom feeding, respectively, at various gas velocities with the fluidization image of solid particles monitored at the same time. By comparing the changes in bed density and operating gas velocity in different regions of fixed fluidized bed reactor, the influence of top feeding and bottom feeding patterns on fluidization behavior could be investigated. The results showed that the bed density in top feeding reactor responded more stably to the change in gas velocity along with the advantage of working in a wider range of operating gas velocities. Based on this study, it is concluded that existing bottom feeding reactor configurations cannot meet the fluidization requirements; and optimization of bottom feeding reactor will be needed.

关键词： feeding method fixed fluidized bed fluidization behavior bed density operating gas velocity

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Preparation of Overbased Calcium Alkylbenzene Sulfonate for Formulating Complex Sulfonate Grease

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China Petroleum processing & Petrochemical Technology 2015年第1期17卷 89-95页

作者： Liu Yinong SINOPEC Research institute of Petroleum processing

Six kinds of alkylbenzene sulfonic acids were selected to prepare the sulfonates S1—S6. Among them, the sulfonates S3, S4, and S6 could be incorporated into lubricating grease with good performance in comparison with the grease produced from commercial sulfonates T106-1 and T106-2. The optimized conditions for synthesis of the sulfonates S3, S4, and S6 were explored by using different mass ratios of methanol, water and the type of copromoters. It was found out that the appropriate conditions for synthesis of the sulfonate S3 included a methanol to M(M is the total mass of alkylbenzene sulfonic acid and base oil) mass ratio of 16%, a water to M mass ratio of 4%, and a copromoter A to M mass ratio of 2%; the appropriate conditions for synthesis of the sulfonate S4 included a methanol to M mass ratio of 24%, a water to M mass ratio of 2%, a copromoter B to M mass ratio of 2%; and the optimized conditions for synthesis of the sulfonate S6 included a methanol/ M mass ratio of 8%, a water/M mass ratio of 4% and a copromoter B/M mass ratio of 2%. The new sulfonates S3, S4, and S6 produced under the optimized conditions exhibited higher TBN and better antiwear property in camparison with the previous products. Grease samples G9, G10, and G11 were prepared with new sulfonates S3, S4, and S6 successfully and exhibited improved water stability and high temperature performance.

关键词： complex sulfonate grease overbased calcium sulfonate optimization

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