Characterization of Astaxanthin Nanoemulsions Produced by Intense Fluid Shear through a Self-Throttling Nanometer Range Annular Orifice Valve-Based High-Pressure Homogenizer

Stable, oil-in-water nanoemulsions containing astaxanthin (AsX) were produced by intense fluid shear forces resulting from pumping a coarse reagent emulsion through a self-throttling annular gap valve at 300 MPa. Compared to crude emulsions prepared by conventional homogenization, a size reduction of over two orders of magnitude was observed for AsX-encapsulated oil droplets following just one pass through the annular valve. In krill oil formulations, the mean hydrodynamic diameter of lipid particles was reduced to 60 nm after only two passes through the valve and reached a minimal size of 24 nm after eight passes. Repeated processing of samples through the valve progressively decreased lipid particle size, with an inflection in the rate of particle size reduction generally observed after 2–4 passes. Krill- and argan oil-based nanoemulsions were produced using an Ultra Shear Technology™ (UST™) approach and characterized in terms of their small particle size, low polydispersity, and stability.     

Capillary electromigration methods for fatty acids determination in vegetable and marine oils: A review

Fatty acids determination is of paramount importance for quality control and suitable labeling of edible oils, required by regulatory agencies in several countries, and fast methods for this determination are worldly desired. This review article aimed to explore the available analytical methods for vegetable and marine oils analyses employing CE, which can be a straightforward and faster alternative than GC methods for fatty acid determination, considering some purposes. CE usually offers the possibility of a rapid analysis with a simple preparation of the sample, without requiring specific columns, which are inherent advantages of the technique. Instrumental conditions and the key points about fatty acids determination employing the technique are highlighted, and the main challenges and perspectives are also approached. Potential use of CE for edible oil analyses has been demonstrated for research and routine, which can be of interest for industries, regulatory agencies, and edible oil researchers. Therefore, we have explored the analytical approaches described in the last decades, intending to spread the interest of CE methods for fatty acid monitoring, label accuracy assessment, and food authenticity evaluation of edible oils.     

Modified soybean oil as a reactive diluent: Synthesis and characterization

Soybean oil was modified in two steps: (1) conjugation of soybean oil and (2) Diels‐Alder addition with 3‐(trimethoxysilyl)propyl methacrylate, 2,2,2‐trifluoroethyl methacrylate and triallyl ether acrylate. The structures were characterized using ¹H NMR, ¹³C NMR, ¹³C‐¹H gradient heteronuclear single quantum coherence (gHSQC) NMR spectroscopy, and MALDI‐TOF mass spectrometry. The ¹³C‐¹H gHSQC NMR spectra helped confirm the formation of a cyclohexene ring in all reactions, indicating a Diels‐Alder addition. The diluent efficiency of modified soybean oil was evaluated in long oil alkyd formulation. Triallyl ether functionalized soybean oil resulted in the highest reduction in the viscosity of the alkyd formulations. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52, 3045–3059     

Ultrasonic emulsification of eucalyptus oil nanoemulsion: Antibacterial activity against Staphylococcus aureus and wound healing activity in Wistar rats

The plant derived essential oil nanoemulsion was prepared using a mixture of components containing eucalyptus oil as organic phase, water as continuous phase, and non ionic surfactant, Tween 80, as emulsifier at a particular proportion of 1:1 v/v%. The ultrasonication was applied for varied processing time from 0 to 30 min to study the effect of time on the formation of nanoemulsion and physical stability of formulation by this method. The transparency and stability of emulsion was enhanced when the sonication time was increased compared to hand blender emulsion. The most stable nanoemulsion was obtained in 30 min sonication having the mean droplet diameter of 3.8 nm. The antibacterial studies of nanoemulsion against Staphylococcus aureus by time kill analysis showed complete loss of viability within 15 min of interaction. Observations from scanning electron microscopy of treated bacterial cells confirmed the membrane damage compared to control bacteria. Furthermore, the wound healing potential and skin irritation activity of the formulated nanoemulsion in Wistar rats, suggested non-irritant and higher wound contraction rate with respect to control and neomycin treated rats. These results proposed that the formulated system could be favourable for topical application in pharmaceutical industries.     

Multispectroscopic Characterization of Oil on Copper Painting

A small plate of oil on copper painting from the Italian Renaissance period was characterized by means of noninvasive spectroscopic methods. The study was conducted by the use of energy-dispersive X-ray fluorescence, X-ray diffraction, and Raman and diffuse reflectance infrared Fourier transform spectroscopies to determine the technology production process in such kinds of artworks. Results allowed us to characterize the copper alloy of the support media; the preparation layer, which is composed by white lead; and the pictorial layer of variable composition (green copper sulphate compounds, red lead, carbon black, brown earth pigments, gold, vermilion, and white lead). The complementarity of the techniques used in this study has proven to be highly effective.     

Original diols from sunflower and ricin oils: Synthesis,characterization, and use as polyurethane building blocks

A series of novel fatty acid‐based diols were designed and synthesized from sunflower and ricin oils using optimized chemical reactions and purifications. These diols were categorized in two different types: (i) fatty acid‐based monoester containing diols (FAmE‐1 to FAmE‐6) and (ii) fatty acid‐based diester containing diols (FAdE‐1 to FAdE‐8). Their synthesis involved a series of reactions such as transesterification, epoxidation, ring opening of epoxide, and thiol‐ene additions. Analyses of these new fatty acid‐based diols were performed by HPLC/GC and NMR spectroscopy. The latter were then demonstrated as polyurethane (PU) precursors in the bulk polymerization with isophorone diisocyanate in the presence of dibutyl tin dilaurate as a catalyst. The effects of the diol nature and purity on the PU synthesis and properties were investigated. The structural characterization of the different PUs was carried out by means of FTIR, ¹H NMR, and ¹H DOSY NMR spectroscopy. The thermomechanical and rheological properties of these new PUs were found dependent on the chemical structure and purity of the diol building block. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012     

Multiresidue determination of organochlorines in fish oil by GC-MS: A new strategy in the sample preparation

A rapid, economic and environmentally friendly analytical methodology has been implemented for the determination of α-, β-, γ- and δ-HCH, p,p′-DDT, p,p′-DDD and p,p′-DDE, PCBs congeners #28, #52, #101, #153, #138 and #180 and Hexachlorobenzene in fish oil. 1,2,3,4-Tetrachloronaphtalene was used as internal standard. The sample preparation, consisting of a single step of clean-up and fractionation, took place in a column filled with different layers of neutral and sulphuric acid modified silica. The analytes were eluted by vacuum with of hexane. Significant reduction in terms of solvents, sorbents, and analysis time was achieved in comparison with literature.Gas chromatography coupled to mass spectrometry was used for the separation and determination of the analytes. The instrumental limits of detection were from 0.1 to 1.3 ng mL⁻¹ and the response of the detector was linear up to 200 ng mL⁻¹. The separation proved to be precise (RSD < 3.7% in peak area) and robust in terms of peak area, peak efficacy and resolution. The methodology was validated with two certified reference materials of cod liver oil, BCR 598 and BCR 349, obtaining no statistically significant differences between the concentrations found and certified. For the analytes that were not certified, aliquots of the reference materials were spiked and the recoveries obtained were satisfactory. These results were consistent with those found previously for DDTs by gas chromatography with an electron-capture detector.The methodology was applied to the analysis of three fish oil pills sold in Spain as a dietary supplement of vitamins and omega-3 fatty acids. The sum of the analytes studied was from 64 to 80 ng g⁻¹. The most abundant compounds are PCBs, followed by DDTs in all samples.     

基于近红外光谱的润滑油中含水量T-S模糊辨识

油中含水量近红外光谱具有复杂性、非线性和难以用明确数学模型表达的特点.利用无信息变量消除法提取有效波长,采用模糊C均值聚类算法得出输入空间的划分和聚类中心,结合递推最小二乘法辨识后件参量,建立了润滑油的近红外光谱与含水量的Takagi-Sugeno模糊模型.将该辨识算法与偏振最小二乘法模型进行比较,并对实测数据进行了验证.结果显示:经无信息变量消除法提取34个特征波长建立的Takagi-Sugeno模型能够精确地反映出润滑油光谱数据与含水量的关系,其对验证集样本进行预测的相关系数和均方根误差分别为0.964 6和1.531 2×10-4,获得了满意的预测准确度.实验结果验证了应用光谱技术检测油中含水量的可行性,同时也为油中其他污染物的在线监测提供了新方法.     

The second‐order upwind finite difference fractional steps method for moving boundary value problem of oil‐water percolation

The research of the three‐dimensional (3D) compressible miscible (oil and water) displacement problem with moving boundary values is of great value to the history of oil‐gas transport and accumulation in basin evolution, as well as to the rational evaluation in prospecting and exploiting oil‐gas resources, and numerical simulation of seawater intrusion. The mathematical model can be described as a 3D‐coupled system of nonlinear partial differential equations with moving boundary values. For a generic case of 3D‐bounded region, a kind of second‐order upwind finite difference fractional steps schemes applicable to parallel arithmetic is put forward. Some techniques, such as the change of variables, calculus of variations, and the theory of a priori estimates, are adopted. Optimal order estimates in l² norm are derived for the errors in approximate solutions. The research is important both theoretically and practically for model analysis in the field, for model numerical method and for software development. Thus, the well‐known problem has been solved.Copyright © 2013 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 30: 1103–1129, 2014