bluuebunny/crossref_metadata_2025_split huggingface dataset:
Ultrasonically assisted solid‐phase extraction and GC analysis of filbertone in hazelnut oil
Authors: de Castillo María Luisa Ruiz , Herraiz Marta 
Published: November 2006

AbstractUltrasound was used to assist solid‐phase extraction (SPE) of filbertone (E‐5‐methylhept‐2‐en‐4‐one) from hazelnut oil. Interferences from TG were reduced for effective separation and detection during chromatographic analysis. The enantiomeric distribution of filbertone was determined. Different sorbent materials, sample volumes, and eluents were tested, and the effect on filbertone recovery by ultrasound during the elution step was evaluated. Experimentation performed on a 2‐mL volume of oil diluted with a 2‐mL volume of n‐hexane, using a silica modified with either a cyano or phenyl group during the extraction, and ultrasound‐assisted elution with a 1‐mL volume of chloroform allowed filbertone recoveries of up to 94.4% (relative SD 6.5%) vs. 11% obtained when ultrasound was not applied. This improvement is most likely due to a mechanism of cavitation. Ultrasonically assisted SPE is proposed as an accesible and simple alternative to multidimensional chromatographic techniques to accomplish the reliable determination of the enantiomeric excess of chiral compounds in complex matrices, such as hazelnut oil, since experimental conditions that can bring about racemization are not required.
Sensory evaluation of a nutritional beverage containing canola oil/caprylic acid structured lipid
Authors: Osborn Hannah T. , Shewfelt Robert L. , Akoh Casimir C. 
Published: November 2006

AbstractChocolate‐flavored nutritional beverages were formulated with canola oil and a structured lipid (SL) to determine the effect of the SL on the sensory profile of the beverage. The SL was synthesized from canola oil and caprylic acid in a bioreactor packed with an sn‐1,3‐specific lipase obtained from Rhizomucor miehei. Differences were determined by using a triangle test panel comprising 38 members and a 7‐member trained quantitative descriptive analysis (QDA) panel. Twenty‐three panelists correctly identified the odd sample during the triangle testing, which corresponds to a significant difference (P<0.01). QDA results indicated that substituting the SL for unmodified canola oil significantly enhanced the perception of sweet flavor and decreased bubble formation. All other attributes were unchanged when the SL was substituted for unmodified canola oil in the beverage formulations. This SL may be suitable for use by manufacturers of nutritional beverages who market their products to people on modified diets and patients who are recovering from illness or injury. The new formulation would provide consumers with a source of energy that is more readily metabolized in the body while providing essential FA.
Simulation of multistage extraction of antioxidants from Chilean hazelnut (Gevuina avellana) hulls
Authors: Moure Andrés , Franco Daniel , Sineiro Jorge , Domínguez Herminia , Núñez María José 
Published: November 2006

AbstractThe objective of this study was to analyze the factors affecting the ethanol extraction of Chilean hazelnut (Gevuina avellana) hulls to obtain antioxidant compounds. The effects of temperature on the kinetics of polyphenolics extraction and on the antioxidant activities of the extracts were assessed. The radical‐scavenging activities of the extracts were comparable with that of BHA when used at the same concentration. The optimal temperature for the antioxidant activities of the extracts was 40°C. A four‐stage cross‐flow extraction was carried out and a four‐stage countercurrent extraction was simulated, where each stage lasted 30 min. Best results were obtained with countercurrent extraction, which produced an extract that showed 94.4% α,α‐diphenyl‐β‐picrylhydazyl radical inhibition, compared with 86.2% obtained in the first stage of cross‐flow extraction and 92.62% in a batch extraction that lasted 100 h. UV‐vis and NIR spectra of extracts from cross‐flow and from the simulated countercurrent extraction revealed that the composition of extracts varied along the stages and was affected by the operational strategy.
The study of oxazolidone formation from 9,10‐epoxyoctadecane and phenylisocyanate
Authors: Javni Ivan , Guo Andrew , Petrovic Zoran S. 
Published: November 2006

AbstractThe formation of oxazolidone from 9,10‐epoxyoctadecane and phenylisocyanate was studied. One branch of epoxidized vegetable oil with one epoxy group per chain corresponds to 9,10‐epoxyoctadecane. This model could explain the probability of oxazolidone formation from natural oil‐derived epoxides. Epoxidized natural oils are TG consisting of glycerin and three FA with or without one to three epoxy groups in the middle of the chain. To study oxazolidone formation from an internal epoxy group without possible interference from the side reactions on the ester group, 9,10‐epoxyoctadecane was selected as the most appropriate model compound. Epoxy groups in the middle of allong aliphatic chain are of low reactivity toward isocyanates, and preparation of oxazolidones requires fairly harsh conditions such as high temperatures and catalysts, which also promote side reactions. The dominant side reaction is rearrangement of the epoxy groups. We found that the direction and magnitude of the rearrangement and the yield of any particular product depended on the catalyst used. Lithium chloride, aluminum trichloride, and zinc iodide catalyzed oxazolidone formation, along with the catalysis of side reactions such as ketone and carbonate formation. Aluminum trichloride showed the highest conversion of 9,10‐epoxyoctadecane to oxazolidone. Aluminum triisopropoxide, triphenylantimony iodide, and imidazole did not catalyze the formation of oxazolidone. They were effective as catalysts of epoxy group rearrangement and promoted the formation of hydroxyl, ketone, and carbonate compounds. Hydroxyl groups reacted with isocyanate to produce urethane.
Efficient esterification of sorbitan oleate by lipase in a solvent‐free system
Authors: Xu Yan , Wang Dong , Mu Xiao Qing , Ni Yong Quan 
Published: November 2006

AbstractThe lipase‐catalyzed esterification of sorbitan with oleic acid in a solvent‐free system to form sorbitan oleate (commercial name Span80) was studied as a feasible approach aimed at meeting the demand for sugar alcohol‐based surfactants. Screened results obtained from enzymatic synthesis of sorbitan oleate indicated that Novozym 435 had its highest catalytic activity in a solvent‐free system. The introduction of a reduced‐pressure system increased the production of sorbitan oleate to a maximum of 95% of theoretical, obtained from 0.2 mol sorbitan, 0.1 mol oleic acid, and 2.0 g lipase (6 wt% of sorbitan) in a solvent‐free reaction mixture at optimal reaction conditions. Results obtained from lipase‐catalyzed batch esterification reactions showed that more than 90% conversion of sorbitan oleate was maintained after 10 batches of esterification reactions, indicating excellent enzyme stability. Subsequent analysis by HPLC indicated that the product of enzyme‐catalyzed esterification by the immobilized lipase contained a significantly greater amount of monoester (about 80%) compared to the composition obtained by chemical synthesis (about 50%).
Roasting effects on the distribution of tocopherols and phospholipids within each structural part and section of soybeans
Authors: Yoshida Hiromi , Matsuda Kyoko , Hirakawa Yuki , Mizushina Yoshiyuki 
Published: November 2006

AbstractTo clarify the effects of microwave roasting on the distribution of tocopherols and FA of phospholipids within soybeans, whole soybeans (Glycine max) were treated by microwave and further evaluted as compared to a raw sample. Tocopherol homologs, measured using HPLC, and phospholipid profiles, quantified with GC, were determined in the seed coat, the embryonic axis, and selections of cotyledons separated from three cultivars. The tocopherols were predominantly detected in the axis, followed by the cotyledons, and then very little in the coat. As much as 25% of the individual tocopherols originally present in the coat were lost at 12 min of roasting, whereas <25% was lost in the cotyledons and the axis after 20 min of roasting. The greatest rate of phospholipid loss (P<0.05) was observed in PE, followed by PC and PI, and their changing patterns were more pronounced in the coat than in the cotyledons or the axis. Thus, tocopherol content and phospholipid profiles change with microwave roasting according to tissue.
The antioxidant effect of natural substances on lipids during irradiation of chicken legs
Authors: Mahrour A. , Caillet S. , Nketsia‐Tabiri J. , Lacroix M. 
Published: November 2006

AbstractEntire fresh chicken legs were subjected to three pretreatments (packaged in air; packaged under vacuum; or marinated in natural plant extracts and packaged in air) followed by irradiation (0, 3, or 5 kGy). The control and irradiated chicken legs were stored at 4°C and analyzed for FA composition and sensory quality at predetermined intervals. Irradiation dose had a significant (P<‐0.01) effect on FA derived from phospholipid but less than on FA derived from a neutral lipid. In general, levels of unsaturated FA decreased as the radiation dose increased; however, for marinated chicken legs irradiated with 5 kGy, levels of linoleic acid (C18∶2) and arachidonic acid (C20∶4) derived from the phospholipid fraction were significanlty (P≤0.05) higher than those irradiated in air or under vacuum. The concentration of FA also decreased significantly (P≤0.05) as storage time increased. For chicken legs packaged in air or marinated and then packaged in air, significant (P≤0.01) inverse correlations existed between high‐carbon‐number PUFA and lower‐carbon‐number (≤17) saturated FA; this relationship was not apparent in samples irradiated under vacuum. A processing combination of marinating and vacuum packaging might better control lipid oxidation and degradation in irradiated chicken. Panelists found no significant difference (P>0.05) in the flavor and oder intensity of cooked irradiated chicken legs and their nonirradiated equivalents.
Friction properties of vegetable oils
Authors: Biresaw G. , Adhvaryu A. , Erhan S. Z. 
Published: November 2006

AbstractVegetable oils are a renewable and an environmentally friendly alternative to petroleum‐based oils in lubrication and other important application areas. Vegetable oils fall into two broad chemical categories: triesters (or TG) and monoesters. Most vegetable oils are triesters of glycerol with FA, whose characteristics are dependent on the chemistry and composition of the FA residues. A small percentage of vegetable oils are monoesters of long‐chain FA and fatty alcohols of varying chemistries. In this work, the free energy of adsorption (ΔGads) of safflower (SA), high‐oleic safflower (HOSA), and jojoba (JO), methyl oleate (MO), and methyl palmitate (MP) on steel were investigated. SA and HOSA are TG of vegetable oils with FA residues of radically different degrees of unsaturation. JO is a monoester vegetable oil. ΔGads is one of the major factors affecting the boundary friction properties of lubricant ingredients. ΔGads was found to increase in the order: HOSA≤SA<JO<MO≤MP. The results are consistent with the degree of functionality and other chemical properties of the oils studied.
Characterization of sacha inchi (Plukenetia volubilis L.) oil by FTIR spectroscopy and 1H NMR. Comparison with linseed oil
Authors: Guillén María D. , Ruiz Ainhoa , Cabo Nerea , Chirinos Rosana , Pascual Gloria 
Published: November 2006

AbstractThree oil samples obtained from sacha inchi (Plukenetia volubilis L.) seeds were studied by means of FTIR and 1H NMR. Frequency data of the most significant bands of the IR spectrum of this oil are given. These data show that sacha inchi oil has a high degree of unsaturation. The same fact is deduced from the ratio between the absorbance of the bands due to the stretching vibrations of the cis olefinic CH double bonds at 3010.5 cm−1 and to the methylene symmetrical stretching vibrations at 2855.1 cm−1. The proportions of monounsaturated, polyunsaturated, and saturated acyl groups were predicted from the frequency of some IR bands, and these were in satisfactory agreement with the values obtained through FAME generation and their quantification by GC. Likewise, simple observation of the 1H NMR spectra provided a great deal of information about sacha inchi oil, with regard not only to the relative proportions of the different acyl groups but also to their nature. Thus, the presence of γ‐linolenic acyl groups was discounted. Furthermore, the area of some 1H NMR signals was used to determine the proportion of saturated and mono‐, di‐, and triunsaturated acyl groups, which also were in satisfactory agreement with the values obtained by classical methods. IR and 1H NMR determinations take very little time in comparison with classical methods and do not require chemical manipulation or transformation of the sample. A comparison was also made between the compositions of sacha inchi and linseed oil. Both oils are important sources of the healthful n−3 linolenic acyl groups, and sacha inchi also contains high proportions of the n−6 linoleic acyl groups.
Side‐chain autoxidation of stigmasterol and analysis of a mixture of phytosterol oxidation products by chromatographic and spectroscopic methods
Authors: Johnsson Lars , Andersson Rolf E. , Dutta Paresh C. 
Published: November 2006

AbstractAlthough the structure of phytosterols is closely related to cholesterol, there is a gap in knowledge concerning the formation and occurrence of oxidation products from phytosterols. The main objective of this study was to isolate and characterize some side‐chain oxidation products formed after autoxidation of stigmasterol. Another objective was to highlight the difficulties in the analysis of phytosterol and a mixture of their oxidation products by GC. Pure stigmasterol was oxidized at 120°C for 72 h in an air‐ventilated oven. Preparative TLC separated the oxidation products, and the products were characterized with GC‐MS and NMR. In addition to the common ring‐structure oxidation compounds, three semipolar oxidation products—24‐ethylcholest‐5,22‐dien‐3β,25‐diol, 24‐ethylcholest‐5,22‐dien‐3β,24‐diol, and 24‐ethyl‐5,22‐choladien‐3β‐ol‐24‐one—were characterized for the first time by TLC, GC‐MS, and NMR. Moreover, the results of the analysis of a large number of oxidation products from sitosterol, campesterol, and stigmasterol by capillary column GC indicated that further efforts and optimization are required in this area.
Trans FA in sunflower oil at different steps of refining
Authors: Tasan Murat , Demirci Mehmet 
Published: November 2006

AbstractThe contents of total trans FA of sunflower oils at different stages of refining processes were determined by capillary GLC. The contents of 18∶1, 18∶2, and 18∶3 trans acids were 0.22±0.03, 2.31±0.23, and 0.03±0.01%, respectively, in physically refined sunflower oils, and 0.05±0.01, 0.69±0.26, and 0.02±0.01%, respectively, in chemically refined sunflower oils. The total trans FA contents drastically increased at the end of the physical refining process. The total trans FA contents of chemically refined sunflower oils were <1%. Because of the high temperature applied in the last stage of physical refining, the content of total trans FA was higher than in chemically refined sunflower oils. The last‐stage conditions should be carefully evaluated to reduce the formation of trans FA during physical refining.
CLA production from ricinoleic acid by lactic acid bacteria
Authors: Ando Akinori , Ogawa Jun , Kishino Shigenobu , Shimizu Sakayu 
Published: November 2006

AbstractThe ability to produce CLA from ricinoleic acid is widely distributed in lactic acid bacteria. Washed cells of Lactobacillus plantarum JCM 1551 were selected as a potential catalyst for CLA production from ricinoleic acid. Cells cultivated in medium supplemented with a mixture of α‐linolenic acid and linoleic acid showed enhanced CLA productivity. Under optimal reaction conditions, with the free acid form of ricinoleic acid as the substrate and washed cells of L. plantarum as the catalyst, 2.4 mg/mL CLA was produced from 3.4 mg/mL ricinoleic acid in 90 h, with a molar yield with respect to ricinoleic acid of 71%. The CLA produced, which was obtained in the FFA form, consisted of a mixture of two CLA isomers, cis‐9,trans‐11‐octadecadienoic acid (21% of total CLA) and trans‐9,trans‐11‐octadecadienoic acid (79% of total CLA), and accounted for 72% of the total FA obtained.
Production of MAG of CLA in a solvent‐free system at low temperature with Candida rugosa lipase
Authors: Watanabe Yomi , Yamauchi‐Sato Yoshie , Nagao Toshihiro , Yamamoto Takaya , Tsutsumi Kentaro , Sugihara Akio , Shimada Yuji 
Published: November 2006

AbstractWe attempted to produce MAG of CLA through lipase‐catalyzed esterification of a FFA mixture containing CLA (referred to as FFA‐CLA) with glycerol. Screening of lipases showed that MAG‐CLA was produced efficiently at 5°C with Penicillium camembertii, Rhizopus oryzae, and Candida rugosa lipases. Among them, C. rugosa lipase was selected because the lipase is widely used as a catalyst for oils and fats processing. The reaction was conducted with agitation of a 300‐g mixture of FFA‐CLA/glycerol (1∶5, mol/mol), a 200‐U/g mixture of C. rugosa lipase, and 2% water. When the reaction was conducted at 30°C, the esterification scarcely proceeded, owing to inhibition of the reaction by glycerol. But the reaction at 5°C eliminated the inhibition and produced MAG efficiently: The degree of esterification reached 93.8% after 58 h, and MAG content in the reaction mixture was 88.4 wt%. To reduce the reaction time, the reactor was connected with a vacuum pump after 24 h, and the reaction was continued with dehydration at 5 mm Hg. The degree of esterification reached 94.7% after 24 h of dehydration (48 h in total), and MAG content increased to 93.0 wt%. Candida rugosa lipase acted a little more strongly on cis‐9, trans‐11 CLA than on trans‐10,cis‐12 CLA, but the contents of the two isomers in MAG obtained from a 48‐h reaction were the same as the contents in FFA‐CLA.
Concentrating PUFA from mackerel processing waste
Authors: Zuta Charles P. , Simpson Ben K. , Chan Hing Man , Phillips Leroy 
Published: November 2006

AbstractMackerel processing waste comprising skins, viscera, and muscle tissue was evaluated for concentrating PUFA by urea complexation. Fish oil was extracted using either chloroform/methanol (2∶1, vol/vol) or hexane/isopropanol (3∶2, vol/vol). The yield of oil, as well as iodine, peroxide, and acid values, was determined for fresh fish oil extracts, and oil samples were storel at −70°C in the presence of 100 ppm α‐tocopherol. PUFA concentrates were prepared from saponified fish oil. The mean oil yields were 9.18±2.3, 9.2%±2.4, and 38.1±3% for viscera, muscle, and skin, respectively. The mean baseline iodine value was 134±5, which increased to 296±7 after urea complexation. It was possible to concentrate PUFA from mackerel processing waste. The type of tissue used did not affect the amount of PUFA concentrated. Mackerel skin was most desirable because of its high oil content.
Development of a flow injection chemiluminescent assay for the quantification of lipid hydroperoxides
Authors: Bunting John P. , Gray David A. 
Published: November 2006

AbstractAn automated flow injection chemiluminescence (FICL) system for measuring lipid hydroperoxide (LOOH) concentrations in oils was developed. Initially, a crude oil‐in‐water emulsion (formed by mixing solvent‐diluted oil with the aqueous‐based CL compound, luminol, and the catalyst for the reaction, cytochrome c) was tested. The assay was rapid (60 samples per hour), reproducible (CV no greater than 10%,n=3) and had a low sample requirement (1 mg of oil) because of its high sensitivity (0.5 nmol LOOH). CL intensity was influenced by the amount and type of oil under analysis. Owing to these factors, quantitative data were attainable only with a uniform oil concentration and with a calibrant derived from an oil equivalent to that under analysis. This method yielded quantitative data in good agreement with an iodometric titration assay for LOOH (r=0.9204). A refinement of the first method consisted of replacing the luminol and cytochrome c CL compounds with lucigenin, resulting in an assay insensitive to α‐tocopherol. A monophasic reaction solution was devised to remove the effect of turbidity; however, the CL signal was still influenced by oil type. Therefore, quantitative data were still attainable only when the same type of oil was used for calibration.
Synthesis of 1,3‐dicapryloyl‐2‐docosahexaenoylglycerol by a combination of nonselective and sn‐1,3‐selective lipase reactions
Authors: Negishi Satoshi , Arai Yuri , Arimoto Shin , Tsuchiya Kinya , Takahashi Isamu 
Published: November 2006

AbstractA two‐step consecutive synthetic method for the production of symmetrical, structured lipids by a combination of nonselective and sn‐1,3 regioselective ester exchange reactions was investigated. In the first step, TAG with unspecifically substituted DHA were obtained by reacting tricapryloylglycerol (CCC) with ethyl docosahexanoate (EtDHA) using the lipase QLM (from Alcaligenes sp.), followed by removing the ethyl ester and CCC by molecular distillation. In the second step, sn‐1,3 regioselective ester exchange was achieved by reacting the resulting TAG with ethyl caprylate (EtC) using the immobilized lipase Novozyme 435 (Candida antarctica lipase), followed by distillation of the ethyl ester and CCC to give sn‐1,3‐dicapryloyl‐sn‐2‐docosahexaenoylglycerol (CDC). The acylglycerol composition of CDC was analyzed by GLC, which showed that the content of dicapryloyl‐docosahexaenoylglycerols (2CD) in the product was 76.4%, and that the ratio of CDC to sn‐1,2‐dicapryloyl‐sn‐3‐docosahexaenoylglycerol contained in 2CD was 82.7∶17.3 (%). The distillates CCC, EtDHA, and EtC could be recycled repeatedly to produce CDC as the substrate for the consecutive ester exchange reaction. In addition, separation of CCC and EtDHA was unnecessary for reuse. The present method is considered to meet the requirements for industrial utilization, in which simplicity in scaleup, high yields, compact reaction system, and minimal formation of by‐products are important factors.
Microwave‐assisted catalytic transfer hydrogenation of safflower oil
Authors: Prabhavathi Devi B. L. A. , Karuna M. S. L. , Narasimha Rao K. , Saiprasad P. S. , Prasad R. B. N. 
Published: November 2006

AbstractCatalytic transfer hydrogenation (CTH) of safflower oil was studied using aqueous ammonium formate as hydrogen donor and palladium on carbon as catalyst in a closed vessel under controlled microwave irradiation conditions. The method offered good selectivity in complete reduction of linoleic acid to monounsaturated acid with a slight increase in stearic acid compared to other reported catalytic transfer hydrogenation methods. Selectivity was achieved by using microwave‐assisted CTH without employing an emulsifier or high ratios of water to oil.