bluuebunny/crossref_metadata_2025_split huggingface dataset:
Antioxidant activity of minor amounts of γ‐tocopherol in natural triacylglycerols
Authors: Lampi Anna‐Maija , Hopia Anu , Piironen Vieno 
Published: May 2007

AbstractThe effects of minor amounts of γ‐tocopherol on the oxidation of natural triacylglycerols (TAG) of rapeseed (RO) and butter oils (BO) were studied. Four different TAG materials were blended from chromatographically purified TAG that contained 100–25% of RO TAG. The RO TAG contained from <1 to 43 µg γ‐tocopherol per gram of TAG, which corresponded to ≤6% of the total tocopherols in the original RO. The TAG were held at 40°C in the dark for 4 wk and followed at regular intervals by measurements of hydroperoxide formation by peroxide values and of secondary product formation by p‐anisidine values at regular intervals. In all TAG, minor amounts of γ‐tocopherol retarded oxidation. In RO TAG, concentrations as low as 11 µg/g of γ‐tocopherol (1.5% of the total tocopherols in the original RO) were enough to decrease hydroperoxide and secondary product formation to 46 and 39%, respectively. The effect was even more important in TAG mixtures that contained BO TAG. There were no significant differences between oxidation of the RO TAG at 24 µg/g, the 75% RO TAG mixture at 11 µg/g, and the 50% RO TAG mixture at 3 µg/g of γ‐tocopherol. Even at these minor levels, γ‐tocopherol was a significant antioxidant, which is important in oxidation studies of purified model systems.
Optimization of arachidonic acid production by Mortierella alpina Wuji‐H4 isolate
Authors: Chen H. C. , Chang C. C. , Chen C. X. 
Published: May 2007

AbstractA fungal isolate Wuji‐H4 with a dense‐lobe rosette growth pattern on malt extract agar was identified as Mortierella alpina Peyronel. It was capable of producing 504 mg/L of arachidonic acid (AA) in the screening medium. Its AA content accounted for 42.4% of the total fatty acids. The AA yield was raised to 1,817 mg/L by a step‐by‐step approach, which uncovered that the preferred carbon source, nitrogen source, and temperature for fungal growth and lipid production were soluble starch, urea, and 24°C, respectively. Productivity was further optimized by exploiting the interactions between the constituents of the medium by the response surface method. A partial factorial design, followed by steepest ascent analysis, was carried out to locate the general vicinity of the optimal level of each nutrient. The response surface of AA production in this optimal region was then approximated with a full quadratic equation obtained from a three‐factor/five‐level central composite rotatable design. Maximum AA yield was predicted to occur in a medium that contained 99.7 g/L of soluble starch, 12.6 g/L of yeast extract, and 3.0 g/L of KH2PO4. Upon verification, the average experimental yield of AA (3,885 mg/L) was not significantly different from the predicted AA yield (3,940 mg/L), indicating that the response surface method had succeeded in exploiting the AA production potential of this new fungal isolate.
Analytical supercritical fluid extraction with lipase catalysis: Conversion of different lipids to methyl esters and effect of moisture
Authors: Snyder Janet M. , King Jerry W. , Jackson Michael A. 
Published: May 2007

AbstractThe fat content of lipid‐containing samples has been determined by extraction of the fat with supercritical carbon dioxide, followed by enzyme‐catalyzed methylation of the fat under supercritical conditions, prior to gas chromatography (GC) analysis. This study was initiated to determine the effect of moisture content on the extraction and conversion of lipids in oilseed and meat samples to their fatty acid methyl ester (FAME) derivatives. These samples were freeze‐dried or mixed with Hydromatrix and compared with untreated control samples by employing the above‐described supercritical fluid extraction‐reaction sequence. Particular attention was focused on minor constituents, such as phospholipids and cholesteryl esters, to see if they could be extracted and derivatized by the above technique. Recoveries and reaction conversions of the lipid species were determined with the aid of GC, high‐performance liquid chromatography, and supercritical fluid chromatography for analyses of the extracted lipids. Total fat values were higher from the freeze‐dried meat and oilseed samples than from samples mixed with Hydromatrix or left untreated. Extraction of cholesteryl esters was better than 90%, and conversion of the cholesteryl esters to FAME was 93% or higher. Extraction of phosphatidic acid was only 88% compared to more than 90% recoveries for the other phospholipid species. FAME conversion was better than 96% for all phospholipid samples in the study.
Enzymatic alcoholysis reaction of soy phospholipids
Authors: Ghosh M. , Bhattacharyya D. K. 
Published: May 2007

AbstractLipase‐catalyzed alcoholysis of soy phospholipids was investigated to simultaneously make lysophospholipids and fatty acid esters of individual alcohols. Alcoholysis was carried out by stirring a mixture of soy phospholipids and individual alcohols in equimolar proportions with 10% (by weight of reactants) Mucor miehei lipase at 55°C for 24 h. The products were isolated by column chromatography after removal of the lipase. Lysophospholipids (in 69–78% molar yield) were obtained from soy phospholipids, and the yield of esters of various alcohols also conformed nearly with theoretical yields.
Biotransformation of 12‐hydroxyoctadecanoic acid to 12‐hydroxyoctadecanamide by Bacillus cereus 50
Authors: Huang J K , Keudell K. C. , Klopfenstein W. E. , Wen L. , Bagby M. O. , Vesonder R. F. , Norton R. A. , Weisleder D. 
Published: May 2007

AbstractA new microbial isolate (Bacillus cereus 50) transformed 12‐hydroxyoctadecanoic acid to 12‐hydroxyoctadecanamide when grown aerobically in 1% yeast extract medium at 30°C, shaken at 250 rpm for 2 to 5 d. The compound was purified by thin‐layer chromatography and characterized by infrared, gas chromatography, mass spectrometry, and nuclear magnetic resonance. The yields of 12‐hydroxyoctadecanamide were 9.1 and 21.5% after 2 and 5 d, respectively.
Lipase‐catalyzed randomization of fats and oils in flowing supercritical carbon dioxide
Authors: Jackson M. A. , King J. W. , List G. R. , Neff W. E. 
Published: May 2007

AbstractEnzymes can frequently impart more selectivity to a reaction than chemical catalysts. In addition, the use of enzymes can reduce side reactions and simplify post‐reaction separation problems. In combination with an environmentally benign and safe medium, such as supercritical carbon dioxide (SC‐CO2), enzymatic catalysis makes supercritical fluids extremely attractive to the food industry. In this study, randomization of fats and oils was accomplished with an immobilized lipase in flowing SC‐CO2. Triglycerides, adsorbed onto Celite, are solubilized in CO2 and carried over 1–10 g immobilized lipase derived from Candida antarctica. The degree of randomization and rate of triglyceride throughput could be controlled by CO2 pressure and flow rate and quantity of enzyme used. The dropping points and solid fat indices of the resulting randomized oils were compared to oils that were randomized by conventional methods with sodium methoxide. Reversed‐phase high‐performance chromatography with flame‐ionization detection was used to quantitate changes in triglyceride composition of various substrates, such as palm olein and high‐stearate soybean oil. The resultant randomized oil mixtures have properties, e.g., solid fat index, that make them potential candidates for incorporation into traditional margarine formulations.
Chemoenzymatic production of (+)‐coriolic acid from trilinolein: Coupled synthesis and extraction
Authors: Gargouri Mohamed , Legoy Marie Dominique 
Published: May 2007

AbstractChemoenzymatic conversion of trilinolein to (+)‐coriolic acid was investigated in this work. Lipase‐catalyzed hydrolysis of trilinolein and lipoxygenation of liberated linoleic acid were coupled in a two‐phase medium that consisted of a pH 9 borate buffer and a water‐immiscible organic solvent (octane). High concentrations of trilinolein could be dissolved in the organic phase (up to 340 mM). Linoleic acid, liberated after hydrolysis, transferred to the aqueous phase and was enzymatically converted to the preferred 13(S)‐hydroperoxy‐9Z,11E‐octadecadienoic acid with soybean lipoxygenase‐1. This product, which remained in the aqueous phase, could be recovered by centrifugation and then chemically reduced to (+)‐coriolic acid (purity >95%). Recovery of this compound by liquid‐liquid extraction was easy. The structure of (+)‐coriolic acid has been confirmed by 1H nuclear magnetic resonance spectroscopy, mass spectrometry, and infrared spectroscopy. High yields were obtained with pure trilinolein or sunflower oil as initial substrates.
Studies on phytosterol oxides. I: Effect of storage on the content in potato chips prepared in different vegetable oils
Authors: Dutta Paresh Chandra , Appelqvist Lars‐Åke 
Published: May 2007

AbstractPotato chips fried in palm oil, sunflower oil, and high‐oleic sunflower oil were studied for the content of different phytosterol oxides during 0 to 25 weeks of storage in the dark. Oxidation products of sitosterol (24α‐ethyl‐5‐cholesten‐3β‐ol) and campesterol (24α‐methyl‐t‐cholesten‐3β‐ol) were synthesized to help identify the phytosterol oxides. The oxides of phytosterols were analyzed by preparative thin‐layer chromatography, solid‐phase extraction, capillary column gas chromatography (GC), and GC‐mass spectrometry. Epimers of 7‐hydroxysitosterol and 7‐hydroxycampesterol; 7‐ketositosterol and 7‐ketocampesterol; epimers of 5,6‐epoxy‐sitosterol and 5,6‐epoxy‐campesterol; 24α‐ethylcholestane‐3β,5,6β‐triol (dihydroxysitosterol) and 24α‐methylcholestane‐3β,5,6β‐triol (dihydroxycampesterol) were detected and quantitated in the samples of chips fried in different vegetable oils. Potato chips fried in palm oil had the lowest level of total sterol oxides, ranging from 5 to ca. 9 ppm in the lipids from time 0 to 25 wk of storage. The level of total sterol oxides in chip samples fried in sunflower oil ranged from 46 to 47 ppm, and the lipids in samples fried in high‐oleic sunflower oil ranged from 35 to 58 ppm from 0 time to 25 wk of storage. During 25 wk of storage no considerable increase in sterol oxides was observed in the samples of chips fried in palm oil and sunflower oil. The chip samples fried in high‐oleic sunflower oil had slightly higher levels of sterol oxides after 10 and 25 weeks of storage. In addition to the levels of individual sterol oxides, a new method for enrichment of phytosterol oxides from the unsaponifiables and full‐scan mass spectra of various oxidation products of sitosterol and campesterol are reported in this paper.
Studies on phytosterol oxides. II: Content in some vegetable oils and in French fries prepared in these oils
Authors: Dutta Paresh Chandra 
Published: May 2007

AbstractHydrogenated rapeseed oil/palm oil blend, sunflower oil and high‐oleic sunflower oil, and French fries fried in these oils were assessed for contents of sterol oxidation products. Different oxidation products of phytosterols (7α‐ and 7β‐hydroxy‐sito‐and campesterol, 7‐ketosito‐ and 7‐ketocampesterol, 5α,6α‐epoxy‐sito‐ and campesterol, 5β,6β‐epoxy‐sito‐and campesterol, dihydroxysitosterol and dihydroxycampesterol) were identified and quantiated by gas chromatography (GC) and GC‐mass spectroscopy. Rapeseed oil/palm oil blend contained 41 ppm total sterol oxides before frying operations. After two days of frying, this level was increased to 60 ppm. Sunflower oil and high‐oleic sunflower oil had 40 and 46 ppm sterol oxides, respectively, before frying operations. After two days of frying operations, these levels increased to 57 and 56 ppm, respectively. In addition to campesterol and sitosterol oxidation products, small amounts of 7α‐ and 7β‐hydroxystigmasterol were detected in the oil samples. Total sterol oxides in the lipids of French fries fried at 200°C in rapeseed oil/palm oil blend, sunflower oil, and high‐oleic sunflower oil were 32, 37, and 54 ppm, respectively. The levels of total oxidized sterols, calculated per g sample, ranged from 2.4 to 4.0 ppm. In addition to the content of phytosterol oxides, full scan mass spectra of several oxidation products of stigmasterol are reported for the first time.
Effect of processing on flavor precursor amino acids and volatiles of sesame paste (tehina)
Authors: Shahidi F. , Aishima T. , Abou‐Gharbia H. A. , Youssef M. , Shehata A. Adel Y. 
Published: May 2007

AbstractThe content of flavor precursor free amino acids in dehulled sesame seeds, subjected to roasting (R), steaming (S), roasting plus steaming (RS) and microwaving (M), was determined and compared with those of the raw (RW) seeds. R, RS, and S had major effects in reducing the content of free amino acids from 2360 µg/g to 582, 795 and 884 µg/g, respectively; M had no effect on the content of free amino acids. Meanwhile, flavor volatiles of the raw and processed seeds were compared by means of a dynamic headspace analyzer/gas chromatograph‐mass spectrometer. Volatiles of RW seeds contained 85 compounds, whereas under the analytical conditions employed, seeds subjected to R, RS, S, and M had 117, 97, 93 and 87 compounds, respectively. Among volatiles identified in the RW seeds were 36 hydrocarbons, 8 aldehydes, 4 ketones, 8 alcohols, 2 acids, 2 esters, and 1 pyrazine. The only pyrazine identified in the RW seeds was 2,5‐dimethylpyrazine. Pyrazines, generally recognized as contributors to the roasted aroma of foods, were more numerous (10 in R, 6 in RS, 2 in S, and 2 in M) and prevalent (8.71% in R, 2.97% in RS, 2.04% in S, 0.53% in M, and 0.25% in RW) in the volatiles of processed sesame seeds. The chemical nature of pyrazines also depended on the process employed. Multivariant analysis indicated a highly negative correlation between the loss of free amino acids and production of volatile flavor compounds in the R and RS samples, while the M sample remained unchanged. Furthermore, both R and RS seeds contained dimethyl sulfide and dimethyl disulfide, whereas no sulfur‐containing compounds were present in other samples. Of the processed seeds, the flavors of R and RS samples were considered as acceptable, and the flavor intensity of the former was deemed stronger than that of the latter by the experimenters.
Soy hull as an adsorbent source in processing soy oil
Authors: Gnanasambandam R. , Proctor A. 
Published: May 2007

AbstractSoy hull, a co‐product of the soybean industry, was evaluated as an adsorbent source for processing soy oil. Ground soy hull (<100 mesh), boiled soy hull, and soy hull carbon were each added to crude soy oil at various levels in the laboratory under commercial bleaching conditions. The free fatty acid (FFA), peroxide value (PV), pigments, and total phospholipid contents (PL) of treated samples were measured. The microstructure (scanning electron microscopy, SEM), X‐ray diffraction patterns (XRD), and Fourier transform infrared (FTIR) spectra of the soy hull adsorbents were also examined. The soy hull carbon was more efficient as an adsorbent relative to the ground or boiled soy hulls. The differences between ground and boiled soy hulls in the reduction of FFA were not significant. The effectiveness of adsorbents to reduce PV was: soy hull carbon > boiled soy hull = untreated soy hull; and for PL adsorption: soy hull carbon = ground soy hull > boiled soy hull. Boiling resulted in an open, porous structure, as evident from the SEM data, but carbonization did not affect the particle size. The XRD patterns of ground and boiled soy hulls were similar to those of powdered amorphous cellulose, but the carbon was more amorphous and had a random structure, as well as a more polar surface, as revealed by the FTIR spectra.
Statistical evaluation of biodegradation of news ink vehicles and ink formulations
Authors: Erhan S. Z. , Bagby M. O. , Nelsen T. C. 
Published: May 2007

AbstractSoybean oil, commercial news ink vehicles—consisting of either soy or mineral oil and petroleum resins—and United States Department of Agriculture’s (USDA) 100% modified soy oil‐based vehicles were subjected to biodegradation. Soybean oil and each vehicle were inoculated with monocultures and a mixed culture of Aspergillus fumigatus, Penicillium citrinum, and Mucor racemosus. Fermentations were allowed to proceed for 5, 12, and 25 d. Results show that, in 25 d, soy oil was degraded the most, followed by the USDA’s ink vehicles (USDA I–III), Newspaper Association of America’s (NAA) hybrid soy oil‐based and commercial mineral oil‐based vehicles. Some differences were found in the abilities of the cultures to degrade the different inks. Color did not appear to affect the degradation rate in soy oil, the USDA inks, or the NAA ink but was a factor in the commercial ink.
Pseudohalogenation of methyl 9‐hydroxy‐cis‐12‐and 12‐hydroxy‐cis‐9‐octadecenoate
Authors: Naqvi Fehmida , Rauf Abdul , Siddiqui M. M. , Ahmad M. S. , Osman S. M. 
Published: May 2007

AbstractPseudohalogenation of methyl 9‐hydroxy‐cis‐12‐octadecenoate (I) and methyl 12‐hydroxy‐cis‐9‐octadecenoate (II) has been carried out with N,N‐dibromobenzenesulfonamide (NNDBS). Compounds I and II, on reaction with NNDBS, formed four and three products, respectively. The interesting feature of these reactions was the formation of 1,4‐epoxy compounds. The structures of individual compounds were established with the help of elemental and spectral analysis.
Lipid composition and oxidative stability of oils in hazelnuts (Corylus avellana L.) grown in New Zealand
Authors: Savage G. P. , McNeil D. L. , Dutta P. C. 
Published: May 2007

AbstractHazelnut (Corylus avellana L.) samples were collected from six different cultivars of trees grown in an experimental orchard at Lincoln University. Three U.S. commercial cultivars (Butler, Ennis, and Barcelona), two European commerical cultivars (Tonda di Giffoni and Campanica), and one New Zealand selection (Whiteheart) were evaluated. The total oil, stability to oxidation of the oil, and fatty acid, tocopherol, and sterol composition were determined on samples of freshly extracted hazelnut oil. The total oil content of the seeds ranged from 54.6 to 63.2% while the stability of the oil, as measured by the Rancimat test ranged from 15.6 to 25.3 h. The content of the monounsaturated oleic acid in the oils ranged from 73.8 to 80.1% of the total fatty acids, while the tocopherol content ranged from 225.8 to 552.0 mg/g freshly extracted oil. The major desmethylsterols were sitosterol, ranging from 1416 to 1693 µg/g, campesterol, ranging from 78 to 114 µg/g, and Δ5‐avenasterol, ranging from 110 to 170 µg/g. The oil extracted from the cultivar Whiteheart was more stable (measured by Rancimat) than the oil from all other cultivars grown at the same location and under the same conditions. Whiteheart contained higher levels of total and γ‐tocopherol when compared to the other cultivars. The higher levels of tocopherol in Whiteheart help to explain the greater stability of the oil during the oxidative stress test. These results suggest that nuts from the cultivar Whiteheart could be stored longer than the other nuts tested.
Content of trans‐fatty acids in edible margarines
Authors: Tsanev R. , Russeva A. , Rizov T. , Dontcheva Iv. 
Published: May 2007

AbstractFatty acid composition, including trans‐isomers, was determined for four types of imported margarines consumed by the Bulgarian population. The results were compared with data obtained from a Bulgarian edible margarine produced under German license. Fatty acid composition and trans‐isomer content were determined by gas chromatography of fatty acid methyl esters on a packed and capillary column, respectively. The total contents of trans‐isomers of oleic and linoleic acid were within the ranges of 1.9–8.0% and 0.4–1.4%, respectively. The Bulgarian margarine contained similar quantities of trans‐isomers.
Influence of moderate amounts of trans fatty acids on the formation of polyunsaturated fatty acids
Authors: Bysted Anette , Hølmer Gunhild , Lund Pia 
Published: May 2007

AbstractThe effect of trans fatty acids from partially hydrogenated soybean oil and butterfat on the formation of polyunsaturated fatty acids was investigated. Five groups of rats were fed diets that contained 20 wt% fat. The content of linoleic acid was adjusted to 10 wt% of the dietary fats in all diets, whereas the amount of trans fatty acids from partially hydrogenated soybean oil (PHSBO) was varied from 4.5 to 15 wt% in three of the five diets. The fourth group received trans fatty acids from butterfat (BF), while the control group was fed palm oil without trans fatty acids. Trans fatty acids in the diet were portionally reflected in rat liver and heart phosphatidylethanolamine (PE), phosphatidylcholine (PC), phosphatidylinositol, and phosphatidylserine. Incorporation in the sn‐1 position was compensated by a decrease in saturated fatty acids. Trans fatty acids were not detected in diphosphatidylglycerol. Compared to the presence in the dietary fats, 8t‐ and 10t‐18:1 were discriminated against in the incorporation in PE and PC from liver and heart, whereas 9t‐ and 12t‐18:1 were preferred. The formation of 20:4n‐6 was not influenced by 4.5 wt% trans fatty acids (from PHSBO) but apparently was by 10 wt% in liver. In contrast, even a content of 2.5 wt% trans fatty acids from BF reduced the formation of 20:4n‐6. The inhibitory effect of trans isomers on linoleic acid conversion was reflected less in heart than in liver and less for PE than for PC. Groups with trans fatty acids showed increased 22:6n‐3 and 22:5n‐3 deposition in liver and heart PE and PC.
Effects of steeping conditions during wet‐milling on the retentions of tocopherols and tocotrienols in corn
Authors: Wang Chunyang , Ning Jing , Krishnan Padmanaban G. , Matthees Duane P. 
Published: May 2007

AbstractVitamin E is a natural antioxidant that plays significant roles in food preservation and disease prevention. There are eight naturally occurring vitamin E isomers (tocols): α‐, β‐, γ‐, and δ‐tocopherols and α‐, β‐, γ‐, and δ‐tocotrienols. Corn oil is a major source of vitamin E. Most of the corn oil produced in the United States is a co‐product of corn wet‐milling. There is limited knowledge about the effects of corn wet‐milling on the retention of these vitamin E isomers. A high‐performance liquid chromatography method was developed for simultaneous determinations of tocols in steeped corn samples. Effects of steeping conditions (steeping time and SO2 concentration) on retention of tocols in corn were investigated. α‐Tocopherol, γ‐tocopherol, α‐tocotrienol, and γ‐tocotrienol are the predominant vitamin E isomers in the corn variety used in the study. Steeping conditions had little effect on the concentration of α‐tocopherol and α‐tocotrienol. However, a higher concentration of SO2 and a shorter steeping time gave a slightly higher γ‐tocotrienol content and lower γ‐tocopherol content. Corn kernels steeped in a vitamin C solution had a much higher concentration of the tocols than those steeped in SO2 solution.
Synthesis of polyfunctional glycerol esters: Lipase‐Catalyzed esterification of glycerol with diesters
Authors: Villeneuve P. , Foglia T. A. , Mangos T. J. , NuɁez A. 
Published: May 2007

AbstractThe enzymatic esterification of glycerol with dicarboxylic acids or esters was studied to produce mono‐ and/or diesterified glycerol adducts. Such materials are useful synthons in the synthesis of biodegradable polymers and surfactants. In this work two strategies were studied for preparing these prepolymeric glycerol derivatives: the lipase‐catalyzed esterification of free glycerol with diacids or esters and the reaction of supported or protected glycerol with diesters. For example, reaction of isopropylidene glycerol with dimethyl sebacate gave a >95% yield of isopropylidene glycerol‐monomethyl sebacate ester. Reaction of glycerol supported on silica with dimethyl adipate gave a 40% yield of glycerol‐monomethyl adipate ester. Best yields of glycerol‐mono‐ and diesters (70% and 10%, respectively) were obtained by direct esterification of free glycerol with a diester in a solvent‐free system containing small amounts of water (<4%).