bluuebunny/crossref_metadata_2025_split huggingface dataset:
The autoxidative contraction of monolayers of linoleic acid at a gas‐water interface
Authors: Porter W. L. , Henick A. S. , Clifford M. 
Published: January 2007

AbstractA monolayer of linoleic acid spread at an airwater interface was found to undergo an immediate oxygen‐dependent contraction when compressed at a constant high film pressure. This is in contrast to the expansion of monolayers of other unsaturated acids at lower film pressures as reported by other workers. The process shows quasi‐first‐order kinetics, and there is little evidence for an induction period, in contrast to bulk‐phase autoxidation.Initial rate of contraction is a function of pH between 6 and 9. This and other data suggest that contraction is due to the titration of the packed adjacent carboxyl groups in the monolayer and to the solution of short‐chain soaps resulting from the oxidative scission of linoleic acid.Although complete anaerobiasis prevented film contraction, neitherdl‐alpha‐tocopherol deposited in the film, nor hydroquinone in the substrate solution were inhibitory alone. Butylated hydroxyanisole (BHA) present in an aerobic gas phase produced inhibition of contraction of linoleic acid films spread on completely deaerated substrates. Inhibition was released upon removal of the BHA vapor, the restored rate in air approaching that before the BHA treatment. A method of specific testing of antioxidants is thus provided, which will differentiate between those presented in the vapor, the lipid, or the solution phases.
Degradation of lipids and glucosinolates in dehulled crambe seed during storage
Authors: Baker E. C. , Mustakas G. C. , McGhee J. E. 
Published: January 2007

AbstractCrambe as harvested contains seed accompanied by ca. one‐third hull, a fraction of little commercial value that can be removed during processing. If the hull were removed before shipping, considerable transportation costs could be saved. Because little was known about the quality of crambe seed after dehulling and storage, decomposition of the glucosinolates in dehulled seed after storage was studied, as well as changes in color, free fatty acids, peroxide value, and ease of hydrogenation of the oil fraction. While not so stable as seed plus pericarp (hull), dehulled crambe seed can be stored for at least 3 months at temperatures up to 110F at ambient moisture (6.3%). However, at 14% moisture, decomposition was significant after storage for 2 weeks at both ambient (77 F) and elevated (110 F) temperatures. Inactiviation of the endogenous enzyme after dehulling extends storage life to 3 months at either moisture level at ambient temperatures.
Chlorophyll adsorption by alumina‐pillared acid‐activated clays
Authors: Mokaya Robert , Jones William , Davies Mary E. , Whittle Mavis E. 
Published: January 2007

Clays, acid‐activated to an optimum level, have been pillared with alumina to give semi‐crystalline expanded materials with surface acidities, pore volumes and average pore diameters generally higher than those of the corresponding pillared materials derived from a clay matrix not previously acid‐activated. The chlorophyll adsorption capacity of the pillared acid‐activated materials is significantly greater than that of pillared, nonactivated clays.The procedures used in the preparation of these pillared acid‐activated clays (i.e., temperature of pillaring, method of drying and calcination temperature) have a significant influence on chlorophyll adsorption capacity because they influence both the physical and the chemical properties of the final pillared material. This variation provides a useful means of relating the various properties of the pillared materials to the chlorophyll adsorption capacity. As a result, a correlation has been demonstrated between adsorption capacity and a combination of pore volume and number of strong acid sites (of strength pKa < −1.5) present in the pillared material. Optimal adsorbents were obtained from freeze‐dried samples prepared by exchange at 20°C and calcination in air at 500°C.
The use of thiobarbituric acid as a measure of fat oxidation
Authors: Sidwell C. G. , Salwin Harold , Benca Milada , Mitchell J. H. 
Published: January 2007

SummaryAn evaluation of thiobarbituric acid (TBA) as an agent for the measurement of fat oxidation was made by the application of several empirical procedures to animal and vegetable fats. An extraction procedure was used for removing the products of oxidation. The reaction with TBA was conducted in a boiling water bath to produce a red color, which was then estimated spectrophotometrically.Fats stored at −20, 0, 72, and 100°F. (−29, −18, 22, and 38°C.) and fats oxidized by the active oxygen method (A.O.M.) and by ultraviolet irradiation were examined. It was found that the TBA test might be of value in following the course of oxidation of cottonseed oil and soybean oil in the A.O.M. apparatus. Higher TBA values were obtained for soybean oil than cottonseed oil at comparable peroxide values. This is of interest because of the greater tendency of soybean oil to develop oxidized flavors. The volatile reaction products of oxidation were collected in toluene, and a comparison of the TBA values at comparable peroxide values of lard, cottonseed and soybean oils showed that the soybean oil volatiles developed the greatest intensity of color.
Detoxification of cottonseed by salts and alkalies
Authors: Eagle Edward , Bialek H. F. , Davies D. L. , Bremer J. W. 
Published: January 2007

SummaryIn a series of four tests in which three deliberately chosen toxic cottonseed meals were treated with aqueous solutions of salts and alkalies, it was found that the best detoxifying effect was obtained with sodium hydroxide, followed very closely by potassium and ammonium hydroxides.Dry heat treatment alone did not detoxify, and mortality was high. Treatment with moisture plus heat gave partial detoxification. Of the 22 chemically‐treated cottonseed meal samples tested, those treated with alkalies showed the best weight gains, the order of decreasing effectiveness being
urn:x-wiley:0003021X:media:aocs0121:equation:aocs0121-math-0001The residual toxicity of treated cottonseed meals cannot be explained on the basis of their free gossypol content as analyzed for meals with high values gave better growth performance than some with lower levels of free gossypol. There were also very marked differences in final body weight after 8 weeks of feeding six different treated cottonseed meal samples having practically the same free gossypol content.
Nomographs for calculating the fatty acid composition of oils and fats from iodine values and either extinction coefficients or thiocyanogen values
Authors: Narayan K. Ananth , Kulkarni B. S. 
Published: January 2007

SummaryVery few alignment charts are available which can be used for routine calculations in fat analysis and processing. Three alignment charts are presented in this communication for determining the fatty acid composition of a fatty acid mixture consisting variously of linolenic, linoleic, oleic, and saturated fatty acids or glycerides, incorporating for accuracy, data based on ultraviolet extinction coefficients. In two of the charts triangular diagrams have been used as a novel feature in nomography to give directly the fatty acid composition.
Determining the density of triglycerides and esters by the falling drop method
Authors: Sims R. P. A. 
Published: January 2007

SummaryThe densities of triglyceride oils and their esters have been determined by the Falling Drop Method to within ±0.0003 when the behavior of two drops is compared and to ±0.0002 when only one drop is employed. Triolein and methyl erucate have been used as reference materials and solutions of ethanol in water as media. Errors due to variation in temperature have been analyzed for the systems and apparatus employed.
Reactions of fatty acid chlorides. I. Preparation of fatty acid anhydrides
Authors: Sonntag N. O. V. , Trowbridge J. R. , Krems I. J. 
Published: January 2007

SummaryThe anhydrides of decanoic, lauric, myristic, palmitic, stearic, and oleic acids have been prepared in better than 90% yields through the corresponding acid chlorides with acetic anhydride. Oleic anhydride could only be prepared satisfactorily when oleoyl chloride was prepared, in turn, with oxalyl chloride. A comparison has been made of the various synthetic methods.
Determination of the extent of rancidity of soybean oil by gas chromatography compared with peroxide value
Authors: Jarvi P. K. , Lee G. D. , Erickson D. R. , Butkus E. A. 
Published: January 2007

AbstractThe development of rancidity in soybean oil has been studied by gas chromatography (GC), peroxide value (PV) and sensory evaluation. The GC method has been adapted from previous methodology and another type of column packing has been used for the purpose. The GC peaks have been treated as one whole group, and and oxidation value (OV) has been computed by means of an internal standard (n‐octanol). The OV’ have been correlated with the PV’s. The flavor of soybean oil and a blend of 50% soybean oil and 50% hydrogenated soybean oil, both kept at 60 C for varying lengths of time, was evaluated by a panel and the results have been presented in a new graphical form. A relationship between the OV and the flavor of the fat has been demonstrated. The merits of the method are discussed.
Antioxidant effects of chlorophyll and pheophytin on the autoxidation of oils in the dark. II. The mechanism of antioxidative action of chlorophyll
Authors: Endo Yasushi , Usuki Riichiro , Kaneda Takashi 
Published: January 2007

AbstractTo understand the mechanism of the antioxidant effect of chlorophyll on the autoxidation of oils in the dark, antioxidant activities of several derivatives of chlorophyll were compared. Antioxidant activities were observed in chlorophyll derivatives such as protopor‐phyrin methyl ester and its magnesium chelated compound. Porphyrin seems to be an essential chemical structure for the antioxidant activity of chlorophyll. Chlorophyll did not decompose the hydroperoxides, but reduced free radicals such as 1,1‐diphenyl‐2‐picrylhydrazyl. Electron spin resonance spectrum of the π‐cation radical was recorded during the oxidation of chlorophyll in methyl linoleate solution. These observations suggest that chlorophyll may act as a hydrogen donor to break the chain reaction.
Production of 9‐hydroperoxy‐γ‐linolenic acid by soybean lipoxygenase in a two‐phase system
Authors: Hiruta Osamu , Nakahara Toro , Yokochi Toshihiro , Kamisaka Yashushi , Suzuki Osamu 
Published: January 2007

Abstract9‐Hydroperoxy‐γ‐linolenic acid (9‐GOOH) was produced selectively by soybean lipoxygenase (LG) from γ‐linolenic acid (GLA) using a two‐phase (borate buffer, pH 6.5/hexane) system at a low temperature (10°C) with some anionic surfactants that showed little inhibitory effect on the enzyme at pH 6.5. The system avoided the inhibitory effect of a higher substrate concentration and of hydroperoxide as well as low substrate solubility in an aqueous system. Not lipoxygenase‐2 (LG2) but lipoxygenase‐1 (LG1) was indicated to be responsible for the production of 9‐GOOH. Among the anionic surfactants examined, acetate and sarcosinate were shown to be suitable, but phosphate was not. Ca2+ increased the 9‐GOOH productivity. The LG1 fraction gave the maximum yield of 35% with 0.5 mM Ca2+, ECT‐3N (anionic surfactant, acetate) at 10°C and at 4.8 mM GLA in an emulsion.
Modified butyrometric method for rapid determination of fat in seeds
Authors: Ali Rashda , Khan M. Nasir 
Published: January 2007

AbstractButyrometers, the specific tubes for fat determination in dairy products, were used successfully in estimation of fats in commercially important seeds such as soybean, peanut, coconut, pinenut, walnut, sesame, almond and poppy seeds. The method is simple, rapid and economical; the results are reproducible and comparable to the standard methods for fat estimation such as the Soxhlet and solvent extraction.
Quality of nigerian palm oil after bleaching with local treated clays
Authors: Nkpa Nnadozie N. , Arowolo T. A. , Akpan H. J. 
Published: January 2007

AbstractLaboratory investigations into the possibility of using local Nigerian clays in refining the Nigerian crude palm oil revealed that the Okija clay may possess some potential as an adsorptive cleanser in the refining process. Activated bentonite was used as the standard clay of comparison, and the performance of two local natural clays, leached with various concentrations of sulfuric acid, was evaluated for their use as alternative adsorptive cleansers in refining Nigerian crude palm oil. Measurements of peroxide values, para‐anisidine values, carotene content and stabilities of the oils using the active oxygen method were used in assessing the relative performance of the clays.The clays exhibited similar trend of effects on identical batches of alkali‐neutralized palm oil. In one set of experiments poor results were obtained when the degummed and alkali‐neutralized palm oil was treated with clays leached with sulfuric acid at concentrations of 1M and 4M. Better results were obtained at acid concentrations of 2M and 3M. Bentonite proved better than Okija clay when the leaching was performed with 2M H2SO4, but both clays had comparable effectiveness when 3M H2SO4 was used for leaching. The Nsu clay gave the least encouraging results. In another series of experiments the results showed that for various dosages of clay, up to 3% by weight of the oil to be refined, the oxidative stability of the processed oil was reasonably good for an oil which was neither deodorized nor treated with antioxidants.
Production of dihomo‐γ‐linolenic acid byMortierella alpina 1S‐4
Authors: Shimizu Sakayu , Akimoto Kengo , Kawashima Hiroshi , Shinmen Yoshifumi , Yamada Hideaki 
Published: January 2007

AbstractThe mycelial dihomo‐γ‐linolenic acid content of an arachidonic acid‐producing fungus,Mortierella alpina 1S‐4, was found to increase, with an accompanying marked decrease in its arachidonic acid content, on cultivation with sesame oil. The resultant mycelia were found to be a rich source of dihomo‐γ‐linolenic acid. This unique phenomenon was suggested to be due to specific repression of the conversion of dihomo‐γ‐linolenic acid to arachidonic acid by the oil. After fractionation of the oil with acetone into oil and non‐oil fractions, it was found that the effective factor(s) was present in the non‐oil fraction. In a study on optimization of the culture conditions for the production of dihomo‐γ‐linolenic acid byM. alpina 1S‐4, a medium containing glucose, yeast extract and the non‐oil fraction was found to be suitable for the production. Under the optimal conditions in a 50‐1 fermentor, the fungus produced 107 mg of dihomo‐γ‐linolenic acid/g dry mycelia (2.17 g/l of culture broth). This value accounted for 23.1% of the total fatty acids in the lipids extracted from the mycelia. The mycelia were also rich in arachidonic acid (53.5 mg/g dry mycelia, 11.2%). Other major fatty acids in the lipids were palmitic acid (24.1%), stearic acid (7.0), oleic acid (20.1), linoleic acid (6.6) and γ‐linolenic acid (4.1).
Lipase biocatalysis in the production of esters
Authors: Linko Y. ‐Y. , Lämsä M. , Huhtala A. , Rantanen O. 
Published: January 2007

AbstractLipase biocatalysis was investigated as a tool for the production of butyl oleate and rapeseed oil 2‐ethyl‐1‐hexyl ester by esterification and transesterification, respectively. We screened 25 commercially available lipases and found that butyl oleate was produced at high yields from oleic acid and 1‐butanol by lipases fromCandida rugosa, Chromobacterium viscosum, Rhizomucor miehei, and Pseudomonas fluorescens. The initial water content of the system, lipase quantity, and the molar ratio of 1‐butanol to oleic acid were important factors in influencing the ester yield. In general, no ester was formed without the addition of water. The exception wasCh. viscosum lipase, which yielded 98% of ester in 12 h with 1‐butanol excess without additional water. The addition of 3.2% water increased the initial rate of reaction. With an oleic acid excess and only 0.3% lipase,C. rugosa andR. miehei lipases yielded 94 and 100% esters with initial water contents of 3.2 and 14%, respectively. Lipase‐catalyzed alcoholysis of low‐erucic acid rapeseed oil and 2‐ethyl‐1‐hexanol without additional organic solvent also was studied in stirred batch reactors. In this case,C. rugosa lipase was the best biocatalyst with an optimal 2‐ethyl‐1‐hexanol to rapeseed oil molar ratio of 2.8, a minimum of 1.0% added water, and 37°C. An increase in temperature up to 55°C increased the rate of reaction but did not affect the final ester yield. The enzyme was inactivated at 60°C. Under optimal conditions, the ester yield increased from 88% in 7 h to nearly complete conversion in 1 h when the lipase content was increased from 0.3 to 14.6%. In a 2‐kg small pilot scale, up to 90% conversion (97% of theoretical) was obtained in 8 h at 37°C with 3.4% lipase in the presence of Amberlite XAD‐7 resin with 3% added water.
Biochemical and cytochemical transformations in germinating coconut (Cocos nucifera Linn.)
Authors: Balachandran C. , Arumughan C. 
Published: January 2007

AbstractThe mechanism of mobilization and utilization of lipids by the developing seedling and the involvement of different tissues in this process was examined in germinating coconut. The endosperm (lipid reserve) and haustorium (spongy tissue developed during germination) were separated from germinating coconuts at intervals of two weeks up to week 22, and assayed for lipase, isocitrate lyase, malate synthase, and catalase, as well as for lipids and sugars. Except for lipase, activities of all the other enzymes were absent in the endosperm during the entire period of germination. However, these enzymes were found to be activated after the tenth week after germination and plateaued at week 16. Induction of these enzymes indicated the operation of the glyoxylate cycle in the haustorial tissue. Glyoxysomes also were observed in the haustorium. The haustorium was shown to absorb triacylglycerol and free fatty acids from endosperm for subsequent conversion to sugars in this tissue. Haustorium therefore is a biochemically active tissue and is the site of operation of the glyoxylate cycle in germinating coconut.
Application of enzyme‐assisted aqueous fat extraction to cocoa fat
Authors: Tano‐Debrah Kwaku , Ohta Yoshiyuki 
Published: January 2007

AbstractAn enzyme‐assisted aqueous fat extraction method was used to extract fat from dry cocoa beans. The beans were dehulled and finely ground. Samples were mixed with water in predetermined ratios. A protease and an enzyme with high activities of both cellulase and hemicellulase were added at 1% of the sample weight, mixed, and incubated for about 6 h at 37°C. The treated samples were then extracted by a water flotation technique. The preextraction treatment with enzymes effectively increased fat yield by about 26%. The observation suggests that the enzyme‐assisted aqueous fat extraction method could improve the efficiency of rural fats and oils technologies currently in use in many developing countries.
Long‐term stability studies on stored glycerol monostearate (GMS)‐effects of relative humidity
Authors: Robbins S. James , Nicholson Sherry H. 
Published: January 2007

AbstractThe long‐term hydrolysis and isomerizations that occurred in commercial glycerol monostearate (GMS) have been studied under controlled low relative humidity (ca. 30%) and high relative humidity (ca. 90–100%). Acid number values increased 2–3 units over an 84‐day period in high relative humidity, and only 0.5 unit in low humidity.Changes in the totalα‐monoglyceride,β‐monoglyceride,α,α′‐andα,β‐diglyceride concentrations with time offered a method to observe the processes involved. Changes in monoglyceride and diglyceride concentrations of GMS were monitored using the BSTFA [(N,O)‐bis(trimethylsilyl)trifluoroacetamide] derivative and fused silica capillary gas chromatography. Isomerization was shown to occur before any substantial hydrolysis. Decreases in concentration ofα,β orα,α′‐diglyceride (after isomerization was essentially complete) corresponded to the acid number rises observed.
Pigment removal from canola oil using chlorophyllase
Authors: Levadoux W. L. , Kalmokoff M. L. , Pickard M. D. , GrootWassink J. W. D. 
Published: January 2007

AbstractFrost‐damaged or prematurely harvested canola seed (rapeseed) may yield oil with a high chlorophyll content (50–60 µg/ml). Enzymatic hydrolysis of chlorophyll, added to buffer/surfactant, buffer/acetone or buffer/acetone/canola oil, to produce water‐soluble chlorophyllide (green pigment) was studied using a crude chlorophyllase preparation (acetone‐dried chloroplasts) from 15 to 20‐day‐old sugar beet seedlings. In buffer/surfactant, the optimum pH for enzyme activity was temperature dependent. At 30 C and 0.24% Triton X‐100 (or 30% acetone), chlorophyllase showed maximum activity toward a crude chlorophyll preparation over the range of pH 8–10. At 60 C, the activity was more than twofold higher, with a sharp maximum at ∼pH 8. Mg2+ enhanced the activity with an optimal concentration of 50 mM. At pH 7.5, 50 C and in the presence of only 6% acetone, the enzyme showed high affinity for chlorophyll (Km=15µM or 13.5 µg/ml), suggesting that the natural chlorophyll concentrations found in green canola oils might facilitate high enzymatic efficiencies. The crude enzyme was stable in buffer/acetone at pH 7.5 and 50 C for at least two hr.With acetone concentrations as low as 6%, maximum enzyme activities in buffer and buffer/canola oil required intensive mixing (homogenization) of the various substrate, enzyme and liquid phases. In general, the rate and extent of chlorophyll hydrolysis were greater in buffer than in buffer/oil. In both reaction systems, chlorophyll hydrolysis slowed down with time due to accumulation of phytol, which proved to be a competitive inhibitor (Ki=11 µM or 3.3 µg/ml). The other hydrolysis product, chlorophyllide, did not affect enzymatic activity.Crude canola oil used in the reconstitution of green oil did not support enzymatic chlorophyll hydrolysis without prior degumming and desoaping. The optimum buffer/oil ratio of the reaction mixtures was above 2/1 (v/v).
cis‐Vaccenic acid in pulp lipids of commonly available fruits
Authors: Shibahara Akira , Yamamoto Kohei , Nakayama Takao , Kajimoto Goro 
Published: January 2007

AbstractFatty acids of commonly available fruit pulps have been analyzed by capillary gas chromatography of their methyl esters and by gas chromatography‐mass spectrometry as their dimethyl disulfide adducts. The gas chromatographic and mass spectrometric data proved that these fruits always containedcis‐vaccenic (cis‐11‐octadecenoic) acid as a component fatty acid of their pulp lipids. The concentration ofcis‐vaccenic acid in total octadecenoic acids ranged from 1.9% to 95.1% in the fruit pulps examined. The highest concentration of this acid was detected in pulp lipids of Japanese persimmon (Diospyros kaki). In fruit pulp lipids,cis‐vaccenic acid was a common octadecenoic acid as well as oleic acid.
Autoxidative rates of nonmethylene‐interrupted polyenoic fatty acids
Authors: Takagi Toru , Miyashita Kazuo 
Published: January 2007

AbstractAutoxidative rates of free fatty acids and methyl esters increased in the following order: oleic (c9–18:1), c5, c9–18:2, linoleic (c9,c12–18:2), c5,c9,c12–18:3, t5,c9,c12–18:3, and linolenic (c9,c12,c15–18:3). The increase of the rates due to the Δ5‐olefinic bond was much lower than that due to an olefinic bond extension in a methylene‐interrupted sequence. Agreement of the oxidative rates obtained from conjugated diene content with those obtained from POV showed that oxygen attack did not occur at the isolated olefinic bond, but at the methylene‐interrupted diene in the oxidation of 5,9,12–18:3. The Δ5‐olefinic bond may promote the oxidation of the methylene‐interrupted diene intramolecularly.