Abstracts

Sharp changes in the values of the Avrarni constant k and exponentn were observed for aU three fats around 20.0°e. Increases in naround 20.0°C indicated a change from one-dimensional ro multi-dimensional growth. Differences in k and n of MF-DAG fromAMF and MF-TAG suggested that the presence of milk fat diacyl-glycerols changes the crystal growth mechanism. Apparent freee~ergies of nucleation (AGc.apparall) were determined using theFisher-Turnbull model. AGc.appamu for AMF was significantlygreater than AGc.apparall for MF-TAG, and AGc,appamtt for MF-DAG was significantly less than those for both AMF and MF-TAG. The microstructural networks of AMF, MF-TAG, and MF-DAG, however, were similar at both 5.0 and 25.0°C, and all threefats crystallized into the typical W -2 polymorph. Differential scan-ning calorimetry in both the crystallization and melting modesrevealed no differences between the heat flow properties of AMF,MF-TAG, and MF-DAG.

Paper no. J9401 in JADes n, 463-475 (May 2000).

658

Rapid Determination of Total Trans Fat Content by AnenuaredTotal Reflection Infrared Spectroscopy: An InternationalCollaborative Study, Michael Adams, Magdi M. Mossobab, andTheresa lee", "Lipton, Baltimore, Maryland 21229, bFood andDrug Administration, Center for Food Safety and AppliedNutrition, Office of Scientific Analysis and Support, Washington,DC 20204, and CRoss Products Division, Abbon Laboratories,Columbus, Ohio 43216.

Interest in trans far labeling has prompred efforts to developnew, more efficient methods for rapidly and accurately deter-mining trans fat content in foods. The lower limit of quannra-non, 5% trans fat (as percent of total fat), of transmissioninfrared official methods, such as AOAC 994.14 and 965.34, forroral isclared trans Iarry acids is too high to be generally usefulfor the determination of low levels of trans fats in foods. A noveland rapid (5 min) attenuated total reflection Fourier transforminfrared (ATR-FfIR) spectroscopic procedure was recentlydeveloped and applied to food products. This procedure wasvoted official method AOes Cd 14d-99 by the American OilChemists' Society in 1999 after testing in a 12-1aboratory inter-national collaborative study. The results of this study aredescribed in this paper. Analytical ATR-FTIR results exhibitedhigh accuracy in the range investigated, 1-40% trans; resultstended to have <2% high bias relative to the gravimetricallydetermined values. The precision of this internal reflectionmethod was found to be superior to those of transmissioninfrared official methods. It is recommended that the applicabil-ity of the ATR-FfIR method be limited to tran5levels of >1% (aspercent of total far).

Paper no. J9366 in JADes 77, 457-462 (May 2000).

The Effect of Minor Components on Milk Fat Crystallization,Amanda J. Wrighr<l, Richard W. Harrelv, Scresh S. Narinee, andAlejandro G. Marangonis", Departments of «Food Science,University of Guelph, Ontario Canada NIG 2WI, and bFoodScience, University of Wisconsin-Madison, Madison, Wisconsin53706.

Milk fat is composed of 97-98% triacylgl)'cerols and 2-3%minor polar lipids. In this study rriacylglycerols were chromate-grnpbically separated from minor components. Isolared diacyl-glycerols from the polar fraction were also added back ro the milkfat triacylglycerols. The crystallization behaviors of native anhy-drous milk far (AMF), milk fat triacylglycerols (MF-TAG), andmilk fat rriacylglycerols with dincylglycerols added back (MF-DAG) were studied. Removal of minor components and additionof diacylglrcerols had no effect on dropping points or equilibriumsolid fat contents. Presence of [he minor components, however, diddelay [he onset of crysrallizarion at low degrees of supercooling.Crystallization kinetics were quanrified using the Avrami model.

Volume I I • June 2000 • In'orm

Analysis of Triacylglyceride Hydroperoxides in Vegetable Oils byNonaqueous Reversed-Phase High-Performance LiquidChromatography with Ultraviolet Detection, Christina Bauer-Plank" and Lisette Steeohorsr-Slikkerveer, Unilever ResearchVlaardingen, 3130 AC Vlaardingen, The Netherlands.

Triacylglyceride hydroperoxides (HPO-TAG), the primaryauroxidarion products of triacylglycerides (TAG), have been ana-lyzed in polyunsaturated vegetable oils by means of nonaqueousreversed-phase high-performance liquid chromatography(HPLC) with ultraviolet detection. Using a retention time modelbased on equivalent carbon numbers, mono- and bishydroperoxyTAG and hydroxy TAG could be identified. The correlationbetween the peroxide value (POV) determined by iodomemctitration and quantitative HPLC results for HPO-TAG was estab-lished for sunflower oil samples with POV between 0.5 and 50meq/kg. The recovery of HPO-TAG in the HPLC procedure wasfound to be close to 100% in the POV range of 4 to 71 meq/kg.Absolute quantitative results for HPO-TAG in sunflower oil sam-ples could not be obtained accurately, as molar extincrion coeffi-cients of HPO·TAG occurring in natural oils deviate from thoseof available HPO-TAG reference compounds.

Paper no. J9126 in JAOes 77. 477-482 (May 2000).

lsoflavcne Content Among MalUrity Group 0 to II Soybeans,Chunyang Wang', Marci Sherrard", Sudhakar Pagadala", ReginaWixona, and Roy A. Scorrh, Departments of «Nurririon and FoodScienc~, and bPlant Science, South Dakota State University,Brookings, South Dakota 57007.

This study reports the isoflavcne contents of 210 soybean cul-rtvars grown in South Dakota and explores possible relationsbetween isoflavone contents and agronomic characteristics. Totalisoflavone ccnrerus (normalized) ranged from 1161 to 2743l1g/g. A number of agronomic characteristics were documentedfor each variety including maturity group, hilum color, diseaseresistance, seed weight, yield, maturity (in days), and plant

height. Varieties in maruriry group I had significantly higher totalisoflavones when compared to maturity group O. Hilum colorwas related to differences in genisrin, daidzein, and genistein con-tent. No differences in isoflavone content were observed basedon disease resistance profiles. Genistein content was found 10 benegatively correlated with yield, days of maturity, and plantheight. Weak bur significant correlations also existed betweenthese agronomic characteristics and orher isoflavones.

Paper no. J8915 in JADes 77, 483-487 (May 2000).

Monitoring a Progressing Transesrerificarion Reaction by Fiber-Optic Near Infrared Spectroscopy with Correlation to 'HNuclear Magnetic Resonance Spectroscopy, Gerhard Knoche",ARS, USDA, NCAUR, Peoria, Illinois 61604.

Biodiesel is a promising alternative diesel fuel obtained fromvegerable oils, animal fats, or waste oils by transesterifying theoil or fat with an alcohol such as methanol. In an exrensicn ofprevious work, fiber-optic near infrared spectroscopy was usedto quantitatively monitor the transesterificarion reaction (6-Lscale) of a vegerable oit (soybean oil) to methyl scyere. Theresults were correlated with IH nuclear magnetic resonance spec-troscopy. The method described here can be applied to the trans-esterification of other vegetable oils.

Paper no. j9483 in JAOes 77, 489-493 (May 2000).

Lipase-Catalyzed Acidolysis of Tristearin with Oleic or CaprylicAcids to Produce Siructured Lipids, Vivienne V. Yankah andCasimir C. Akoh ", Department of Food Science and Technology,The Universlry of Georgia, Athens, Georgia 30602-7610.

Two different srrucrured lipids (SL) were synthesized by trans-esterifying tristearin with caprylic acid (C8:0) or oleic acid(CI8:!). The objective was to synthesize SL containing stearicacid (CI8:0) at the sn-2 position as possible nutritional and low-calorie fats. The reaction was catalyzed by IM60 lipase fromRhi:zomllcor miehei in the presence of u-hexaue. The effects ofreaction parameters affecting the incorporation of caprylic acidinto tristearin were compared with those for incorporating oleicacid into tristearin. For all parameters studied, oleic acid incor.porarlon was higher than caprylic acid. The range of conditionsfavorable for synthesizing high yields of C8:0-conraining SL wasnarrower than for oleic acid. An incubation time of '12-24 handan enzyme conrenr of 5% (w/w total subsrrares] favored C8:0iurorporarion, The mole percentage of incorporated CIS:I didnot increase further at enzyme additions greater than 10%.C18:1 incorporation decreased with the addition of more than10% water (w/w total substrates) to tbe rrisrearin-oleic acidreaction mixture. Increasing the mole ratio of fatty acid (FA) to

rriacylglycerol increased oleic acid incorporation. The highestC8:0 incorporation was obtained at a 1:6 mole ratio of tristearinto FA. Positional analysis confirmed that C18:0 remained at thesn-2 position of the synthesized SL. The melting profiles of tri-stearin-caprylic acid and tristearin-oleic acid SL displayed peaksbetween -20 to JO"C and -20 to 40°C, respectively. Their solidfat contents (~25%) at H·C suggest possible use in spreads or

'"for inclusion with other fats in specialized blends.

Paper no. J9284 in JAOes 77, 495-500 (May 2000).

Enzymatic Synthesis of t,3-Dicapryloyl-2-eicosapentaenoylglyc-erol, Roxana IrimescuQ,b, Mamoru Yasui<l, Yugo lwasakie,Nobuyoshi Shimidzub, and Tsuneo Yamane",·. al.aboramry ofMolecular Biotechnology, Graduate School of Bio- and Agro-Sciences, Nagoya University, Nagoya 464-8601, Japan, andbCentral Research Laboratory, Nippon Suisan Kaisha, Ltd., 559-6 Kitano-machi, Hachicji-shi, Tokyo 192-0906,Japan.

1,3-Dicapryloyl-2-eicosapentaenoylglycerol (CEC) was syn-thesized by interesteriflcarion of trieicosapentae.noylglycerol(EEE) with ethyl caprylate (EtC) catalyzed by LipozymeTM. Aftersome of the reaction conditions were optimized, the maximalmolar conrenr of CEC in the glycerides of the reaction mixturewas 91 %. Among the parameters studied in the optimization, thecritical ones were: (i) the water content. which influenced theconversion of EEE to CEC and 1-capryloyl-2-eicosapentaenoyl-glycerol (CEOH), and (ii) the timing of water removal underreduced pressure for the reesrerificarion of CEOH to form CEe.The complete synthesis of CEC from ethyl eicosapenraenoare(EtE) was performed in three steps: (i) hydrolysis of EtE to freeeicosapernaenoic acid (EPA), (ii) esterification of glycerol withEPA to form EEE, and (iii) inreresrenficarion of EEE with EtCunder the optimized conditions. The first fWO steps were cat-alyzed by Novoaymf and the third by Lipozyme™. The roralyield over all the steps was 88%, and no purification of the inter-mediates was necessary. The regioisomeric purity of the productwas 100% by silver-ion high-pressure liquid chromatography.

Paper no. J9400 in JAOes 77, 50·1-506 (May 2000).

Regieselecrive Analysis of the Parry Acid Composition ofTriacylglycerols with Conventional High-Performance LiquidChromatography, Jose A. Aecos«, Hugo S. Garciab, and CharlesG. Hill, jr.<I,·, QDepartment of Chemical Engineering, Universityof Wisconsin-Madison, Madison, Wisconsin 53706, andvlnsriruro Tecnol6gico de Veracruz, Veracruz 91897, Mexico.

A new method for rcgioselecrive analysis of triacylglycerolsvia conventional high-performance liquid chromatography(HPLC) has been developed. The method is simple and avoidsthe time-consuming purification processes normally characteris-tic of regioselecnve analyses. The procedure utilizes an sII-1,3-specific lipase from RI,izoplis arrhiZlls to deacylare the fatty acidresidues located at the $/1-1and $/1-3positions of triacylglycerols.The fatty acid residues esterified at the sn·2 position are deter-mined by subtraction of the results of the sst- 1,3 analysis from anoverall composition analysis based on complete saponification ofthe original sample. The fatty acid mixtures are converted to p-bromophenacyl esters and analyzed using conventional HPLCtechniques. The analytical procedure has been verified using astandard structured rriacylglycercl. The analytical results forthree edible vegetable oils are compared with those obtained viathe method proposed by P.j. Williams and co-workers.

Paper j9466 injAOes 77, 507-512 (May 2000).

Volume II • June 2000 • Inform

Abstracts

lipase-Catalyzed Synthesis of Ferulate Esters, David L.Compron"-", Joseph A. Laszlo", and Mark A. Berhow",«Biomarerials Processing Research Unit, and bBioactive AgentsResearch Unit, USDA, ARS, NCAUR, Peoria, Illinois 61604.

Four commercially available esterases were screened for theirability to esterify ferulic acid (4-hydroxy-3-methoxy cmnamare],NovozymS 435 was found to be me only one of those screenedto convert ferulic ncid rc ethyl and ceryl ferulate at 20 and 14%yields, respectively. The highest percentage conversion wasobtained using a 1:1 mole ratio of alcohol to ferulic acid instirred batch reactions in anhydrous 2-memyl-2-propanol at60°C using one equivalent (wtlwt based on ferulic acid) ofNovozym 435. Increased water content and a higheralcohoVethyl ferulare ratio had adverse effects on the lipase-car-alyzed esterification. The Novozym 435 activity was tested inless polar solvents (anhydrous toluene and hexane) by monitor-ing the alcoholysis of ethyl ferulare with l-ocranol, which result-ed in a 50% yield of ceryl ferulare. The alcoholysis was improvedto 83% by applying a 16 mm Hg vacuum for 5 min every 24 hto remove the ethanol co-product. The optimal alcoholysisparameters were applied to the alcoholysis of ethyl ferulate withmonoolein and the rransesrerificarion with triolein. The rranses-terification of ethyl ferulare with triolein in anhydrous tolueneproduced a combined 44% yield of ferulyl monoolcin and feru-lyl diolein, a 20% greater yield than that obtained for alcoholy-sis using monoolein. The highest yield, 77%, of ferulylmonoolein and ferulyl diolein was achieved using a threefoldexcess of neat triolein. The lipase-catalyzed rransesrerificarion ofethyl ferulare with triolein appears to be a technically feasibleroute to ferulyl-subsrirured acylglycerols, which are potentiallyuseful sunscreen ingredients.

Paper no. J9361 injAOes 77, 513-519 (May 2000).

Five-Factor Response Surface Optimization of the EnzymaticSynthesis of Citroncllyl Butyrntc by Lipase IM77 from Mucormiehei, Chwen-jen Shieh- and Ya-Hui Lou, Department of FoodEngineering, Da-Yeh Universiry, Da-Tsuen, Chang-Hua, 51505,Taiwan.

Response surface: methodology (RSM) and a five-level-five-factor central composite rotatable design (CCRD) were used toevaluate the effects of synthetic variables, such as reaction time(3 to 27 h), temperature {25 to 65°q, enzyme amount (10 to50%), substrate molar ratio of cirronellol to butyric acid (I: I to1:3), and added water amount (0 to 20%) on molar percent yieldof chrcnellyl butyrate by direct esterification, using lipase IM77from Mucor miehei. Reaction time and temperature were themost important variables. Substrare molar ratio had no effect onpercent molar conversion. Based on contour plots, optimal syn-thetic conditions were these: reaction time 24 h, temperature60"C, enzyme amount 20%, substrate molar ratio 1:1.5, andadded water 0%. The predicted molar conversion value was100%. An actual experimental value of 98% molar conversionwas obtained.

Paper no. J9377 in JAOes 77, 521-525 (May 2000).

Volume I I • June 2000 • Inform

Synergistic Effects of Rosemary, Sage, and Curie Acid on FattyAcid Retention of Palm Olein During Deep-fat Frying, IrwandiJaswir",b, Yaakob B. Che Mana.-, and David D. Kitrsb,Departments of «Food Technology, Universiri Putra Malaysia,43400 UPM Serdang, Selangor DE, Malaysia, and bFoodScience, University of British Columbia, Vancouver, BritishColumbia, V6T IW5 Canada.

A study 10 optimize the use of oleoresin rosemary extract,sage extract, and citric acid in refined, bleached, and deodorized(RHD) palm olein during deep-far frying of potato chips was per-formed using response surface methodology. Results showed thatthe natural antioxidants used in this study retarded oil deteriora-tion, as evidenced by retention of fatty acid profiles. The linoleicto palmitic (CI8:2JCI6:0) ratio was chosen as the parameter foroptimizing the use of natural antioxidants in RBD palm oleinduring deep-fat frying. Linoleic (R2 = 0.946) and palmitic (R2 '"0.825) acids were found to be the most important dependentvariables, giving highest R2 values to various antioxidant treat-ments after 25 h of frying. All three antioxidants had indepen-dent significant (P < 0.05) effecrs on the C18:2JCI6:0 ratio. Infact, significant effects on the C18:21 C16:0 ratio of RBD palmolein were also given by a second-order form. A combination of0.076% oleoresin rosemary extract, 0.066% sage extract, and0.037% citric acid produced the optimal retention of the essen-tial fatry acid C18:2. In addition, a synergistic effect among theseantioxidants on the fatty acid ratio of RBD palm olein wasfound.

Paper no. J9277 in JAOes 77, 527-533 (May 2000).

The Influence of Various Emulsifiers on the Partitioning andAntioxidant Activity of Hydroxybenzoic Acids and TheirDerivatives in Oil·in·Water Emulsions, Heiko Stockmartn",Karin Schwarze.", and Tuong Huynh-Bae, "Institute of HumanNutrition and Food Science, CAU University of Kiel, D-24098Kiel, Germany, and bNestie Research Center, Nestec Ltd., vers-chez-les-Bleuc, CH-'IOOOLausanne 26, Switzerland.

The partitioning behavior of a series of hydroxybenzoicacids and their derivatives was determined in biphasic warcr-oil systems, emulsifier solutions, end oil-in-water (OfW) emul-sions. The effect of gradually decreasing polarity on partition-ing behavior and antioxidant efficiency in OfW emulsions wasinvestigated by using gallic acid and its esters as antioxidants.Sodium dodecyl sulfate (5DS), ceryltrlmerhylammcnium bro-mide (CTAB), polyoxyerhylene 20 cetyl ether [Bri] 58), andpartially hydrolyzed soybean lecithin (PHLC, Emulrop<BI)wereused to investigate the influence of different classes of emulsi-fiers on the purtitioning behavior. The antioxidant acriviry ofgallic acid and its methyl, ethyl, propyl, buryl, and ceryl estersshowed markedly different trends in OIW emulsions depend-ing on the emulsifier used. The results are discussed withrespect ro the properties of the emulsifiers, such as hydrogenbond basicity, hydrophobic interactions, and structural prop-erties.

Paper J9279 in JAOes 77, 535-542 (May 2000).

Effects of Microwave and Conventional Baking on the OxidativeStabiliry and Fatty Acid Composition of Puff Pastry, OrhanDaglioglu", Murat Tasan, and Baris Tuncel, Trakya University,Tekirdag Agriculrurul Faculty, Department of Food Engineering,59100 'Ieklrdag, Turkey.

The effects of microwave and conventional baking on thefarry acid and traIlS farty acid composirions of puff pastries,which contain high amounts of hydrogenated fat, were investi-gated. In addirion, free ferry acids, peroxide value, and inductionrime for oxidative stability by the Rancimat method have beencompared for microwave- and conventionally baked puff pas-tries. The data indicate there were considerable changes in acidi-ty, peroxide value, and Rancimar induction rime in bothmicrowave- and conventionally baked samples. Although thecontent of saturated farty acids such as palmitic and stearic andthe rario of saturated to unsaturated farty acids did not changesignificantly, an apparent increase was determined in trans oleicacid levels by both baking methods. In addition, a significantdecrease in linoleic acid content of the samples was found bymicrowave baking.

Paper no. J9499 in JAOes 77, 543-545 (May 2000).

Comparison of Supercrirical Fluid and Solvent ExtractionMethods in Extracting .,..Oryzanol from Rice Bran, Zhimin Xuand J. Samuel Godber", Department of Food Science, LouisianaAgricultural Experimental Station, Louisiana State UniversityAgricultural Center, Baton Rouge, Louisiana 70803.

Organic solvents were compared with supercritical CO2 rela-tive to efficiency for extracting lipid and y-oryzanol from ricebran. A solvent mixture with 50% hexane and 50% isopropanol(vobvcl] at a temperature of 60°C for 45-60 min produced thehighest yield (1.68 mg/g of rice bran) of y-oryzanol among organ-ic solvents tested. The yield of j-orvaanct without saponificationwas approximately rwo times higher (P < 0.05) than that withsaponification during solvent extraction. However, the yield(5.39 mg/g of rice bran) of j-cryzanol in supercrirical fluidextraction under a temperature of 50°C, pressure of 68,901 kPa(680 arm), and time of 25 min was approximately four timeshigher than the highest yield of solvent extraction. Also, a highconcentration of j-oryzanol in extract (50-80%) was obtainedby collecting the extract after 15-20 min of extraction underoptimized conditions.

Paper no. J9443 in JADes 77, 547-551 (May 2000).

66'

Deacidification of Corn Oil by Solvent Extraction in a PerforatedRotating Disc Column, Carla G. Pina and Antonio J.A.Meirelles·, LASEFI Whysical Separation Laboratory), FoodEngineering Department (DEAIFEA), State University ofCampinas (UNICAMP), Sao Paulo, Brazil.

The deacidification of corn oil by continuous liquid-liquidextraction was investigated in a rcrating disc column. The sol-vent was ethanol containing approximately 6% water. The influ-ence of rotor speed, oil phase flow, and column geometry uponthe dispersed phase holdup and the mass transfer efficiency wasstudied. The dispersed phase holdup increased with the increaseof rotor speed and oil phase flow. Pratt's equation was used forcalculating the characteristic velociry. An inverse relation wasobserved between the characrerisric velocity and rotor speed,which is different from data previously reponed in the literature.The esrimated volumetric mass transfer coefficients increased asrotor speed and oil phase flow increased. The experimentalresults proved that it is feasible to obtain a refined oil with anoleic acid content less than 0.3 wt% by continuous solventextraction. They also indicated that the corresponding loss ofneutral oil was less than 5 wt%. Such value for the loss of neu-tral oil is significantly lower than the results reponed in the nr-erature for alkali or physical refining of com oil.

Paper no. J9349 in JADes 77, 553-559 (May 2000).

The Study of Epoxidized Rapeseed Oil Used as a PotentialBiodegradable Lubricant, Xuedong Wud,-, Xingang Zhang",Shengrong Yangb, Haigang Chene, and Dapu Wang<l,«School ofChemistry and Chemical Engineering, Shanghai jiaorongUniversity, Shanghai, 200240, People's Republic of China, andbLaboratory of Solid Lubrication, Lanzhou Institute of ChemicalPhysics, Chinese Academy of Science, Lanzhou, 730000, People'sRepublic of China.

The application of epoxidized rapeseed oil as a biodegradablelubricant is described. The epcxidarioo treatment has no adverseeffect on the biodegradability of the base stock. Epcxidized rape-seed oil ~HISsuperior oxidative stability compared to rapeseed oilbased on the results of both oven tests and rotary oxygen bombtests. Moreover, the oxidative stability can be dramatically pro-moted by the addition of a package of antioxidants. The epoxi-dized rapeseed oil has berrer friction-reducing and extreme pres-sure abilities according to tribological investigations. Formationof a rribopolymerization film is proposed as explanation of thetribological performance of epoxidized rapeseed oil.

Paper no. J9427 in JADes 77, 561-563 (May 2000).

Volume I t - June 2000 - Inform

Abstracts

66'

Changes in Fatty Acid Composition in Plant Tissues Expressinga Mammalian 69 Desarurase, Hangsik Moon", Jan Haaebroeke,and David F. Hildebrande- .., "Department of Agronomy,University of Kentucky, Lexington, Kentucky 40546-0091 andbPionecr Hi-Bred Inremarional, Inc., Johnston, Iowa 50131-1004.

Plant tissues expressing a mammalian stearoyl-CoA 119desat-urase were reported to accumulate 69 hexadecenoic acid (16: I),normally very minor in most plant tissues. The transgenic plantswere thoroughly analyzed for alterations of individual lipids indifferent subcellular sites. Western bIOI analysis indicated thatthe animal desarurase was targeted (0 the microsomes. The Il916:1 was incorporated into both the sn-l and sn-2 positions ofall the major membrane lipids tested, indicating that the endo-plasmic reticulum acyltransferases do not exclude unsaturatedCHi farty acids from the sn-2 position. In addition to increases inmonounsaturated and decreases in saturated farty acids, accu-mulation of 16:1 was accompanied by a reduction in 18:3 in allthe lipids tested except phosphatidylglycerol, and increases in18:2 in phospholipids. Total C16 farty acid content in the galac-rolipids of the transgenics was significantly higher than that inthe control, but those in the phospholipids were unchanged. Inrransgerucs, 611 18:1 was detected in the 5n-l position of thelipids tested except phosphatidylinositol and phosphatidylserine.Introduction of the animal desnturnse, controlled by a seed-spe-cific phaseolin promoter, into soybean somatic embryo resultedin a significant reduction in saturated fatty acids. Such effectswere greater in cotyledons than hypocoryl-radicles. This studydemonstrated that the animal desnrurase can be used to decreasethe levels of saturated fatty acids in a crop plant.

Paper no. L8357 in Lipids 35,471-479 (May 2000).

Metabolism of l-Acyl-2-0Icoyl-sn-glycero-3-pbospbo-ethanolamine in Castor Oil Iliosymhesis, jiann-Tsyh Linll,.,Karen M. Lewll,jennifer M. Chenll, Yugo Iwasakib, and ThomasA. McKeonll, UU.5. Department of Agriculture, AgriculturalResearch Service, Western Regional Research Center, Albany,California 94710, and bOepanmenr of Biological Mechanismsand Functions, Nagoya University, Nagoya 464-860 I, japan.

We have examined the role of 2-0Ieoyl-PE (pbcs-phatidylethanolamine) in the biosynthesis of triacylglycerols(TAG) by castor microsomes. In castor microsomal incubation,the label from 14C·oleare of l-palmiroyl-2-11-14CJoleoyl-sn-glyc-ero-3-phosphoethanolamine is incorporated into TAG contain-ing ricinoleate. The enzyme characteristics, such as optimal pH,and the: effect of incubation components of the oJeoyl-12-

Volume II • June 2000 • Inform

hydroxylase using 2-0Ieoyl-PE as incubation substrate are simi-lar to those for 2-01eoyl-PC (phosphatidylcholine). However,compared to 2-oleoyl-PC, 2-oleoyl-PE is a less efficient incuba-tion substrate of oleoyl-12-hydroxylase in castor microsomes.Unlike 2·01eoyl-PC, 2-oleoyl-PE is not hydroxylated to 2-ricin-oleoyl-PE by olecyl-t z-hydeoeylase and is not desarurared to 2-linoleoyl-PE by oleoyl-12-desarurase. We have demonstrated theconversion of 2-oleoyl-PE to 2-0Ieoyl-PC and vice versa. Theincorporation of label from 2-114C1oleoyl-PE into TAG occursafter its conversion ro 2-oleoyl-PC, which can then be hydroxy-lared or desarurared. We detected neither PE-N-monomethyl norPE-N,N-dimethyl, the intermediates from PE to PC by N-methyl-anon. The conversion of 2-oleoyl-PE to 2-oleoyl-PC likely occursvia hydrolysis to 1.2-diacyl-sn- glycerol by phospholipase C andthen by cholinephosphotransferase. This conversion does notappear to playa key role in driving ricinoleate into TAG.

Paper no. L8396 in Lipids 35,481-486 (May 2000).

Purification of the: Acyl-CoA Elongase Complex fromDeveloping Rapeseed and Characterization of the 3-Ketoacyl-CoA Syntbase and the: 3-Hydroxyacyl-CoA Dehydratase,Frederic Domergue", Sylvene Chevaliers, Anne Creech", C.Cassegnes, and Rene Lessireb,., «Instirure fur AllgemeineBoranik, Universirar Hamburg, 22609 Hamburg, Germany,bLaboratoire de Biogenese Membranaire. Universite VictorSegalen Bordeaux 2 (CNRS-UMR 5544), 33076 BordeauxCedex, France, and CUSTL.. UPR.E.S-ACNRS 8013 "ELICO"59655 Villeneuve d'Ascq cedex, France. '

Oleoyl-CoA elongase catalyzes four successive reactions: con-densation of malonyl-CoA to oleoyl-CoA, reduction, dehydra-tion, and another reduction. Evidence supporting this mechanismand the mcleienzymoric nature of the elongation complex arereponed. A particulate membrane fraction from rapeseed is ableto eiongarc intermediates (R,S) 3-hydroxy-20:0-CoA and (El 2,3-20:1-CoA ro very long chain fatty acids in the presence of mal-onyl-CoA. Studies of the 3-ketoacyl-CoA synthase activitiesshowed that maximal activity could be measured by using 15 to

30 j.lM 18d-CoA and 30 j.lM malonyl-CoA, and that 18:0-CoAand 18:1-CoA were the best substrates. Comparison of the con-densation and the overall elongation activities indicated that con-densation is the rate-limiting step of the elongation process. The3-hydroxyacyl-CoA dehydratase acriviry was maximal in thepresence of 75 ~M Triton X-loo and 25 j.lgof proteins. Finally,the acyl-CoA elcogase complex was solubilized and purified.During the purification process, the 3-hydroxyacyl-CoA dehy-dratase copurifled with the eloogase complex. strongly suggest-ing that rhis enzyme belongs to the elongase complex. The appar-ent molecular mass of 700 kDa determined for rhe elongase com-plex, and the fact that four different polypeptide bands weredetected after sodium dodecyl sulfate-polyacrylamide gel elec-rrophoreric analysis of the purified fraction, further suggest thatthe acyl-CoA elongase is a mulrienzym:nic complex.

Paper no. L8414 in Lipids 35, 487-494 (May 2000).

Purification and Biochemical Characterization of a NovelThermostable Lipase from Aspergillus niger, varikena M.Haridasan Namboodiri and Rajagopal Charropadhyaya ",Department of Biochemistry, Bose Institute, Calcutta 700054,India.

An extracellular 1,3·specific lipase with molecular weight of35.5 kDa and an iscelecrric point of 4.4 from Aspergilll/s nigerhas been purified 50-fold by pH precipitation followed by aseries of chromatographic steps with an overall yield of 10%.The enzyme was homogeneous as judged by denaturing poly-acrylamide gel electrophoresis and size-exclusion Iasr-perfor-mance liquid chromatography. It contained 2.8% sugar whichwas completely removed by endoglycosidase F rrearmem, and thedeglycosylated enzyme retained full activity. The native lipaseshowed optimal activity between temperatures 35 and 55"C andpH 5.0 and 6.0. The amino acid composirion and the N·terminalsequence were found to be different from lipases previously puri-fied from A. niger, The enzyme was resistant to trypsin, chy-morrypsin, endcprorease Glu-C, thrombin, and papain undernative conditions but was susceptible to cleavage by the sameproreases when heat-denatured.

Paper no. L8402 in Lipids 35, 495-502 (May 2000).

Effects of Passive Smoking on the Regulation of Rat AorticCholcstcryl Ester Hydrolases by Signal Transduction, FusakoMaehira ", Fusako Zaha, Ikuko Miyagi, Asami Tanahara, andAyano Noho, Laboratory of Biochemistry, Department of HealthTechnology, School of Health Sciences, Faculty of Medicine,Universlry of the Ryukyus, Okinawa 903-0215, Japan.

The effects of exogenous oxidative stress due to passive smok-ing on cholesteryl ester (CEl-metabolizing enzymes and their reg-ulatory kinases were examined by exposing rats to cigarettesmoke (CS) for a l-h period twice a day for 8,12, or 20 wk. Anoxidatively modified low density lipoprotein (Ox-LDL) with ahigh lipid peroxide was identified in three CS groups after allthree exposure periods. The rat aortic acid and neutral CEhydrolases (ACEH and NCEH) were activated to similar extentsby both cAMP·dependent protein kinase (PKA) and proteinkinase C (PKC) in the presence of their respective cofacrors. Theaortic PKC activity in the three CS groups exhibited significantreductions of 72, 84, and 75% as compared with the respectivecontrols, which coincided with the reductions in the ACEH activ-ities (86, 71, and 80%, respectively), whereas the PKA activitiesincreased to 121, 197, and 252% in the three CS groups, respec-tively. Reflecting the increase of the PKA activity, the NCEHactivity exhibited increases of 1l2% at 8 wk and 140% until 12wk of exposure and decreased by 50% of the control value at 20wk of exposure, suggesting inactivation ofNCEH itself. The acti-vation of acyl-Cce.cbclesrerct Q·acyltransferase activity wasassociated with an increase of free cholesterol in aorta. The vita-min E diet prevented the formation of Ox-LDL and the oxidativeinactivation of most enzymes, especially PKC, until l2 wk, butwas less effective by 20 wk. The oxidative inactivation of PKC,particularly its activated form that translocated to the membrane

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fraction, was confirmed in the in vitro exposure to active oxygengenerators at an optimal concentration; this inactivation was pre-vented by catalase and superoxide dismutase. These results sug-gested that the formation of Ox-LDL and alterations in CE-metabolizing enzymes caused by passive smoking could con-tribute to a rwofold increase in the aortic CE content, therebycontributing to one of the mechanisms for atherosclerosis associ-ated with smoking.

Paper no. L8351 in Lipids 35, 503-511 (May 2000).

Aggregation and Fusion of Vesicles Composed or N-PalmitoylDerivatives of Membrane Phospholipids, Margarita Mora,Ferran Mir, M. Africa de Madariaga, and M. Luisa Sagrisr;i·,Department of Biochemistry and Molecular Biology, Faculty ofChemistry, University of Barcelona, 08028·Barcelona, Spain.

N-Acylphosphatidylethanolamines and N-acylphosphatidyl-serines have been isolated from mammalian cells and have beenassociated with some tissue degenerative changes, although therelationship between their synthesis and the uncontrolledsequence of events that ends in irreversible tissue damage is norcompletely established. Our results show that mcnovalem anddivalent cations induce aggregation and fusion of liposomes con-srirured by N-palmitoylphosphatidylethanolamine (NPPE) andN-palmitoylphosphatidylserine (NPPS). The effectiveness ofcations to induce the aggregation of NPPE and NPPS liposomesis Cal .. > Mgh »Na-. NPPS liposomes aggregate at lower con-centrations of divalent cations than NPPE liposomes, but withsodium NPPE liposomes aggregate to a higher extern than NPPSliposomes. The reaction order for the aggregation processesdepends on the lipid and the cation nature and range from 1.04to 1.64. Dynamic light scattering shows an irreversible increaseof the size of the aggregates in the presence of all cations tested.The irreversibility of the aggregation process and the intermixingof bilayer lipids, as studied by resonance energy transfer assay,suggest that fusion, rather than aggregation, occurs. The exis-tence of a real fusion was demonstrated by the coalescence of theaqueous contents of both NPPS and NPPE liposomes in the pres-ence of either monovalent or divalent Cal ions. The different bind-ing sensitivity of Ca2.. to NPJlS and NPPE liposomes, determinedby ~ potential measurements, agrees with the results obtained inthe aggregation and fusion assays. Our results suggest that thesynthesis in vivo of N-acylated phospholipids can introduceimportant changes in membrane-mediated processes.

Paper no. L8222 in Lipids 3S, 513-524 (May 2000).

Characterization of Inositol Phospholipids and Identification ofa Mastoparan-Induced Polyphosphoinositide Response inTetrahymena pyrifonnis, George Leondaritis and DiaGalanopoulou", Department of Chemistry, University of Athens,15771 Athens, Greece.

The unicellular eukaryote Tetrahymena is a popular model forthe study of lipid metabolism. Less attention, however, has beengiven to the inositol phospholipids of the cell, although it isknown that this class of lipids plays an important role in eukary-

Volume I I • June 2000 • Inform

Abstracts

....otic cell signaling. Tetrahymena pyriformis phospharidylinosirolwas isolated, purified, and characterized by proton nuclear mag-netic resonance analysis and [2-3HJmyoinositol labeling.Labeling was also used for polyphosphoinositide (phosphatidyl-inositol phosphate and phospharidylinositol bisphcsphare] iden-tification. Tetrahymena inonrol phospholipids were found (0

belong (0 the diacylglycerol group, although major Tetrahymenaphospholipids, phosphatidy1choline and aminoethylphosphono-glycerides, have been found to be mainly alkylacylglyceroderiva-rives. Further characterization of Tetrahymena phosphatidylinos-lrol by gas chromatographic analysis indicated that 80% of farryacids were myristic acid and palmitic acid. This is also in contrastto the fatty acid profile of Tetrahymena phosphatidylcholine andphosphatidylethanolamine, with respect both to the fatty acidlength and degree of unsarurarion, and may indicate that specif-ic diacylglycerol species are connected with the phosphatidyl-inositol metabolism in this cell. Treatment of (3HJinositol-labeledTetrab)'mella cells with mastoparan, a G-protein-activaring pep-tide, induced changes in the polyphosphoinositide levels, sug-gesting that inositol phospholipids may form in Tetrahymena afunctional signaling system similar to that of higher eukaryores.Addition of 10 liM masropamn resulted in a rapid and transientincrease in [3HJphosphatidylinositol phosphate followed by adecrease in [3HJphosphatidylinositol bisphosphate. Similarchanges in lipids have been reported when phosphoinositide-phospholipase C pathway is activated in borh animal and plantcells.

Paper no. L8411 in Lipids 35, 525-532 (May 2000).

Molecular Analysis of Intact Preen Waxes of Colidris canutus(Aves: Scolopacidae) by Gas Chromatography/MassSpectrometry, Marlen H.A. Dekker", Theunis Piersmab-c, andjuap S. Sinninghe Damsres-", Departments of «MarineBiogeochemistry and Toxicology and bMarine Ecology,Netherlands Institute for Sea Research (NIOZ), Texe], TheNetherlands, and 'Centre for Ecological and EvolutionaryStudies, University of Groningen, Groningen, The Netherlands.

The intact preen wax esters of the red knot Calidris CQII/ItIlS

were studied with gas chromatography/mass spectrometry(GClMS) and GClMSIMS. In this latter technique, transitionsfrom the molecular ion to fragment ions representing the faeryacid moiety of the wax esters were measured, providing addi-tional resolution to the analysis of wax esters. The C21-CJ2 waxesters are composed of complex mixtures of hundreds of indi-vidual isomers. The odd carbon-numbered wax esters are pre-dominantly composed of even carbon-numbered u-alcchols(C14, CI6, and C18) esterified predominantly with odd carbon-numbered 2-methyl fatry acids {C7, C" CII, and CuI, resultingin relatively simple distributions. The even carbon-numberedwax esters show a far more complex distribution due to a num-ber of factors. (i) Their »-alcchcl moieties are not dominated byeven carbon-numbered e-alcohols esterified with odd carbon-numbered 2-methyl fany acids, but odd and even carbon-nom-bered e-alcohols participate in approximately equal amounts; (ii)

Volume I I ' June 2000 • Inform

odd carbon-numbered methyl-branched alcohols participateabundantly in these wax ester clusters; and (iii) with increasingmolecular weight, various isomers of rhe 2,6-, 2,8-, and 2,10·dimethyl branched fatry acids also pamcipare in the even carbon-numbered wax esters. The data demonstrate that there is a clearbiosymheric control on rhe wax ester composition although thereasons for the complex chemisrry of the waxes are not yerunderstood.

Paper no. L844 1 in Lipids 35,533-541 (May 2000).

Polyunsaturated Monoglycerides and a Pregnadiene in DefensiveGlands of the Water Beetle Agabus affrnis, Ormar Schaaf andKonrad Dermer", University of Bayreuth, Department of AnimalEcology II, 0-95440 Bayreuth, Germany.

In addition to the C21 steroid ISa-hydrOl{}'pregna-4,6-dien·3,2O-dione, four 1- or z-ecyleted polyunsaturated mcnoglyc-erides, 1- or 2·(cis-S,8,11,14-eicosarerraenoyl)glycerol and I· or2-(cis-S,8,II,14,17-eicosapentaenoyl)glycerol were identified asconstituents of the prorhcracic defensive gland secretion of thedyriscid beetle Agabus affinis by gas chromatography-mass spec-trometry of trimethylsilylated gland extracts. In a feeding assaywith minnows, synthetic samples of the rwo 2-acylated mono-glycerides showed only a weak activity as a feeding deterrent. Forthat reason, other possible functions of the monoglycerides arediscussed, such as roles as emulsifiers of cannabirnimerics.

Paper no. L8304 in Lipids 35, 543-550 (May 2000).

Lipids of Gelatinous Antarctic Zooplankton: Cnidaria andCtenophora, Matthew M. Nelsona,b,·, Charles F. Phlegere, BenO. Mooney", and Peter O. Nicholsc:.d, aDepartment of Biology,San Diego State University, San Diego, California 92182 andbDeparrmenr of Zoology, University of Tasmania, Hobart,Tasmania 7001, Australia, cCSIRO Marine Research, Hobart,Tasmania 7001, Australia, and dAntarnic CRC, Hobart,Tasmania 7001, Ausrrnlin .

Antarctic gelatinous zooplankton, including Cnidaria(Calycopsis borciJgrellinki, Diphyes antarctica, Stygiomedusagigamea, Alolla u'Yvillei, Dimophyes art:lica) and Ctenophora(Beroe cuaonis, B. forskalii, Heurobradna pileus, Bolincpslsinf"ndibltlJl/II) wert collected near Elephant Island, SouthShetland Islands, during January and February 1997 and 1998.Total lipid was low in all zooplankton (0.1-5 mg g""1wet mass)and included primarily polar lipids (59-96% of total lipid).Triacylglycerols were 0-26% of rcral lipids, and wax esters were0-1 I% in all species. Cholesterol was the major sterol in allCnidaria (50-63% of total sterols) whereas in most ctenophoresit was lower at 26-45%. These cholesterol levels are consistentwith a combined carnivorous and phytoplanktivorous diet in thectenophores, with the carnivorous diet more dominant in theCnidaria. Other sterols included primarily trans-dehydrocholes-rerol, desmosreeol, 24-methylcholest-5,22E-dien-3f)-ol, 24-nordehydrocholesterol, and 24-merhylenecholeseerol. Totalsranols were 0-6% in all zooplankton. Eicosapentaenoic acidand docosahexaenoic acid were the major polyunsarurared fany

acids (PUFA) in all samples (7-25% of total fany acids) exceptfor A. wyvillei in which docosapenraenoic acid was 10% of totalfany acids. The PUFA 18:5n-3 was nor detected in 1997 samples,but constituted 0.2-0.8% In mcsr 1998 samples.Monounsaturated fatty acids included primarily 18:1n-9c,16:ln-7c, and 18:ln-7c. The principal saturated farry acids in allsamples were 16:0, 18:0, and 14:0. These data are the firsr formany of these zooplankton species and the first sterol data formost species. The use of the signature lipid approach has enabledexamination of aspects of trophodynamics not obtainable byconventional techniques.

Paper no. L8387 in Lipids 35, 551-559 (May 2000).

Trans Fatty Acids in Adipose Tissue of french Women inRelation to Their Dietary Origins, C. Boues, N. Combes.", C.Billeaud", C. Mignerote, B. Entressangles", G. Theryd, H.Geoffriond, J.L. Brund, D. Dallard, and J.J. Lengd,OLaboratoirede Lipochlmie Alimemaire, Universlte Bordeaux I, F-33405Talence Cedex, bITERG, Laboratoire de Lipochimie Alimentaire,Universite Bordeaux I, cService de Necnetologie, anddMaternites Pellegrin, CHU Bordeaux, F-33000 Bordeaux,France.

This study reports the fatty acid composition of subcutaneousadipose tissue in French women with special emphasis on theconrenr of trans fatty acids originating from twO main dietarysources, ruminant fats and partially hydrogenated vegetable oils(PHVO). Adipose tissue trans fatty acid levels from 71 women,recruited between 1997 and 1998, were determined using a com-binarion of capillary gas chromatography and silver nitrate thin-layer chromatography. Results indicate that on average cismonounsarurares accounred for 47.9% of total fany acids, satu-rates for 32.2%, and linoleic acid for 14.4%. Cis n-3 polyunsar-urares represented only 0.7%. TOIal content of trans fatry acidswas 2.32 3:0.50%, consisting of trans 18: I (1.97 ± 0.49%), trails18:2 (0.28 ± 0.08%), and trails 16:1 (0.063: 0.03%). Trans 18:3isomers were not detectable. The level of trans fatry acids foundin adipose tissue of french women was lower than those report-ed for Canada, the United States, and Northern European coun-tries but higher than that determined in Spain. Therefore, transfatty acid consumption in France appears to be intermediatebetween that of the United Srates or North Europe and that ofSpain. Based on the equation of Enig et ai., we estimated themean daily trans 18:I acid intake of french women at 1.9 g perperson. The major trans 18: I isomer in adipose tissue was.0.1I trans, as in ruminant fats. Estimates of relative contributionof trans fany acid intake were 55% from ruminant fats and 45%from PHVO. This pattern contrasts sharply with those estab-lished for Canada and the United States where PHVO is report-ed to be the major dietary source of trans ferry acids.

Paper no. L8376 in Lipids 35, 561-566 (May 2000).

Blood Fatry Acid Composition of Pregnant and NonpregnantKorean Women: Red Cells May Act as a Reservoir ofArachidonic Acid and Docosahexeenoic Acid for Utilization by

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the Developing Fetus, K. Ghebremeskele-", Y. Min", M.A.Crawford", Joo-Hyun Namb, Ahm Kimb, ja-Nam Kooh, andHiramirsu Suzuki', slnsnrore of Brain Chemistry and HumanNutrition, The University of North London, London N7 80B,United Kingdom, bAsan Medical Centre, Department ofObstetrics and Gynaecology, College of Medicine, University ofUlsan, Seoul, South Korea, and 'National Food ResearchInstitute, Konnondai, Tsukuba, lbaraki 305-8642, Japan.

Relative fatty acid composition of plasma and red blood cell(RBG) choline phosphoglycerides (CPG), and RBC ethanolaminephosphoglycerides (EPG) of pregnant (n = 40) and nonpregnant,non lactating (II '" 40), healthy Korean women was compared.The tWOgroups were of the same ethnic origin and compamblein age and pariry. Levels of arachidonic (AA) and docosa-hexaenoic (DHA) acids were lower (l' < 0.05) and palmitic andoleic acids higher (P < 0.0001) in plasma CPG of the pregnantwomen. Similarly, the RBC crG and EPG of the pregnantwomen had lower AA and OHA (P < 0.05) and higher palmiticand oleic acids (P < 0.01). The reduction in DHA and total n-3farry acids in plasma CPG of the pregnant women was paralleledby an increase in docosarerraenoic (OTA) and docosapentaenoic(DPA) acids of the n-6 series and in OI'NDTA ratio. In the RBCphospholipids (CPG and EPG) of the pregnant women, DTA andOPA acids of the n-6 series and DPA/DTA ratio did not increasewith the decrease of the n-3 metabolites (eicosapentaenoic acid,DPA, and DHA) and total n-J. Since pregnancy was the mainidentifiable variable between the rwo groups, the lower levels ofAA and DHA in RBC CPG and EPG of the pregnant women sug-gest that rhe mothers were mobilizing membrane AA and OHAto meet the high fetal requirement for these nutrients. It may alsosuggest that RBC playa role as a potential store of AA and DHAand as a vehicle for the transport of these fatty acids from mater-nal circulation to the plncenra to be utilized by the developingfetus.

Paper no. L8318 in Lipids 35, 567-574 (May 2000).

Simultancous Derivanzenon of Acyl and S-Alkyl Moieties ofAcyl Tbioesrers by Using Trimethylsulfonium Hydroxide for GasChromatographic Analysis, Erika Klein and Nikolaus Weber·,lnsrirur fur Biochemic und Technologie der Ferre, BundesansraltfUr Getreide-, Kartoffel- und Fettforschung, 48147 Munster,Germany.

The reaction of long-chain acyl rhioesters, vh. lauric aciddodecyl rhioesrer, 1,8-di·S·palmitoyl ocmnedirhlol, and tri-stearoyl a-monothioglycerol, with trimethylsulfonium hydroxidein the presence of methanol leads to simulraneous derivarizarionof acyl moieties and S-alkyl moieties of acyl rhioesrers to the cor-responding farry acid methyl esters and methyl alkylsulfides,respectively. These denvadzed products were analyzed by gaschromatographic technique.

Paper no. L8374 in Lipids 35, 575-577 (May 2000).

Reinvestigation of Pcsiuonal Distribution of Fatty Acidsin Docosahexaenoic Acid-Rich Fish Oil Triacyl-sa-glyc-

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