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Acid Composition (acid + composition)
Kinds of Acid Composition Selected AbstractsTHE ROLE OF BACTERIAL SYMBIONTS IN AMINO ACID COMPOSITION OF BLACK BEAN APHIDSINSECT SCIENCE, Issue 3 2003Xue-xia Miao Abstract To evaluate the role of bacterial symbionts (Buchnera spp.) in the black bean aphids (Aphis craccivora Koch), the aphids were treated with the antibiotic, rifampicin, to eliminate their intracellular symbiotic bacteria. Analysis of protein and amino acid concentration in 7-day-old of aposymbiotic aphids showed that the total protein content per mg fresh weight was significantly reduced by 29%, but free amino acid titers were increased by 17%. The ratio of the essential amino acids was in general only around 20% essential amino acids in phloem sap of broad bean, whereas it was 44% and 37% in symbiotic and aposymbiotic aphids, respectively, suggesting that the composition of the free amino acids was unbalanced. For example, the essential amino acid, threonine represented 21.6% of essential amino acids in symbiotic aphids, but it was only 16.7% in aposymbiotic aphids. Likewise, two nonessential amino acids, tyrosine and serine, represented 8.9% and 5.6% of total amino acids in symbiontic aphids, respectively, but they enhanced to 21.1% and 13.6% in aposymbiotic aphids. It seems likely that the elevated free amino acid concentration in aposymbiotic aphids was caused by the limited protein anabolism as the result of the unbalanced amino acid composition. [source] AMINO ACID COMPOSITION OF SOME BRAZILIAN SEAWEED SPECIESJOURNAL OF FOOD BIOCHEMISTRY, Issue 1 2000MÁRCIO VIANA RAMOS Fourteen common seaweed species from northeastern Brazil were examined for protein content and amino acid composition. Protein content varied greatly among the species, ranging from 2.30% (dry weight basis) in Corallina offlcinalis to 25.60%, in Amansia multifida. The species Amansia multifida, Caulerpa sertularioides. Enantiocladia dupcrreyi, Solieria filiformis and Vidalia obtusiloba had protein levels comparable to those of many edible legume seeds, above 18%. They showed high levels of acidic amino acids and reasonable levels of essential amino acids, with methionine being the first limiting amino acid for most of the species. The exceptions were Sargassum vulgare that had a very high content of methionine and Caulerpa sertularioides in which lysine is the first limiting amino acid and methionine the second limiting one. All species are rich in phenylalanine/tyrosine and threonine, and six are very good sources of lysine. The potential use of these species as food and/or feed is discussed. [source] FATTY ACID COMPOSITION AND CONJUGATED LINOLEIC ACID CONTENT OF COW AND GOAT CHEESES FROM NORTHWEST ARGENTINAJOURNAL OF FOOD QUALITY, Issue 3 2009CARINA P. VAN NIEUWENHOVE ABSTRACT In this study, we evaluated chemical characteristics, fatty acid composition and conjugated linoleic acid (CLA) content of cow and goat cheeses from Northwest Argentina. Similar chemical and fatty acid composition were determined in milk and cheese of both species. Palmitic, oleic and myristic acids were the most abundant fatty acids in dairy products. CLA level averaged 0.85 and 0.96 in milk and 0.76 and 1.04 g/100 g of fatty acids in cheese of cow and goat, respectively. Cis -9,trans -11 was the major isomer present in both species. Significant differences in CLA desaturase activity were observed, showing a value of 0.068 and 0.064 in milk, and 0.077 and 0.071 in cheese of cow and goats, respectively. Good nutritional properties were determined for cheeses of both species, which are fed on natural pasture during spring and summer seasons. Goat's cheese represents a higher source of CLA for human consumers than cow's cheese, offering from 156.6 to 222.6 mg/ 100 g of sample. PRACTICAL APPLICATIONS The present work shows the fatty acid composition and chemical characteristics of two fresh cheeses manufactured with cow and goat milk. Animals were fed on natural pasture during summer and spring seasons. It is known that pasture increases conjugated linoleic acid (CLA) concentration in milk fat, and the content in cheese is directly related to it. The CLA content of dairy products for the human consumers was analyzed, showing goat cheese with high polyunsaturated fatty acid content, including CLA. Cow and goat fresh cheese offer CLA as many ripening products of different countries, as cheddar or hard cheeses. Lipid composition of food is related to many illnesses, but some compounds are beneficial to human health. The main sources of CLA are milk and cheeses, and in Northwest of Argentina, no data are reported about it, where artisanal cheeses are consumed by the population. Therefore, the atherogenicity index was determined as well. [source] SEASONAL VARIATIONS IN FATTY ACID COMPOSITION OF OIL IN DEVELOPING COCONUTJOURNAL OF FOOD QUALITY, Issue 2 2009S. NARESH KUMAR ABSTRACT Studies on seasonal variation in oil and fatty acid profile of developing solid endosperm of two cultivars, West Coast Tall (WCT) and Chowghat Orange Dwarf (COD), and their hybrids indicated that oil percentage increased from 30% in 6-month-old nuts to 63% in matured nuts (12 months old). Nuts sampled during July from different levels of maturity had high oil percentage and followed by those sampled during April, October and January. During nut development to maturity, the percentages and contents of medium and long chain saturated fatty acids increased except that of palmitic and myristic acids. Concentration of long chain unsaturated fatty acids (LCUFAs) in developing coconut kernel were high at 5 and 6 months after fertilization and then decreased toward maturity. The LCUFAs were high in nuts developing during October; consequently, saturated to unsaturated fatty acid ratios were low during October. Results indicated that nuts matured during October had better nutritional quality for human consumption and those matured during January are more suitable for industrial purpose due to higher medium chain fatty acid concentrations. PRACTICAL APPLICATIONS Coconut is consumed either as the tender nut (5,6 months after fertilization) or as the kernel from mature nut (12 months after fertilization). Recent technologies of making snowball tender nut use the nuts aged 7,8 months old. Kernel also is consumed in this product. Apart from this, the coconut is being increasingly used for making different kernel-based value-added products. This information is useful, as the value-added products are being developed using different maturities of coconut. Hence, it is of paramount importance that the fatty acid profile of coconut kernel is known in detail for assessing the safety of food consumption from the human health point of view. Apart from this, information on the seasonal variation in fatty acid profile of developing endosperm gives an integrated knowledge so as to optimize the usage of coconut kernel for both human consumption and industrial exploitation. [source] AMINO ACID AND FATTY ACID COMPOSITION OF AN AQUEOUS EXTRACT OF CHANNA STRIATUS (HARUAN) THAT EXHIBITS ANTINOCICEPTIVE ACTIVITYCLINICAL AND EXPERIMENTAL PHARMACOLOGY AND PHYSIOLOGY, Issue 3 2007ZA Zakaria SUMMARY 1The present study was performed in order to determine the amino acid and fatty acid composition of an aqueous extract of the freshwater fish Channa striatus, obtained by soaking (1 : 2, w/v) fresh fillets overnight in a chloroform : methanol (2 : 1, v/v) solvent, to elucidate the mechanism responsible for its antinociceptive activity and to clarify the relationship between the presence of the amino and fatty acids and the expected activity. 2The aqueous extract was found to contain all amino acids with the major amino acids glycine, alanine, lysine, aspartic acid and proline making up 35.77 ± 0.58, 10.19 ± 1.27, 9.44 ± 0.56, 8.53 ± 1.15 and 6.86 ± 0.78% of the total protein, respectively. 3In addition, the aqueous extract was found to have a high palmitic acid (C16 : 0) content, which contributed approximately 35.93 ± 0.63% to total fatty acids. The other major fatty acids in the aqueous extract were oleic acid (C18 : 1), stearic acid (C18 : 0), linoleic acid (C18 : 2) and arachidonic acid (C20 : 4), contributing 22.96 ± 0.40, 15.31 ± 0.33, 11.45 ± 0.31 and 7.44,±,0.83% of total fatty acids, respectively. 4Furthermore, the aqueous extract was demonstrated to possess concentration-dependent antinociceptive activity, as expected, when assessed using the abdominal constriction test in mice. 5It is concluded that the aqueous extract of C. striatus contains all the important amino acids, but only some of the important fatty acids, which are suggested to play a key role in the observed antinociceptive activity of the extract, as well as in the traditionally claimed wound healing properties of the extract. [source] Environmental and Varietal Influences on the Fatty Acid Composition of Rapeseed, Soybeans and SunflowersJOURNAL OF AGRONOMY AND CROP SCIENCE, Issue 1 2010M. Werteker Abstract The fatty acid (FA) composition of oil crops is of some importance under technological as well as under nutritional aspects. The influence of temperature on this parameter in rapeseed, soybeans and sunflowers was investigated under practical agricultural conditions, whereby varietal variations were taken into account. The analysed plant material originated from variety testing trials located in different climatic zones of Austria. As a measure of the climatic conditions of a location, the mean temperature of the last 30 days before harvest was calculated. Despite the low temperature differences between the various locations, moderate but significant negative correlations between temperature and the share of linolenic (18 : 3), respectively, linoleic (18 : 2) acid on the whole quantity of FAs in rapeseed (R² = 0.18,0.42), soybeans (R² = 0.11,0.13) and sunflowers (R² = 0.15) were found. Furthermore, there was a good negative correlation in the case of sunflower seeds between temperature and oil level (R² = 0.45). The environmental influence on the share of polyunsaturated FAs differed between the different species. The results show that quality of vegetable oils is as well a question of environment as of variety. [source] Effect of Planting Date on Seed Yield, Oil Content and Fatty Acid Composition of Safflower (Carthamus tinctorius) Cultivars Grown in the Mediterranean Region of TurkeyJOURNAL OF AGRONOMY AND CROP SCIENCE, Issue 5 2003B. Samanc Abstract A study was conducted to investigate the effect of different planting dates (25 April, 5 May and 15 May 1998 and 30 April, 15 May and 25 May 1999) on the seed yield, oil content and fatty acid composition of three safflower (Carthamus tinctorius) cultivars (Yenice 5-38, Dincer 5-118 and 5-154) grown in fields of the research facility of Akdeniz University in Antalya, Turkey. While seed yield, oil content, and palmitic acid, stearic acid, and oleic acid contents decreased, linoleic acid content increased from 50.86 to 55.72 % with delay in planting date. The effect of genotype on fatty acids was greater than that of environment. [source] Fatty Acid Composition of Beef Intermuscular, Sheep Tail, Beef Kidney Fats and Its Effects on Shelf Life and Quality Properties of KavurmaJOURNAL OF FOOD SCIENCE, Issue 2 2009. Aksu ABSTRACT:, The effects of beef intermuscular (BIF), beef kidney (BKF), and sheep tail fats (STF) and storage time on fatty acid composition, the thiobarbituric acid reactive substances (TBARS), free fatty acids (FFA), pH and L*, a*, and b* values, and Enterobacteriaceae counts of sliced vacuum-packaged Kavurma were investigated. Kavurma was made from fresh beef which contained different amounts of melted BIF, BKF, STF, and salt as 10 groups. The Kavurma was sliced 3 to 4 cm thick and was vacuum packed and stored at 4 ± 0.5 °C for 360 d. Animal fat groups (BIF, STF, and BKF) had a statistically significant difference (P < 0.01) in terms of both fatty acid composition and total saturated and unsaturated fatty acids. Used animal fat types and levels in Kavurma production had a significant effect on unsaturated fatty acid composition (except for C18:1n9t) (P < 0.01). C18:1n9c was the dominant fatty acid in all Kavurma groups, and the highest C18:1n9c was determined for 50% STF + 50% BKF (group 6). TBARS and FFA values were affected by the treatment (P < 0.01) and storage time (P < 0.01). The lowest TBARS value was found in group 10 (30% BIF + 35% STF + 35% BKF). There was a significant (P < 0.01) difference in FFA content in Kavurma between 0 and 180 and 360 d, and this value increased during storage time. The a* values of Kavurma decreased during storage, and the greatest decrease was determined between days 0 and 180 of storage. Enterobacteriaceae counts were determined to be under the detectable level in all Kavurma groups during storage. [source] Volatiles and Oxidative Changes in Irradiated Pork Sausage with Different Fatty Acid Composition and Tocopherol ContentJOURNAL OF FOOD SCIENCE, Issue 2 2000C. Jo ABSTRACT: Aerobic-packaged sausage irradiated at 4.5 kGy had higher (P < 0.05) 2-thiobarbituric acid reactive substances (TBARS) than those irradiated at 0 or 2.5 kGy at 0-d storage. Generally, TBARS of aerobic- or vacuum-packaged sausage prepared with lard were higher (P < 0.05) than those of sausage prepared with flaxseed oil or corn oil. The amount of 1-heptene and 1-nonene increased (P < 0.05) with increased irradiation doses. Aldehydes, ketones, and alcohols were not influenced by irradiation at 0-d storage. However, irradiation accelerated lipid oxidation and increased the amount of aldehydes, ketones, and alcohols in aerobic-packaged sausage during storage. The tocopherol content in the sausage influenced (P < 0.05) production of volatiles at different levels of unsaturated fatty acids. [source] Effect of Rotifer Enrichment on Sunshine Bass Morone chrysops × M. saxatilis Larvae Growth and Survival and Fatty Acid CompositionJOURNAL OF THE WORLD AQUACULTURE SOCIETY, Issue 2 2008Gerald M. Ludwig The effect of enriching rotifer prey with highly unsaturated fatty acids on sunshine bass Morone chrysops × M. saxatilis larval survival and growth from ages 4 to 12 d posthatch was determined. Comparisons were made among larvae fed (1) rotifers cultured with Nannochloropsis paste versus rotifers cultured with Nannochloropsis paste and enriched with Culture Selco 3000; (2) no rotifers versus rotifers cultured with Nannochloropsis paste and enriched with Culture Selco 3000; and (3) rotifers cultured with Nannochloropsis paste and enriched with Culture Selco 3000, rotifers cultured with Nannochloropsis and Pavlova pastes and enriched with Culture Selco 3000, and rotifers cultured with Nannochloropsis paste and enriched with Culture Selco 3000 and Super Selco. The only differences in survival were unfed larvae with practically no survival compared to 55.4% survival for larvae fed rotifers cultured with paste plus Culture Selco 3000. Larvae fed rotifers cultured with paste plus Culture Selco 3000 were longer and had greater condition than those fed rotifers cultured with paste. Additional enrichment with Pavlova sp. or Super Selco had no affect. A canonical analysis of fatty acid contents of diets, rotifers, and fry supported evidence from harvest results. Distances between centroids indicated distinct differences among diets, less distinction among the rotifers, and little difference among fry. Enrichment enhanced growth, but additional enrichment beyond that done during rotifer culture did not increase survival, growth, or condition. [source] Lipid and Fatty Acid Composition of Diatoms Revisited: Rapid Wound-Activated Change of Food Quality Parameters Influences Herbivorous Copepod Reproductive SuccessCHEMBIOCHEM, Issue 10 2007Thomas Wichard Dr. Abstract Lipid and fatty acid composition are considered to be key parameters that determine the nutritive quality of phytoplankton diets for zooplanktonic herbivores. The fitness, reproduction and physiology of the grazers are influenced by these factors. The trophic transfer of lipids and fatty acids from algal cells has been typically studied by using simple extraction and quantification approaches, which, as we argue here, do not reflect the actual situation in the plankton. We show that cell disruption, as it occurs during a predator's grazing on diatoms can drastically change the lipid and fatty acid content of the food. In some algae, a rapid depletion of polyunsaturated fatty acids (PUFAs) is observed within the first minutes after cell disruption. This fatty acid depletion is directly linked to the production of PUFA-derived polyunsaturated aldehydes (PUA); these are molecules that are thought to be involved in the chemical defence of the algae. PUA-releasing diatoms are even capable of transforming lipids from other sources if these are available in the vicinity of the wounded cells. Fluorescent staining reveals that the enzymes involved in lipid transformation are active in the foregut of copepods, and therefore link the depletion processes directly to food uptake. Incubation experiments with the calanoid copepod Temora longicornis showed that PUFA depletion in PUA-producing diatoms is correlated to reduced hatching success, and can be compensated for by externally added single fatty acids. [source] Natural vegetable fats in the prevention of irritant contact dermatitisCONTACT DERMATITIS, Issue 1 2002S. Schliemann-Willers Chronic irritant contact dermatitis (ICD) is one of the most pressing problems in occupational medicine and is common in the food processing industry. To date, protective creams that fulfil the special requirements in the foodstuffs industry have not been available. Therefore, we studied the efficacy of pre-exposure application of natural vegetable fats in the prevention of experimentally induced ICD. A panel of 20 healthy volunteers was tested with a repetitive irritation test using sodium lauryl sulfate (SLS) as a standard irritant in a randomized study. Application sites were assessed clinically and by the use of bioengineering techniques (evaporimetry, chromametry, and corneometry). Rape seed and palm fats showed significant protective potential. Gas-chromatographic analysis revealed differences in the fatty acid composition of the vegetable. Higher content of linoleic acid and lower content of oleic acid was associated with beneficial effects. Our results are a new approach in the prevention of ICD and towards the development of new protective preparations for workplaces in the foodstuffs industry. [source] Analysis of ,-globulin mobility on routine clinical CE equipment: Exploring its molecular basis and potential clinical utilityELECTROPHORESIS, Issue 15 2009Dieter Vanderschaeghe Abstract A study was conducted on the variability of ,-globulin mobility in serum protein electrophoresis and its molecular basis. We found that the migration time of ,-globulins can be reproducibly determined (CV=1.1%) on clinical CE equipment. Moreover, we found a significant difference (p<0.001) in the migration of ,-globulins between chronic liver disease patients (n=98) and a healthy reference group (n=47). Serum immunoglobulins were purified from these patients' sera using protein L -agarose and their glycosylation was studied using CE on a DNA sequencer. This glycomics approach revealed that several non-sialylated N-glycans show a moderate Pearson correlation coefficient (r=0.2,0.4) with the migration time of ,-globulins. Their sialylated structures correlate negatively (r=,0.2 to ,0.3). Immunoglobulins are significantly more sialylated in the healthy reference group compared with the patients (p<0.001). We estimated that sialylation heterogeneity contributes about 36% to the molecular variance (carbohydrates and amino acid composition) that affects the electrophoretic mobility of immunoglobulins. This is the first report on the migration time of ,-globulins on a clinical CE instrument and its potential clinical value to the routinely analyzed serum protein CE profiles. [source] Determination of amino acids in rat vitreous perfusates by capillary electrophoresisELECTROPHORESIS, Issue 17 2004Kongthong Thongkhao-On Abstract In vivo determinations of amino acids are important for improving our understanding of physiological states of biological tissue function and dysfunction. However, the chemically complex matrix of different biological fluids complicates the assay of this important class of molecules. We introduce a method for characterizing the amino acid composition of submicroliter volumes of vitreous humor perfusates. Low-flow push-pull perfusion sampling is compatible with collecting small volume samples in a complicated matrix that are potentially difficult to separate. An efficient, sensitive, and rapid analysis of amino acids from in vivo perfusates of the vitreous is presented with 3-(4-carboxybenzoyl)-2-quinoline-carboxaldehyde (CBQCA) derivatitation and capillary electrophoresis (CE) separation with laser-induced fluorescence detection (LIF). Derivatization with CBQCA for up to 2 h provided high sensitivity and low detection limits at the nM level. Seventeen amino acids including D -serine (D -Ser) and D -aspartate (D -Asp) were resolved in less than 10 min. Importantly, D -Ser is separated from its enantiomeric pair. Characterization of vitreal amino acids with this assay technique will be useful for understanding ocular diseases and physiological mechanisms in vision. [source] Supercritical fluid extraction of lipids from the heterotrophic microalga Crypthecodinium cohniiENGINEERING IN LIFE SCIENCES (ELECTRONIC), Issue 2 2010Ricardo Miguel Couto Abstract Microalgae biomass can be a feasible source of ,-3 fatty acids due to its stable and reliable composition. In the present study, the Crypthecodinium cohnii growth and docosahexaenoic acid (DHA, 22:6,3) production in a 100,L glucose-fed batch fermentation was evaluated. The lipid compounds were extracted by supercritical carbon dioxide (SC-CO2) from C. cohnii CCMP 316 biomas, was and their fatty acid composition was analysed. Supercritical fluid extraction runs were performed at temperatures of 313 and 323,K and pressures of 20.0, 25.0 and 30.0,MPa. The optimum extraction conditions were found to be 30.0,MPa and 323,K. Under those conditions, almost 50% of the total oil contained in the raw material was extracted after 3,h and the DHA composition attained 72%,w/w of total fatty acids. The high DHA percentage of total fatty acids obtained by SC-CO2 suggested that this extraction method may be suitable for the production of C. cohnii value added products directed towards pharmaceutical purposes. Furthermore, the fatty acid composition of the remaining lipid fraction from the residual biomass with lower content in polyunsaturated fatty acids could be adequate for further uses as feedstock for biodiesel, contributing to the economy of the overall process suggesting an integrated biorefinery approach. [source] Effects of maternally transferred organochlorine contaminants on early life survival in a freshwater fishENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 10 2005Thomas A. Johnston Abstract Laboratory research has shown that female fish can pass toxic organochlorines (OCs) from their bodies to their eggs, killing their offspring if sufficient quantities are transferred. We conducted a controlled incubation study using gametes from a wild, OC-contaminated walleye (Sander vitreus) population (Bay of Quinte, Lake Ontario, Canada) in order to assess among-female variation in offspring early life survival in relation to ova concentrations of planar OCs (polychlorinated dibenzo- p -dioxins and furans and planar polychlorinated biphenyls) and a suite of other maternal and ova characteristics. Equal volumes of ova from each female were fertilized, pooled, and incubated together as an experimental cohort. Relative survival of each female's offspring was estimated as the proportion of surviving larvae (at ,5 d posthatch) that she contributed to the cohort as determined by microsatellite DNA parentage assignment. Total planar OC concentration (expressed as toxic equivalency of 2,3,7,8-tetrachloro-dibenzo- p -dioxin) of ova was positively related to maternal age and size and to ova lipid content. However, early life survival did not decline with increasing ova planar OC concentrations. Similarly, we observed no significant relationships between early life survival and ova thiamine content, ova fatty acid composition, or maternal age or size. Early life survival was more strongly correlated with date of spawn collection, thyroid hormone status of the ova, and ovum size. Maternally transferred planar OCs do not appear to negatively influence female reproductive success in this walleye population. [source] Does the Giant Wood Spider Nephila pilipes Respond to Prey Variation by Altering Web or Silk Properties?ETHOLOGY, Issue 4 2007I-Min Tso Recent studies demonstrated that orb-weaving spiders may alter web architectures, the amount of silk in webs, or the protein composition of silks in response to variation in amount or type of prey. In this study, we conducted food manipulations to examine three mechanisms by which orb-weaving spiders may adjust the performance of webs to variation in prey by altering the architectures of webs, making structural changes to the diameters of silk threads, and manipulating the material properties or amino acid composition of silk fibers. We fed Nephila pilipes two different types of prey, crickets or flies, and then compared orb structure and the chemical and physical properties of major ampullate (MA) silk between groups. Prey type did not affect orb structures in N. pilipes, except for mesh size. However, MA silk diameter and the stiffness of orbs constructed by spiders fed crickets were significantly greater than for the fly group. MA fibers forcibly silked from N. pilipes fed crickets was significantly thicker, but less stiff, than silk from spiders fed flies. Spiders in the cricket treatment also produced MA silk with slightly, but statistically significantly, more serine than silk from spiders in the fly treatment. Percentages of other major amino acids (proline, glycine, and glutamine) did not differ between treatments. This study demonstrated that orb-weaving spiders can simultaneously alter some structural and material properties of MA silk, as well as the physical characteristics of webs, in response to different types of prey. [source] Postprandial lipemic response to alpha-linolenic acid rich oil, butter, and olive oilEUROPEAN JOURNAL OF LIPID SCIENCE AND TECHNOLOGY, Issue 9 2010Julia Svensson Abstract Postprandial lipemia varies with composition of dietary fat due to partitioning of fatty acids between ,-oxidation, incorporation into TAG, and tissue lipids. Effects of alpha-linolenic acid (ALA) are poorly characterized. Lipase-catalyzed transesterification was used to produce a novel ALA-oil (35% ALA) from rapeseed and linseed oil. We hypothesized a lower postprandial lipemic response with ALA-oil than with olive oil and butter due to higher ,-oxidation of ALA. A randomized crossover study with 26 healthy men compared the effects on plasma lipids 7,h after a breakfast containing 35,g ALA-rich oil, butter fat, or olive oil. The incremental area under curve for plasma TAG was lower with butter than with olive oil (34%, p<0.05) and ALA-oil (25%, ns). After ALA-oil percentage ALA increased, in TAG to a constant level of 7,mol% and in NEFA to 6% after 7,h. Since total NEFA increased with time the amount of exogenous ALA in NEFA also increased. Butter resulted in lower postprandial lipemia than the oils, the difference exceeding what is expected from the presence of short and medium chain fatty acids in butter. There was a considerable recirculation of ALA into the NEFA pool available for oxidation. Practical application: Enzymatic transesterification was used to produce a dietary oil rich in ALA. By randomizing the partitioning of ALA more evenly between the TAG molecules the risk of oxidation could be reduced. Analyses showed that the ALA-oil was stable during storage for at least 3 months. Enzymatic transesterification could be used as an advantageous method to design an ALA rich dietary oil with new properties regarding fatty acid composition, susceptibility to oxidation, and effects on blood lipids. [source] Comparative analysis of triacylglycerols from Olea europaea L. fruits using HPLC and MALDI-TOFMSEUROPEAN JOURNAL OF LIPID SCIENCE AND TECHNOLOGY, Issue 5 2010Faouzi Sakouhi Abstract MALDI-TOFMS and HPLC are two analytical methods that were used to characterize triacylglycerols (TAG) of the Meski, Sayali, and Picholine Tunisian olive varieties. The HPLC chromatograms of the oils showed the presence of 15 TAG species, among which triolein (OOO) was the most abundant (21,48%). In the Sayali cultivar, OOO was the predominant TAG species followed by POO and LOO. However, the minor TAG molecules were represented by LnLO and LnLP. MALDI mass spectra produced sodiated ([M,+,Na]+) and potassiated ([M,+,K]+) TAG molecules; only the major TAG were potassiated [OOO,+,K] ([OOO,+,K]+, [POO,+,K]+, and [LOO,+,K]+). In contrast to the HPLC chromatograms, the MALDI mass spectra showed 13 peaks of TAG. The major peak was detected at m/z,907, which corresponds to OOO with an Na+ adduct. The results from both HPLC and MALDI techniques predict the fatty acid composition and their percentages for each olive variety. Practical applications: TAG are the main components in vegetable oils. These biomolecules determine the physical, chemical, and nutritional properties of the oils. The nutritional benefits of TAG are related to DAG (moderate plasma lipid level) and esterified FA, which are intermediate biosynthetic molecules of TAG. TAG analysis is necessary to discriminate between oils of different origin, since some oils have similar FA profiles. Olive products, oils, and table olives, are the main diet sources of TAG in the Mediterranean countries. In this work, chromatographic and spectrometric methods were used for TAG analysis and characterization of Tunisian olive varieties. [source] Commercial Runner peanut cultivars in the USA: Fatty acid compositionEUROPEAN JOURNAL OF LIPID SCIENCE AND TECHNOLOGY, Issue 2 2010Eui-Cheol Shin Abstract Though peanuts are classified as a high-fat food, they possess good proportions of fatty acids deemed as heart healthy. The fatty acid compositions of Runner peanuts were determined for commercially grown cultivars over two recent crop years. GC-FID analyses revealed that the fatty acid levels for Runner peanuts were significantly (p,<0.05) different among the normal, mid-, and high-oleic peanuts investigated. Oleic acid-to-linoleic acid (O/L) ratios were found to be 1.93,±,0.30, 5.25,±,1.12, and 16.9,±,5.20 for normal, mid-, and high-oleic peanut lipids, respectively. Tamrun OL01 possessed a fatty acid profile characteristic of a mid-oleic cultivar. From the sample set (n,=,151), mean %,weights for oleic acid and linoleic acid were 52.09,±,2.84 and 27.38,±,2.60 in normal, 69.33,±,3.18 and 13.66,±,2.35 in mid-oleic, and 78.45,±,2.05 and 5.11,±,1.67 in high-oleic peanuts, respectively. Cluster analysis segregated cultivars based on fatty acids into normal, mid-, and high-oleic groups. Factorial analysis revealed that cultivar effects were significant (p,<0.01) for all fatty acids, except for lignoceric acid. Cultivar effects were also highly significant (p,<0.001) for O/L, IV, unsaturated/saturated fatty acid (U/S) ratio, and %,saturation. Significant crop year effects were shown for palmitic, oleic, arachidic, gondoic, and lignoceric acids, as well as U/S ratio and %,saturation. Healthy unsaturated fats accounted for ,80% in all crop years and cultivars. [source] Physical-chemical characteristics and oxidative stability of oil obtained from lyophilized raspberry seedEUROPEAN JOURNAL OF LIPID SCIENCE AND TECHNOLOGY, Issue 11 2009Aleksandra, urovi Abstract Fresh raspberry (Rubus idaeus), cultivar Willamette, was freeze-dried (lyophilization). A byproduct of lyophilization is "fine dust" of raspberry consisting of finely ground raspberry fruit body and seed. The seeds were separated. The seed oil was isolated and its physical and chemical characteristics were determined. Parameters that characterize the seed and quality of the oil were examined, including fatty acid composition, oxidative stability under different storage conditions, and radical-scavenging activity. The fatty acid composition was determined by GC/FID and the contents of the dominant fatty acids were found as: oleic 16.92%, linoleic 54.95%, and ,-linolenic acid 23.97%. The oxidative stability of the oil was poor. The induction period by Rancimat test at 100,°C was 5.2,h. The radical-scavenging activity is similar to that of resveratrol [1,3-benzenediol 5-(1E -2-4-hydroxy-phenyl-ethyl)]. Although this product is used in the candy industry, it would be far more useful if raspberry oil of satisfactory quality could be extracted. This paper demonstrates that sifted lyophilized seeds can be used for the extraction of oils. This process allows for maximal usage of the byproducts, reduces losses and it increases the development of new products. [source] Fatty acid composition of selected roes from some marine speciesEUROPEAN JOURNAL OF LIPID SCIENCE AND TECHNOLOGY, Issue 9 2009Miguel Ángel Rincón-Cervera Abstract Fifteen roes from different marine fish species available in Spain were analyzed in order to determine their fatty acid (FA) composition, especially the eicosapentaenoic acid (20:5n -3, EPA) and docosahexaenoic acid (22:6n -3, DHA) contents. Roes from Atlantic bonito (Sarda sarda), European squid (Loligo vulgaris), cuttlefish (Sepia spp.), lumpfish (Cyclopterus lumpus), European hake (Merluccius merluccius), Atlantic salmon (Salmo salar) and gonads of male Atlantic mackerel (Scomber scombrus) reached EPA + DHA amounts higher than 30% of the total FA, and among them, roes from lumpfish, European hake and salmon provide different FA type ratios that could make them adequate as dietary sources of EPA and DHA. [source] Characterization of volatile compounds and triacylglycerol profiles of nut oils using SPME-GC-MS and MALDI-TOF-MSEUROPEAN JOURNAL OF LIPID SCIENCE AND TECHNOLOGY, Issue 2 2009Stefanie Bail Abstract Several nut oil varieties mainly used as culinary and overall healthy food ingredients were subject of the present study. Headspace solid-phase microextraction combined with gas chromatography-mass spectrometry was employed in order to determine the qualitative composition of volatile compounds. Furthermore, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry was used in order to assess the profiles and relative composition of the prevalent triacylglycerols (TAG) within the oils. The headspace of the majority of oil samples was dominated by high contents of acetic acid (up to 42%) and hexanal (up to 32%). As nut oils are typically gained by cold-pressing from previously roasted nuts, characteristic pyrazine derivatives as well as degradation products of long-chain fatty acids were detected. TAG analysis of these oils revealed a quite homogeneous composition dominated by components of the C52 and C54 group composed mainly of oleic (18:1), linoleic (18:2), stearic (18:0) and palmitic (16:0) acid residues representing together between 65 and 95% of the investigated nut oils. The TAG profiles showed characteristic patterns which can be used as ,fingerprints' of the genuine oils. Nut oils exhibiting quite similar fatty acid composition (e.g. hazelnut, pistachio and beech oil) could be clearly discriminated based on TAG showing significant differences between the oils. [source] Fatty acid composition in wild and cultivated pacu and pintado fishEUROPEAN JOURNAL OF LIPID SCIENCE AND TECHNOLOGY, Issue 2 2009Augusto Tanamati Abstract The fatty acid compositions of muscle tissue taken from wild strains of pintado (Pseudoplatystoma corruscans) and pacu (Piaractus mesopotamicus) fish, which were taken from the Brazilian Pantanal, were compared to the fatty acid compositions of tissue taken from two corresponding cultivated strains, which were fed commercial diets. The cultivated species possessed lipid contents of 12.2% (pacu) and 8.9% (pintado) while the wild species contained 7.9% (pacu) and 2.5% (pintado) lipids. Despite the high lipid contents of the cultivated pintado and pacu, the n -3 polyunsaturated fatty acid concentrations in muscle tissue were higher in wild pintado (224.9,mg/g flesh) and wild pacu (485.1,mg/g flesh) than in their respective cultivated strains (129.8 and 106.1,mg/g flesh, respectively). The n -6/n -3 ratios of pacu were 1.2 (wild) and 9.8 (cultivated), and those of pintado were 1.0 (wild) and 7.3 (cultivated). The fatty acid composition of pacu and pintado are strongly influenced by habitat and diet. [source] Supplemental dietary flaxseed oil affects both neutral and phospholipid fatty acids in cultured tilapiaEUROPEAN JOURNAL OF LIPID SCIENCE AND TECHNOLOGY, Issue 8 2008Nilson E. de Souza Abstract This work aimed to evaluate the neutral lipid (NL) and phospholipid (PL) classes in tilapia (Oreochromis niloticus) muscle tissue. Tilapias were raised in captivity for a period of 5,months with increasing levels (0, 1.25, 2.50, 3.75, and 5.00%) of flaxseed oil [source of ,-linolenic acid (LNA), 18:3n -3] in substitution for sunflower oil (control). The NL/PL ratio was 1.9, and 45,fatty acids were determined for both classes of lipid. The class totals of n -3 acids always increased in all treatments, while the totals for n -6 acids always decreased (p,<0.05). For a given level of flaxseed oil, the LNA contents were consistently higher, including EPA (20:5n -3) and DHA (22:6n -3). Arachidonic acid (20:4n -6) remained high in the PL but was reduced as levels of dietary flaxseed oil were increased. The n -6/n -3 ratios decreased significantly with the rise in flaxseed oil content in all treatments, and highly unsaturated fatty acid contents increased with the levels of flaxseed oil. Overall, the influence of flaxseed oil on the fatty acid composition in the contributing NL and PL classes was to increase n -3 PUFA, thus raising the nutritional value of this freshwater fish meat and, consequently, contributing to the health of consumers. [source] Thermostability of genetically modified sunflower oils differing in fatty acid and tocopherol compositionsEUROPEAN JOURNAL OF LIPID SCIENCE AND TECHNOLOGY, Issue 8 2008Susana Marmesat Abstract The objective of the study was to investigate the performance at frying temperature of a new sunflower oil with high content of oleic and palmitic acid (HOHPSO) and containing ,-tocopherol as the most abundant natural antioxidant. HOHPSO either containing ,- or ,-tocopherol (HOHPSO-, and HOHPSO-,, respectively) were obtained from genetically modified sunflower seeds and refined under identical conditions. The oil stability against oxidation, as measured by Rancimat at 120,°C, was much higher for the oil containing ,-tocopherol, suggesting the higher effectiveness of ,-tocopherol as compared to ,-tocopherol to delay oxidation. Experiments at high temperature (180,°C) simulating the conditions applied in the frying process clearly demonstrated that, for the same periods of heating, the oil degradation and the loss of natural tocopherol were significantly lower for the oil containing ,-tocopherol. Comparison of different genetically modified sunflower oils with different fatty acid compositions confirmed that oil degradation depended on the fatty acid composition, being higher at a higher degree of unsaturation. However, the loss of tocopherol for a similar level of oil degradation was higher as the degree of unsaturation decreased. Overall, the results showed that HOHPSO-, had a very high stability at frying temperatures and that mixtures of HOHPSO-, and HOHPSO-, would be an excellent alternative to fulfill the frying performance required by the processors and the vitamin,E content claimed by the consumers. [source] Seed roasting improves the oxidative stability of canola (B.,napus) and mustard (B.,juncea) seed oilsEUROPEAN JOURNAL OF LIPID SCIENCE AND TECHNOLOGY, Issue 4 2008Chakra Wijesundera Abstract Animal fats and partially hydrogenated vegetable oils (PHVO) have preferentially been used for deep-frying of food because of their relatively high oxidative stability compared to natural vegetable oils. However, animal fats and PHVO are abundant sources of saturated fatty acids and trans fatty acids, respectively, both of which are detrimental to human health. Canola (Brassica napus) is the primary oilseed crop currently grown in Australia. Canola quality Indian mustard (Brassica juncea) is also being developed for cultivation in hot and low-rainfall areas of the country where canola does not perform well. A major impediment to using these oils for deep-frying is their relatively high susceptibility to oxidation, and so any processing interventions that would improve the oxidative stability would increase their prospects of use in commercial deep-frying. The oxidative stability of both B.,napus and B.,juncea crude oils can be improved dramatically by roasting the seeds (165,°C, 5,min) prior to oil extraction. Roasting did not alter the fatty acid composition or the tocopherol content of the oils. The enhanced oxidative stability of the oil, solvent-extracted from roasted seeds, is probably due to 2,6-dimethoxy-4-vinylphenol produced by thermal decarboxylation of the sinapic acid naturally occurring in the canola seed. [source] Effects of hydrogenation parameters on trans isomer formation, selectivity and melting properties of fatEUROPEAN JOURNAL OF LIPID SCIENCE AND TECHNOLOGY, Issue 3 2008Anar Musavi Abstract Effects of hydrogenation conditions (temperature, hydrogen pressure, stirring rate) on trans fatty acid formation, selectivity and melting behavior of fat were investigated. To this aim, soybean oil was hydrogenated under various conditions and fatty acid composition, trans isomer formation, slip melting point (SMP), solid fat content (SFC) and iodine number (IV) of the samples withdrawn at certain intervals of the reactions were monitored. A constant ratio (0.03%) of Nysosel 222 was used in the various combinations of temperature (150, 165 and 180,°C), stirring speed (500, 750 and 1000,rpm) and hydrogen pressure (1, 2 and 3,bar). Raising the temperature increased the formation of fatty acid isomers, whereas higher stirring rates decreased this formation, while changes in hydrogen pressure had no effect or slightly reduced it, depending on other parameters. Results also indicated that the trans fatty acid ratio increased with IV reduction, reached the highest value when the IV was about 70 and decreased at IV < 70 due to saturation. Selectivity values (S21) at that point ranged between 5.78 and 11.59. Lower temperatures and higher stirring rates decreased not only the trans isomer content but also the S21 values at significant levels. However, same effects were not observed with the changes in hydrogen pressure. It was determined that a high SMP does not necessarily mean a high SFC. Selective conditions produced samples with higher SFC but lower SMP, which is possibly because of higher trans isomer formation as well as lower saturation. [source] Unusual stability of human neuroglobin at low pH , molecular mechanisms and biological significanceFEBS JOURNAL, Issue 23 2009Paola Picotti Neuroglobin (Ngb) is a recently discovered globin that is predominantly expressed in the brain, retina and other nerve tissues of human and other vertebrates. Ngb has been shown to act as a neuroprotective factor, promoting neuronal survival in conditions of hypoxic,ischemic insult, such as those occurring during stroke. In this work, the conformational and functional stability of Ngb at acidic pH was analyzed, and the results were compared to those obtained with Mb. It was shown by spectroscopic and biochemical (limited proteolysis) techniques that, at pH 2.0, apoNgb is a folded and rigid protein, retaining most of the structural features that the protein displays at neutral pH. Conversely, apoMb, under the same experimental conditions of acidic pH, is essentially a random coil polypeptide. Urea-mediated denaturation studies revealed that the stability displayed by apoNgb at pH 2.0 is very similar to that of Mb at pH 7.0. Ngb also shows enhanced functional stability as compared with Mb, being capable of heme binding over a more acidic pH range than Mb. Furthermore, Ngb reversibly binds oxygen at acidic pH, with an affinity that increases as the pH is decreased. It is proposed that the acid-stable fold of Ngb depends on the particular amino acid composition of the protein polypeptide chain. The functional stability at low pH displayed by Ngb was instead shown to be related to hexacoordination of the heme group. The biological implications of the unusual acid resistance of the folding and function of Ngb are discussed. [source] Multifunctional host defense peptides: intracellular-targeting antimicrobial peptidesFEBS JOURNAL, Issue 22 2009Pierre Nicolas There is widespread acceptance that cationic antimicrobial peptides, apart from their membrane-permeabilizing/disrupting properties, also operate through interactions with intracellular targets, or disruption of key cellular processes. Examples of intracellular activity include inhibition of DNA and protein synthesis, inhibition of chaperone-assisted protein folding and enzymatic activity, and inhibition of cytoplasmic membrane septum formation and cell wall synthesis. The purpose of this minireview is to question some widely held views about intracellular-targeting antimicrobial peptides. In particular, I focus on the relative contributions of intracellular targeting and membrane disruption to the overall killing strategy of antimicrobial peptides, as well as on mechanisms whereby some peptides are able to translocate spontaneously across the plasma membrane. Currently, there are no more than three peptides that have been convincingly demonstrated to enter microbial cells without the involvement of stereospecific interactions with a receptor/docking molecule and, once in the cell, to interfere with cellular functions. From the limited data currently available, it seems unlikely that this property, which is isolated in particular peptide families, is also shared by the hundreds of naturally occurring antimicrobial peptides that differ in length, amino acid composition, sequence, hydrophobicity, amphipathicity, and membrane-bound conformation. Microbial cell entry and/or membrane damage associated with membrane phase/transient pore or long-lived transitions could be a feature common to intracellular-targeting antimicrobial peptides and mammalian cell-penetrating peptides that have an overrepresentation of one or two amino acids, i.e. Trp and Pro, His, or Arg. Differences in membrane lipid composition, as well as differential lipid recruitment by peptides, may provide a basis for microbial cell killing on one hand, and mammalian cell passage on the other. [source] | ||||||||||||||||||||||||||||||||||||||||