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1.
The fatty acid composition of corn oil can be altered to meet consumer demand for “healthful” fats. The first step in altering the oils is to survey existing corn breeding materials for fatty acid composition. The Latin American Maize Project (LAMP), an international program designed to evaluate the agronomic characteristics of maize accessions in Latin American and U.S. germplasm banks for future use, provides useful starting materials. LAMP was based on the cooperative efforts of 12 countries. In a two-stage evaluation, the project identified the highest-yielding open-pollinated top 20% of populations, then approximately the top 5% of those 20%. Twenty of the populations from four countries with temperate climates were randomly selected for fatty acid analysis. The populations were from United States, Chile, Argentina, and Uruguay. Fifty S1 lines from each population were randomly chosen for analysis for a total of 1,000 genotypes sampled. Statistical differences in fatty acid composition were computed among the 20 populations and among the four countries. The findings showed a wide range of fatty acid profiles present in unadapted, elite corn breeding materials with ranges for each fatty acid as follows: palmitic acid, 6.3–18.2%; stearic acid, 0.9–4.5%; oleic acid, 18.5–46.1%; linoleic acid, 36.6–66.8%; linolenic acid, 0.0–2.0%; and arachidic acid, 0.0–1.4%. Several populations were significantly different from the others. Some lines had unusual fatty acid compositions, including one with 8.3% total saturates and another with 20.2% total saturates. This study shows that existing corn breeding materials could be used to produce high- and low-saturate oils, but other methods would probably be required to produce a high-oleic corn oil.  相似文献   

2.
Fatty acid composition of thirty-five Icelandic fish species   总被引:1,自引:0,他引:1  
Fat content and fatty acid composition were determined in 35 fish species caught in Icelandic waters from November 1987 to March 1988. These were not only commonly edible species, but also underutilized and less common species, in which the fatty acid composition have not been reported before. The variation int he fat content and the fatty acid composition was found to be large between and within species. The fat content and n-3 fatty acid content varies sevenfold and twentyfold, respectively. An inverse relationship was obtained between the n-3 fatty acids content and the total fat content of the fish species studied. We believe that the data reported here on 35 fish species can be useful for nutritionists and food scientists, to aid them in dietary formulation, nutrient labelling, processing and product developments, as well as for the consumers.  相似文献   

3.
Distillers corn oil (DCO), a by-product from the corn ethanol production, is an alternative source of glycerides to produce biodiesel. In the present work, this feedstock was enzymatically converted into fatty acid ethyl esters (FAEE). DCO presented relative density of 0.912 g/cm3, peroxide index of 3.05 ± 0.3 (meq/1000 g of sample) and acidity of 13.1 ± 1.96 (wt.%), with prevalence of the oleic (18:1) and linoleic (18:2) acids (sum equal to 76.9%). Three strategies were evaluated to improve the FAEE content: ethanol stepwise addition (ethanol:oil molar ratio of 4:1 (1/2 of ethanol at 0 and 1.5 h) and 3:1 (1/3 of ethanol at 0 h and 2/3 at 1.5 h or 1/3 of ethanol at 0, 1 and 2 h)); consecutive reactions (with Novozym 40086 [Rhizomucor miehei lipase] as biocatalyst); and mixture of enzymes (Novozym 40086 (6 wt.%) + Novozym 435 (Candida antarctica B lipase) (2 wt.%). The concept of combi-lipases was evaluated for the first time using this raw material, resulting in a high ester content (>96%). The higher ester yields attained with DCO, compared to refined corn oil (33%) can be related to the better solubilization of ethanol and/or glycerol by-product in the medium with DCO. The combi-lipase system kept high than 80% of this initial activity after three repeated batches of reaction. The use of DCO enables the integration of corn ethanol and biodiesel production within the same general facility, which has logistic, environmental and, economic relevance.  相似文献   

4.
As the use of tocopherols as natural antioxidants increases, it is economically and agronomically important to determine the range, composition, and factors that affect their levels in oilseed crops, a major commercial source. In this study, tocopherols were quantified from seeds of wheat, sunflower, canola, and soybean. The breeding lines analyzed possessed a broad range of economically important phenotypic traits such as disease or herbicide resistance, improved yield and agronomic characteristics, and altered storage oil fatty acid composition. Complete separation of all four native tocopherols was achieved using normal-phase high-performance liquid chromatography with ultraviolet detection. Total tocopherol concentration among wheat germ oil samples ranged from 1947 to 4082 μg g−1. Total tocopherol concentration ranges varied from 534 to 1858 μg g−1 in sunflower, 504 to 687 μg g−1 in canola, and 1205 to 2195 μg g−1 among the soybean oils surveyed. Although the composition of tocopherols varied substantially among crops, composition was stable within each crop. Total tocopherol concentration and the percentage linolenic acid were correlated positively in soybean oils with modified and unmodified fatty acid compositions. Tocopherol concentration and degree of unsaturation were not correlated in sunflower or canola seeds with genetically altered fatty acid composition. These findings suggest that breeding for altered storage oil fatty acid composition did not negatively impact tocopherol concentrations in sunflower and canola as they apparently did in soybeans. When 12 soybean breeding lines were grown at each of five locations, significant correlations were observed among planting location, breeding line, tocopherol concentration, and fatty acid composition. Analysis of seeds that matured under three different controlled temperature regimes suggests that the relationship between tocopherol concentration level and unsaturated fatty acids in commodity (not genetically modified for fatty acid composition) oil types is due to temperature effects on the biosynthesis of both compounds.  相似文献   

5.
Oil and triglyceride contents and fatty acid composition were determined for seeds in nine taxa belonging to the genusCoincya (Brassicaceae) on the Iberian Peninsula (Spain and Portugal). The oil content ranges from 11.1 to 24.6%, triglycerides from 68.7 to 88.5%. The major fatty acids were erucic (24.6–30.5%), linolenic (17.7–27.7%), linoleic (13.9–24.6%) and oleic acid (12.3–21.8%).  相似文献   

6.
The oil extracted from the fat-storage organ (fat body) of the bullfrog (Rana catesbeiana) was characterized for its fatty acid composition. The main fatty acids were palmitic (18.1%), stearic (4.1%), myristic (2.7%), oleic (31.7%), and linoleic (12.9%) acids. Long-chain polyunsaturated fatty acids were also present in significant amounts, i.e., eicosapentaenoic (1.5%) and docosahexaenoic (4.7%), and were probably derived from the fish meal content of the diet. A partially fractionated oil was extracted from the homogenized and frozen fat body with an oleic acid content of 43.2%. The natural alkaloid boldine, added at 0.5 mg/g oil level, improved the oxidative stability by a factor ranging from 1.7 to 2.4, as assessed by the Oil Stability Index method between 90 and 110°C. The stabilization effect of boldine was higher than that of naringenin, morin, and quercitin and for the synthetic antioxidant butylated hydroxytoluene at the same concentration level.  相似文献   

7.
The fatty acid compositions of flowering tops of Hypericum perforatum L. and Hypericum retusum Aucher (Guttiferae) were analyzed by gas chromatography and gas chromatography‐mass spectrometry. The major components were C16:0 (24.87%), C18:3 n‐3 (21.94%), 3‐OH‐C18:0 (18.46%) and 3‐OH‐C14:0 (14.22%) for H. perforatumL. and 3‐OH‐C14:0 (28.29%), C18:0 (16.47%) and C16:0 (14.17%) for H. retusum Aucher. Besides widespread plant fatty acids, 3‐hydroxy fatty acids, namely 3‐hydroxytetradecanoic acid (3‐OH‐C14:0) and 3‐hydroxyoctadecanoic acid (3‐OH‐C18:0) were also obtained.  相似文献   

8.
FA composition determines the quality of vegetable oil. Soybean breeders have generated and used mutations in FA genes to develop altered FA profiles in the seed. However, the expression of the alleles and the relative activity of the gene products are often dependent on the environment, and these facts have hampered the breeding efforts. To investigate the environmental effect on FA composition of soybean seed oil in specific mutant material developed at the University of Guelph, a recombinant inbred line (RIL) population was developed from a cross between a low palmitate (16∶0) line and a high-stearate (18∶0) parent. The RIL population was field-tested across three environments over 2 yr. A combined ANOVA for FA composition was conducted to determine the year and location effects on the expression of FA alleles in this material. The results indicated that linolenic (18∶3) level was most vulnerable to the environmental changes. Year effects accounted for a greater amount of variance than location effects for 16∶0, 18∶0, and 18∶1, whereas location effects were more important than year effects for the relative amounts of 18∶2 and 18∶3. Genotype × environment (year, location) interaction effects were significant for the relative amounts of all five FA according to the combined ANOVA. Our results indicated that the extreme minimum daily temperatures during September seed fill period, rather than the means or the maximum temperature, may be responsible for the ratio of saturated vs. unsaturated FA in soybean oil.  相似文献   

9.
The fatty acid selectivity of several commercial lipases was evaluated in the hydrolysis of high-erucic acid rapeseed oil (HEARO). The lipase ofPseudomonas cepacia catalyzed virtually complete hydrolysis of the oil (94–97%), while that ofGeotrichum candidum discriminated strongly against erucic acid, especially in esterification. A two-step process is suggested for obtaining a highly enriched erucic acid in which theG. candidum lipase is employed to selectively esterify the fatty acid residues of unsaturated C-18, and shorter chain acids, from a mixture of HEARO fatty acids obtained from total hydrolysis of the oil withP. cepacia lipase.  相似文献   

10.
The fatty acid composition of seeds from seven species of the genusPinus (P. pinaster, P. griffithii, P. pinea, P. koraiensis, P. sylvestris, P. mughus, andP. nigra) was established. Pine seeds are rich in oil (31–68% by weight) and contain several unusual polymethylene-interrupted unsaturated fatty acids with acis-5 ethylenic bond. These are thecis-5,cis-9 18:2,cis-5,cis-9,cis-12 18:3,cis-5,cis-11 20:2, andcis-5,cis-11,cis-14 20:3 acids, with a trace ofcis-5,cis-9,cis-12,cis-15 18:4 acid. Their percentage relative to total fatty acids varies from a low of 3.1% (P. pinea) to a high of 30.3% (P. sylvestris), depending on the species. The majorcis-5 double bond-containing acid is generally thecis-5,cis-9,cis-12 18:3 acid (pinolenic acid). In all species, linoleic acid represents approximately one-half the total fatty acids, whereas the content of oleic acid varies in the range 14–36% inversely to the sum of fatty acids containing acis-5 ethylenic bond. The easily available seeds fromP. koraiensis appear to be a good source of pinolenic acid: their oil content isca. 65%, and pinolenic represents about 15% of total fatty acids. These values appear to be rather constant.Pinus pinaster, which is grown on several thousand acres in the southwest of France, is an interesting source ofcis-5,cis-11,cis-14 20:3 acid (7% in the oil, which isca. 35% of the dehulled seed weight), an acid sharing in common three double bonds with arachidonic acid. Apparently,P. sylvestris seed oil contains the highest level ofcis-5 double bond-containing acids among pine seed oils that have ever been analyzed.  相似文献   

11.
The contents of rock lobster cephalothorax were analyzed for lipid content and fatty acid composition. They contain a diversity of saturated (35.5±0.5%), monounsaturated (26.3±1.7%), and polyunsaturated fatty acids, n-3 highly unsaturated fatty acids (11.5±0.5%) among them. The possibility of using these products as a supplement to fish and food animals’ diets is discussed.  相似文献   

12.
Simple alkyl FA esters have numerous uses, including serving as biodiesel, a fuel for compression ignition (diesel) engines. The use of acid-catalyzed esterification for the synthesis of FAME from acid oil, a by-product of edible vegetable oil refining that is produced from soapstock, was investigated. Soybean acid oil contained 59.3 wt% FFA, 28.0 wt% TAG, 4.4 wt% DAG, and less than 1% MAG. Maximum esterification occurred at 65°C and 26 h reaction at a molar ratio of total FA/methanol/sulfuric acid of 1∶15∶1.5. Residual unreacted species under these conditions, as a fraction of their content in unesterified acid oil, were FFA, 6.6%; TAG, 5.8%; and DAG, 2.6%. This corresponds to estimated concentrations of FFA, 3.2%; TAG, 1.3%; and DAG, 0.2%, on a mass basis, in the ester product. In an alternative approach, the acylglycerol species in soapstock were saponified prior to acidulation. High-acid (HA) acid oil made from this saponified soapstock had an FFA content of 96.2 wt% and no detectable TAG, DAG, or MAG. Optimal esterification conditions for HA acid oil at 65°C were a mole ratio of FFA/methanol/acid of 1∶1.8∶0.17, and 14 h incubation. FAME recovery under these conditions was 89% of theoretical, and the residual unesterified FFA content was approximately 20 mg/g. This was reduced to 3.5 mg/g, below the maximum FFA level allowed for biodiesel, by washing with NaCl, NaHCO3, and Ca(OH)2 solutions. Alternatively, by subjecting the unwashed ester layer to a second esterification, the FFA level was reduced to less than 2 mg/g. The acid value of this material exceeded the maximum allowed for biodiesel, but was reduced to an acceptable value by a brief wash with 0.5 N NaOH.  相似文献   

13.
The γ-linolenic acid (Z,Z,Z-6,9,12-octadecatrienoic acid, GLA) present in borage oil free fatty acids was concentrated in esterification reactions that were catalyzed by several preparations of the acyl-specific lipase ofGeotrichum candidum. In this manner, a 95% recovery of the GLA originally present in borage oil (25% GLA) was obtained as a highly enriched fatty acid fraction with a GLA content of >70%. Other fatty acids concentrated in this fraction were the monounsaturated fatty acids with chainlengths of C-20 and longer that were present in the oil. An immobilized preparation ofG. candidum on silica gel also was used for the enrichment of GLA in borage oil. In this instance, a 75% recovery of GLA was obtained, and the supported lipase was reusable (three cycles) with minimal loss in activity. Presented in part at the 84th Annual Meeting of the American Oil Chemists’ Society, Anaheim, California, May 1993.  相似文献   

14.
Seeds originating from some Turkish sources were analyzed with respect to their characteristics and FA compositions. These seeds represented pomegranate (Punica granatum L.), bitter grourd (Momordica charantia L.), pot marigold (Calendula officinalis L.), catalpa (Catalpa bignonoides), bourdaine (Rhamnus frangula L.), Oregon grape (Mahonia aquifolium), sarsaparilla (Smilax aspera), mahaleb (Prunus mahaleb L.), black-thorn (Prunus spinosa L.), cherry laurel (Prunus laurocerasus L.), and firethorn (Pyracantha coccinea). Bitter gourd and bourdaine seeds contain more than 20% oil. Catalpa, bourdaine, Oregon grape, blackthorn, and cherry laurel seed oil contents ranged from 15 to 20%. In the seeds from plants belonging to the Rosacea family, oil content ranged from 4.5 to 18.5%. Among the seed oils analyzed, pot marigold had one of the lowest oil contents (5.9%). Pomegranate contained the highest amount of total conjugated linolenic acid (CLNA) (86.0%). Seed oils of bitter grourd, pot marigold, mahaleb, and catalpa were rich in CLNA: 60.0, 29.5, 27.6, and 27.5%, respectively. Bourdaine, Oregon grape, and sarsaparilla seeds contained low amounts of CLNA. On the other hand, mahaleb, bourdaine, catalpa, Oregon grape, sarsaparilla, cherry laurel, blackthorn, and firethorn seed oils are basically oleic and linoleic acid-rich oils and therefore have little drying ability (semidrying oil). The results show a potential for the use of endogenous Turkish seeds as a source of CLNA.  相似文献   

15.
High concentrations of polyunsaturated fatty acids (PUFA) in meat have detrimental effects on its technical properties. The present study was carried out to investigate whether PUFA levels in pork can be reduced by increasing the concentrations of oleic acid in pig diets. To this end a bifactorial experiment was carried out with 48 female growing finishing pigs. Six different diets were used with two different concentrations of linoleic acid (12 vs. 24 g/kg) and three different concentrations of oleic acid (12 vs. 18 vs. 24 g/kg). The experiment started at a body weight (BW) of 58 kg and continued until 115 kg BW. The fatty acid composition of total lipids of backfat, perirenal fat and musculus (m.) longissimus dorsi was analysed. Concentrations of linoleic acid and total PUFA in backfat and perirenal fat were affected only by the dietary linoleic acid content but not at all by the dietary oleic acid content. Increasing the dietary concentration of oleic acid raised the level of oleic acid in those tissues at the expense of saturated fatty acids, suggesting competition between monounsaturated fatty acids and saturated fatty acids for incorporation into triglycerides. At the low dietary linoleic acid concentration, the percentages of linoleic acid and total PUFA in total lipids of m. longissimus dorsi were also unaffected by the dietary oleic acid content. In contrast, at the high dietary linoleic acid concentration, percentages of linoleic acid and total PUFA of the m. longissimus dorsi were reduced by increasing the dietary concentration of oleic acid, suggesting that oleic acid and linoleic acid compete for incorporation into muscle lipids. Thus, at high dietary linoleic acid levels the fatty acid composition of the m. longissimus dorsi was favourably affected by high dietary oleic acid concentrations; in backfat and perirenal fat, however, no beneficial effect of high dietary oleic acid levels was seen.  相似文献   

16.
Soapstock from alkaline refining of coconut oil was acidified, and the resulting acid water after neutralization was subjected to gas chromatography, electron-ionization and chemical-ionization mass spectroscopy, and high-performance liquid chromatography. The chief low-molecular weight organic components were C4−C18 fatty acids, hydroxylated acids, and sugar alcohols. The prevalence of acids and total absence of phosphate compounds make coconut acid water different in composition from the acid waters from other soapstocks.  相似文献   

17.
The increase in the population in Egypt makes it imperative to explore promising approaches to increase food supply, including protein and oil, to meet the needs of the Egyptian people. Cotton is the principal crop of Egyptian agriculture. It is grown mainly for its fiber, but cottonseed products are also of economic importance. Cottonseed is presently the main source of edible oil and meal for livestock in Egypt. Field experiments were conducted in two successive seasons at the Agricultural Research Center (Giza, Egypt) on cotton (Gossypium barbadense L. cv. Giza 75) to determine the effect of nitrogen (N) fertilizer rate (107 and 161 kg of N/ha applied as ammonium nitrate containing 33.5% N in two equal doses at 6 and 8 wk after sowing), together with foliar applications of plant growth retardants (mepiquat chloride “Pix”, chloromequat chloride “Cycocel”, and daminozide “Alar”, each applied once at 288 g active ingredient/ha, after 75 d from sowing) and zinc (Zn) (applied in chelated form after 80 and 95 d from sowing at 48 g of Zn/ha) on seed, protein and oil yields and oil properties of cotton. The higher N-rate, as well as the application of all growth retardants and Zn, resulted in an increase in cottonseed yield, seed protein content, oil and protein yields/ha, seed oil refractive index, unsaponifiable matter, and total unsaturated fatty acids (oleic and linoleic). These treatments tended to decrease oil acid value, saponification value, and total saturated fatty acids. The seed oil content tended to decrease as N-rate increased and increased with the application of all growth retardants and Zn. There were some differences between Pix, Cycocel, and Alar regarding their effects on the studied characters. The highest increase in seed, oil, and protein yields/ha was found with Pix, followed by Cycocel. The Cycocel treatment gave the lowest total saturated fatty acids oil content, followed by Alar.  相似文献   

18.
Double-fractionated palm olein (DfPOo) fractions with iodine values (IV) of 60 and 65 were each blended with low-erucic acid rapeseed (LEAR) oil in various proportions. Clarities of the blends at different temperatures were determined. Maximum levels of DfPOo-IV60 and DfPOo-IV65 in blends that remained clear at 20°C for at least 120 d were 40 and 80%, respectively. At 15°C, the maximum levels were 10 and 40%, and at 10°C, 10 and 20%, respectively. At 5°C, only a blend of 10% DfPOo-IV65 in LEAR remained clear for 120 d. Maximum levels of DfPOo-IV60 and DfPOo-IV65 in blends that passed the cold test were 30% for both palm oleins. Maximum levels of the palm oleins in blends with LEAR were higher than those of blends with soybean oil. Cloud points were lower in palm olein/LEAR blends than those of palm olein/soybean oil blends, probably because LEAR contains less saturated fatty acids than soybean oil.  相似文献   

19.
As the search for alternative sources of food to alleviate hunger continues, this study was undertaken to determine the fat content and the fatty acid composition of 15 lesser-known wild tropical seeds gathered in Nigeria. Results were contrasted with five tropical soybean varieties (Glycine max). The fat content varies from less than 1% (Pterocarpus santalinoides, Daniellia ogea) to 59% (Entandrophragma angolense). The fatty acid composition of most of the wild and mostly leguminous seeds differed considerably, compared to the composition of tropical soybeans. The oil of Adansonia digitata, Prosopis africana, Afzelia lebbeck, Enterolobium cyclocarpium, and Sesbania pachycarpa contained high proportions of linoleic and oleic acid as well as palmitic and linolenic acid. Seeds of Milletia thonningii, Lonchocarpus sericeus, and S. pachycarpa were much higher in linolenic acid and relatively poor in linoleic acid, compared to soybeans. The content of saturated fatty acids was higher than that of soybeans, resulting in lower polyunsaturated/saturated (P/S) ratios (0.83–2.12) than observed in soybeans (P/S=3.4), with the exception of the composition of S. pachycarpa (P/S=3.15). Some of these less familiar wild seeds could be used as sources for industrial or edible oils, provided that possible toxic constituents could be removed.  相似文献   

20.
The use of nondestructive analytical methods is critical for the evaluation of very small seed samples such as those from germplasm collections. The objective of this study was to evaluate the potential of near-infrared reflectance spectroscopy (NIRS) for the simultaneous analysis of seed oil content and concentration of major fatty acids in intact-seed samples of the family Brassicaceae. A total of 495 samples from 56 genera and 128 species were analyzed by NIRS. The fatty acid composition of the seed oil was determined in all the samples by gas-liquid chromatography (GLC). The total seed oil content was determined by solvent extraction in 129 samples from 22 genera. Calibration equations for oil content (n=97) and individual fatty acids (n=410) were developed and tested through external validation with the samples not included in the calibration sets. The calibration equations for oil content (r 2=0.97 in validation) and concentrations of C18:1 (r 2=0.93), C18:3 (r 2=0.95), and C22:1 (r 2=0.94) showed very good performance and provided reliable estimations of these traits in the samples of the validation set. The calibration equations for C16:0, C18:0, and C18:2 content were less reliable, with r 2 from 0.67 to 0.73. There was practically no response of NIRS to differences in C20:1 (r 2=0.31). These results demonstrated that the oil content and concentrations of C18:1, C18:3, and C22:1 can be estimated reliably within the family Brassicaceae by using NIRS calibration equations integrating broad taxonomic variability.  相似文献   

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