Effect of high fat corn oil,olive oil and fish oil on phospholipid fatty acid composition in male F344 rats

Epidemiological and laboratory animal model studies have provided evidence that the effect of dietary fat on colon tumorigenesis depends on the amount of fat and its composition. Because of the importance of the composition of dietary fat and of tissue membrane fatty acid composition in tumor promotion, experiments were designed to investigate the relative effects of high fat diets rich in ω3, ω6 and ω9 fatty acids and colon carcinogen on the phospholipid fatty acid composition of liver, colon, small intestine, erythrocytes and blood plasma. At 6 wk of age, groups of animals were fed diets containing 5% corn oil (LFCO), 23.5% corn oil (HFCO), 23.5% olive oil (HFOO), and 20.5% fish oil plus 3% corn oil (HFFO). Two weeks later all the animals except the vehicle-treated animals received azoxymethanes.c. once weekly for 2 wk at a dose rate of 15 mg/kg body weight. Animals were sacrificed 5 d later and liver, colon, small intestine and erythrocytes and blood plasma were analyzed for phospholipid fatty acids. The results indicate that the phospholipid fatty acid composition of liver, colon and small intestine of HFCO diet fed animals, were not significantly different from those fed the LFCO diet. The levels of palmitoleic acid and linoleic acid were increased in erythrocytes and blood plasma of the animals fed the HFCO diet compared to those fed the LFCO diet. Feeding the HFCO diet significantly increased the oleic acid content and decreased the linoleic acid and arachidonic acid levels in various organs when compared to the HFCO diet. Animals fed the HFFO diet showed a marked increase in eicosapentaenoic acid and docosahexaenoic acid and a decrease in linoleic acid and arachidonic acid levels as compared to those fed the HFCO diet. The results also indicate that carcinogen treatment had only a minimal effect on the phospholipid fatty acid composition.     

Improving the fatty acid composition of corn oil by using germplasm introgression

The general public has shown increasing interest in consuming oils that are beneficial to health. Thus, oil from corn (Zea mays L.), along with most major edible oils, has been the target of genetic alterations to improve the fatty acid composition. The fatty acid profile goals vary, depending upon the intended use for the oil. We have targeted the development of corn oil with 1) low total saturated fatty acids, 2) high total saturated fatty acids, and 3) mid‐oleic acid, in each case via two different sources: exotic germplasm identified through an international program to broaden the corn germplasm base and introgression of a wild, grassy relative of corn, Tripsacum (Tripsacum dactaloides L). We have been successful at identifying corn lines with each of the noted traits.     

Effect of altered fatty acid composition on soybean oil stability

During the last 15 years, hybridization and induced mutation breeding of soybeans have been successful in producing an altered fatty acid composition in the extracted oil. The objective of those investigations was to produce a low-linolenic acid soybena oil. Crude oils extracted from the seeds of three such genotypes were processed in laboratory simulations of commercial procedures to finished deodorized oils. Analysis of the fatty acid composition of the three oils showed the linolenic acid content to be 3.3%, 4.2% and 4.8%. The stability of these finished oils was compared to that of oil from a soybean variety having a linolenic acid content of 7.7% and of a commercial hydrogenated-winterized soybean oil (3.0% linolenic acid). Test and control oils were evaluated by a trained sensory panel initially, after accelerated storage at 60 C and during use at 190 C in room tests. Peroxide values were determined at the time of sensory evaluation. Results indicated there was no significant difference in flavor stability during storage between test and control oils. There was no significant difference, between the oils, in peroxide development during accelerated storage. Compared to control oils, the test oils had improved overall room odor intensity scores and lacked the fishy odors of non-hydrogenated soybean oil and the hydrogenated odors of commercial cooking oil. Presented at the AOCS meeting in Honolulu, HI in May 1986.     

Effect of planting date on sunflower seed oil content,fatty acid composition and yield in Florida

Plantings of sunflower,Heliantbus annuus L., were made 5 times between Feb. 2 and Nov. 15 in Florida so that the effect of planting date on the fatty acid composition of sunflower oil might be assessed. Eleven popular hybrids were planted at Gainesville, FL, on Feb. 2 and 28, April 2, and Aug. 14, and 15 hybrids were planted at Lake Worth, FL, on Nov. 15. Sunflower planted on Nov. 15 would be subjected to freezing temperatures if grown in Gainesville. Yields of sunflower achenes for the four planting dates at Gainesville declined with lateness of planting date. Oleic acid content of the oil (17.6–58.4%) was intermediate for the February plantings, highest for the April planting, and lowest for the late plantings. The linoleic acid content (32.5–71.0%) varied inversely with the oleic acid content. Because sunflower oil is needed for different purposes, such as for salad oil, for deep frying and for making margarines, oil low in linoleic acid (high in oleic acid) as well as oil high in linoleic acid (low in oleic acid) are needed. In Florida, adjusting the planting dates should result in the production of oil of the desired fatty acid composition.     

Effect of culture temperature on fatty acid composition ofChlorella sorokiniana

Chlorella sorokiniana was grown for extraction of fatty acids at seven temperatures ranging from 14 C to 38 C. The predominant fatty acids inC. sorokiniana grown at 38 C were saturated (46% of total); at 22 C, triunsaturated (40% of total); and at 14 C diunsaturated (47% of total). Increasing temperature resulted in an increase in the degree of unsaturation from 14 C to 22 C, but further increases in temperature always resulted in a decrease in unsaturation. At any point in the temperature range used, an increased temperature always resulted in fatty acids with a lower average chain length. Total fatty acid production was greatest at the extremes of temperature and lowest at 26 C. The chain length and degree of saturation of fatty acids increased at temperatures lower than 22 C. Therefore, the fatty acids ofC. sorokiniana do not have an increasingly lower melting point when the culture temperature is reduced at temperatures 22 C or below. Scientific Article No. A1562 Contribution No. 4271 of the Maryland Agricultural Experiment Station.     

Variations in oil content and fatty acid composition with sunflower head size and shape

Medium (8″ dia.) and small (4″) sized sunflower (EC 68415) heads of convex shape yielded seeds with more oil (>44%), unsaturation (I.V.M20) and linoleic acid (>48%) compared to big (12″) sized Both convex and flat shaped flower heads of medium size yielded seeds with more oil (>45%), unsaturation (I.V.>120) and linoleic acid (>48%) than did the concave shaped flower heads of medium size (39.9%, I.V. 112.6, 39.3%, respectively). The oil content, degree of unsaturation and linoleic acid content were thus found to vary with the size and shape of the sunflower head.     

Soybean seed protein and oil contents and fatty acid composition adjustments by drought and temperature

Environmental stress during soybean [Glycine max (L.) Merr.] seed fill can alter the chemical composition of the seed and reduce yield, viability, and vigor. The effect of drought and high air temperature (AT) on soybean seed protein and oil contents have not been reported. The objective of this study was to characterize the protein and oil contents and fatty acid composition of soybean seeds after exposure to drought and high AT during seed fill. Experiments were conducted during two years, in which three drought-stress levels were maintained throughout seed fill. In Experiment I, “Gnome” soybeans were grown at daytime AT of 20 and 26°C, and in Experiment II “Hodgson 78” were grown at 27, 29, 33, and 35°C. Across experiments, severe drought increased protein content by 4.4 percentage points, while oil content decreased by 2.9 percentage points. As drought stress increased, measured by accumulating stress degree days, protein content increased linearly and oil content decreased linearly at each AT. Seeds from plants exposed to 35°C during seed fill contained 4.0 percentage points more protein and 2.6 percentage points less oil than those exposed to 29°C when averaged across drought stress levels. Drought had little effect on the fatty acid composition of the oil, but high AT reduced the proportion of the polyunsaturated components.     

Phospholipid content and fatty acid composition of human heart

Phospholipid content and fatty acid composition of human heart were determined on 36 biopsy specimens collected during open heart surgery. The main phospholipid classes, phosphatidylcholine (PC), phosphatidylethanolamine (PE), diphosphatidylglycerol (DPG), and sphingomyelin (SPH) were separated by HPLC, quantified, and converted to fatty acid methyl esters which were chromatographed on capillary GLC columns. Sex and age (mainly 40–70) of patients had no significant influence on the relative distribution of phospholipid classes and only a slight effect on fatty acid composition. Incorporation oftrans 18∶1 in phospholipid classes was low.cis andtrans octadecenoic isomers seemed to be selectively incorporated, the Δ9 and Δ11cis ortrans isomers being predominant. Human and rat data were compared, and some species differences were noticed. In human PC, palmitic acid is higher and stearic acid much lower than in rat PC. Saturated dimethyl acetals (16∶0 and 18∶0) in PC and PE were greater for humans. Incorporation of 20∶4 n−6 in human PE is higher than in rat PE.     

Improving the fatty acid composition of soybean oil

Efforts to improve the composition of soybean oil by breeding the beans for low linolenic acid in the oil have continued since 1968. This paper reports recent work using hybrid crosses and induced mutations. No lines are yet available that contain oil having less than 3% linolenic acid. Journal Paper No. J-11466 of the Iowa Agriculture and Home Economics Experiment Station, Ames, Iowa, Project No. 2475.     

Determination of oil content of seeds by NIR: Influence of fatty acid composition on wavelength selection

The oil content of nine different types of oilseeds has been determined by near-infrared reflectance (NIR) spectroscopy. A Northstar computer was used to select the wavelengths that best represent the oil content in these seeds. Selected wavelengths were often in the same area of the spectrum, but calibrations differed with respect to the number of wavelength points required and their order of selection. Wavelength assignments for typical functional groups in fatty acids are discussed. The fatty acid composition and the predominant fatty acid component appeared to influence the wavelengths used for the estimation of oil content in each seed type. The mathematical treatments used appeared to affect absorption maxima of all seed types. Spectra of seed oils and their fatty acids indicated variation and closeness of absorption maxima. Paper No. 649 of the Canadian Grain Commission, Grain Research Laboratory, 1404-303 Main Street, Winnipeg, Manitoba, R3C 3G8, Canada. Presented at the 79th annual meeting of the American Oil Chemists’ Society on May 10, 1988, Phoenix, Arizona, U.S.A.     

Oil content and fatty acid composition of seed oil from guayule plants with different chromosome numbers

Guayule, a perennial desert plant, is being developed for domestic production of natural rubber, a strategic commodity for which the United States presently depends totally on foreign sources. At present, rubber alone is not sufficient to make guayule a commercial crop, and additional revenues are being sought from by-products. Because guayule flowers profusely during several years of growth before it is harvested for rubber, seed may also contribute to the economics of guayule production. Seed from 120 plants, including 20 genotypes with 36, 37, 54 and 72 chromosomes, were analyzed for oil content and fatty acid composition. Oil content ranged from 17.1 to 30.5%. On average, seed from diploid and aneuploid plants (with 36 and 37 chromosomes) contained 40.4% more oil than the seed from polyploid plants. The oil consisted of four fatty acids—palmitic (8.7–11.5%), stearic (3.7–6.2%), oleic (6.5–13.9%) and linoleic (69.1–80.2%)—at all ploidy levels. Guayule seed oil was similar to the seed oil from high-linoleic safflower varieties. The use of genetic variation to increase seed yield and seed oil will depend on the absence of negative correlation between oil and rubber production.     

Conifer seeds: Oil content and fatty acid composition

The seed oils from twenty-five Conifer species (from four families—Pinaceae, Cupressaceae, Taxodiaceae, and Taxaceae) have been analyzed, and their fatty acid compositions were established by capillary gas-liquid chromatography on two columns with different polarities. The oil content of the seeds varied from less than 1% up to 50%. Conifer seed oils were characterized by the presence of several Δ5-unsaturated polymethylene-interrupted polyunsaturated fatty acids (Δ5-acids) with either 18 (cis-5,cis-9, 18∶2,cis-5,cis-9,cis-12 18∶3, andcis-5,cis-9,cis-12,cis-15 18∶4 acids) or 20 carbon atoms (cis-5,cis-11 20∶2,cis-5,cis-11,cis-14, 20∶3, andcis-5,cis-11,cis-14,cis-17 20∶4 acids). Pinaceae seed oils contained 17–31% of Δ5-acids, mainly with 18 carbon atoms. The 20-carbon acids present were structurally derived from 20∶1n-9 and 20∶2n-6 acids. Pinaceae seed oils were practically devoid of 18∶3n-3 acid and did not contain either Δ5-18∶4 or Δ5-20∶4 acids. Several Pinaceae seeds had a Δ5-acid content higher than 50 mg/g of seed. The only Taxaceae seed oil studied (Taxus baccata) had a fatty acid composition related to those of Pinaceae seed oils. Cupressaceae seed oils differed from Pinaceae seed oils by the absence of Δ5-acids with 18 carbon atoms and high concentrations in 18∶3n-3 acid and in Δ5-acids with 20 carbon atoms (Δ5-20∶3 and Δ5-20∶4 acids). Δ5-18∶4 Acid was present in minute amounts. The highest level of Δ5-20∶4 acid was found inJuniperus communis seed oil, but the best source of Δ5-acids among Cupressaceae wasThuja occidentalis. Taxodiaceae seed oils had more heterogeneous fatty acid compositions, but the distribution of Δ5-acids resembled that found in Cupressaceae seed oils. Except forSciadopytis verticillata, other Taxodiaceae species are not interesting sources of Δ5-acids. The distribution profile of Δ5-acids among different Conifer families appeared to be linked to the occurrence of 18∶3n-3 acid in the seed oils.     

Fatty acid composition of oil from exotic corn breeding materials

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.     

Developmental changes in fatty acid composition of oil in kernel fractions of corn (Zea mays L.)

Gas liquid chromatography was used to determine the change in fatty acid composition of oil from three kernel fractions (pericarp, endosperm and germ) during kernel maturation of four inbred lines of corn. Inbred lines were sibpollinated, and sampling of ears began six days after pollination (DAP) and continued at three day intervals until 33 DAP and then at weekly intervals until 54 DAP. Proportion of palmitic acid in the pericarp oil rapidly decreased between 6 and 12 DAP while oleic and linoleic acids increased during the same period. Changes in fatty acid composition of oil from the endosperm during kernel maturation were erratic and no consistent trends were evident. In the germ oil, palmitic and linolenic acid proportions decreased during kernel maturation, while oleic acid decreased and linoleic acid increased during kernel maturation for three of the four inbred lines. By about 24 to 27 DAP, the fatty acid composition of oil in the mature kernel was established. Since kernel fractions are of different genetic origin, a study of developmental changes in lipid classes or in fatty acid composition of oil should be limited within kernel fractions that have a similar genetic constitution. Approved as Journal Series Paper No. 723, University of Georgia, College of Agriculture Experiment Stations.     

Effect of fish oil on the fatty acid composition of human milk and maternal and infant erythrocytes

To examine the effect of fish oil supplementation on the fatty acid (FA) composition of human milk and maternal and infant erythrocytes, five lactating women were supplemented with 6 g of fish oil daily for 21d. Usual maternal diets contained 1,147 mg of total n−3 FA, with 120 mg from very long-chain (>C₁₈) n−3 FA. Supplementation increased dietary levels to 3,092 mg of total n−3 FA and 2,006 mg of very long-chain n−3 FA. Milk samples were collected daily, prior to fish oil ingestion, and at 4-h intervals on days 1, 7, 14 and 21. Milk n−3 FA content increased within 8 h and reached steady state levels within one week. The n−6 fatty acid content decreased. Erythrocyte eicosapentaenoic acid content increased from 0.24% to 1.4% (P<0.01) in mothers and from 0.11% to 0.70% (P<0.05) in infants. Docosapentaenoic acid increased from 1.4% to 2.2% (P<0.05) in mothers and from 0.30% to 0.78% (P<0.01) in infants. There was no significant change in docosahexaenoic acid or n−6 fatty acid content. Maternal platelet aggregation responses were variable. No differences in milk or plasma tocopherol levels were noted. Based on a paper presented at the Symposium on Milk Lipids held at the AOCS Annual Meeting, Baltimore, MD, April 1990.     

Cyclopropenoid fatty acid content and fatty acid composition of crude oils from twenty-five varieties of cottonseed

The cyclopropenoid acid content of oils extracted from 22 commercial varieties and 3 botanical species of cottonseed have been determined. The malvalic acid content determined by HBr titration varied from a low of 0.56% to a high of 1.17%. Iodine values of the oils ranged from 96.8 to 111.6 No definite correlation could be established between iodine value and malvalic acid content. Equations for regression lines for the major acids have been calculated from plots of fatty acid composition vs. iodine value. The high degree or correlation suggests that for commercial oils the fatty acid composition can be estimated from the iodine value. Oils of the 3 experimental types of different species showed wide variations in fatty acid composition and represented many of the maximum and minimum values reported. So. Utiliz. Res. Dev. Div., ARS, USDA. ARS, USDA.     

Variability for oil and fatty acid composition in castorbean varieties

Thirty-six castorbean varieties were surveyed for oil and fatty acid composition, in order to determine variability of these seed compounds. A large variability of seed oil percentage was observed, ranging from 39.6 to 59.5%. Concerning the fatty acids, little variability was observed for ricinoleic acid, which was the most abundant in the oil, ranging from 83.65 to 90.00%. The other fatty acids appeared in small concentrations and showed a small range: 0.87 to 2.35, 0.68 to 1.84, 2.96 to 5.64, 3.19 to 5.98, and 0.34 to 0.91%, for palmitic, stearic, oleic, linoleic, and linolenic acid, respectively. Non-significant correlations were observed between fatty acids and seed oil percentage. However, significant correlations were observed among fatty acid concentrations: positive and negative ones. These significant correlations could be associated with the biosynthetic pathways of the fatty acids, which are not fully elucidated. They suggest, however, that selection for a particular fatty acid will tend to increase those positively correlated, and decrease those negative ones. Selection and plant breeding techniques could then be applied to modify the oil content of the castorbean seeds, considering the variability observed. For the fatty acid composition, however, the variability was not large enough to make substantial changes in their concentrations by selection procedures. More varieties should be surveyed to find out if such variability is available.     

Cyclopropenoid fatty acid content and fatty acid composition of crude cottonseed oils from successive solvent extractions

The fatty acid composition and properties of six fractions of oil successively extracted from cottonseed meats has been investigated. The cyclopropenoid fatty acid concn increased regularly from 0.30–1.06%, a 3.5-fold increase. This suggests that the cyclopropenoid constituents of the oil in the seed are less accessible to the solvent. The linoleic acid concn decreased from 56.3–53.1% accounting for a slight reduction in iodine value (I.V.). The first two fractions had a markedly lower phosphatide content than the remaining fractions. Presented at the AOCS Meeting in Chicago, 1964. A laboratory of the So. Utiliz. Res. & Dev. Div., ARS, USDA.     

Increasing n-3 polyunsaturated fatty acid content of fish oil by temperature control of lipase-catalyzed acidolysis

An attempt was made to further increase the content of n-3 polyunsaturated fatty acid (n-3 PUFA) of fish oil by lipase-catalyzed acidolysis (reaction between fish oil and n-3 PUFA-enriched free fatty acid) without solvent. A bioreactor system was constructed composed of a water-jacketed packed-bed column and a substrate reservoir with a circulation pipeline between the packed-bed column and the reservoir. By keeping the temperature of the reservoir at −10°C (for the first 20 h), followed by −20°C (for the subsequent 40 h) during the batch acidolysis, crystals of free fatty acid appeared, which were removed intermittently by a cotton plug packed in the tip of the outlet pipe in the reservoir. The n-3 PUFA content of the triacylglycerol fraction increased a further 10% by the reduced temperature of the reservoir. Bioreactors for Enzymatic Reaction of Fats and Fatty Acid derivatives, Part XV.