Main Saturated Fatty Acids Research Articles

Differential changes in the fatty acid composition of the main lipid classes of chick plasma induced by dietary coconut oil

For a better understanding of the hyperlipidemic function of saturated fat, we have studied the comparative effects of diet supplementation with 10 and 20% coconut oil on the main lipid classes of chick plasma. Changes in fatty acid composition of free fatty acid and triglyceride fractions were parallel to that of the experimental diet. Thus, the increase in the percentages of 12:0 and 14:0 acids may contribute to the hypercholesterolemic effects of coconut oil feeding. Plasma phospholipids incorporated low levels of 12:0 and 14:0 acids whereas 18:0, the main saturated fatty acid of this fraction, also increased after coconut oil feeding. The percentage of 20:4 n-6 was higher in plasma phospholipids than in the other fractions and was significantly decreased by our dietary manipulations. Likewise, minor increases were found in the percentages of 12:0 and 14:0 acids in plasma cholesterol esters. However, the percentage of 18:2 acid significantly increased after coconut oil feeding. Our results show a relationship between fatty acid composition of diets and those of plasma free fatty acid and triglyceride fractions, whereas phospholipids and cholesterol esters are less sensitive to dietary changes.

Interannual and between species comparison of the lipids, fatty acids and sterols of Antarctic krill from the US AMLR Elephant Island survey area

Antarctic euphausiids, Euphausia superba, E. tricantha, E. frigida and Thysanoessa macrura were collected near Elephant ∣ Island ¦ during 1997 and 1998. Total lipid was highest in E. superba small juveniles (16 mg g −1 wet mass), ranging from 12 to 15 mg in other euphausiids. Polar lipid (56–81% of total lipid) and triacylglycerol (12–38%) were the major lipids with wax esters (6%) only present in E. tricantha. Cholesterol was the major sterol (80–100% of total sterols) with desmosterol second in abundance (1–18%). 1997 T. macrura and E. superba contained a more diverse sterol profile, including 24-nordehydrocholesterol (0.1–1.7%), trans-dehydrocholesterol (1.1–1.5%), brassicasterol (0.5–1.7%), 24-methylenecholesterol (0.1–0.4%) and two stanols (0.1–0.2%). Monounsaturated fatty acids included primarily 18:1( n−9) c (7–21%), 18:1( n−7) c (3–13%) and 16:1( n−7) c (2–7%). The main saturated fatty acids in krill were 16:0 (18–29%), 14:0 (2–15%) and 18:0 (1–13%). Highest eicosapentaenoic acid [EPA, 20:5( n−3)] and docosahexaenoic acid [DHA, 22:6( n−3)] occurred in E. superba (EPA, 15–21%; DHA, 9–14%), and were less abundant in other krill. E. superba is a good source of EPA and DHA for consideration of direct or indirect use as a food item for human consumption. Lower levels of 18:4( n−3) in E. tricantha, E. frigida and T. macrura (0.4–0.7% of total fatty acids) are more consistent with a carnivorous or omnivorous diet as compared with herbivorous E. superba (3.7–9.4%). The polyunsaturated fatty acid (PUFA) 18:5( n−3) and the very-long chain (VLC-PUFA), C 26 and C 28 PUFA, were not present in 1997 samples, but were detected at low levels in most 1998 euphausiids. Interannual differences in these biomarkers suggest greater importance of dinoflagellates or some other phytoplankton group in the Elephant Island area during 1998. The data have enabled between year comparisons of trophodynamic interactions of krill collected in the Elephant Island region, and will be of use to groups using signature lipid methodology.

Protein and oil composition of sesame seeds (Sesamum indicum, L.) grown in the Gizan area of Saudi Arabia

Protein content, amino acid and oil composition of two cultivars of Sesamum indicum L. were studied. The cultivars (dark and white) showed ash content in the range of 6.54–7.71%, nitrogen 3.70–4.03%, protein 23.13–25.18% and oil 47.02–49.07%, respectively. Seventeen amino acids were determined including most of the essential and limiting amino acids. Comparison of the present data was made with those reported by the FAO/WHO minimum reference protein. The dark sesame seeds had significantly higher oil and lower protein contents than the white coloured seeds. Oil content were found to be 47.02% and 49.07% in the white and dark coloured seeds, respectively. Analysis by gas liquid chromatography of the oils revealed various fatty acids. The most common recorded in the order of abundance for black and white were: oleic (45.46 and 47.03%), linoleic (33.79 and 35.01%), palmitic (12.03 and 14.02%), stearic (4.93 and 5.72%) and archidic acid (1.00%). Oleic and linoleic were the principal unsaturated fatty acids, while palmitic and stearic were the main saturated fatty acid present. The percentage of the fatty acids fall within the range given by the FAO/WHO committee on fats and oils.

Studies on samh seeds (Mesembryanthemum forsskalei Hochst) growing in Saudi Arabia: 2: Chemical composition and microflora of samh seeds.

The chemical composition of samh seeds have been investigated. Proximate analysis showed a composition of 22.25% protein, 5.7% moisture, 5.6% fat, 4.0% ash, 9.7% crude fiber, and the remainder being total carbohydrates. Mineral element analysis revealed that potassium, magnesium, sodium and calcium were present as the major elements. Iron, manganese, zinc and copper were found at lower levels. However, lead was not detected in the samh seeds. Gas-liquid chromatographic analysis of the methylester of the fatty acids of the samh seeds oil revealed the presence of fourteen fatty acids. Linoleic and oleic acids were the principle unsaturated fatty acids. While palmitic acid was the main saturated fatty acid. Amino acid analysis of the samh seeds showed the presence of seventeen amino acids including eight essential amino acids. Glutamic acid, arginine, and aspartic acid were the major amino acids. Cystine and proline were present in trace amounts. These results some of which have not been reported elsewhere indicate the high nutritional potential of Saudi samh seeds. The total aerobic bacterial count and total sporeformers of seeds were 19 x 10(7) and 5 x 10(4) cfu/g respectively, thus the enterobacteriaceae, B cereus and yeast and molds were 5 x 10(2), 1 x 10(2) and 7 x 10(2) respectively. The seeds were Staph. free and the samh extract had no antimicrobial effect.

Fatty acid compositions of arthropod and cephalopod photoreceptors: interspecific, seasonal and developmental studies

Fatty acid compositions of the compound eyes of insects (soldier-bug, Hemiptera, and silk moth, Lepidoptera), crustaceans (crayfish and grapsid crab, Decapoda) and inner and outer segments of visual cells of a squid (Cephalopoda, Mollusca) were analyzed by gaschromatography for interspecific comparison. Fatty acid compositions showed great variation among species. In insect compound eyes, 16:0 and 18:0 were the main saturated fatty acids, and 18:1 was the dominant unsaturated fatty acid. Silk moth eyes contained, in addition, considerable amounts of 18:2 and 20:5. In crustacean compound eyes, the main saturated fatty acids were 16:0 and 18:0, and 14:0 (5.0%) was only detected in grapsid crabs; the main unsaturated fatty acids were 20:4, 20:5 and 22:6. Both whole eyes and rhabdom fraction of crayfish showed similar profiles of fatty acid compositions. Both inner and outer segments of squid retinae were characterized by high amounts of unsaturated fatty acids, especially 22:6. Compound eyes of grapsid crabs were used for the experiments on seasonal changes of fatty acid compositions. UFA/SFA ratios (weight in % of unsaturated fatty acids saturated fatty acids) were lowest (1.0) in July and highest (2.5) in March, and unsaturation indexes (average number of double bonds per molecule) were lowest (1.5) in July and highest (2.3) in March. Fatty acids 18:0 and 20:1 showed a significant correlation with the changes of seasonal temperature. Fatty acid analysis of the developing compound eyes of silk moths during the pupal stage revealed that eicosapentanoic acid (20:5) increased remarkably in parallel with the development of photoreceptive membranes, the rhabdoms. This suggests that eicosapentaenoic acid may play an important role in formation and function of rhabdoms.

Characteristics and some potential applications of date palm (Phoenix dactylifera L.) seeds and seed oil

The seeds of four date palm (Phoenix dactylifera L.) cultivars, Dekel Noor, Zahidi, Medjool and Halawy, grown in the Arava Valley of southern Israel were analyzed for their inorganic and some organic constituents. The following average values were obtained for the four cultivars on a dry‐weight basis: protein 5.60%, oil 8.15%, fiber 16.13%, and ash 1.13%. Analysis of the mineral elements in the ash gave the following average values: Ca, 1.55%; Na, 0.97%; Mg, 8.07%; K, 27.60%; Fe, 0.73%; Cu, 0.13% and Mn, 0.08%. The oil exhibited the following characteristics (average for the four cultivars): acid value ∼1.04, iodine value 49.5, saponification value 221.0, and unsaponifiable matter 0.8%. Gas‐liquid chromatography revealed that the major unsaturated fatty acid was oleic acid (42.3%), while the main saturated fatty acid was lauric (21.8%). Myristic, palmitic and linoleic acids were also found, average values being 10.9, 9.6 and 13.7%, respectively. Potential uses for date seed oil are considered for cosmetic, pharmaceutical and related specialty products, and to a lesser degree for food products.

Fatty acid composition of acylglycerol and free fatty acid fractions of fat body, haemolymph and muscle lipids in tenebrio molitor l. (Coleoptera Tenebri-Onidae) larvae

The fatty acid compositions of lipid classes in non-esterified fatty acid and in acylglyceroi fractions of Tenebrio molitor L. (Coleoptera: Tenebrionidae) larvae were identified in fat bcdy, haemolymph and muscle by Gas-T iquid Chromatography. The identified 18 fatty acids had sıraight, mostly odd numbered carbon chains wîth C numbers ranging fi’om 14 tc 22. Some of the n3 and n6 members of polyenoics were also separated. Quantitative and some gualitative differences wçre observed in fatty aCid compositions between the lipid classes of the same tissue and between a given lipid fraction of ali tissues. The main saturated fatty acid was C 16:0 in all the lipid classes. Ali the other salurates, namely C 14:0, C 17:0, C 18:0 and C 20:0, were also e isted in various proportions. In FFA fractions C 18:0 was distinctively hıgher than in acylglycerol fractions. High nnsaturation was observed primarily as a resnlt of high proportions of C 18: 1 an .l C 20:4 n3 in 1,2-JÜGj TG and FFA fractions and in MG and 1,3-DG fractions respectively.

Chemical constituents of some Tricholomataceae

Sterols, fatty acids and free amino acids of four species of Tricholomataceae were investigated. They contained ergosterol in high amount and the related sterols, fucosterol, sitosterol, cholesterol and brassicasterol. Linoleic and palmitic are the main unsaturated and saturated fatty acids respectively. The most abundant free amino acids were alanine, valine and proline.

Analysis of lipids and fatty acids during the germination of Brassica campestris cv. esculenta seeds

Turnip tops seeds have a high lipid content (47.22% dry wt.); there is clear predominance of neutral lipids, mainly triglycerides, which represent 71.8% of the total lipid content. These triglycerides decrease during germination, with a maximum descent taking place between the 5th and 6th days of germination; this coincides with the maximum content in fatty acids in the seeds. However, phospholipids and glycolipids increase gradually during the same period. Gas-chromatography studies of the total and free fatty acids of these seeds reveals a predominance of those with an even number of carbon atoms; the proportion of unsaturated fatty acids is greater than that of the saturated kind. Among the former, of note are the high proportions mainly of erucic acid and oleic acid present in many seeds of the Cruciferae; the main saturated fatty acids found are palmitic, stearic and behenic acid.

Influence of sex and dietary fats on platelet lipid biosynthesis in rat

The platelet biosynthesis of total lipids, lipid fractions and fatty acids was determined by incorporation of [ 14C]acetate in normal and castrated rats of both sexes. Comparison was made between animals fed laboratory chow alone, and animals receiving, in addition, for 4 days by stomach tube a saturated (cream) or polyunsaturated (sunflower seed oil) fat. In male rats, the polyunsaturated fat increased slightly the total platelet lipid biosynthesis. The saturated fat drastically reduced it by 43% in comparison to the polyunsaturated fat-fed animals. Normal female rats did not exhibit a similar difference in the platelet lipid synthesis. However, the inhibitory effect of saturated fat on lipid synthesis could be observed in castrated females, although it was less pronounced (27% reduction) than in castrated or normal males (43%). Administration to castrated males of estradiol for 1 month almost completely inhibited the difference induced by the feeding of the different fats in the lipid platelet synthesis of male rats. This difference in the platelet lipid biosynthesis between male and female rats, normal and castrated, was observed mostly in the phospholipid (especially phosphatidylcholine), monoacylglycerol and triacylglycerol fractions and affected primarily the synthesis of the three main saturated fatty acids, 14:0, 16:0 and 18:0. Thus, it seems that, in rat, the short-term administration of a saturated fat induces drastic changes in the platelet lipid biosynthesis, but only in males. The protection observed in females appears to be essentially dependent upon estrogens.

?Oil hyphae? of endolithic lichens and their fatty acid composition

The structure of medullary oil hyphae of twelve endolithic lichen species, belonging to different taxa and colonizing different habitats, was examined by light and electron microscopy. The chemical composition of lipids isolated from the oil hyphae and from two corresponding mycobionts grown in culture was determined. The oil hyphae of the various species appeared in different forms and contained large amounts of lipid in the form of oil globules. The hyphae of mycobionts isolated from two of the endoliths and grown in culture also contained large amounts of lipids. Triacylglycerol was the predominant lipid component in all the organisms examined. Hexadecanoic acid was the main saturated fatty acid; octadecenoic acid and octadecdienoic acid the predominant unsaturated fatty acids. Tetradecanoic, hexadecenoic, octadecanoic and octadectrienoic acids were also detected. The fatty acid distribution pattern appeared unaffected by the nature of substrate and climatic conditions. There is a certain similarity in the fatty acid composition in related species.

Composition and possible significance of fatty acids in the lipid classes in honey bee semen

Phospholipids constitute the major fraction present in the lipids of honey bee semen. The neutral lipids appear to be composed primarily of triglycerides, sterols, sterol esters, and free fatty acids. The extractable seminal lipids are virtually restricted to the spermatozoa, the plasma containing only traces of detectable lipid. In all lipid classes, C16:0 and C18:0 are the main saturated fatty acids. Among the unsaturates, C18:1 is a major component in all classes and C16:1 is one of the main constituents in all fractions except the phospholipids in which it occurs in trace amounts. In the triglycerides, C18:2 is the major unsaturate. The phospholipids contain no appreciable quantities of short-chain fatty acids and C16:0 (23 per cent) and C18:1 (56 per cent) account for 80 per cent of the total fatty acids. The C18 fatty acids constitute about 50 per cent of the total fatty acids present in the triglycerides. The free fatty acid fraction contains about 27 per cent short-chain fatty acids up to C14:1. The sterol ester fraction is almost totally lacking in short-chain fatty acids but is distinguished from all other lipid classes in containing a large percentage of fatty acids with a chain length greater than C18:3. The spermatozoa of the honey bee are highly motile for several hours in the absence of added oxidizable substrate, and the concentration of phospholipids decreases during aerobic incubation. The implications of these results are discussed.