The Sterol,Fatty Acid,and Hydrocarbon Composition of Globodera solanacearum

Globodera solanacearum females were found to have less than 0.01% of dry wt as sterols. Seven sterols were detected in the nematode, with stanols (campestanol and stigmastanol) making tip more than 50% of the total sterols present. Lipid amounted to 29.4% of the dry weight of the nematode. Triglyceride, free fatty acid, and phospholipid classes were composed predominantly of 20:4, 20:1, and 18:1 fatty acids. Of the total weight of fatty acids found in G. solanacearum females, the greatest portion occurred in the triglyceride fraction, followed by the free fatty acid fraction then the phospholipid fraction. Several unidentified hydrocarbons were detected in the nematode. Paraffinic hydrocarbons detected ranged in carbon length from C15 to C29. Total concentration of hydrocarbon composed 0.20% of the dry wt.     

Fatty Acid and Sterol Composition of Mucor genevensis in Relation to Dimorphism and Anaerobic Growth

Fatty acid and sterol content and composition were determined for the dimorphic mold, Mucor genevensis, grown under a variety of experimental conditions. Fatty acids account for 6 to 9% of the dry weight of aerobically grown mycelium, and 70 to 80% of these are unsaturated. The organism contains γ-linolenic acid which is characteristic for Phycomycetes, and in sporangiospores this compound represents 40% of the total fatty acids. Of the sterols found in mycelium, 80% is ergosterol, and stigmasterol was positively identified as one of the minor components. In anaerobically grown yeastlike cells, sterol content is less than 10% of the level found in aerobically grown cells, and fatty acids amount to less than 2% of the dry weight. These fatty acids are predominantly short chain and less than 10% are unsaturated. Yeastlike cells obtained under aerobic conditions by growth in the presence of phenethyl alcohol have fatty acid and sterol compositions characteristic of aerobically grown mycelium. It is concluded that the dimorphology of the organism is not directly related to lipid composition.     

Sterol and Fatty Acid Metabolism in Fusarium oxysporum

The effects of temperatures ranging from 10°C to 35°C on sterol and fatty acid production and hydroxymethylglutaryl CoA reductase (EC 1.1,1.34, HMGCoA reductase) activity have been examined. Growth, based on dry weight, was maximal at 25°C to 30°C. Sterol production and the reductase activity were highest at 15°C after 28~32 hr incubation when the total fatty acids were minimal. Fatty acid unsaturation generally increased with decrease in temperature.     

Assessment of Fatty Acid and Amino Acid Composition of Macroalgae from the Persian Gulf to Characterize their Suitability for Nutritional Supplements

Biology Bulletin - Macroalgae, commonly known as seaweed, can be found worldwide. Seaweeds offer a novel dietary ingredient because of their excellent biochemical composition and health protective...     

Fatty Acid Composition of Spirochaeta stenostrepta

The fatty acid composition of Spirochaeta stenostrepta consists primarily of saturated, branch-chained fatty acids. Iso-C(15), anteiso-C(15), iso-C(17), and anteiso-C(17) represent 66% of the total fatty acids.     

Fatty Acid Composition of Hydrocarbon-Assimilating Yeast

As a part of extensive program on microbial utilization of hydrocarbons, lipid components of Candida petrophillum SD-14 grown on n-alkanes and glucose as carbon sources were studied. In any carbon source, cellular fatty acids of the yeast contained palmitic, palmitoleic, stearic, oleic and linoleic acids as major components.

When n-tridecane was fed to the yeast, fatty acids with odd- and even-number of carbon atoms were produced in almost identical quantity. Another yeast, Torulopsis petrophillum SD-77, also gave a very similar fatty acid pattern by n-tridecane substrate. These phenomena indicate the existence of C₂ addition and β-oxidation of the fatty acid formed in the yeasts.

In the cases of n-tridecane, n-hexadecane and glucose as substrate, about a half of SD-14’s lipid was phospholipid, which consisted of phosphatidyl ethanolamine and phosphatidyl choline principally. Free alcohol and wax were not detected in any case.     

Fatty Acid Composition and the Oxidation of Low-Density Lipoproteins

The effect of the fatty acid composition of low-density lipoprotein (LDL) on copper-ion-catalyzed oxidation of isolated LDL was examined in 18 normolipidemic men. The decrease in LDL linoleic acid concentration (ΔL) during oxidation was found to be strongly correlated with initial LDL linoleic acid concentration (r = 0.976, n = 18, P < 0.001), whereas the production of thiobarbituric acid reacting substances (TBARS) was not. The concentration of oleic acid in LDL was then increased significantly (mean increase 20%, P < 0.05) in 8 male volunteers by a daily dietary supplement of rapeseed oil/muesli for 4 weeks. The mean delay before copper-ion-catalyzed production of conjugated dienes (the lag phase) was significantly (P < 0.001) greater in LDL isolated after the study period (67 min) than that of before the study period (40 mm). The rate of formation of conjugated dienes, ΔL and TBARS production during oxidation of LDL was not significantly altered by the rapeseed oil/muesli supplement. These results suggest that the linoleic acid content of LDL is a determinant of individual variability in LDL oxidation, and that a rapeseed oil/muesli dietary supplement reduces the susceptibility of LDL to oxidation.     

Analysis of Fatty Acid Content and Composition in Microalgae

A method to determine the content and composition of total fatty acids present in microalgae is described. Fatty acids are a major constituent of microalgal biomass. These fatty acids can be present in different acyl-lipid classes. Especially the fatty acids present in triacylglycerol (TAG) are of commercial interest, because they can be used for production of transportation fuels, bulk chemicals, nutraceuticals (ω-3 fatty acids), and food commodities. To develop commercial applications, reliable analytical methods for quantification of fatty acid content and composition are needed. Microalgae are single cells surrounded by a rigid cell wall. A fatty acid analysis method should provide sufficient cell disruption to liberate all acyl lipids and the extraction procedure used should be able to extract all acyl lipid classes.With the method presented here all fatty acids present in microalgae can be accurately and reproducibly identified and quantified using small amounts of sample (5 mg) independent of their chain length, degree of unsaturation, or the lipid class they are part of.This method does not provide information about the relative abundance of different lipid classes, but can be extended to separate lipid classes from each other.The method is based on a sequence of mechanical cell disruption, solvent based lipid extraction, transesterification of fatty acids to fatty acid methyl esters (FAMEs), and quantification and identification of FAMEs using gas chromatography (GC-FID). A TAG internal standard (tripentadecanoin) is added prior to the analytical procedure to correct for losses during extraction and incomplete transesterification.     

Lipid Fatty Acid Composition and Thermophilicity of Cyanobacteria

An analysis of lipid fatty acid composition in several unicellular and filamentous forms of mesophilic and thermophilic cyanobacteria was performed. At 47°C (the temperature of thermophilic cyanobacteria maintenance in the collection), the unicellular thermophilic Synechococcus strains were devoid of polyenoic acids as distinct from the mesophilic forms of this genus at the temperature of 20°C (the temperature of this cyanobacterial maintenance in the collection). In the thermophilic Synechococcus elongatusIPPAS B-267 strain, a decrease in temperature did not result in the occurrence of C18 polyenoic acids, but the quantitative relationship between the saturated and unsaturated fatty acids (S/U ratio) was decreased twofold. In contrast, the culturing of mesophilic strains at 25–32°C resulted in an increase in the S/U ratio due to an increase in the proportion of the 16:0 acid. In the Synechococcus IPPAS B-434 strain, this treatment resulted in a decrease in the relative content of monoenoic, mainly hexadecenoic, acids. The cyanobacterium Gloeobacter violaceus, which lacks thylakoids, and whose photosystems are formed in a cell membrane, contained polyenoic acids. The filamentous thermophilic cyanobacterium Phormidium laminosum, at the maintenance temperature of 47°C, did contain polyenoic acids, but their proportion was considerably lower than that in the filamentous mesophilic forms, such as Tolypothrix sp. and Spirulina platensis. A relative content of hexadecenoic acids in Ph. laminosum was higher than in the mesophilic forms. A possible role of hexadecenoic acids in the processes of adaptation of cyanobacteria to high temperatures is discussed. A relationship between the characteristics of fatty acid composition fixed by evolution and the changes caused by adaptation to a particular environment is considered.     

Fatty Acid and Polar Lipid Composition in the Classification of Kurthia

Strains of Kurthia zopfii were degraded by acid methanolysis and the non-hydroxylated fatty acid esters so released were examined by gas liquid chromatography. The major fatty acid types were straight-chain, anteiso - and iso -methyl branched-chain acids. Monounsaturated fatty acids were not detected. The major fatty acid in five of the six strains examined consisted of 12-methyltetra-decanoic ( anteiso -C₁₅) acid. The other strain possessed major amounts of both 13-methyltetradecanoic ( iso -C₁₅) and anteiso -C₁₅ acids. Polar lipids of all the strains were examined by two-dimensional thin-layer chromatography. All possessed a very simple polar lipid composition consisting of diphosphatidylglycerol, phosphatidylglycerol and phosphatidylethanolamine.     

皱肋文蛤氨基酸含量及脂肪酸组成分析

测定了皱肋文蛤(Meretrix lyrata)软体部分的氨基酸含量与脂肪酸组成.共检出17种氨基酸,总含量为软体部干重的52.26%;4种呈味氨基酸(天门冬氨酸、谷氨酸、甘氨酸和丙氨酸)的含量为22.07%,占氨基酸总量的42.23%;必需氨基酸(EAA)总含量为20.72%,其必需氨基酸的构成比例基本符合FAO/W...     

Nutritional Alteration of the Fatty Acid Composition of a Thermophilic Bacillus Species

The fatty acid composition of a thermophilic Bacillus sp. was altered by the addition of isobutyrate, isovalerate, alpha-methylbutyrate, leucine, and isoleucine to the growth medium. With isobutyrate, 81% of the fatty acids had 16 carbon atoms and 79% were iso-fatty acids with an even number of carbon atoms. With leucine, 58% of the fatty acids had 15 carbon atoms and 86% were iso-fatty acids with an odd number of carbon atoms. With isoleucine, 72% of the fatty acids had 17 carbon atoms and 88% were anteiso-fatty acids with an odd number of carbon atoms. Thus, by altering the composition of the growth medium, cells were produced in which the majority of the fatty acids had either 15, 16, or 17 carbons and belonged to each of the three groups of branched-chain fatty acids. The wide variation observed in the fatty acid composition makes it unlikely that any specific branched-chain fatty acid is required for vital functions.     

外源脂肪酸对酒精诱导自絮凝颗粒酵母细胞膜磷脂脂肪酸组成变化的影响

实验将自絮凝颗粒酵母培养于同时添加脂肪酸 (0.6mmol/L)和酒精 (6 %～ 9% ,V/V)条件下以考察其细胞膜磷脂脂肪酸组成的变化。与单独添加棕榈酸相比 ,同时添加酒精引起细胞膜磷脂棕榈酸含量明显增加 ,伴随 9十四碳烯酸、棕榈油酸和油酸含量明显减少 ;与单独添加亚油酸相比 ,同时添加酒精未引起细胞膜磷脂亚油酸含量明显变化 ,但引起油酸含量明显增加 ,伴随 9 十四碳烯酸、棕榈油酸和棕榈酸含量减少 ;与单独添加亚麻酸相比 ,同时添加酒精引起细胞膜磷脂亚麻酸含量减少 ,伴随油酸含量显著增加 ,同时 9 十四碳烯酸、棕榈油酸和棕榈酸含量减少。存活率实验证实 ,上述变化是菌体对酒精刺激的适应性响应 ,因为 ,与培养于仅添加脂肪酸条件下的菌体相比 ,培养于同时添加酒精条件下的菌体耐酒精能力明显提高。研究表明 ,棕榈酸和油酸都可通过加强细胞膜渗透屏障而提高菌体的耐酒精能力 ,这是饱和脂肪酸 (SFA)与不饱和脂肪酸 (UFA)可提高同一菌株耐酒精能力的新的实验现象 ,揭示UFA与SFA在影响酵母菌耐酒精能力的机制上存在共同的作用方式     

Cellular Fatty Acid Composition and Identification of Rumen Bacteria

The fatty acid compositions of 21 pure cultures of rumen bacteria, representing 12 genera and 14 species, were compared as methyl esters. Each organism possessed a consistent and reproducible fatty acid profile. Overlapping similarities and differences in composition did not allow differentiation between families or genera. Although species differentiation was possible, fatty acid composition appeared to be only an aid in the identification of bacteria.     

Fatty Acid Composition of Lipid Extracts of a Thermophilic Bacillus Species

Studies on the relationship between cell synthesis and energy utilization in Hydrogenomonas eutropha have shown that the amount of oxidative energy required for synthetic reactions depends on the conditions of growth. The energy of hydrogen oxidation was most efficiently used when growth conditions were optimal (continuous culture, cells in exponential growth phase) and when the rate of growth was limited by H(2) or O(2) supply. Under these conditions, 2 to 2.5 atoms of oxygen were consumed by the oxyhydrogen reaction for the concomitant conversion of 1 mole of CO(2) to cell matter. This conversion efficiency, expressed as the O/C energyyield value, was observed with continuous cultures. A less efficient conversion was found with batch cultures. With limiting concentrations of CO(2) the rate of hydrogen oxidation was relatively high, and the O/C value was dependent on the growth rate. With nonlimiting concentrations of CO(2), the rate of hydrogen oxidation was strictly proportional to the rate of CO(2) fixation, and the O/C value was independent of growth rate. This proportionality between the rate of H(2) oxidation and the rate of CO(2) fixation suggested that energy supply regulates the (maximum) rate of growth. From the energy-yield measurements, we concluded that the oxidation of 1 mole of H(2) yields the equivalent of 2 moles of adenosine triphosphate for H. eutropha, and that at least 5 moles of this high-energy phosphate is required for the conversion of 1 mole of CO(2) into cellular constituents.     

Fatty Acid Composition of Phrenosine in Beef Spinal Cord

Although a number of studies have focused on the higher ethyl pyruvate antioxidative activity than its sodium salt under various stress conditions, and the greater protective properties of the ester form have been suggested as the effect of better cell membrane penetration, the molecular mechanism has remained unclear. The aim of the present study was therefore to compare the antioxidative activities of sodium and ethyl pyruvate under in vitro conditions by using a liver homogenate as the model for cell membrane transport deletion. The potential effect of ethanol was also evaluated, and hypochlorous acid was used as an oxidant. Our data indicate the concentration-dependent scavenging potency of both sodium and ethyl pyruvate, with the ester having higher activity. This effect was not related to the presence of ethanol. Better protection of the liver homogenate by ethyl pyruvate was also apparent, despite the fact that cell membrane transport was omitted.     

Fatty Acid Composition of Three Species of Litsea

The seed oils of three species (Litsea cubeba (Lour.) Pers, L. auriculata Chien et Cheng, L. subcoriacea Yang et P. H. Huang) were examined and the fatty acid composition of these oils was determined by GLC. Their major fatty acid was identified as lauric acid, Its amount ranged from 34.6%–75.4%. The major acid of the fruit coat oil from L. subcoriacea Y. H. Huang was different from that of the seed oil. The former contained 50% linoleic acid. The unsaturated C10, C12, C14 acids of the seed oil from L. cubeba (Lour.) Pers were separated by distillation, column chromatography and were identified by Periodate-Perman-ganate oxidation, IR, NMR and MS. They are cis-4-decenoic, cis-4-dodecenoic and cis-4-tetradecenoic acids respectively.     

The Manipulation of the Fatty Acid Composition of Glycerolipids in Cyanobacteria Using Exogenous Fatty Acids

The fatty acid composition of the major diacylglycerolipidsof Anacystis nidulans R2 cells was modified by the careful additionof exogenous fatty acids to the growth medium of the cyanobacteria.In this way it is possible to incorporate significant levelsof different fatty acids into the membranes of the cells andchange their physical properties without changing other environmentalconditions. The exogenous fatty acid reduces or inhibits thebiosynthesis of native fatty acids and substitutes for themin all the major diacylglycerolipids. Although modifying thefatty acid composition in this way is lethal above certain concentrations,the data demonstrate a remarkable ability of the cells to growand develop over a wide range of fatty acid compositions. Similardata show that the fatty acid composition of Synechocystis sp.6803 cells also undergo significant changes in fatty acid compositionon the addition of exogenous fatty acid to the growth mediumand can tolerate similar changes in the degree of unsaturationof the fatty acids of the diacylglycerolipids of the cell membranes. (Received September 4, 1989; Accepted March 13, 1990)