Chemical Composition Of Lipids Research Articles

Prominent hypertrophy of perivascular adipocytes due to short-term high fat diet

Excessive lipid accumulation is a serious problem in obesity leading to adipose tissue (AT) overgrowth, chronic inflammation, endothelial dysfunction, and elevated risk of cardiovascular complications. In this work, Raman techniques coupled with fluorescence imaging were applied to characterize the effects of short-term (2 weeks) and extended (up to 8 weeks) high-fat diet (HFD) feeding on various depots of the adipose tissue of young and mature mice. Our results proved the synergistic effect of age and HFD-induced obesity manifested by changes in the morphology of adipocytes and the chemical composition of lipids. After 2 weeks of HFD feeding of young animals, substantial hypertrophy of adipocytes but only for the periaortic adipose tissue was detected with a significant decrease in lipid unsaturation degree solely in the epididymal white adipose tissue. The periaortic AT did not altered chemically due to short-term HFD feeding, however, it changed with age and with prolonged exposure to harmful factors. For older animals only brown AT remains resistant on HFD underlying its protective role and highlighting its potential as a target in obesity therapies.

Inactivation of Bacteria by γ-Irradiation to Investigate the Interaction with Antimicrobial Peptides

The activity of antimicrobial peptides (AMPs) has been investigated extensively using model membranes composed of phospholipids or lipopolysaccharides in aqueous environments. However, from a biophysical perspective, there is a large scientific interest regarding the direct interaction of membrane-active peptides with whole bacteria. Working with living bacteria limits the usability of experimental setups and the interpretation of the resulting data because of safety risks and the overlap of active and passive effects induced by AMPs. We killed or inactivated metabolic-active bacteria using γ-irradiation or sodium azide, respectively. Microscopy, flow cytometry, and SYTOX green assays showed that the cell envelope remained intact to a high degree at the minimal bactericidal dose. Furthermore, the tumor-necrosis-factor-α-inducing activity of the lipopolysaccharides and the chemical lipid composition was unchanged. Determining the binding capacity of AMPs to the bacterial cell envelope by calorimetry is difficult because of an overlapping of the binding heat and metabolic activities of the bacteria-induced by the AMPs. The inactivation of all active processes helps to decipher the complex thermodynamic information. From the isothermal titration calorimetry (ITC) results, we propose that the bacterial membrane potential (Δψ) is possibly an underestimated modulator of the AMP activity. The negative surface charge of the outer leaflet of the outer membrane of Gram-negative bacteria is already neutralized by peptide concentrations below the minimal inhibitory concentration. This proves that peptide aggregation on the bacterial membrane surface plays a decisive role in the degree of antimicrobial activity. This will not only enable many biophysical approaches for the investigation between bacteria and membrane-active peptides in the future but will also make it possible to compare biophysical parameters of active and inactive bacteria. This opens up new possibilities to better understand the active and passive interaction processes between AMPs and bacteria.

Abundance of lipids in differently sized aggregates depends on their chemical composition

Evidence for a vital role of soil mineral matrix interactions in lipid preservation is steadily increasing. However, it remains unclear whether solvent-extractable (‘free’) or hydrolyzable (‘bound’) lipids, including molecular proxies, e.g., for cutin and suberin, are similarly affected by different stabilization mechanisms in soil (i.e., aggregation or organo-mineral association). To provide insights into the effect of these stabilization mechanisms on lipid composition and preservation, we investigated free and bound lipids in particulate and mineral soil fractions, deriving from sand- and silt-/clay-sized aggregates from a forest subsoil. While free lipids accumulated in sand-sized aggregates, the more complex bound lipids accumulated in silt- and clay-sized aggregates, particularly in the respective mineral fractions < 6.3 µm (fine silt and clay). The presence of both, cutin and suberin markers indicated input of leaf- and root-derived organic matter to the subsoil. Yet, our cutin marker (9,10,ω-trihydroxyoctadecanoic acid) was not extracted from the mineral aggregate compartments < 6.3 µm, perhaps due to its chemical structure (i.e., cross-linking via several hydroxy groups, and thus higher ‘stability’, in macromolecular structures). Combined, these results suggest that the chemical composition of lipids (and likely also that of other soil organic matter compounds) governs interaction with their environment, such as accumulation in aggregates or association with mineral soil compartments, and thus indirectly influences their persistence in soil.

Chemical Composition of Lipids from Peat-Forming Leafy Mosses of Eutrophic Swamps of Western Siberia and Altai

The molecular composition of lipids in three samples of leafy mosses (Aulacomnium palustre, Warnstorfia fluitans, and Calliergon giganteum) has been determined. The revealed acyclic compounds included normal and isoprenoid alkanes, isoprenoid alkenes, normal and isoprenoid ketones, carboxylic acids and their esters, alcohols, and aldehydes. Among cyclic compounds, bi-, tri- and tetracyclic polycycloaromatic hydrocarbons (PAHs), bicyclic and pentacyclic terpenoids, steroids and tocopherols have been observed. The identified organic compounds consisted mainly of carbocyclic acids and n-alkanes with the prevalence of C27 homologues. A. palustre is characterized by a reduced content of isoprenoid compounds, alcohols, and ketones, while the content of unsaturated acids, pentacyclic terpenoids, and aldehydes is rather heightened. A. palustre differs from W. fluitans and C. giganteum in the steroid composition and contains eremophylene, a sesquiterpenoid, which is absent in the mosses of the family Amblystegiaceae. Compared to C. giganteum, W. fluitans has a higher content of lycopadiene, carboxylic acids, n-alkanes, phyt-2-ene, aldehydes, esters, squalene, diploptene, α-tocopherol, and triphenyl phosphates.

LIPIDS OF INONOTUS RHEADES (HYMENOCHAETACEAE): INFLUENCE OF SUBSTRATE AND LIGHT MODE ON FATTY ACID PROFILE OF MYCELIUM

Controlled regulation of biosynthesis in higher fungi is currently an intensively developing field of the modern biotechnological industry. A promising object of such studies is the mycelial culture of Inonotus rheades (Pers.) P. Karst. Family Hymenochaetaceae has some biological activities that were previously shown by us. For the present study, the composition of fatty acids of I. rheades mycelium was firstly studied and 12 compounds including the dominant linoleic (C18:2 ω6) and palmitic acids (C16:0) were detected. It was found that the application of various substrates for the cultivation of I. rheades mycelium leads to changes in the quantitative composition of fatty acids. The use of Populus tremula wood resulted to an increase in the content of unsaturated fatty acids and decreasing of the concentration of unsaturated fatty acids comparing with mycelium grown on Betula pendula wood. The effect of the light mode on the fatty acid profile of I. rheades mycelium was characterized by a complex of changes in the chemical composition of lipids. Depending on the wavelength of the light used, both qualitative and quantitative changes were observed. The results of this studies showed that the substrate and the light mode affect on the composition of the fatty acids of I. rheades mycelium.

&lt;b&gt;Chemical composition of lipids from native and exotic fish in reservoirs of the state of Ceará, Brazil

Current study analyzes the chemical composition of lipids in fish commonly found in the dams of the state of Ceara, Brazil, namely Pterygoplichthys pardalis (bodo), Hoplias malabaricus (traira), Cichla ocellaris (tucunare), Prochilodus brevis (curimata) and Oreochomis niloticus (tilapia). The animals were collected during the summer and Folch extraction procedure was used for the extraction of lipids, whilst Iupac methodology (International Union of Pure and Applied Chemistry [Iupac], 1987) was used to methylate the fatty acids. Methyl esters were analyzed by GC/MS and the different components in fish oil were identified. Palmitic acid, C16:0 (35.71-45.02%), was the saturated fatty acid with the highest percentage, while oleic acid, C18:1Δ9 (10.62-25.29%) had the highest percentage among the unsaturated fatty acids. The chemical composition of analyzed freshwater fish lipids revealed low levels of polyunsaturated fatty acids.

Investigation of the lipophilic constituents of Camphorosma lessingii

The genus Camphorosma (Chenopodiaceae) is represented by four species (C. lessingii, C. monspeliacum, C. annuum, and C. soongoricum) in salt marshes and rocky slopes of central and south Asia. Three species are indigenous to the flora of Kazakhstan (C. lessingii, C. monspeliacum, and C. soongoricum) [1–3]. The genus Camphorosma is used in folk medicine to treat various diseases such as lung diseases and rheumatism, and used in Central Asia externally to treat fungal skin diseases, and internally as a diuretic, diaphoretic, stimulant, and aphrodisiac [1, 2]. From this view point, it is definitely interesting as a raw material source for drug production.We studied previously the chemical composition of Campharosma monspeliacum L. [4, 5], and now we continue investigation of another species of the genus Campharosma not studied before. Because lipids affect the bioavailability and general pharmacotherapeutic effect of plant extracts and preparations based on them, and some of the biologically active compounds of plants are lipids that play an integral role in the metabolism of living organisms, our goal was to study the lipids of Camphorosma lessingii. We studied the chemical composition of lipids from the flowering parts of Camphorosma lessingii collected from the Almaty region in Kazakhstan. GC-MS analysis of the hexane extract of C. lessingii was performed by electron impact ionization (EI) (gas chromatography coupled with mass spectrometry) using a silica capillary column coated with PES [He carrier gas flow rate 1 mL/min, gradient column temperature 60–290 C, injector temperature 310oC, and ion source detector (EI-70 eV)]. The components were identified from the peak areas without using correction factors and by comparing their retention times and full mass spectra with the NIST and Wiley electronic libraries. GC-MS analysis revealed the presence of 12 known compounds comprising 32.31% of the total lipophilic constituents (Table 1). In addition to a number of unknown constituents, which represent about 67.69%, this high percent prompted us to do further comprehensive research on these lipophilic constituents.

Chemical composition of lipids in brewer's spent grain: A promising source of valuable phytochemicals

Brewer's spent grain (BSG) is an important by-product from the brewing process produced in high amounts worldwide. BSG is rich in carbohydrates, lignin, proteins and lipids. In this work, the chemical composition of the lipids in BSG was studied in detail by gas chromatography and mass spectrometry. The predominant lipids were triglycerides (67% of total extract), followed by a series of free fatty acids (18%). Lower amounts of monoglycerides (1.6%) and diglycerides (7.7%) were also identified among the lipids in BSG, together with minor amounts of other aliphatic series such as n-alkanes and alkylresorcinols. Steroid compounds (steroid hydrocarbons, steroid ketones, free sterols, sterol esters and sterol glycosides) were also found in important amounts in BSG (ca. 5%), with free and conjugated sterols being the most abundant steroids. BSG can thus be regarded as a valuable source of phytochemicals of interest for the pharmaceutical, cosmetic, food or other industries.

Chemical Composition of Lipids Present in Cat and Dog Oocyte by Matrix‐Assisted Desorption Ionization Mass Spectrometry (MALDI‐ MS)

The aim of the present study was to investigate the level of information on the chemical structures and relative abundances of lipids present in cat and dog oocytes by matrix-assisted laser desorption mass spectrometry (MALDI-MS). The MALDI-MS approach requires a simple analysis workflow (no lipid extraction) and few samples (two or three oocytes per analysis in this work) providing concomitant profiles of both intact phospholipids such as sphingomyelins (SM) and phosphatidylcholines (PC) as well as triacylglycerols (TAG). The lipids were detected in oocytes by MALDI using dihydroxybenzoic acid (DHB) as the matrix. The most abundant lipid present in the MS profiles of bitch and queen oocytes was a PC containing 34 carbons and one unsaturation [PC (34:1)]. Oocytes of these two species are characterized by differences in PC and TAG profiles detected qualitatively as well as by means of principal component analysis (PCA). Cat oocytes were mainly discriminated by more intense C52 and C54 TAG species and a higher number of unsaturations, indicating predominantly linoleic and oleic fatty acyl residues. Comparison of the lipid profile of bitch and queen oocytes with that of bovine oocytes revealed some similarities and also some species specificity: TAG species present in bovine oocytes were also present in bitches and queens; however, a more pronounced contribution of palmitic, stearic and oleic fatty acid residues was noticed in the lipid profile of bovine oocytes. MALDI-MS provides novel information on chemical lipid composition in canine and feline oocytes, offering a suitable tool to concomitantly monitor, in a nearly direct and simple fashion the composition of phospholipids and TAG. This detailed information is highly needed to the development of improved protocols for in vitro culture and cryopreservation of cat and dog oocytes.

Chemical composition of Desulfovibrio desulfuricans lipid A

Lipopolysaccharides also called endotoxins are an integral component of the outer membrane of Gram-negative bacteria. When released from the bacterial surface, they interact with a host immune system, triggering excessive inflammatory response. Lipid A is the biologically most active part of endotoxin, and its activity is modulated by the quantity, quality and arrangement of its fatty acids. Desulfovibrio desulfuricans is sulfate-reducing, Gram-negative bacterium that is supposed to be opportunistic pathogens of humans and animals. In the present study, chemical composition of lipid A from various strains of D. desulfuricans was analyzed by gas chromatography/mass spectrometry. It was found that the fatty acid component of the lipid A contains dodecanoic, tetradecanoic, 3-hydroxytetradecanoic and hexadecanoic acids, and its carbohydrate core is composed of glucosamine. The analysis of 3-acyloxyacyl residue of the lipid A revealed the presence of amide-bound 3-(dodecanoyloxy)tetradecanoic and 3-(hexadecanoyloxy)tetradecanoic acids and ester-bound 3-(tetradecanoyloxy)tetradecanoic acid. It was concluded that both fatty acid and 3-acyloxyacyl residue profiles of the lipid A from the studied bacteria were similar to those of E. coli and S.enterica.

Chemical composition of lipids in populations and species of Enchytraeus (Annelida, Oligochaeta) and Tisbe (Arthropoda, Crustacea)1

The composition of lipids from several Enchytraeus (Annelida, Oligochaeta) and Tisbe (Arthropoda, Crustacea) populations or species, respectively, has been investigated using chromatographic and spectrometric methods. Triglycerides and polar components were found to be the predominant components. In both genera, the fatty acid moiety of the triglycerides consisted mainly of saturated and unsaturated C14-, C16- and C18-compounds; particularly, in Tisbe populations additionally branched constituents were present. Predominantly fatty acids in Tisbe populations were C16-compounds whereas C14-compounds were major constituents in Enchytraeus indicating a differently oriented synthetase activity in these groups. The analysis of the fatty acid profiles and the phospholipid patterns revealed distinct groups within the Enchytraeus populations which can be discriminated by a different balance of s-oxidation and desaturase systems. These findings are discussed in context with the fatty acid metabolism in these organisms considering the results obtained with other methods and evaluating the applicability of lipid analysis in these organisms for chemosystematic investigations.

Wax and suberin development of native and wound periderm of potato (Solanum tuberosum L.) and its relation to peridermal transpiration.

Native and wound periderm was isolated enzymatically from potato (Solanum tuberosum L. cv. Desirée) tubers at different time intervals between 0 days up to 4 weeks after harvesting. Wound periderm formation was induced by carefully removing native periderm from freshly harvested tubers before storage. The chemical composition of lipids (waxes) obtained by chloroform extraction, as well as the monomeric composition of native and wound suberin polymer after transesterification by boron trifluoride/methanol, was analyzed using gas chromatography and mass spectrometry. Both types of periderm contained up to 20% extractable lipids. Besides linear long-chain aliphatic wax compounds, alkyl ferulates were detected as significant constituents. In wound periderm they amounted to more than 60% of the total extracts. Within 1 month of storage, suberin amounts in the polymer increased 2-fold in native periderm (180 microg cm(-2)), whereas in wound periderm about 75.0 microg cm(-2) suberin polymer was newly synthesized. Native potato tuber periderm developed a very efficient transport barrier for water with permeances decreasing from 6.4 x 10(-10) m s(-1) to 5.5 x 10(-11) m s(-1) within 1 month of storage. However, the water permeability of wound periderm was on average 100 times higher with permeances decreasing from 4.7 x 10(-8) m s(-1) after 3 days to only 5.4 x 10(-9) m s(-1) after 1 month of storage, although suberin and wax amounts in wound periderm amounted to about 60% of native periderm. From this result it must be concluded that the occurrence of suberin with wax depositions in cell walls does not necessarily allow us to conclude that these cell walls must be nearly perfect barriers to water transport. In addition to the occurrence of the lipophilic biopolymer suberin and associated waxes, the still unknown molecular arrangement and precisely localized deposition of suberin within the cell wall must contribute to the efficiency of suberin as a barrier to water transport.

Lipids from flax fibers and their fate in alkaline pulping.

The chemical composition of lipids from bast fibers of flax (Linum usitatissimum), which are commonly used for high-quality paper pulp production, was thoroughly studied by gas chromatography-mass spectrometry. The main compounds identified were waxes, series of long chain n-fatty alcohols, n-aldehydes, n-fatty acids, and n-alkanes. Free and esterified sterols and triterpenols, steroid hydrocarbons, steroid and triterpenoid ketones, as well as sterol glycosides were also found in the flax bast fibers. On the other hand, the fate of these lipophilic compounds in alkaline pulping of flax fibers was investigated by analyzing two pulps obtained under distinct industrial cooking conditions. The results revealed that while waxes could be efficiently hydrolyzed during pulping depending on the alkali charge, most of the other lipophilic compounds present in flax fibers survived cooking and were present in the unbleached pulps.

Public health and the safety of milk and milk products from sheep and goats

Goats and sheep rank third and fourth in terms of global milk production from different species, but unlike cow milk, which has stringent hygiene and quality regulations, microbiological standards for the production and distribution of goat milk and sheep milk are more relaxed. Difficulties in managing the sanitary quality of sheep and goat milk derive from a series of factors including the low level of production per head, the milking system, the difficulty involved in machine milking, the conditions under which the herds or flocks are raised, adverse climatic conditions and the spread of production over a wide geographic area. Fresh goat milk is consumed by infants and others with allergies to cow milk and is also used for on-farm manufactured cheese, with or without thermal treatment. The high fat content and peculiar taste of cheeses made from ewe milk are also very popular. These cheese varieties, which are mostly still of 'artisan-type', are not covered by regulatory definitions and the dispute over the use of raw versus pasteurised milk is still alive. However, in documented intoxications recorded after the consumption of cheese, there has always been evidence of incorrect temperature control during pasteurisation, the deliberate addition of raw milk, or contamination during storage. Compositional differences between the milk from cows, ewes and goats (chemical composition of lipids, phosphatase level, freezing point, natural bacterial inhibitor levels, somatic cell count, etc.) preclude the nondiscriminatory use of bovine standards for regulatory purposes. Quality standards adjusted for the specifics of ewe/goat milk should be considered. The production of safe cheese is linked to a series of conditions which ensure consumer health, primarily pasteurisation. In the absence of pasteurisation, all cheeses made from raw milk should be subjected to strict periodic controls.

A study of changes in the fat content of some varieties of dry sausage during the curing process

The influence of the curing of dry sausage (chorizo, saucisson, salami) on the chemical composition of lipids was studied in terms of what affects the oxidation and resulting production of volatile aldehydes, mainly hexanal. Microbial fermentation initially increases the unsaturation, although this phenomenon is reversed during the drying-curing process. In this phase the saturation/unsaturation ratio rises in C16 and C18 fatty acids, the increase being higher in chorizo and lower in salami. Stearic acid appears to increase more than palmitic acid, and C16 quotient values show significant differences across a range of commercially-sold brands of each type of sausage. Unsaturation varies in parallel with the iodine value in the three cases studied. Lipolytic phenomena produce fatty acids with a greater amount of linoleic acid than oleic acid. The oxidation of these fatty acids is progressive regardless of whether TBA or carbonyl values are measured. Nevertheless, significant correlations of hexanal concentrations are not evident. The formation of butanal and pentanal (<2 μmol) is very low, and hexanal concentration fluctuates (11–111 μmol) among commercial brands and types of sausage. These concentrations are always much higher in chorizo samples than in those of salami. Statistical multivariant analysis highlights the greater significant differences in salami samples, a sausage which reflects the lack of homogeneity between different industrial processes.

Chemical Composition of Lipids, Especially Triacylglycerol, in Grape Seeds

Chemical Composition of Lipids, Especially Triacylglycerol, in Grape Seeds

Chemical composition of lipids, especially triacylglycerol, in grape seeds.

Total lipids were extracted from five varieties of grape seeds and systematically analyzed for their chemical compositions. The yields of the total lipids were 10–16%, and triacylglycerol (TG) usually amounted to c. 90% of the whole. From a reversed-phase high-performance liquid Chromatographic analysis, the major molecular species of TG were shown to be trilinolein (40%), oleoyldilinolein (21%) and palmitoyldilinolein (18%). The component fatty acids were asymmetrically distributed at C-1 and C-3 of the TG molecule. Palmitic acid was exclusively located at the C-1 position, although unsaturated fatty acids, especially linoleic acid, were predominant at the C-1 position, as at the C-2 and C-3 positions. Compared with TG, higher proportions of palmitic and linolenic acids were generally observed in thirteen other lipid classes isolated from grape seeds, although the fatty acid compositions of the diacylglycerol and free fatty acids were roughly identical with that of TG. As component sterols, sitosterol, c...

Effect of phosphate and acidosis on sensitivity of cardiac myofibrils to calcium

Electric stability of the membranes of the mitochondria and liposomes formed from mitochondrial lipids was studied. The mitochondria were isolated from the liver of euthyroid or hyperthyroid rats kept on the diets with varying degree of food fat unsaturation. In the first group animals, butter was used as a fatty component of the diet whereas the second group animals received sunflower oil. The electric stability of the membranes of the mitochondria and respective liposomes appeared lower in the first group animals as compared with those in the second group animals. Hyperthyrosis was accompanied by the increased electrical stability of mitochondrial lipids in both the groups. At the same time the liposomal membranes were similar as regards the electric stability, whereas the electric stability of the mitochondrial membranes in the first group hyperthyroid and euthyroid rats was lower than in the organelles of the second group animals. It is thus assumed that the electric stability of the mitochondria is determined not only by the chemical composition of lipids but also by other factors.

Water-Soluble Lipoproteins from Yolk Granules in Sea Urchin Eggs

The chemical composition of yolk lipoproteins (YLP-1, 2, and 3) was determined. YLP-1, 2, and 3 were quite similar as regards the chemical composition of lipids, proteins, and carbohydrate moieties. Each lipoprotein has an average dry weight composition of lipids (55--72%) and apo-lipoproteins (28--45%) containing protein, hexose, hexosamine, and sialic acid. In each lipoprotein, triacylglycerol is a major lipid component (70--83%), followed by phospholipid (8--16%), cholesterol (free and esterified, 8--10%), and free fatty acid (3--4%). Phosphatidylcholine and phosphatidylserine account for 68--74% and 16--24% of the phospholipids, respectively. The fatty acid compositions of total lipids from each lipoprotein are quite similar, with a high degree of unsaturation (63--65%). The carbohydrate content of apolipoprotiens from each lipoprotein is remarkably high (27--31% of apo-lipoproteins) and their composition is very simple: mannose and glucosamine are major constituents in the polysaccharide moiety of each lipoprotein and sialic acid is all in the N-glycolyl form. The amino acid compositions of apo-lipoproteins are quite similar in YLP-1, 2, and 3, with high contents of aspartic acid, glutamic acid, threonine, serine, and leucine. Furthermore, a small amount of glycolipids is present in the yolk lipoproteins. They were separated into six components on TLC. All of them are resorcinol-positive, indicating the presence of sialoglycolipids.

?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.