Lipid composition of the liver oil of the ray, Himantura bleekeri

If rays are traditionally fished for their caudal fins, the rest of the body is wasted, except part of the skin that can be transformed into leather. Liver oil of the ray, Himantura bleekeri, was characterized in terms of lipid class composition and fatty acid profile. Liver oil content was high and represented 54% of the liver weight (w/w). Neutral lipids were predominant (92%), major components being triacylglycerols (63%). Other neutral lipids identified were hydrocarbons, sterol esters, mono- and di-acylglycerols, free fatty acids, sterols and glyceryl ethers. Polyunsaturated fatty acids of the n−3 series, namely eicosapentaenoic and docosahexaenoic acids, were high (4% and 16%, respectively). Cholesterol was the major component in the sterol fractions (free or esterified). Hydrocarbons were up to 30 carbons and squalene was present at the level of 22%. Thus, this liver oil proved to be an adequate source of n−3 fatty acids and other valuable lipidic compounds.     

Fatty acid composition and oxidation of cowpea (Vigna unguiculata) flour lipid

The lipids extracted from cowpea flour before and after storage at water activities (a_w) of 0·11, 0·33 and 0·75 and at 5, 25 and 40°C for 6 months were examined for their fatty acid composition and oxidation.Linoleic, linolenic and oleic acids, in decreasing order, were the unsaturated fatty acids recorded. The saturated fatty acids were palmitic, stearic and arachidic in decreasing order. The total unsaturated fatty acids concentration was higher than the total saturated fatty acids, with palmitic acid being the single dominant fatty acid.$\text{Saturated}\text{unsaturated}$ fatty acid ratios ($\text{s}\text{u}$ ratio) and lipid conjugated diene absorbance at 233 nm indicated that the a_w of 0.33 and the storage temperature of 5°C were the most effective in mitigating the oxidation of the cowpea lipid.Oxidation rates of the unsaturated fatty acids were related to their levels of unsaturation.     

Fatty acids profile of oil from nine varieties of Macadamia nut

The fatty acids profile and lipids content of the Macadamia integrifolia and Macadamia tetraphylla varieties and interspecies hybrids, M. integrifolia and M. tetraphylla were analyzed. Total lipids content ranged from 70.9 to 79.7 g of oil per 100 g^?1 dry-solids. Gas chromatography/mass spectrophotometry identified 20 fatty acids, the most abundant of which were oleic acid (40 to 51%), palmitoleic acid (24 to 36%), and palmitic acid (8.4 to 13.1%). Fatty acids concentration differed between varieties and hybrids (Multivariate analysis of variance, F = 13.89, p < 0.0001). A ratio of monounsaturated fatty acids:saturated fatty acid values ranged from 2.8 to 4.6. The Huatusco variety (M. integrifolia and M. tetraphylla) exhibited the highest percentage of lipids (79.7 g of oil per 100 g^?1 DS) and the highest monounsaturated fatty acids:saturated fatty acid (4.6), thus highlighted its potential applications within the food industry. The Cate variety (M. integrifolia and M. tetraphylla) had the lowest monounsaturated fatty acids:saturated fatty acid, suggesting potential uses in the cosmetics industry.     

Fatty acid and lipid class composition of the eicosapentaenoic acid-producing microalga, Nitzschia laevis

The diatom Nitzschia laevis is a potential producer of eicosapentaenoic acid (EPA, C20:5n − 3). In order to further adopt this alga in the functional food and aquaculture industries, the lipid class composition and fatty acid distribution in the lipid pool of N. laevis were studied using thin-layer chromatography and gas chromatography. The total lipids of N. laevis were fractionated into neutral lipids (NLs), glycolipids (GLs) and phospholipids (PLs). NLs were the major constituents and accounted for 78.6% of the total lipids. Triacylglycerol (TAG) was the predominant component of NLs (87.9%). GLs and PLs accounted for 8.1% and 11.6% of the total lipids, respectively. Phosphatidylcholine (PC) was the major component of PLs (69.7%). The principal fatty acids identified in most lipid classes were tetradecanoic acid (C14:0), hexadecanoic acid (C16:0), palmitoleic acid (C16:1) and EPA. EPA was distributed widely among the various lipid classes with the major proportion (75.9% of the total EPA) existing in TAG, monoacylglycerol and PC.     

Variations in proximate composition and fatty acid profiles of Baltic sprat (Sprattus sprattus balticus)

The variability of the proximate composition and fatty acid profiles in samples of sprat (Sprattus sprattus balticus) from the southern Baltic Sea were studied in relation to the catch season and location, individual fish size, and sex. Fatty acid profiles depended on such features as fish size and lipid content, which depend on the season of the year in which the fish were caught. No differences in fatty acid profiles were noted between the sexes in the individuals examined. Studies on fish lipids are necessary as fish lipids are important in the prevention of cardiac disease. One of the chief advantages of fish lipids that is relevant to the prevention of cardiac disease is their n−3 to n−6 fatty acid ratio. The most advantageous ratio of these fatty acids was noted in sprat that were the smallest in length.     

Fatty acid composition and oxidative susceptibility of fresh loin and liver from pigs fed conjugated linoleic acid in combination with monounsaturated fatty acids

Three levels (0%, 1% and 2%) of conjugated linoleic acid (CLA) were combined with two levels of monounsaturated fatty acids (MUFA) (low: 19% and high: 39%) for pig feeding. The fatty acid profile of neutral lipids (NL) and polar lipids (PL) of loin and liver and their oxidative susceptibility were studied. A dose-dependent enrichment in cis-9, trans-11 CLA and trans-10, cis-12 CLA in NL and PL of loin and liver was obtained. This effect was independent of the MUFA supplementation (except for NL of loin in which the CLA accumulation was higher at high MUFA levels). Regardless of the MUFA supplementation, dietary CLA increased the ratio of saturated fatty acids (SFA) to unsaturated fatty acids in both tissues and lipid fractions. The interaction between CLA and MUFA affected the SFA and polyunsaturated fatty acids contents of PL from loin. Regardless of the MUFA level of the diets, CLA supplementation decreased the induced peroxidation values in liver and did not change those of loin.     

Characterization of Longissimus thoracis, Semitendinosus and Masseter muscles and relationships with technological quality in pigs. 2. Composition of muscles

The composition of three porcine muscles (Longissimus thoracis: LT, Semitendinosus: ST, Masseter: MS) was characterized and its link with muscle quality was evaluated. The LT muscle had a higher content of tyrosine, tryptophan, and carbohydrates and a lower content of vitamin E and haem iron than the MS muscle, while the ST had similar composition to MS but a lower content of haem iron. Large differences between muscles were observed in relative amounts of most of the major fatty acids. The LT muscle had higher saturated fatty acids (SFA) and n− 6:n− 3 fatty acid ratio, and lower polyunsaturated fatty acids (PUFA), PUFA:SFA ratio, unsaturation index and average fatty acid chain length than the ST and MS muscles. Muscle pH, redness and chroma were positively correlated with vitamin E and unsaturated lipids and negatively correlated with tyrosine, tryptophan, carbohydrates and saturated lipids, whereas muscle lightness and expressible juice showed similar correlations but an opposite sign with these variables.     

Fatty acid composition in some wild edible mushrooms growing in the middle Black Sea region of Turkey

The fatty acids in Agaricus bisporus, Agaricus campestris, Boletus edulis, Coprinus comatus, Pleurotus ostreatus, Oudemansiella radicata and Armillaria mellea species were obtained by a Soxtec system extracted with chloroform/methanol (2:1) and derivation of their methyl ester forms. The fatty acids were identified and quantified by gas chromatography. The fatty acid compositions mushrooms were studied using fruit body and stems. Fatty acid composition varied among species. The dominant fatty acid in fruit body and stem of all mushroom species was linoleic acid (18:2). Percentage of linoleic acid in species varied from 13% to 59%. Linoleic acid levels were higher in the stem of O. radicata than in the stems of other mushroom species. The other major fatty acids were, respectively, palmitic, oleic, stearic and arachidic acids. Linolenic acid levels were low in all species. Fatty acids analysis of the mushrooms showed that the unsaturated fatty acids were at higher concentrations than saturated fatty acids.     

Purification and identification of bovine cheese whey fatty acids exhibiting in vitro antifungal activity

Milk lipids contain several bioactive factors exhibiting antimicrobial activity against bacteria, viruses, and fungi. In the present study, we demonstrate that free fatty acids (FFA) derived from the saponification of bovine whey cream lipids are active in vitro at inhibiting the germination of Candida albicans, a morphological transition associated with pathogenicity. This activity was found to be significantly increased when bovine FFA were enriched in non-straight-chain FFA. At low cell density, this non-straight-chain FFA-enriched fraction was also found to inhibit in a dose-dependant manner the growth of both developmental forms of C. albicans as well as the growth of Aspergillus fumigatus. Using an assay-guided fractionation, the main components responsible for these activities were isolated. On the basis of mass spectroscopic and gas chromatographic analysis, antifungal compounds were identified as capric acid (C10:0), lauroleic acid (C12:1), 11-methyldodecanoic acid (iso-C13:0), myristoleic acid (C14:1n-5), and γ-linolenic acid (C18:3n-6). The most potent compound was γ-linolenic acid, with minimal inhibitory concentration values of 5.4 mg/L for C. albicans and 1.3 mg/L for A. fumigatus, in standardized conditions. The results of this study indicate that bovine whey contains bioactive fatty acids exhibiting antifungal activity in vitro against 2 important human fungal pathogens.     

Changes in lipids and their contribution to the taste of migaki-nishin (dried herring fillet) during drying

This study was conducted to investigate the changes in lipids and their effect on the taste of migaki-nishin during drying. Lipid was extracted from herring fillets following different drying stages to measure the degree of lipid oxidation and changes in lipid composition, and fatty acid profile. Peroxide value, carbonyl value and acid value of the lipids were significantly increased (P < 0.05) during the drying period. Marked increase in free fatty acids, with decreases in triglyceride and phospholipid content were observed in proportion to drying time and this result suggested that hydrolysis was induced by lipases and phospholipases. The decreases in polyunsaturated fatty acids (PUFAs), especially eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), were observed in the total lipids and phospholipid fraction. In addition, significant increase in PUFAs especially DHA was found in the free fatty acid fraction. Sensory evaluation showed that an addition of DHA to mentsuyu significantly (P < 0.05) enhances the intensities of thickness, mouthfulness and continuity. These results suggest that during drying period lipid oxidation was not only occurred but also lipolysis predominantly released DHA, which might have a contribution to kokumi enhancement of migaki-nishin.     

Direct quantification of fatty acids in dairy powders with special emphasis on trans fatty acid content

In this study a validated procedure for accurate determination of fatty acids in dairy products, with special emphasis on total trans fatty acids (TFA) content is presented. Dairy fat naturally contains 4–6% of trans fatty acids, mainly trans-octadecenoic acids (i.e. vaccenic acid), and 0.3–1.5% of conjugated linoleic acids (CLA). The proposed procedure does not require lipid extraction, and transesterification of lipids could be carried out directly on dairy products. Optimal analytical conditions have been developed to allow accurate determination of TFA content without prior fractionation of cis/trans FAME isomers by thin-layer chromatography. The methodology requires the use of a highly polar open tubular capillary column having at least 100 m length. CLA and other fatty acids from C4:0 (butyric) acid to long-chain polyunsaturated fatty acids (LC-PUFAs) could also be analyzed. Therefore, the methodology presented is versatile and could be used for both targeted analysis (e.g. determination of TFA in dairy products) and determination of the broad fatty acid profile in dairy products.     

Effect of selenium on lipid alternations in pigment-forming yeasts

The work deals with lipid modifications of pigment-forming yeasts Rhodotorula and Sporobolomyces growing under presence of selenium. This metal in the medium significantly prolonged lag-phase of all cultures and enlarged yeast cells. Total, neutral, and membrane yeast lipids (phosphatidylcholine, phosphatidylethanolamine, phosphatidylserine, and phosphatidylinositol) consisted of predominantly palmitic, palmitoleic, stearic, oleic, linoleic, and linolenic acids. Selenium activated fatty acid unsaturation mainly in phosphatidylcholine due to elevated levels of linoleic and linolenic acids. Because biosynthesis of C18 unsaturated fatty acids in Rhodotorula and Sporobolomyces species may be associated with phosphatidylcholine moieties, selenium might be involved to the induction of membranebound fatty acid Δ¹² and Δ¹⁵ desaturases in red yeasts. Oppositely, neutral lipids (primarily triacylglycerols) did not show such intensive changes in fatty acid composition as their polar counterparts. These observations could be applied for preparation of selenized red yeasts containing carotenoid pigments with enhanced accumulation of linoleic and linolenic acids.     

Quantification of Fatty Acid Methyl Esters in Various Biological Matrices by LC-DAD and LC-MS after One-Step Transesterification

The investigation of lipids is a complex field and many analytical methods are applied. Gas chromatography (GC) methods are the standard methods; however, GC systems are not available for every researcher. Hence, an alternative liquid chromatography (LC) method was designed. The LC method was developed and validated for separation of C16:n and C18:n fatty acid methyl esters (FAMEs). Baseline-separation of eight FAMEs was achieved with one C18 column. Two ways of detection (diode array detector, DAD, and mass spectrometry, MS), were established and compared. The validation results proved that the method is precise (RSD?<?10%), accurate (recovery rates 86–120%), and linear (R²?>?0.99) for all analysed FAMEs. Limits of detection (LOD) down to 3 ng and limits of quantification (LOQ) down to 6 ng were achieved. For sample preparation, a one-step transesterification method was used. In bacon fat, duckling lard, and butter, palmitic acid, stearic acid, and oleic acid were the main fatty acids. Olive oil had the highest oleic acid content (60% w/w). Linseed extract showed the highest linolenic acid content (60% w/w). In fungi extract, only a few fatty acids were detected. The highest fatty acid diversity was found in algae extract. Seven of the eight investigated fatty acids were found therein including C16 polyunsaturated fatty acids (PUFAs); further, uncommon C16 and C18 PUFAs were identified. In conclusion, the LC method with DAD detection represents a simple alternative to the usually used GC methods. Using MS detection, unknown compounds can be additionally identified and 10-fold lower LODs can be achieved.     

Chemical composition and DSC thermal properties of two species of Hylocereus cacti seed oil: Hylocereus undatus and Hylocereus polyrhizus

Two types of pitaya (Hylocereus cacti) seeds (Hylocereus undatus and Hylocereus polyrhizus) were investigated in this study. The fatty acid, phenolic, tocopherol, and sterol contents of the extracted seed oil were analysed. The results showed that the pitaya seeds contained a high amount of oil (18.33–28.37%). The three major fatty acids in the H. undatus seed oil (WFSO) and H. polyrhizus seed oil (RFSO) were linoleic, oleic, and palmitic acids. The total tocopherol contents in the WFSO and RFSO were 36.70 and 43.50 mg/100 g, respectively. The phytosterol compounds identified in the WFSO and RFSO were cholesterol, campesterol, stigmasterol, and β-sitosterol. Seven phenolic acid compounds were identified in the WFSO and RFSO, namely, gallic, vanillic, syringic, protocatechuic, p-hydroxybenzoic, p-coumaric, and caffeic acids. WFSO and RFSO can be differentiated by their T_off and T_on values in the DSC thermal curves. This study reveals that pitaya seed oil has a high level of functional lipids and can be used as a new source of essential oil.     

The fatty acid composition of the lipids of earthworms.

Lipids were freshly extracted from earthworms from agricultural pasture land, and fatty acid compositiona analyses were carried out on the total lipids; phospholipids; triglycerides; free fatty acids; mixed sterol esters, wax esters, free methyl esters, etc.; glycolipids; and neutrallipids. A wide variety of fatty acids ranging from C₁₀ to C₃₂ were identified. In the fatty acids of the total lipids, polyunsaturated constituents predominated in amount, while monomethyl branched, isoprenoid and n-odd-numbered acids were present in appreciable proportions. Eicosa-5,8,11,14,17-pentaenoic acid and arachidonic acid occurred at higher levels than any other components and were located mostly in the phospholipids. Significant contents of linoleic and linolenic acids were also detected. Earthworms collected in spring had a fatty acid composition which differed noticeably from that of worms from other seasons. The content of lauric acid during spring was much higher than that normally found in animals or pasture plants. The composition of the free fatty acids indicated that these components were the products of lipolysis and were derived from all the lipid classes. The results of this investigation suggest that the diet of local earthworms, which is reported to consist mainly of dead plant material, is supplemented by living and dead microorganisms from ingested soil.     

Bioactive lipids and fatty acids profile of Cistanche phelypaea

Oil extracted from the wild plant of Cistanche phelypaea was analyzed for its fatty acid, sterol, hydrocarbon and tocopherol contents. Total lipids (TL) content was 10?g/kg (on dry weight basis). The majority of fatty acids were of the unsaturated type (50.4?% of total fatty acids), while the saturated (mainly palmitic acid) were about 43.2?% of the total fatty acids. Oleic acid was the dominating fatty acid followed by palmitic and linoleic acids. High amounts of sterols were found in the oil with the main component ??-sitosterol. Other phytosterols (e.g. stigmasterol, ?⁷-avenasterol and ?⁵-avenasterol) were present at approximately equal amounts (6?C9?% of total sterols). The main identified hydrocarbon compounds were C₂₁, C₂₆ and C₃₂ constituting about 61.2?% of total hydrocarbons. Small amounts of C₁₂, C₁₈ and C₂₂, however, were also detected. Tocopherol levels were high in the oil (3.36?g/kg oil), wherein ??-tocopherol was the main component followed by ??-isomer. Both tocopherol components comprised more than 87?% of total vitamin E content in the oil. Furthermore, ??- and ??-tocopherols were detected in small amounts in the oil accounting for 14?C16?% of the total vitamin E content. Information provided by the present work will be of importance for food applications and chemotaxonomy of Cistanche phelypaea.     

Dietary linseed supplementation affects the fatty acid composition of the sn-2 position of triglycerides in sheep milk

In the human intestine, lipids are absorbed as sn-2 monoglycerides (sn-2, also named β-position), produced mainly by pancreatic lipases, which hydrolysate the triglyceride molecule in positions 1 and 3 (sn-1,3, α-position). The fatty acids esterified in sn-2 are thus preferentially absorbed, which means that the bioavailability of a single fatty acid is affected by its position on the triglyceride. This experiment is carried out with the milk used to make cheese applied in a study with 42 human volunteers. In that study the authors detected an improvement in the blood lipid profile. The aim of the present study was to examine the effectiveness of this kind of cheese in improving human health by studying how linseed supplementation affects the milk fatty acid composition of the 3 different triglyceride positions and thus the fatty acid bioavailability. The sn-2 were obtained by reacting total milk lipids with swine pancreatic lipase. The milk came from 24 sheep fed a control diet and 24 sheep fed a diet containing 200 g of extruded linseed per day. The sn-2 were separated by thin-layer chromatography. The fatty acid composition of total lipids and sn-2 was obtained by a gas chromatography-flame ionization detector apparatus equipped with a high polar 100 m length capillary column. The bioavailability of the fatty acids was evaluated by a putative preferential intestinal absorption index (PPIAi), where PPIAi <0 indicated a disadvantageous nutritional condition and PPIAi >0 indicated a preferential intestinal absorption. With regard to the fatty acid composition of triglycerides, the linseed group showed a significantly higher content of both linolenic acid and rumenic acid compared with the control. As a consequence of linseed supplementation, the linolenic and rumenic acid content esterified in the β-position increased greatly. This was highlighted by the PPIAi. The results of the present study suggest that the linolenic acid and conjugated linoleic acid affinity for lyso-phosphatidic acid acyl-transferase increased with its tissue availability.     

Chemical,amino acid and fatty acid composition of Sterculia urens L. seed

The chemical, amino acid and fatty acid compositions of Sterculia urens seeds are reported. The cotyledons were found to be rich in protein (30.88%) and lipids (39.2%). The major amino acids in defatted Sterculia urens cotyledon flour (DSCF) were determined as glutamic acid, arginine and aspartic acid. Cysteine, methionine, tyrosine and histidine were observed in minor quantities. The ratio of essential to non-essential amino acids was observed to be 0.45. Among the essential amino acids, isoleucine was found to be higher than the reported FAO/WHO requirements. The GC-FID and GC–MS analysis revealed that the major fatty acids of the total lipid were stearic acid (31.72%), linoleic acid (28.83%) and palmitic acid (26.79%). Eicosadienoic acid (4.98%) and eicosatrienoic acid (2.96%) were also found in the total lipid.     

Fatty acid distribution in triacylglycerols and phospholipids of broad beans (Vicia faba)

Fatty acid distribution of triacylglycerols (TAG) and phospholipids (PL) obtained from the four cultivars of broad beans (Vicia faba) was investigated. Total lipids extracted from the beans were separated by thin-layer chromatography into eight fractions. The major lipid components were TAG (47.7–50.1%) and PL (47.5–50.5%), while hydrocarbons, steryl esters, free fatty acids, diacylglycerols (1,3-DAG and 1,2-DAG) and monoacylglycerols were present in minor proportions (1.8–2.4%). The major PL components were phosphatidylcholine (56.4–58.4%), phosphatidylethanolamine (20.3–21.7%) and phosphatidylinositol (16.6–18.6%). Phosphatidylinositol was unique in that it had the highest saturated fatty acid content among the three PL. No significant differences (P > 0.05) in fatty acid distribution existed when the different cultivars were compared. The fatty acid distributions in the TAG were evident among the four cultivars: unsaturated fatty acids were predominantly concentrated in the sn−2 position, and saturated fatty acids primarily occupied the sn−1 or sn−3 position in the oils. These results could be useful to both consumers and producers for manufacture of traditional foods in Japan and elsewhere.     

Influence of season on the lipid content and fatty acid profiles of three tilapia species (Oreochromis niloticus,O. macrochir and Tilapia rendalli) from Madagascar

Lipids extracted from three tilapia species (Oreochromis niloticus, O. macrochir and Tilapia rendalli) of mean weight 100–250 g collected in Itasy lake of Madagascar highlands during three seasons, were analyzed for their fatty acid compositions. The muscle fishes contained less than 1.4% lipid by weight. Gas chromatography (GC) and gas chromatography–mass spectrometry (GC–MS), allowed identification of more than 40 fatty acids and 30 of them were quantified in muscle tissue lipids of fishes. Among them, those occurring in the highest proportions were palmitic, stearic, oleic, palmitoleic and linoleic acids. The main polyunsaturated fatty acids were arachidonic acid, eicosa-5,8,11,14,17-pentaenoic acid (EPA) and docosa-4,7,10,13,16,19-hexaenoic acid (DHA). The relative amount of these acids changed significantly between species and season of collect, in particular DHA which decreased from 11.4% to 6.0% for O. macrochir during the spring to autumn period. For O. niloticus and T. rendalli, DHA decreased from 9.8% to 4.9% and to 10.1% to 4.4%, respectively during the same period. Therefore the ∑n−3/∑n−6 ratios vary, for each species according to season of collect, being lower in autumn (0.5–0.6) and raising up to 0.7–1.6 in winter. Multivariate statistical analyses, starting from the fatty acid composition, lipid percentage and biometric ratio (weight/size) data of 113 samples, reveals significative differences between species and season of collect. Furthermore differences in fatty acid profiles are higher within season than species. The results show that wild tilapias from tropical lakes of the Madagascar highlands possess beneficial properties and therefore contribute significantly of the n−3 fatty acids intake of the local population diet.