Simultaneous Treatment of Long-chain Monounsaturated Fatty Acid and n-3 Polyunsaturated Fatty Acid Decreases Lipid and Cholesterol Levels in HepG2 Cell.

The n-3 type polyunsaturated fatty acids (n-3PUFAs), including eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), from fish oil exhibit health benefits such as triacylglycerol- and cholesterol-lowering effects. Some pelagic fishes contain long-chain monounsaturated fatty acids (LC-MUFAs) such as eicosenoic acid (C20:1), which exert health-promoting effects. However, no study has evaluated beneficial effects of n-3PUFA and LC-MUFA combination. Here, we investigated effects of simultaneous treatment with n-3PUFA (EPA and DHA) and LC-MUFA (cis-5-C20:1 and cis-7-C20:1) and found that n-3PUFA and LC-MUFA combination significantly decreased lipid accumulation and reduced total cholesterol in HepG2 cells. Cholesterol level was significantly lower in DHA + cis-7-C20:1 group than in DHA + EPA group. These results suggest the importance of LC-MUFA as a functional molecule in fish oil.

Pharmacological effects and mechanisms of muscone.

Musk, the dried secretion from the preputial follicles of the male musk deer (genus Moschus), possesses various pharmacological activities and has been used extensively in traditional Chinese medicine for thousands of years. Muscone is the main active ingredient of musk and exerts pharmacological effects similar to those of musk. Although muscone was notably used to treat various disorders and diseases, such as neurological disorders, chronic inflammation and ischemia-reperfusion injury, most of the mechanisms of the pharmacological action of muscone remain unclear because of slow progress in research before the 21st century. In recent years, the pharmacological activities and mechanisms of muscone have been clarified. The present article summarizes the pharmacological and biological studies on cerebrovascular disease, cardiovascular disease, neurological effects, cancer and others and the associated mechanisms of the action of muscone to date.

Proteome of thymus and spleen reveals that 10-hydroxydec-2-enoic acid could enhance immunity in mice.

Objectives: 10-hydroxydec-2-enoic acid (10-HDA), a unique component of royal jelly existing only in nature, has the potential to promote human health. Knowledge of 10-HDA in regulating immuno-activity, however, is lacking. The aim of our work is to gain a novel understanding of 10-HDA in promoting immunity.Methods: Immuno-suppressed mice were generated by cyclophosphamide injection, After 10-HDA supplementation to the mice to rescue their immunity, the proteomes of the thymus and spleen were analyzed.Results: The weight of the body, thymus, and spleen in cyclophosphamide-induced mice recovered by 10-HDA indicate its potential role in immuno-organ protection. In the thymus, the enhanced activity of pathways associated with DNA/RNA/protein activities may be critical for T-lymphocyte proliferation/differentiation, and cytotoxicity. In the spleen, the induced pathways involved in DNA/RNA/protein activities, and cell proliferative stimulation suggest their vital role in B-lymphocyte affinity maturation, antigen presentation, and macrophage activity. The up-regulated proteins highly connected in networks modulated by 10-HDA indicate that the mice may evolve tactics to respond to immuno-organ impairment by activating critical physiological processes.Conclusion: Our data constitute a proof-of-concept that 10-HDA is a potential agent to improve immunity in the thymus and spleen and offer a new venue for applying natural products to the therapy for hypoimmunity.

Trans-palmitoleic acid (trans-9-C16:1, or trans-C16:1 n-7): Nutritional impacts, metabolism, origin, compositional data, analytical methods and chemical synthesis. A review.

Since the early 2010s, dietary trans-palmitoleic acid (trans-9-hexadecenoic acid, trans-9-C16:1 in the Δ-nomenclature, trans-C16:1 n-7 in the Ω-nomenclature, TPA) has been epidemiologically associated with a lower risk of type 2 diabetes in humans. Thanks to these findings, TPA has become a nutrient of interest. However, there is a lot of unresolved crucial questions about this dietary fatty acid. Is TPA a natural trans fatty acid? What kind of foods ensures intakes in TPA? What about its metabolism? How does dietary TPA act to prevent type 2 diabetes? What are the biological mechanisms involved in this physiological effect? Clearly, it is high time to answer all these questions with the very first review specifically dedicated to this intriguing fatty acid. Aiming at getting an overview, we shall try to give an answer to all these questions, relying on appropriate and accurate scientific results. Briefly, this review underlines that TPA is indeed a natural trans fatty acid which is metabolically linked to other well-known natural trans fatty acids. Knowledge on physiological impacts of dietary TPA is limited so far to epidemiological data, awaiting for supplementation studies. In this multidisciplinary review, we also emphasize on methodological topics related to TPA, particularly when it comes to the quantification of TPA in foods and human plasma. As a conclusion, we highlight promising health benefits of dietary TPA; however, there is a strong lack in well-designed studies in both the nutritional and the analytical area.

In Silico, Cytotoxic and Antioxidant Potential of Novel Ester, 3-hydroxyoctyl -5- trans-docosenoate Isolated from Anchusa arvensis (L.) M.Bieb. Against HepG-2 Cancer Cells.

BACKGROUND: Cancer is one of the chronic health conditions worldwide. Various therapeutically active compounds from medicinal plants were the current focus of this research in order to uncover a treatment regimen for cancer. Anchusa arvensis (A. anchusa) (L.) M.Bieb. contains many biologically active compounds. METHODS: In the current study, new ester 3-hydroxyoctyl -5- trans-docosenoate (compound-1) was isolated from the chloroform soluble fraction of A. anchusa using column chromatography. Using MTT assay, the anticancer effect of the compound was determined in human hepatocellular carcinoma cells (HepG-2) compared with normal epithelial cell line (Vero). DPPH and ABTS radical scavenging assays were performed to assess the antioxidant potential. The Molecular Operating Environment (MOE-2016) tool was used against tyrosine kinase. RESULTS: The structure of the compound was elucidated based on IR, EI, and NMR spectroscopy technique. It exhibited a considerable cytotoxic effect against HepG-2 cell lines with IC50 value of 6.50 ± 0.70 µg/mL in comparison to positive control (doxorubicin) which showed IC50 value of 1.3±0.21 µg/mL. The compound did not show a cytotoxic effect against normal epithelial cell line (Vero). The compound also exhibited significant DPHH scavenging ability with IC50 value of 12 ± 0.80 µg/mL, whereas ascorbic acid, used as positive control, demonstrated activity with IC50 = 05 ± 0.15 µg/mL. Similarly, it showed ABTS radical scavenging ability (IC50 = 130 ± 0.20 µg/mL) compared with the value obtained for ascorbic acid (06 ± 0.85 µg/mL). In docking studies using MOE-2016 tool, it was observed that compound-1 was highly bound to tyrosine kinase by having two hydrogen bonds at the hinge region. This good bonding network by the compound might be one of the reasons for showing significant activity against this enzyme. CONCLUSION: Our findings led to the isolation of a new compound from A. anchusa which has significant cytotoxic activity against HepG-2 cell lines with marked antioxidant potential.

A mini review of nervonic acid: Source, production, and biological functions.

Nervonic acid (NA) has attracted considerable attention because of its close relationship with brain development. Sources of NA include oil crop seeds, oil-producing microalgae, and other microorganisms. Transgenic technology has also been applied to improve the sources and production of NA. NA can be separated and purified by urea adduction fractionation, molecular distillation, and crystallization. Studies on NA functionality involved treatments for demyelinating diseases and acquired immunodeficiency syndrome, as well as prediction of mortality due to cardiovascular diseases and chronic kidney disease. This mini review focuses on the sources, production, and biological functions of NA and provides prospective trends in the investigation of NA.

Tandem Mass Tag Based Quantitative Proteomics of Developing Sea Buckthorn Berries Reveals Candidate Proteins Related to Lipid Metabolism.

Sea buckthorn ( Hippophae L.) is an economically important shrub or small tree distributed in Eurasia. Most of its well-recognized medicinal and nutraceutical products are derived from its berry oil, which is rich in monounsaturated omega-7 (C16:1) fatty acid and polyunsaturated omega-6 (C18:2) and omega-3 (C18:3) fatty acids. In this study, tandem mass tags (TMT)-based quantitative analysis was used to investigate protein profiles of lipid metabolism in sea buckthorn berries harvested 30, 50, and 70 days after flowering. In total, 8626 proteins were identified, 6170 of which were quantified. Deep analysis results for the proteins identified and related pathways revealed initial fatty acid accumulation during whole-berry development. The abundance of most key enzymes involved in fatty acid and triacylglycerol (TAG) biosynthesis peaked at 50 days after flowering, but TAG synthesis through the PDAT (phospholipid: diacylglycerol acyltransferase) pathway mostly occurred early in berry development. In addition, the patterns of proteins involved in lipid metabolism were confirmed by combined quantitative real-time polymerase chain reaction, enzyme-linked immunosorbent assay, and parallel reaction monitoring analyses. Our data on the proteomic spectrum of sea buckthorn berries provide a scientific basic for understanding lipid metabolism and related pathways in the developing berries.

Bioassay-guided isolation of active anti-adipogenic compound from royal jelly and the study of possible mechanisms.

BACKGROUND: Royal jelly (RJ) has been used traditionally for dietary, cosmetic and health purposes for a long time in different parts of the world. Scientific studies have also shown its numerous health-promoting properties including hypoglycemic and anti-hypercholesterolemic action. In this study, we investigated the anti-adipogenic activity of RJ in 3 T3-L1 cells and isolated the major responsible root component for the activity. METHODS: An active anti-adipogenic compound was isolated through bioassay-guided isolation process by successive treatment of RJ and its active fractions on 3 T3-L1 cell line. (E)-10-Hydroxy-2-decenoic Acid (10-HDA) was identified using NMR spectroscopy and ultra-performance liquid chromatography (UPLC). As 10-HDA showed significant anti-adipogenic activity with Oil Red O staining and TG content assay on 3 T3-L1 adipocytes, further study was carried out in molecular level for the expression of adipogenic transcription factors such as PPARγ, FABP4, C/EBPα, SREBP-1c, and Leptin. The effect of 10-HDA on preliminary molecules such as pAkt, pERK, C/EBPß, and pCREB were studied in the early stage of adipogenesis. The effect of 10-HDA on reactive oxygen species (ROS) production in fully differentiating adipocytes was measured by nitro blue tetrazolium (NBT) assay. RESULT: Results showed that triacylglycerol accumulation and ROS production was markedly suppressed by 10-HDA. Preliminary molecules such as pAkt, pERK, pCERB, and C/EBPß were found to be down-regulated by 10-HDA, which led to down-regulation of key adipogenic transcription factors such as PPARγ, FABP4, CEBPα, SREBP-1c, and Leptin on 3 T3-L1 adipocytes. CONCLUSION: Our results suggest that anti-adipogenesis of 10-HDA on 3 T3-L1 adipocyte takes place via two mechanisms: inhibition of cAMP/PKA pathway and inhibition of p-Akt and MAPK dependent insulin signaling pathway. So it is considered that 10-HDA, a major component of RJ, can be a potential therapeutic medicine for obesity.

Effects of climate on fatty acid profile in Camelina sativa.

Due to the importance of Camelina for low expectation (water and other inputs) and as an oil crop, Soheil cultivar was cultivated in Ardebil, Hamedan, Rasht, Ilam, Kermanshah, Karaj, Mashhad, Ahvaz and Bushehr Provinces. Fatty acids were measured with MG-Mass. Results showed that morphological traits were not very dependent on the climate, but the profile of the fatty acids was dependent. ANOVA of the effects of climate on the saturated fatty acid showed that there were significant differences between climates for all studied SFAs (P<0.01) with the exception of Lauric acid. Mean squares of the effects of climate on the Unsaturated Fatty Acids (MUFA) in showing that there were significant differences between climates for all studied MUFAs (P<0.01). Mean squares of the effects of climate on the amount of polyunsaturated fatty acids (PUFA), oil percentage and protein content of seeds indicated that there were significant differences between climates for all these studied traits. Mean squares of the effects of climate on the amount of polyunsaturated fatty acids (PUFA), oil percentage and protein content of seeds indicated that there were significant differences between climates for all these studied traits. The statistical analysis for the effects of Climate on the ratio of the Saturated Fatty Acid (SFA) in Camelina sativa showed that there were significant differences (P<0.01) for SFA, MUSFA, PUFA, MP, P:S and MP:S. Briefly, in the cold climates, the percentage of unsaturated fatty acids was higher. So it is possible to the cultivation of this plant in cold provinces for nutritional purposes and in tropical provinces for industrial and sanitary purposes.

Ultrasound induced green solvent extraction of oil from oleaginous seeds.

Ultrasound-assisted extraction of rapeseed oil was investigated and compared with conventional extraction for energy efficiency, throughput time, extraction yield, cleanness, processing cost and product quality. A multivariate study enabled us to define optimal parameters (7.7 W/cm(2) for ultrasonic power intensity, 40 °C for processing temperature, and a solid/liquid ratio of 1/15) for ultrasound-assisted extraction of oil from oilseeds to maximize lipid yield while reducing solvent consumption and extraction time using response surface methodology (RSM) with a three-variable central composite design (CCD). A significant difference in oil quality was noted under the conditions of the initial ultrasound extraction, which was later avoided using ultrasound in the absence of oxygen. Three concepts of multistage cross-current extraction were investigated and compared: conventional multistage maceration, ultrasound-assisted maceration and a combination, to assess the positive impact of using ultrasound on the seed oil extraction process. The study concludes that ultrasound-assisted extraction of oil is likely to reduce both economic and ecological impacts of the process in the fat and oil industry.

Chemical composition of volatile and fixed oils from of Salvia argentea L. (Lamiaceae) growing wild in Sicily.

The chemical compositions of the essential oil and of the non-polar extracts (petroleum ether, dichloromethane) of the aerial parts (flowers, leaves and stems) of Salvia argentea L. were determined by GC-FID and gas chromatography-mass spectrometry analysis. 14-Hydroxy-α-humulene (40.1%) was recognised as the main constituents of the essential oil of S. argentea, together with 1,3,8-p-menthatriene (12.1%), globulol (7.4%) and ß-sesquiphellandrene (5.8%). Tritriacontane (9.9% and 14.1%), heptacosane (8.4% and 10.5%), hentriacontane (8.3% and 10.9%), tetradecanal (8.4% and 10.2%) and methyldotriacontane (7.9% and 7.6%) were recognised as the main constituents of the extracts in petroleum ether and dichloromethane, respectively, whereas methyl linolenate (36.6% and 13.5%) and methyl myristoleate (10.5% and 18.5%) were recognised as the main constituents of the methylated extracts.

Growth inhibition of Candida species by Wickerhamomyces anomalus mycocin and a lactone compound of Aureobasidium pullulans.

BACKGROUND: The increasing resistance of Candida yeasts towards antifungal compounds and the limited choice of therapeutic drugs have spurred great interest amongst the scientific community to search for alternative anti-Candida compounds. Mycocins and fungal metabolites have been reported to have the potential for treatment of fungal infections. In this study, the growth inhibition of Candida species by a mycocin produced by Wickerhamomyces anomalus and a lactone compound from Aureobasidium pullulans were investigated. METHODS: Mycocin was purified from the culture supernatant of an environmental isolate of W. anomalus using Sephadex G-75 gel filtration column chromatography. The mycocin preparation was subjected to SDS-PAGE analysis followed by MALDI TOF/TOF mass spectrometry analysis. The thermal and temperature stability of the mycocin were determined. The glucanase activity of the mycocin was investigated by substrate staining of the mycocin with 4-methyl-umbelliferyl-ß-D-glucoside (MUG). Gas chromatography mass spectrometry (GCMS) analysis was used to identify anti-Candida metabolite in the culture supernatant of an environmental isolate of Aureobasidium pullulans. The inhibitory effects of the anti-Candida compound against planktonic and biofilm cultures of various Candida species were determined using broth microdilution and biofilm quantitation methods. RESULTS: A mycocin active against Candida mesorugosa but not C. albicans, C. parapsilosis and C. krusei was isolated from the culture supernatant of W. anomalus in this study. The mycocin, identified as exo-ß-1,3 glucanase by MALDI TOF/TOF mass spectrometry, was stable at pH 3-6 and temperature ranging from 4-37°C. The glucanase activity of the mycocin was confirmed by substrate staining with MUG. 5-hydroxy-2-decenoic acid lactone (HDCL) was identified from the culture supernatant of A. pullulans. Using a commercial source of HDCL, the planktonic and biofilm MICs of HDCL against various Candida species were determined in this study. CONCLUSIONS: W. anomalus mycocin demonstrated a narrow spectrum of activity targeting only against C. mesorugosa, while HDCL demonstrated a broad spectrum of inhibitory action against multiple Candida species. The growth inhibition of W. anomalus mycocin and the lactone compound from A. pullulans against Candida yeasts should be further explored for therapeutic potentials against candidiasis.

Three new compounds from Dictamnus dasycarpus.

Phytochemical investigation of the ethyl acetate extracts from root barks of Dictamnus dasycarpus led to the isolation of three new compounds, named as dasycarpusenester A (1), dasycarpusester B (2), dasycarpusacid (3). Their structures were elucidated as (2S)-4-(2,2-dimethyl-5-oxotetrahydrofuran-3-yl)-2-hydroxypent-3-enoic acid methyl ester (1), (2R)-4-(2,2-dimethyl-5-oxotetrahydrofuran-3-yl)-2-hydroxypent-3-anoic acid methyl ester (2), and (2S)-4-(2,2-dimethyl-5-oxotetrahydrofuran-3-yl)-2-hydroxypent-3-anoic acid (3), respectively, on the basis of modern spectroscopic methods and chemical analysis.

Separation characteristics of fatty acid methyl esters using SLB-IL111, a new ionic liquid coated capillary gas chromatographic column.

The ionic liquid SLB-IL111 column, available from Supelco Inc., is a novel fused capillary gas chromatography (GC) column capable of providing enhanced separations of fatty acid methyl esters (FAMEs) compared to the highly polar cyanopropyl siloxane columns currently recommended for the separation of cis- and trans isomers of fatty acids (FAs), and marketed as SP-2560 and CP-Sil 88. The SLB-IL111 column was operated isothermal at 168°C, with hydrogen as carrier gas at 1.0 mL/min, and the elution profile was characterized using authentic GC standards and synthetic mono-unsaturated fatty acids (MUFAs) and conjugated linoleic acid (CLA) isomers as test mixtures. The SLB-IL111 column provided an improved separation of cis- and trans-18:1 and cis/trans CLA isomers. This is the first direct GC separation of c9,t11- from t7,c9-CLA, and t15-18:1 from c9-18:1, both of which previously required complimentary techniques for their analysis using cyanopropyl siloxane columns. The SLB-IL111 column also provided partial resolution of t13/t14-18:1, c8- from c6/c7-18:1, and for several t,t-CLA isomer pairs. This column also provided elution profiles of the geometric and positional isomers of the 16:1, 20:1 and 18:3 FAMEs that were complementary to those obtained using the cyanopropyl siloxane columns. However, on the SLB-IL111 column the saturated FAs eluted between the cis- and trans MUFAs unlike cyanopropyl siloxane columns that gave a clear separation of most saturated FAs. These differences in elution pattern can be exploited to obtain a more complete analysis of complex lipid mixtures present in ruminant fats.

Effects of mixing energy on the sedimentation of vegetable oil spills by clay.

The effects of clay dose and mixing energy on the efficiency of vegetable oil sedimentation by clay are investigated. The sedimentation efficiency increased with increasing clay dose to a maximum of about 80% of added oil. The maximum sedimentation efficiency was achieved at a lower clay dose, and the sedimentation efficiency was greater for a given clay dose when the oil was present as a thick oil film rather than as a thinner film. Sedimentation efficiency was relatively constant for mixing energies less than about 0.01 m2 s(-3) (0.01 W kg(-1)) but decreased dramatically at higher energy dissipation rates. Mixing energy may not be an important factor in determining the effectiveness of this response alternative because energy dissipation rates in natural surface water bodies under most typical conditions are less than 0.01 m2 s(-3). The effects of oil film thickness and mixing energy on the efficiency of vegetable oil sedimentation suggests that vegetable oil-mineral aggregates (VOMA) form through a different mechanism to that of petroleum oil-mineral aggregates (OMA). One consequence of the different formation mechanisms is that VOMA are much larger than petroleum OMA.

Rapid approach to biobased telechelics through two one-pot thiol-ene click reactions.

The application of environmentally friendly thiol-ene chemistry to the preparation of biobased telechelics is presented in this work. This methodology is based on two one-pot photoinitiated thiol-ene click processes: step-growth polymerization using a 3,6-dioxa-1,8-octanedithiol and end-group postpolymerization modification with three functional thiols: 2-mercaptoethanol, 3-mercaptopropionic acid, and 3-mercaptopropyltrimethoxysilane. We applied this approach to a potentially 100% biomass-derived monomer, allyl ester of 10-undecenoic acid (UDA). To show the generality and scope of this methodology, a series of well-defined telechelics with molecular weight ranging from 1000-3000 g/mol and hydroxyl, carboxyl, or trimethoxysilyl groups at the polymer terminus were prepared. An exhaustive (1)H NMR and MALDI-TOF MS analyses demonstrates the highly end-group fidelity of this methodology being an interesting procedure for the accelerated preparation of telechelics derived from divinyl monomers. UDA-based thelechelic diol prepared using this methodology was reacted with 4,4'-methylenebis(phenylisocyanate) and 1,4-butanediol as the chain extender to obtain multiblock poly(ester urethane).

Hydroxy monounsaturated fatty acids as agonists for peroxisome proliferator-activated receptors.

The physiological and pathological role of oxidized polyunsaturated fatty acids (PUFAs) has been extensively studied, whereas those of hydroxy monounsaturated fatty acids (MUFAs) are not well understood. This study demonstrated that 11-hydroxy-(9Z)-octadecenoic acid ((9Z)-11-HOE), which was isolated from adlay seeds (Coix lacryma-jobi L. var. ma-yuen STAF.), can activate peroxisome proliferator-activated receptor (PPAR)alpha, delta and gamma in luciferase reporter assays more efficiently than (9Z)-octadecenoic acid (oleic acid), and to the same degree as linoleic acid. (9Z)-11-HOE increased the mRNA levels of UCP2 and CD36 in C2C12 myotubes and THP- 1 cells, respectively, and these effects were blocked by the PPARdelta- and gamma-specific antagonists GSK0660 and T0070907, respectively. Evaluation of the structure.activity relationship between hydroxy MUFAs and PPAR activation revealed that (9E)-11-HOE, the geometrical isomer of (9Z)-11-HOE, activated PPARs more potently than (9Z)-11-HOE, and that PPAR activation by hydroxyl MUFAs was not markedly influenced by the position of the hydroxy group or the double bond, although PPARdelta seemed to possess ligand specificity different to that of PPARalpha or gamma . Additionally, the finding that 11-hydroxy octadecanoic acid, the hydrogenated product of (9E)-11- HOE, was also capable of activating PPARs to a similar extent as (9E)-11-HOE indicates that the double bond in hydroxy MUFAs is not essential for PPAR activation. In conclusion, (9Z)-11-HOE derived from alday seeds and hydroxy MUFAs with a chain length of 16 or 18 acted as PPAR agonists. Hydroxylation of MUFAs may change these compounds from silent PPAR ligands to active PPAR agonists.

Removal of emulsified food and mineral oils from wastewater using surfactant modified barley straw.

Barley straw, an agricultural waste, was chemically modified and evaluated for the removal of emulsified oils from aqueous solution. The chemical modification was performed using NaOH and a cationic surfactant, hexadecylpyridinium chloride monohydrate (CPC). The surface textural and chemical properties of the surfactant modified barley straw (BMBS) were characterized by N(2) adsorption, FT-IR, SEM and water soluble mineral content. The adsorption tests were carried out in batch adsorption system for removal of standard mineral oil (SMO) and canola oil (CO) from water. For both emulsified oils in wastewater, adsorption was found to be strongly related with solution pH. The isotherm study indicated that emulsified oil adsorption on BMBS could be fitted well with the Langmuir model other than Freundlich model. The maximum adsorption capacity for CO and SMO at 25 degrees C determined from the Langmuir isotherm is 613.3 and 584.2 mg g(-1), respectively. Desorption tests in water solution show that oil is strongly bonded with adsorbent and desorption is only about 1-2% in 24 h.

Quantitation of cis- and trans-monounsaturated fatty acids in dairy products and cod liver oil by mass spectrometry in the selected ion monitoring mode.

Monounsaturated fatty acids (MUFAs) are important constituents of dietary fats. While cis-configurated isomers belong to the classic fatty acids of food, trans-fatty acids are suspected to pose a risk to human health. In either case, a thorough assessment of both positional and geometrical isomers of MUFAs is an important task in food and life sciences. For this purpose, a method suitable for routine analysis was developed. After lipid extraction and conversion of fatty acids into corresponding fatty acid methyl esters, cis and trans isomers of MUFAs were separated on silver-ion-impregnated cartridges. Fractions containing either cis- or trans-MUFAs were determined by gas chromatography-electron ionization mass spectrometry in the selected ion monitoring (GC/EI-MS-SIM) mode using [M-32](+) as quantification ions and [M-74](+) as well as M(+) as qualifier ions. A total of 14 MUFAs were available as reference standards, but a total of 40 MUFAs (22 cis and 18 trans isomers) were identified with high selectivity in samples of cheese, goat fat, human milk, and cod liver oil. The 18:1 and 16:1 isomers contributed most to both the cis- and trans-MUFAs. Application of internal standards allowed for the quantification of MUFAs only in the food samples. The amount of trans-fatty acids was determined to be 0.9- 4.3 g/100 g, with the lowest levels in human milk fat and the highest levels in Roquefort cheese. After exclusion of oleic acid, the concentrations of trans- and cis-MUFAs were at the same level in samples from ruminants and human milk fat.