Fatty Acid Composition Of Triglycerides Research Articles

Catalytic conversion of triglycerides into diesel, jet fuel, and lube base oil

The conversion of biomass into sustainable fuels and chemicals is essential for addressing environmental concerns, reducing the carbon footprint of the energy sector, enhancing energy security, and promoting economic and social development. Among various biomass feedstocks, triglycerides from diverse sources, such as vegetable oils, animal fats, and microalgal oils, are particularly suitable for producing sustainable hydrocarbon fuels and chemicals due to their low oxygen contents and highly paraffinic backbone in the fatty acid units, the structures of which are already quite similar to those of petroleum-derived hydrocarbons. This implies that relatively simple catalytic conversions can effectively convert triglycerides into hydrocarbon products. In this Perspective, we will provide an overview on the hydroconversion of triglycerides into oxygen-free fuels, such as diesel and jet fuel, and value-added products such as lube base oil. In addition, we will discuss the important structural properties of the required catalysts and the effects of different fatty acid compositions of triglycerides for each conversion process in light of reaction mechanisms.

Intravascular hemolysis triggers NAFLD characterized by a deregulation of lipid metabolism and lipophagy blockade.

Intravascular hemolysis is a common feature of different clinical entities, including sickle cell disease and malaria. Chronic hemolytic disorders are associated with hepatic damage; however, it is unknown whether heme disturbs lipid metabolism and promotes liver steatosis, thereby favoring the progression to nonalcoholic fatty liver disease (NAFLD). Using an experimental model of acute intravascular hemolysis, we report here the presence of liver injury in association with microvesicular lipid droplet deposition. Hemolysis promoted serum hyperlipidemia and altered intrahepatic triglyceride fatty acid composition, with increments in oleic, palmitoleic, and palmitic acids. These findings were related to augmented expression of transporters involved in fatty acid uptake (CD36 and MSR1) and deregulation of LDL transport, as demonstrated by decreased levels of LDL receptor and increased PCSK9 expression. Hemolysis also upregulated hepatic enzymes associated with cholesterol biosynthesis (SREBP2, HMGC1, LCAT, SOAT1) and transcription factors regulating lipid metabolism (SREBP1). Increased LC3II/LC3I ratio and p62/SQSTM1 protein levels were reported in mice with intravascular hemolysis and hepatocytes stimulated with heme, indicating a blockade of lipophagy. In cultured hepatocytes, cell pretreatment with the autophagy inductor rapamycin diminished heme-mediated toxicity and accumulation of lipid droplets. In conclusion, intravascular hemolysis enhances liver damage by exacerbating lipid accumulation and blocking the lipophagy pathway, thereby promoting NAFLD. These new findings have a high translational potential as a novel NAFLD-promoting mechanism in individuals suffering from severe hemolysis episodes. © 2023 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.

Responses of the Macroalga Ulva prolifera Müller to Ocean Acidification Revealed by Complementary NMR- and MS-Based Omics Approaches.

Ocean acidification (OA) is a dramatic perturbation of seawater environments due to increasing anthropogenic emissions of CO2. Several studies indicated that OA frequently induces marine biota stress and a reduction of biodiversity. Here, we adopted the macroalga Ulva prolifera as a model and applied a complementary multi-omics approach to investigate the metabolic profiles under normal and acidified conditions. Our results show that U. prolifera grows at higher rates in acidified environments. Consistently, we observed lower sucrose and phosphocreatine concentrations in response to a higher demand of energy for growth and a higher availability of essential amino acids, likely related to increased protein biosynthesis. In addition, pathways leading to signaling and deterrent compounds appeared perturbed. Finally, a remarkable shift was observed here for the first time in the fatty acid composition of triglycerides, with a decrease in the relative abundance of PUFAs towards an appreciable increase of palmitic acid, thus suggesting a remodeling in lipid biosynthesis. Overall, our studies revealed modulation of several biosynthetic pathways under OA conditions in which, besides the possible effects on the marine ecosystem, the metabolic changes of the alga should be taken into account considering its potential nutraceutical applications.

A Mediterranean Meal Plan Modulates Fatty Acid Content of Human Milk in Women With Obesity

ObjectivesHuman milk (HM) fatty acid content is, influenced by both maternal adiposity and diet. The objective of this study was to determine the impact of a Mediterranean meal plan on HM fatty acid content in women with obesity.MethodsIn this pilot study, thirteen women with obesity (body mass index (BMI) ≥ 30 kg/m2) enrolled at five months post-partum and were provided a Mediterranean meal plan for four weeks. Nutrition Data System for Research was used to assess participants’ diet during the study. HM was collected at baseline and after the 4-week intervention. Cytokines were measured using multi-spot assays and the fatty acid composition of triglycerides determined using a UHPLC electrospray ionization mass spectrometry. Triglycerides containing a particular fatty acid species were normalized to the total abundance of all triglyceride species detected in each sample. Wilcoxon signed-rank tests were used to assess changes in participant diet and HM composition, and repeated measures correlations were used to test associations of paired measures. Summary statistics are presented as mean ± standard deviation.ResultsDuring the intervention, the ratio of the maternal intake of ω6 and ω3 fatty acids (ω6: ω3) significantly decreased (8.86 ± 1.60 vs. 4.63 ± 1.25, P < 0.001) and was positively correlated with HM levels of leptin and tumor necrosis factor-α (r = 0.64, p = 0.024 and r = 0.67, p = 0.017, respectively). Levels of human milk 20:3 (0.588 ± 0.085% vs. 0.483 ± 0.080%, P < 0.001) and 22:4 (0.057 ± 0.012% vs. 0.050 ± 0.011%, p = 0.01) fatty acids were significantly decreased following the intervention. Maternal intake of ω6: ω3 positively correlated with HM 20:3 and 22:4 fatty acid concentrations (r = 0.78, p = 0.001 and r = 0.71, p = 0.005, respectively).ConclusionsA 4-week Mediterranean meal plan modulated the fatty acid content in HM from women with obesity. There was an association between maternal ω6: ω3 intake and HM fatty acid content, supporting a role for maternal diet in modulating HM composition. Future studies are needed to investigate the effect of the intervention on specific fatty acids and whether the observed changes in HM impact infant growth or development.Funding SourcesUSDA ARS #6026–51,000-010–05S and #6026–51,000-012–06S, NIH/NIDDK R01DK107516, Arkansas Children's Research Institute/Arkansas Biosciences Institute GR037121.

Micro-engineering based Structuring and Valorization of Lipid Foods

Microengineering-based structuring and valorization of lipid foods were investigated. First, to control the fatty acid composition of triglycerides, modified lipases were prepared using emulsifiers and fatty acids, and applied to interesterification of fats and oils. Stearic acid was suitable for lipase activation, showing high interesterification activity. The structure of stearic acid-modified lipase was first analyzed by small-angle X-ray scattering. Next, the membrane separation performance for crude oil was investigated using hydrophobic non-porous membranes. Degumming and decolorization tests for crude soybean oil were conducted, revealing that the rejection of phospholipids and the decolorization ratio were more than 95%, representing higher quality compared to conventional methods. Membrane application to used edible oil also showed better performance than the conventional adsorption method. For practical use, improvement of the permeate flux is needed. Finally, a technology was developed for preparing monodisperse emulsions using fabricated microchannels (MCs). Efficient emulsification was achieved using asymmetrically structured MCs. The slit structure caused large distortion of the oil-water interface, and the interfacial tension induced spontaneous droplet formation. Laboratory-scale MC emulsification equipment was industrialized and used for various applications.

Polyploidy affects fillet yield, composition, and fatty acid profile in two-year old, female rainbow trout, Oncorhynchus mykiss

Gonadal development in fish is a dominant physiological process that alters growth and fat metabolism, thereby affecting fillet quality. Sterile, triploid (3 N) female rainbow trout are generated by pressure-induced shock of zygotes (3NP), and by crossing a diploid (2 N; fertile) female and a tetraploid (4 N; fertile) male to produce triploid offspring 100% of the time (3NC; sterile). We have shown female intercross-triploids (3NC) have faster growth rates than pressure-induced triploids (3NP). Using a subset of these animals, we examined fillet yield, texture and fatty acid composition; additionally, fatty acid composition of triglycerides and phospholipids was determined. Variables were measured immediately prior to ovulation of (2 N; fertile) animals. Separable muscle as a percent of whole body weight was higher (P ≤ 0.05) in 3NC (46.5%) compared with 3NP (43.6%) fish, and both had higher yields than 2 N (38.3%) individuals. Fillets from 3NC fillets contained more (P ≤ 0.05) intramuscular crude fat than 3NP and 2 N fillets (13.4%, 11.2%, 8.17%, respectively). Also, 2 N fillets contained (P ≤ 0.05) fewer total saturated fatty acids (29.2%) compared to 3NP (33.4%) fillets which in turn, had fewer than 3NC (34.9%) fillets; suggesting diploids that stored SFA were used for egg development. Although 2 N fillets contained more (P ≤ 0.05) total polyunsaturated fatty acids relative to all fatty acids (PUFA, 28.7%) than 3NC and 3NP fillets (23.6% and 24.8%, respectively), the 3NC had the highest concentration per gram of fillet. 3NC and 3NP muscle had higher (P ≤ 0.05) levels of C12:0, C14:0, compared to 2 N. Fatty acids, C16:0 and 16:1, were highest (P ≤ 0.05) in 3NC, and 2 N muscle contained more (P ≤ 0.05) C22:6n3, C20:3n6 and C18:1n9c compared to 3NC and 3NP. Linoleic acid (18:2n6c) was highest in 2 N followed by 3NP and 3NC muscle (P ≤ 0.05). Thin Layer Chromatography plates were used to separate lipid classes and to evaluate the fatty acid composition of each lipid class. Ploidy did not affect (P > 0.05) fatty acids present in triglyceride and phospholipids. Albeit, triglycerides had higher (P ≤ 0.10) levels of C16:1, C18:1n9c, C18:2n6c, C18:3n3 and C22:1n9 compared to the phospholipids; whereas phospholipids contained higher levels of C16:0, C20:4n6, C20:5n3, and C22:6n3. Notably, phospholipids contained 3 times more C22:6n3 docosahexaenoic acid (DHA) compared to triglycerides. Overall, intercross-triploids (3NC) exhibited superior growth and fillet yields and higher concentrations of intramuscular crude fat compared to 3NP and 2 N females, fillet texture and fatty acid profile were not different, with the exceptions of C18:2n6c, C16:0, and C16:1.

Composition analysis of fatty acids and stereo-distribution of triglycerides in human milk from three regions of China

Understanding the components composition characteristics of human milk is conductive for the development of infant formulas. The total fatty acids composition and the stereo-distribution of fatty acids in human milk triglycerides (TGs) from three regions (Zhengzhou, Wuhan and Harbin) of China were analyzed. The total and intrapositional fatty acids composition of human milk TGs showed significant differences among three regions. Zhengzhou, Harbin and Wuhan human milk possessed highest levels of medium-chain fatty acids (MCFA, 6.36 ± 1.46%), short-chain fatty acids (SCFA, 0.10 ± 0.03%) and monounsaturated fatty acids (MUFA, 34.61 ± 0.45%), and polyunsaturated fatty acids (PUFA, 30.34 ± 0.33%), respectively. The preference distribution of fatty acids in human milk TGs was hardly affected by regions, for the relative conservative interpositional levels of each fatty acids in three regions. Not only the specific distribution of sn-2 position, but the esterification of fatty acids in sn-1 and sn-3 positions also had preference. SCFA and MCFA were mainly esterified at sn-3 position, but LCSFA most unlikely distributed at the sn-3 position. The preference esterification of MUFA were sn-1, sn-3 > sn-2, and PUFA were sn-3 > sn-1 > sn-2. Therefore, the optimization of infant formulas not only needs considering total fatty acid composition of TGs but requires thinking over the stereo-distribution of fatty acids.

Comparison of the composition and sensory characteristics of goose fatty liver obtained by overfeeding and spontaneous fattening

ABSTRACTSpontaneous liver steatosis can be experimentally induced in domestic Greylag geese by combining a short photoperiod with a sequence of feed restriction followed by ad libitum corn feeding. This could offer an alternative to the conventional “foie gras” production system based on overfeeding. The present work aimed at comparing the compositional characteristics, sensory profile, and acceptability by a consumer panel of fatty livers obtained by overfeeding and spontaneous fattening. In all, 210 male geese were used: 125 geese were raised over a 31-wk period to produce fatty liver without overfeeding (“alternative livers”) and 85 were raised using conventional methods with overfeeding (“conventional livers”). Mean liver weight was over 1 kg (1,102 g) in the conventional group and 445 g in the alternative group. The characteristics of the livers were studied in 2 subpopulations: 44 conventional livers representative of the experimental population (mean liver weight 1,064 g) and 42 alternative livers weighing more than 400 g (mean 702 g). Compared with the alternative livers, livers from the conventional group showed significantly (P < 0.05) higher dry matter and lipid contents, lighter color (L*), and lower yellowness (b*). The neutral lipids of alternative livers contained significantly less triglycerides and free fatty acids and significantly more cholesterol and cholesterol esters than those from conventional livers. Detailed analysis of the fatty acid composition of triglycerides showed that the proportion of mono- and polyunsaturated fatty acids was significantly higher in the alternative livers. However, covariance analysis suggested that these differences in lipid composition were mainly due to differences in lipid content between both types of livers. The evaluation of cooked livers by a trained expert panel revealed significant differences in the sensory profile between the conventional and alternative livers. The acceptability by a consumer panel was significantly lower in alternative compared to conventional livers. This difference was not related to weight and/or lipid content since livers of similar weight range (800 to 1,000 g) were compared and showed clear-cut differences for hedonic scores.

Characterization of Fatty Acid Composition of Triglycerides in Patients With Hypertriglyceridemia-induced Acute Pancreatitis

Characterization of Fatty Acid Composition of Triglycerides in Patients With Hypertriglyceridemia-induced Acute Pancreatitis

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.

Chemotherapy diminishes lipid storage capacity of adipose tissue in a preclinical model of colon cancer

BackgroundAccelerated loss of adipose tissue in cancer is associated with shorter survival, and reduced quality of life. Evidence is emerging suggesting tumour association with alterations in adipose tissue, but much less is known about drug-related mechanisms contributing to adipose atrophy. Identification of mechanisms by which tumour and cancer treatments, such as chemotherapy, affect adipose tissue are required to develop appropriate therapeutic interventions to prevent fat depletion in cancer. This pre-clinical study aimed to assess alterations in adipose tissue during the clinical course of cancer.MethodsFischer 344 rats bearing the Ward colorectal tumour were euthanized before chemotherapy, after 1- cycle, or 2-cycles of a combination chemotherapy consisting of Irinotecan (CPT-11) combined with 5-fluorouracil (5-FU), which recapitulates first line treatment for human colorectal cancer. Periuterine adipose tissue was isolated. Healthy rats served as a reference group. Histological analysis (hematoxylin and eosin), Real-time PCR (TaqMan) and proteomic analysis (LC-MS/MS) were performed.ResultsLarger adipocytes (3993.7 ± 52.6 μm2) in tumour-bearing animals compared to the reference group (3227.7 ± 36.7 μm2; p < 0.001) was associated with reduced expression of proteins involved in mitochondrial fatty acid oxidation. The presence of a tumour has a significant effect on phospholipid but not triglyceride fatty acid composition. There were greater proportions of saturated fatty acids concurrent with lower monounsaturated fatty acids within the PL fraction of adipocytes in tumour-bearing animals. Chemotherapy treatment decreased the size of adipocytes (2243.9 ± 30.4 μm2; p < 0.001) and led to depletion of n-3 polyunsaturated fatty acids in adipose tissue triglyceride. Evaluation of the proteome profile revealed decreased expression of proteins involved in ATP generation, β-oxidation, and lipogenesis. Overall, adipose tissue may not be able to efficiently oxidize fatty acids to provide energy to maintain energy demanding pathways like lipogenesis inside the tissue.ConclusionsIn conclusion, metabolic adaptations to mitochondrial impairment may contribute to diminished lipid storage capacity of adipose tissue following chemotherapy delivery.

One-Cell Analysis as a Technique for True Single-Cell Analysis of Organelles in Breast Tumor and Adjacent Normal Tissue to Profile Fatty Acid Composition of Triglyceride Species

Breast cancer develops in an adipose rich environment of normal adipocytes that are known to aid in tumor progression through an unknown method of lipid transfer from normal cells to tumor cells. Much research is built around lipid analysis of breast tumor and adjacent normal tissues to identify variations in the lipidome to gain an understanding of the role lipids play in progressing cancer. Ideally, single-cell analysis methods coupled to mass spectrometry that retain spatial information are best suited for this endeavor. However, many single-cell analysis methods are not capable of subcellular analysis of intact lipids while maintaining spatial information. One-Cell analysis is a true single-cell technique with the precision to extract single organelles from intact tissues while not interfering or disrupting adjacent cells. This method is used to extract and analyze single organelles from individual cells using nanomanipulation coupled to nanoelectrospray ionization mass spectrometry. Presented here is a demonstration of the analysis of single lipid bodies from two different sets of breast tumor and normal adjacent tissues to elucidate the fatty acid composition of triglycerides using One-Cell analysis coupled to tandem mass spectrometry. As a result, thirteen fatty acid species unique to the tumor tissues were identified, five in one set of tissues and eight in the other set.

Carnosic Acid Inhibits Lipid Accumulation in 3T3-L1 Adipocytes Through Attenuation of Fatty Acid Desaturation.

Background:Excess body fat accumulation contributes to the development of metabolic disorders that can cause adverse health effects. Carnosic acid (CA), a major bioactive component of rosemary (Rosemarinus officinalis), has been suggested to possess anti-adipogenic properties. The present study was conducted to elucidate the mechanism underlying the anti-adipogenic effects of CA.Methods:3T3-L1 pre-adipocytes were treated with CA (0.1, 1, and 10 μM) from day 0 to day 8 of differentiation. On day 8, biochemical markers of lipid accumulation and the degree of fatty acid desaturation were measured.Results:Oil Red O staining results, triglyceride (TG) accumulation, and glycerol 3-phosphate dehydrogenase activity suggested that CA significantly inhibited lipid accumulation in 3T3-L1 adipocytes. CA significantly decreased mRNA expression of peroxisome proliferator-activated receptor-γ, sterol regulatory element-binding protein 1, and CCAAT/enhancer binding protein-α in a dose-dependent manner. Moreover, it decreased the ratio of both C16:1/C16:0 and C18:1/C18:0, with reduced expression of stearoyl CoA desaturase 1 mRNA and protein.Conclusions:These results suggest that CA efficiently suppressed adipogenesis in 3T3-L1 adipocytes and its action, at least in part, is associated with the downregulation of adipogenesis-related genes and the fatty acid composition of TG accumulated in adipocytes.

In Memoriam

In Memoriam

Fatty acid compositions of triglycerides and free fatty acids in sebum depend on amount of triglycerides, and do not differ in presence or absence of acne vulgaris.

To clarify the influence of the fatty acid composition of sebum in acne vulgaris, we investigated the amounts and fatty acid compositions of triglycerides (TG) and free fatty acids (FFA), and the amounts of cutaneous superficial Propionibacterium acnes in acne patients and healthy subjects. The foreheads of 18 female patients, 10 male patients, 10 healthy females and 10 healthy males were studied in a Japanese population. There were significant differences in the amounts of sebum, TG and cutaneous superficial P.acnes, as well as the fatty acid compositions of TG and FFA between acne patients and healthy subjects in females. Their fatty acid compositions were correlated with the amount of TG with or without acne. It was clarified that the fatty acid compositions of TG and FFA depended on the amount of TG, and there were no differences in the fatty acid composition in the presence and absence of acne.

Quantification of the triglyceride fatty acid composition with 3.0 T MRI.

The aim of this work was to validate a sequential method for quantifying the triglyceride fatty acid composition with 3.0 T MRI. The image acquisition was performed with a 3D spoiled gradient multiple echo sequence. A specific phase correction algorithm was implemented to correct the native phase images for wrap, zero- and first-order phase and rebuild the real part images. Then, using a model of a fat (1)H MR spectrum integrating nine components, the number of double bonds (ndb) and the number of methylene-interrupted double bonds (nmidb) were derived. The chain length (CL) was obtained from these parameters using heuristic approximation. Validations were performed on different vegetable oils whose theoretical fatty acid composition was used as reference and in five human subjects. In vivo measurements were made in the liver and in the subcutaneous and visceral adipose tissues. Linear regressions showed strong correlations between ndb and nmidb quantified with MRI and the theoretical values calculated using oil composition. Mean ndb/nmidb/CL were 1.80 ± 0.25/0.51 ± 0.21/17.43 ± 0.07, 2.72 ± 0.31/0.94 ± 0.16/17.47 ± 0.08 and 2.53 ± 0.21/0.84 ± 0.14/17.43 ± 0.07 in the liver, subcutaneous and visceral adipose tissues respectively. The results suggest that the triglyceride fatty acid composition can be assessed in human fatty liver and adipose tissues with a clinically relevant MRI method at 3.0 T.

High‐fat diet alters serum fatty acid profiles in obesity prone rats: implications for in‐vitro studies

High‐fat diet (HFD) feeding is commonly used in animal models to induce obesity and metabolic diseases. However, the effect of HFD on serum fatty acid profiles remains unclear. Changes in serum fatty acid profiles due to HFD may be a factor in lipotoxicity in various organs. Historically, in vitro studies have utilized individual non‐esterified fatty acids (NEFA) to study lipid exposure, potentially ignoring the importance of fatty acid combinations on cellular lipid metabolism.OBJECTIVETo create a physiological relevant fatty acid mixture to investigate lipid exposure in a cell culture system.METHODSObesity prone rats were fed a HFD (60% en fat) or a control diet (10% en fat) for 2 weeks; portal and systemic blood samples were collected. Triglycerides (TG) and NEFA were extracted and analyzed using gas chromatography.RESULTSBoth systemic and portal serum TG were ~40% lower in HFD. In the control, monounsaturated fatty acids (MUFAs) were the predominant fatty acids in serum TG, whereas polyunsaturated fatty acids (PUFAs) were the dominant fatty acids in the HFD group. Serum NEFA levels were not affected by diet.CONCLUSIONHFD alters serum fatty acid composition of TG from one where MUFAs predominant to PUFAs in rats. A more physiologically relevant fatty acid mixture to mimic HFD conditions for in vitro studies may include increased PUFAs relative to saturated fatty acids and MUFAs. Support: R01DK088940 (JPT)

Partitioning of Organic Chemicals to Storage Lipids: Elucidating the Dependence on Fatty Acid Composition and Temperature

Lipids serve as important compartments in partitioning of neutral organic chemicals into organisms. Storage lipids, made up of triglycerides with various fatty acids, are among the major classes of lipids. Here, we present experimental equilibrium partition data for diverse chemicals in fish oil, linseed oil, and goose fat at 37 °C. These data, in combination with data from the literature for olive oil and milk fat, show that the fatty acid composition of triglycerides has no significant influence on the partition coefficient. This result allows the derivation of a general predictive model for partitioning into storage lipids. We have collected storage lipid/water partition coefficients for 247 compounds to calibrate polyparameter linear free energy relationships (pp-LFERs) for 37 °C, which achieved a model fit with a root mean squared error of 0.20 log units. To extend the applicability of this model toward the aquatic food chain, we also measured fish oil partition data at 7 °C. The resulting enthalpies were used to calibrate an additional pp-LFER for the temperature dependence of storage lipid/water partitioning. This model allows us to estimate partition coefficients at desired temperatures that occur under typical ambient conditions.

Gluteofemoral Adipose Tissue Plays a Major Role in Production of the Lipokine Palmitoleate in Humans

The expansion of lower-body adipose tissue (AT) is paradoxically associated with reduced cardiovascular disease and diabetes risk. We examined whether the beneficial metabolic properties of lower-body AT are related to the production and release of the insulin-sensitizing lipokine palmitoleate (16:1n-7). Using venoarterial difference sampling, we investigated the relative release of 16:1n-7 from lower-body (gluteofemoral) and upper-body (abdominal subcutaneous) AT depots. Paired gluteofemoral and abdominal subcutaneous AT samples were analyzed for triglyceride fatty acid composition and mRNA expression. Finally, the triglyceride fatty acid composition of isolated human preadipocytes was determined. Relative release of 16:1n-7 was markedly higher from gluteofemoral AT compared with abdominal subcutaneous AT. Stearoyl-CoA desaturase 1 (SCD1), the key enzyme involved in endogenous 16:1n-7 production, was more highly expressed in gluteofemoral AT and was associated with greater enrichment of 16:1n-7. Furthermore, isolated human preadipocytes from gluteofemoral AT displayed a higher content of SCD1-derived fatty acids. We demonstrate that human gluteofemoral AT plays a major role in determining systemic concentrations of the lipokine palmitoleate. Moreover, this appears to be an inherent feature of gluteofemoral AT. We propose that the beneficial metabolic properties of lower-body AT may be partly explained by the intrinsically greater production and release of palmitoleate.

On the Bio-Rearrangement into Fully Saturated Fatty Acids-Containing Triglyceride in Aurantiochytrium sp

Abstract A strain of Aurantiochytrium sp. was grown in media with various concentrations of glucose to monitor triglyceride production as a potential source of oil for biodiesel. The fatty acid composition of triglyceride in the strain was unique, because the fatty acids consisted of only 6 molecular species, and the major species were myristic, pentadecanoic, palmitic, heptadecanoic, docosapentaenoic, and docosahexaenoic acids. When cells were cultured in glucose-rich (over 9%) medium for 4 days, the triglyceride yields were 0.5-1.0 g/L. After culture for 4 days, the fatty acid composition of triglyceride was nearly identical in all cells grown in media containing various concentrations of glucose. However, when cells were grown in medium containing 12% glucose for 12 days, unique triglyceride containing only saturated fatty acids accumulated. This bio-rearrangement into fully-saturated fatty acids-containing triglyceride may be utilized for the preparation of biodiesel oil.