Spectral profiles of commercial omega-3 supplements: an exploratory analysis by ATR-FTIR and 1H NMR.

Most of the population is dependent on supplemental products to reach the recommended level of omega-3 polyunsaturated fatty acid (ω-3 PUFA) intake. Thus, knowledge about the quality of ω-3 supplements is important for their safe consumption. In this work, attenuated total reflectance-Fourier transform infrared (ATR-FTIR) and nuclear magnetic resonance (NMR) spectroscopy were applied to assess the quality of fourteen commercial ω-3 supplements. Using ATR-FTIR data, we could identify whether ω-3 PUFA was esterified as either triacylglyceride (71%) or ethyl (29%) esters in ω-3 supplements. The type of esterification is rarely included in the product labels, although the consumer should have the right to choose which form of the supplement to consume. On the other hand, 1H NMR spectra were useful to determine the relative concentration of eicosapentaenoic (EPA) and docosahexaenoic (DHA) acids, and ω-3 PUFA in these commercial samples. Ethyl esters have higher concentrations of unsaturated fatty acids. The NMR results showed a good agreement between the obtained and declared DHA and EPA amounts on the product labels, except for one sample whose high level of ω-3 PUFA indicated it to be a vegetable oil-enriched supplement. Moreover, ω-3 supplements from Schizochytrium sp. microalgae oil revealed higher levels of DHA and ω-3 PUFA, but lower levels of EPA than fish oil. These findings indicate the need for a constant assessment of the quality of commercial products whose ATR-FTIR spectra could be routinely used for the evaluation of PUFA esterification, and NMR analysis could be used to provide advanced quantitative information on commercial ω-3 supplements.

Toward Precision Nutrition: Commercial Infant Formulas and Human Milk Compared for Stereospecific Distribution of Fatty Acids Using Metabolomics.

Precision nutrition and nutrimetabolomics are emerging omics technology applications in public health. In this context, the infant formula (IF) is a manufactured foodstuff that aims to match the composition of human milk (HM), especially the lipid profile. The IF manufacturers have achieved relative success in matching the predominant fatty acid (FAs) profiles, but the stereospecific structures of the triacylglycerides in HM require deeper analyses with system sciences. We employed NMR-based metabolomics to compare the lipid profiles of 12 commercial IF samples and 10 HM samples. Additionally, vegetables, fish, and microalgae oil as raw materials in IFs were also investigated to understand the lipid profile of IFs. We found that IF has significantly less saturated fatty acids (SFA), higher unsaturated FAs, and similar polyunsaturated fatty acid (PUFA) content, compared with HM. However, the main difference was the stereospecific distribution of FAs: HM samples were associated with a high content of SFAs in the sn-2 position (26.03% ± 2.93%) and PUFAs in the sn-1,3 position (15.35% ± 3.94%). The IF had the opposite distribution, with SFAs esterified mainly in the sn-1,3 position (33.07 ± 4.93%) and PUFAs in the sn-2 position (9.57% ± 7.05%). Consequently, the hydrolysis of HM results in SFA mainly as sn-2-monoacylglycerides, which are well absorbed. In contrast, the hydrolysis of the IF provided SFA, mainly as free FAs, which tend to bind calcium and form insoluble calcium soaps in the intestine. Taken together, these observations can inform optimal design of infant formulas with a view to precision nutrition.

Synthesis of structured lipids containing behenic acid from fully hydrogenated Crambe abyssinica oil by enzymatic interesterification.

Low-calorie structured lipids (SLs) rich in behenic and oleic acids were produced by enzymatic (EI) and chemical interesterification (CI) of high oleic sunflower oil and fully hydrogenated Crambe abyssinica oil in proportions of 60:40, 50:50, 40:60 and 30:70 (w/w), respectively. The immobilized lipase from Thermomyces lanuginosus (Lipozyme TL IM) was used for 3 h at 70 °C at a dosage of 7% (w/w) free of organic solvents. The original blend (BE) and the reaction products were evaluated for their fatty acid (FA) and triacylglycerols (TAG) compositions, solid fat contents, thermal analysis, regiospecific distribution of the FA, microstructure and polymorphism. The tendency was towards a reduction in the C52, C54, C60, C62 and C64 TAG contents and an increase in the C56, C58 e C66 TAG contents, therefore the solid fat content was reduced. There was lower acyl migration at the sn-2 position of the TAGs in EI as compared to CI in all the blends ratios. Needle-like crystals were predominant in the IE while large symmetrical spherulites were observed in the BE. Reduction in the mean crystal diameter was observed in all the blends, in addition to modifications of the crystal morphology. X-ray diffraction analysis showed a predominance of the ß' form crystals in both the IE and CI. The SLs were produced for application in the food industry as bakery/confectionery fats in the proportions of 60:40/50:50 and as additive in the crystallization of lipids in the proportions of 40:60/30:70.

"Omics" Prospective Monitoring of Bariatric Surgery: Roux-En-Y Gastric Bypass Outcomes Using Mixed-Meal Tolerance Test and Time-Resolved (1)H NMR-Based Metabolomics.

Roux-en-Y gastric bypass (RYGB) surgery goes beyond weight loss to induce early beneficial hormonal changes that favor glycemic control. In this prospective study, ten obese subjects diagnosed with type 2 diabetes underwent bariatric surgery. Mixed-meal tolerance test was performed before and 12 months after RYGB, and the outcomes were investigated by a time-resolved hydrogen nuclear magnetic resonance ((1)H NMR)-based metabolomics. To the best of our knowledge, no previous omics-driven study has used time-resolved (1)H NMR-based metabolomics to investigate bariatric surgery outcomes. Our results presented here show a significant decrease in glucose levels after bariatric surgery (from 159.80 ± 61.43 to 100.00 ± 22.94 mg/dL), demonstrating type 2 diabetes remission (p < 0.05). The metabolic profile indicated lower levels of lactate, alanine, and branched chain amino acids for the operated subject at fasting state after the surgery. However, soon after food ingestion, the levels of these metabolites increased faster in operated than in nonoperated subjects. The lipoprotein profile achieved before and after RYGB at fasting was also significantly different, but converging 180 min after food ingestion. For example, the very low-density lipoprotein, low-density lipoprotein, N-acetyl-glycoproteins, and unsaturated lipid levels decreased after RYGB, while phosphatidylcholine and high-density lipoprotein increased. This study provides important insights on RYGB surgery and attendant type 2 diabetes outcomes using an "omics" systems science approach. Further research on metabolomic correlates of RYGB surgery in larger study samples is called for.

Comparison of the regiospecific distribution from triacylglycerols after chemical and enzymatic interesterification of high oleic sunflower oil and fully hydrogenated high oleic sunflower oil blend by carbon-13 nuclear magnetic resonance.

The nutritional and organoleptic attributes of oils can proceed via interesterification of oils blends catalyzed by enzymes or chemicals. Enzymatic interesterification processes are preferred due the regiospecific outcome. Traditionally, monitoring of distribution of fatty acids (FA) in glycerol backbone is performed by enzymatic and chromatographic methods that are time-consuming, involving a series of chemical manipulations employing large volumes of organic solvents. Alternatively, carbon-13 nuclear magnetic resonance ((13)C NMR) is a fast and reliable technique that could be applied to determine the saturated and unsaturated FA distribution of the triacylglycerols (TAGs) present in high oleic sunflower oil (SO) and fully hydrogenated high oleic sunflower oil (HSO) blends and their interesterification products. The enzymatic interesterification was conducted employing the immobilized lipase from Thermomyces lanuginosus (Lipozyme TL IM), the results show that the process was not completely regiospecific at sn-1,3 positions, due to the spontaneous acyl migration from position sn-2 to sn-1,3.

Blood Metabolome Changes Before and After Bariatric Surgery: A (1)H NMR-Based Clinical Investigation.

Excessive body fat and obesity have adverse health effects and result in significant morbidity such as type 2 diabetes mellitus. The health burden of obesity can be reduced with the Roux-en-Y gastric bypass (RYGB) weight-loss bariatric surgery. Little is known on the molecular changes that occur at the metabolome level before and after bariatric surgery, with a view to clinical biomarker development. Hence, we employed a metabolomics approach in 10 obese diabetic patients who underwent bariatric surgery. Metabolomics data were obtained by T2- and diffusion-edited hydrogen nuclear magnetic resonance ((1)H NMR) spectra to monitor the metabolic and lipoprotein profiles, and gas chromatography-mass spectrometry (CG-MS) to access the fatty acid profile before and 12 months after RYGB. Using hierarchical partial least squares discriminant analysis, we found that RYGB induces several key metabolic alterations associated with glucose homeostasis, as well as fatty acid and amino acid metabolism. The levels of lactate (Krebs' intermediate cycle) decreased after RYGB. The leucine, isoleucine, valine, lactate, and glucose levels were higher in the samples before RYGB (p<0.05). Additionally, the levels of very low-density lipoprotein, unsaturated lipids, and N-acetyl-glycoprotein were higher before RYGB. By contrast, levels of the high-density lipoprotein and phosphatidylcholine were higher after bariatric surgery. These results collectively offer important holistic integrative biology data to develop future clinically relevant metabolomics biomarkers related to bariatric surgery in connection with obesity.

Lichen metabolites modulate hydrogen peroxide and nitric oxide in mouse macrophages.

The activities of perlatolic acid (1), atranorin (2), and lecanoric acid (3) and their derivatives, such as orsellinates and beta-methyl orsellinates obtained by alcoholysis, were assessed for stimulation of the release of hydrogen peroxide and nitric oxide in cultures of peritoneal macrophage cells from mice. The hydrogen peroxide production was estimated by oxidation of phenol red, while the Griess reagent was used to determine the nitric oxide production. 1 and 4-methoxy-ethyl orsellinate (XVII) were the compounds that induced the greatest release of H2O2, whereas n-pentyl orsellinate (IV), iso-propyl orsellinate (V), sec-butyl orsellinate (VI), and XVII induced a small release of NO. These results indicate that lichen products and their derivatives have potential immune-modulating activities.