Lipidomic Approaches to Study HDL Metabolism in Patients with Central Obesity Diagnosed with Metabolic Syndrome

The metabolic syndrome (MetS) is a cluster of cardiovascular risk factors characterised by central obesity, atherogenic dyslipidaemia, and changes in the circulating lipidome; the underlying mechanisms that lead to this lipid remodelling have only been partially elucidated. This study used an integrated “omics” approach (untargeted whole serum lipidomics, targeted proteomics, and lipoprotein lipidomics) to study lipoprotein remodelling and HDL composition in subjects with central obesity diagnosed with MetS (vs. controls). Compared with healthy subjects, MetS patients showed higher free fatty acids, diglycerides, phosphatidylcholines, and triglycerides, particularly those enriched in products of de novo lipogenesis. On the other hand, the “lysophosphatidylcholines to phosphatidylcholines” and “cholesteryl ester to free cholesterol” ratios were reduced, pointing to a lower activity of lecithin cholesterol acyltransferase (LCAT) in MetS; LCAT activity (directly measured and predicted by lipidomic ratios) was positively correlated with high-density lipoprotein cholesterol (HDL-C) and negatively correlated with body mass index (BMI) and insulin resistance. Moreover, many phosphatidylcholines and sphingomyelins were significantly lower in the HDL of MetS patients and strongly correlated with BMI and clinical metabolic parameters. These results suggest that MetS is associated with an impairment of phospholipid metabolism in HDL, partially led by LCAT, and associated with obesity and underlying insulin resistance. This study proposes a candidate strategy to use integrated “omics” approaches to gain mechanistic insights into lipoprotein remodelling, thus deepening the knowledge regarding the molecular basis of the association between MetS and atherosclerosis.     

Spatiotemporal aspects of real-time PM(2.5): low- and middle-income neighborhoods in Bangalore, India

We measured outdoor fine particulate matter (PM(2.5)) concentrations in a low- and a nearby middle-income neighborhood in Bangalore, India. Each neighborhood included sampling locations near and not near a major road. One-minute average concentrations were recorded for 168 days during September 2008 to May 2009 using a gravimetric-corrected nephelometer. We also measured wind speed and direction, and PM(2.5) concentration as a function of distance from road. Average concentrations are 21-46% higher in the low- than in the middle-income neighborhood, and exhibit differing spatiotemporal patterns. For example, in the middle-income neighborhood, median concentrations are higher near-road than not near-road (56 versus 50 μg m(-3)); in the low-income neighborhood, the reverse holds (68 μg m(-3) near-road, 74 μg m(-3) not near-road), likely because of within-neighborhood residential emissions (e.g., cooking; trash combustion). A moving-average subtraction method used to infer local- versus urban-scale emissions confirms that local emissions are greater in the low-income neighborhood than in the middle-income neighborhood; however, relative contributions from local sources vary by time-of-day. Real-time relative humidity correction factors are important for accurately interpreting real-time nephelometer data.     

Structured biopolymer-based delivery systems for encapsulation,protection, and release of lipophilic compounds

Food-grade biopolymers, such as proteins and polysaccharides, can be used to create a diverse range of delivery systems suitable for encapsulating, protecting, and delivering lipophilic functional components, such as ω-3 rich oils, conjugated linoleic acid (CLA), oil-soluble vitamins, flavors, colors, and nutraceuticals. This article provides an overview of a number of different approaches that can be used to create structured delivery systems based on biopolymers, including molecular complexation, coacervation, thermodynamic incompatibility, moulding, and extrusion methods. These delivery systems can be produced from food-grade ingredients using simple processing operations (e.g., mixing, homogenizing, and thermal processing). The structure, production, performance, and potential applications of each type of structured delivery system are discussed.     

Feeding barley grain steeped in lactic acid modulates rumen fermentation patterns and increases milk fat content in dairy cows

The objectives of the present in vivo and in situ trials were to evaluate whether feeding barley grain steeped in lactic acid (LA) would affect rumen fermentation patterns, in situ dry matter (DM) degradation kinetics, and milk production and composition in lactating dairy cows. The in vivo trial involved 8 rumen-fistulated Holstein cows fed once daily a total mixed ration containing rolled barley grain (27% in DM) steeped for 48 h in an equal quantity of tap water (CTR) or in 0.5% LA (TRT) in a 2 × 2 crossover design. The in situ trials consisted of incubation of untreated rolled barley grain in cows fed CTR or TRT diets and of incubation of 3 different substrates including CTR or barley grain steeped in 0.5% or 1.0% LA (TRT1 and TRT2, respectively) up to 72 h in the rumen. Results of the in vivo trial indicated that cows fed the TRT diet had greater rumen pH during most intensive fermentation phases at 10 and 12 h post-feeding. The latter effect was associated with a shorter duration in which rumen pH was below 5.8 for cows fed the TRT diet (2.4 h) compared with CTR diet (3.9 h). Furthermore, cows fed the TRT diet had lower concentrations of volatile fatty acids at 2 and 4 h post-feeding. In addition, concentrations of preprandial volatile fatty acids were lower in the rumen fluid of cows fed the TRT diet. Results also showed that molar proportion of acetate was lower, whereas propionate tended to increase by feeding cows the TRT diet. Cows fed the TRT diet demonstrated greater rumen in situ lag time of substrate DM degradation and a tendency to lower the fractional degradation rate. Other in situ results indicated a quadratic effect of LA on the effective rumen degradability of substrates whereby the latter variable was decreased from CTR to TRT1 but increased for TRT2 substrate. Although the diet did not affect actual milk yield, fat-corrected milk, percentages of milk protein, and lactose and concentration of milk urea nitrogen, cows fed the TRT diet increased milk fat content and tended to increase fat:protein ratio in the milk. In conclusion, results demonstrated that treatment of barley grain with LA lowered the risk of subacute rumen acidosis and maintained high milk fat content in late-lactating Holstein cows fed diets based on barley grain.     

Influence of chitosan on stability and lipase digestibility of lecithin-stabilized tuna oil-in-water emulsions

The influence of chitosan concentration (0–0.3 wt%) and molecular weight (120, 250 and 342.5 kDa) on the physical stability and lipase digestibility of lecithin-stabilized tuna oil-in-water emulsions was studied. The ζ-potential, droplet size, creaming stability, free fatty acids and glucosamine released was measured for the emulsions when they were subjected to an in vitro digestion model. The ζ-potential of the oil droplets in lecithin-chitosan stabilized emulsions changed from positive (≈+53 mV) to negative and the emulsions were unstable to droplet aggregation for all chitosan concentrations and molecular weights used after being subjected to the digestion model. The amount of free fatty acid and glucosamine released per unit amount of emulsion was higher when pancreatic lipase was included in the digestion model. These results suggest that lecithin-chitosan coated droplets can be degraded by lipase under simulated gastrointestinal conditions. Consequently, chitosan coated lipid droplets may serve as useful carriers for the delivery of bioactive lipophilic nutraceuticals.     

Impact of iron encapsulation within the interior aqueous phase of water-in-oil-in-water emulsions on lipid oxidation

Iron (Fe³⁺) was encapsulated within the internal aqueous phase of water-in-oil-in-water (W/O/W) emulsions, and then the impact of this iron on the oxidative stability of fish oil droplets was examined. There was no significant change in lipid droplet diameter in the W/O/W emulsions during 7 days storage, suggesting that the emulsions were stable to lipid droplet flocculation and coalescence, and internal water diffusion/expulsion. The initial iron encapsulation (4 mg/100 g emulsion) within the internal aqueous phase of the water-in-oil (W/O) emulsions was high (>99.75%), although, a small amount leaked out over 7 days storage (≈10 μg/100 g emulsion). When W/O/W emulsions were mixed with fish oil droplets the thiobarbituric acid-reactive substances (TBARS) formed decreased (compared to fish oil droplets alone) by an amount that depended on iron concentration and location, i.e., no added iron < iron in external aqueous phase < iron in internal aqueous phase. These differences were attributed to the impact of W/O droplets on the concentration and location of iron and lipid oxidation reaction products within the system.     

The integration of process and cost modeling—A powerful tool for business planning

Recent developments in modeling can eliminate much experimental laboratory work and can provide quick answers in a more cost-effective manner. This article presents a brief outline of technical cost modeling, a combination of physical modeling and cost modeling, which may be used to the mutual benefit of both the managerial decision makers and the R&D community within the materials processing field.     

Investigation of ammonium polyphosphate dilution with ground eggshells and lignin through the study of natural fibre composite flammability

The interactions of Calcium carbonate (e.g., eggshell powder) and Lignin with ammonium polyphosphate (APP) when used as fire retardants were investigated. Three mixing ratios - 1:3, 1:1, and 3:1, were used with natural fibre reinforced composites containing a hemp mat and an epoxy matrix manufactured using a light resin transfer moulding (L-RTM) process. The thermal decomposition of the retardant mixtures and composites was investigated using thermogravimetric analysis (TGA). The findings showed that even though the decomposition reactions of APP with eggshell powder and lignin mixtures interacted and overlapped, the same interactions could not be seen in the composites. In the composite form while the residue was affected by the retardant, the decomposition reactions were driven primarily by the hemp and epoxy. Flammability of the composites was studied by testing to 20, 35, 50, and 75 kW/m² with a cone calorimeter, and determining the critical heat flux. While the samples with eggshell powder had higher ignition times, the critical heat flux for ignition was 13 kW/m² for all sample groups except for a ratio of 1:3 APP to eggshell powder, which was 14 kW/m². The lowest burning rates (mass loss and heat release) occurred in composites containing only APP, however, the addition of eggshell powder or lignin at even a ratio of 3:1 APP to either provided a notable reduction.