Soybean Oil Emulsion Research Articles

Kinetically stable propofol emulsions with reduced free drug concentration for intravenous delivery

PurposeIntravenous injections of propofol emulsions are accompanied by pain likely due to the interaction of the dissolved drug with endothelial cells of the vasculature. It is commonly hypothesized that reducing the aqueous phase concentration of propofol could reduce pain. MethodsTo minimize the propofol concentration in the aqueous phase, we developed stable oil-in-water emulsions with excipient oil mixtures that have an increased partition coefficient for propofol. We then explored the emulsion stability by measuring size distributions after extended durations of shelf storage and also after freeze–thaw cycling. The effects of oil type, surfactant and salt concentration on emulsion stability were also explored. ResultsSmall chain oils like ethyl butyrate exhibit high drug partitioning but poor stability, while larger molecules such as soybean oil exhibit lower partitioning but excellent emulsion stability. Emulsions with mixtures of soybean oil and ethyl butyrate are stable for longer than a year, resistant to freeze–thaw cycling, and reduce aqueous drug concentrations of propofol twofold compared to pure soybean oil emulsions. ConclusionsOil-in-water emulsions of propofol formulated with mixtures of ethyl butyrate and soybean oil are kinetically stable and significantly reduce the aqueous phase drug concentration making them promising candidates for future propofol therapies.

Benefits of Alternative Oil Sources for IV Lipid Emulsions

Soybean oil lipid emulsions for parenteral nutrition have been used since the 1960s. Alternative oils were developed to reduce the phytosterols and linoleic acid in soybean oil emulsions, which promote the stress response, suppress immune function, and impair liver function. Clinical studies have demonstrated that olive and other oil sources are safe and effective in adult and pediatric patient populations.

Control of powdery mildew on glasshousegrown roses and tomatoes in the Netherlands using anhydrous milk fat and soybean oil emulsions

Powdery mildew (PM) is a very serious disease affecting glasshousegrown roses and tomatoes in the Netherlands Control is limited because of resistance to existing fungicides Anhydrous milk fat (AMF) and soybean oil (SBO) emulsions were evaluated for control of PM in roses and tomatoes Both AMF (14 g/litre) and SBO (14 g/litre) provided powdery mildew control on rose leaves and blooms that was significantly better (P

Flavor Preferences in Animals: Role of Mouth and Gut Nutrient Sensors

Flavor Preferences in Animals: Role of Mouth and Gut Nutrient Sensors

Intravenous lipids in preterm infants: impact on laboratory and clinical outcomes and long-term consequences.

Postnatal growth failure is still one of the most commonly observed morbidities in preterm infants. Intolerance of enteral nutrition is a common problem in these infants and in neonates with surgical conditions. Therefore, adequate parenteral nutrition is crucial to support organ development, including that of the brain. Short-term studies on the early introduction of parenteral lipids have demonstrated that early lipid administration seems safe and well tolerated and prevents essential fatty acid deficiency. Further well-designed and adequately powered studies are necessary to determine the optimal dose of lipid infusion and the long-term effects on morbidity, growth, and neurodevelopment. Administration of a pure soybean oil emulsion might result in excess formation of proinflammatory eicosanoids and peroxidation, and their use reduces the availability of the long-chain polyunsaturated fatty acids necessary for central nervous system development and immune function. Alternatives to the use of pure soybean oils include emulsions with partial replacement of soybean oil with medium-chain triglycerides, olive oil, and/or fish oil. These newer lipid emulsions offer many theoretical advantages. Future large-scale randomized controlled trials in premature infants should demonstrate whether these newer lipid emulsions are truly safe and result in improved short- and long-term outcomes. It seems safe to start lipid emulsions from birth onward at a rate of 2 g lipids/kg/day (based on short-term results only). Mixed lipid emulsions, including those containing fish oil, seem to reduce nosocomial infections in preterm infants and might reduce bile acid accumulation. Liver damage may be reduced by decreasing or removing lipids from parenteral nutrition or may be reduced by using fish oil-containing lipid emulsions containing high levels of vitamin E.

Antioxidant activities and interactions of α‐ and γ‐tocopherols within canola and soybean emulsions

During the 1940s, basic theories addressing the chemistry of lipid oxidation were developed, namely the free radical theory of hydroperoxide formation and decomposition and its inhibition by antioxidants. Tocopherols, especially the α‐ and γ‐homologs, are the primary antioxidants in vegetable oils. α‐Tocopherol having a fully substituted phenolic ring has a stronger power than γ‐tocopherol in scavenging free radicals in solutions but this is not consistently the case in foods, including vegetable oils and their emulsions. Paradoxical results on the superiority of these two closely related antioxidants over each other are often found. The article by Moser et al. in this issue of the European Journal of Lipid Science and Technology presents a comprehensive study comparing the antioxidant activities of α‐ and γ‐tocopherols and their interactions in 10% canola and soybean oil‐in‐water emulsions incubated at 50°C. The oxidation of stripped oils, supplemented with known concentrations of α‐ and/or γ‐tocopherols, was followed by measuring the evolution of hydroperoxides and their decomposition product hexanal. The results were affected by the oil matrix. In canola oil emulsions, γ‐tocopherol was a stronger antioxidant than α‐tocopherol (at 200 or 600 µg/g oil) and their interaction was additive even at 600 + 600 µg/g oil level. In soybean oil emulsions, α‐tocopherol was the stronger antioxidant at concentrations up to 250 µg/g oil while γ‐tocopherol was the stronger antioxidant at the higher concentrations and the interaction between the two tocopherols was synergistic at the low concentrations (200 + 200 µg/g oil) but was either additive or antagonistic at higher concentrations. In both oils, α‐tocopherol lost antioxidant effectiveness at around 400 µg/g oil.

Low-Dose Intravenous Soybean Oil Emulsion for Prevention of Cholestasis in Preterm Neonates.

Premature infants depend on intravenous fat emulsions to supply essential fatty acids and calories. The dose of soybean-based intravenous fat emulsions (S-IFE) has been associated with parenteral nutrition (PN)-associated liver disease. This study's purpose was to determine if low-dose S-IFE is a safe and effective preventive strategy for cholestasis in preterm neonates. This is a multicenter randomized controlled trial in infants with a gestational age (GA) ≤29 weeks. Patients <48 hours of life were randomized to receive a low (1 g/kg/d) or control dose (approximately 3 g/kg/d) of S-IFE. The primary outcome was cholestasis, defined as a direct bilirubin ≥15% of the total bilirubin at 28 days of life (DOL) or full enteral feeds, whichever was later, after 14 days of PN. Secondary outcomes included growth, length of hospital stay, death, and major neonatal morbidities. In total, 136 neonates (67 and 69 in the low and control groups, respectively) were enrolled. Baseline characteristics were similar for the 2 groups. When the low group was compared with the control group, there was no difference in the primary outcome (69% vs 63%; 95% confidence interval, -0.1 to 0.22; P = .45). While the low group received less S-IFE and total calories over time compared with the control group (P < .001 and P = .03, respectively), weight, length, and head circumference at 28 DOL, discharge, and over time were not different (P > .2 for all). Compared with the control dose, low-dose S-IFE was not associated with a reduction in cholestasis or growth.

Growth and Fatty Acid Profiles of VLBW Infants Receiving a Multicomponent Lipid Emulsion From Birth

Very-low-birth-weight (VLBW) infants are dependent on parenteral nutrition after birth. A parenteral lipid emulsion with a multicomponent composition may improve growth and neurodevelopment and may prevent liver injury, which is often observed in association with long-term parenteral nutrition with pure soybean oil. Our aim was to evaluate the safety and efficacy of a multicomponent lipid emulsion containing 30% soybean oil, 30% medium-chain triacylglycerol, 25% olive oil, and 15% fish oil compared with a conventional pure soybean oil emulsion in VLBW infants. We conducted a double-blind randomized controlled trial in VLBW infants randomized to parenteral nutrition with the multicomponent (study group) or pure soybean oil emulsion (control group) from birth at a dose of 2 to 3 g · kg(-1) · day(-1) until the infants were receiving full enteral nutrition. We assessed efficacy by growth rates and measuring plasma fatty acid profiles (representative subset). Safety was evaluated by assessing hematologic and biochemical parameters, potentially harmful phytosterol concentrations (same subset), and clinical neonatal outcome parameters. Ninety-six infants were included (subsets n = 21). The multicomponent emulsion was associated with higher weight and head circumference z scores during admission. Plasma eicosapentaenoic acid and docosahexaenoic acid concentrations were higher in the study group. The hematological, biochemical, and neonatal outcomes were not different between groups, whereas the plasma concentrations of phytosterols were higher in the control group. The multicomponent lipid emulsion was well tolerated and associated with improved growth and higher plasma fatty acid profiles in VLBW infants in comparison with the pure soybean oil emulsion.

Antioxidant activities and interactions of α‐ and γ‐tocopherols within canola and soybean oil emulsions

The effect of differing concentrations and ratios of α‐ and γ‐TOH on oxidative stability over time was determined by measuring the development of hydroperoxides and volatile secondary oxidation products (hexanal) within a series of oil‐in‐water (o/w) emulsion systems produced from both canola oil (CO) and soybean oil (SBO). Overall rates for hydroperoxide and hexanal formation were lower in CO than in SBO. In CO emulsions, γ‐TOH was a stronger antioxidant than α‐TOH, and their interaction in mixtures was additive. In SBO emulsions, α‐TOH was a better antioxidant at lower concentrations, while γ‐TOH was better at higher concentrations. The interaction between α‐ and γ‐TOH was synergistic at low concentrations, but either additive or antagonistic at higher concentrations, depending on the concentration and ratio of the two TOHs. In both CO and SBO emulsions, α‐TOH became less effective at higher concentrations, while γ‐TOH activity increased with increasing concentrations.Practical applications: Tocopherols are widely used natural antioxidants in human and pet foods, cosmetics, and supplements. This work provides information about the different antioxidant activities of α‐ and γ‐TOH and their interactions in o/w emulsions made with two of the most widely produced and utilized vegetable oils. This information can be applied to determine the best levels and ratios of tocopherols to protect emulsions depending on the type of oil that is used.

Effect of pre-emulsification of plant lipid treated by pulsed ultrasound on the functional properties of chicken breast myofibrillar protein composite gel

To explore novel methods for reducing the saturated fatty acid content in meat products, pre-emulsified plant lipids prepared using pulsed ultrasound were used to replace animal fat. Chicken breast myofibrillar protein (MP)–soybean oil emulsion composite gels (SMG) were prepared from 3% chicken breast MP with 27.5% soybean oil incorporated as pre-emulsification with 0.5% sodium caseinate (0.6M NaCl and 50mM phosphate solution, pH6.25). One-factor-at-a-time experiments were carried out to investigate the effect of different ultrasound treatment times on the texture [rheology and texture profile analysis (TPA)], water- and fat-binding (WFB) capacities, and microstructural properties of SMG. Rheological tests showed that ultrasound-treated samples formed a more viscoelastic gel than the control. WFB and textural properties were also significantly improved by pulsed ultrasound (P<0.05). The ultrasound-treated gels exhibited homogeneous fine network microstructures when the ultrasound time was 6min. G′72°C and G″72°C were highly correlated (P<0.01) with WFB and TPA (hardness, springiness, chewiness, cohesiveness, and resilience). These findings show that ultrasound treatment has potential in improving the fatty acid composition of emulsion-type meat products with good functional properties and high yields.

Synthesis of alkyne-functionalized amphiphilic polysiloxane polymers and formation of nanoemulsions conjugated with bioactive molecules by click reactions

Nanoemulsions are useful as drug carriers. Conjugating targeting molecules to nanoemulsions would expand their application to the cell-specific delivery of drugs. Click reactions, such as the Cu (I)-catalyzed azide-alkyne 1,3-dipolar cycloaddition (CuAAC) reaction, are a convenient tool for such functionalization as the conjugation of label or targeting molecules. In this study, we sought to synthesize siloxane-based amphiphilic polymers containing alkyne moieties to form nanoemulsions capable of conjugating azide-functionalized labels by the CuAAC reaction. The siloxane-based homopolymer (P1) and copolymer with polydimethylsiloxane (P2) containing chloropropyl groups were reacted with an imidazole derivative that had an ethynyl group at the 1-position to generate PIm1 and PIm2, respectively. PIm1 and PIm2 exhibited good solubility in polar solvents such as methanol, dimethylformamide, dimethyl sulfoxide and H2O. Further, PIm2 exhibited solubility in chloroform and dichloromethane. Azide-functionalized fluorescent dyes and green fluorescent proteins were conjugated with PIm1 and PIm2 by the CuAAC reaction. The labeled polymer emulsified soybean oil in water to form emulsions. The average emulsion size was 150 nm. The fluorescent labels on the emulsions were successfully observed with a fluorescent microscope. Conjugation of PIm1 and PIm2 with targeting molecules by the click reaction would be useful for cell-specific drug delivery.

GPR40 and GPR120 fatty acid sensors are critical for postoral but not oral mediation of fat preferences in the mouse

In addition to orosensory signals, postoral actions of fat stimulate appetite and condition flavor preferences, but the gut sensors mediating these responses are unknown. Here, we investigated the role of the fatty acid sensors GPR40 and GPR120 in postoral and oral preferences for a soybean oil emulsion (Intralipid). Mice were trained to drink a flavored solution (CS+) paired with intragastric (IG) oil infusions and another flavored solution (CS-) paired with water infusions. Knockout (KO) mice missing GPR40 or GPR120 sensors increased their CS+ intake in one-bottle tests (1 h/day) but less so than wild-type (WT) mice. The KO mice also preferred the CS+ to CS- in a two-bottle test, but the preference was attenuated in GPR40 KO mice. Double-knockout (DoKO) mice missing both GPR40 and GPR120 displayed attenuated stimulation of CS+ intake and only a marginal CS+ preference. The DoKO mice developed a more substantial CS+ preference when tested 24 h/day, although weaker than that of WT mice. The DoKO mice also consumed less of the CS+ paired with IG Intralipid, as well as less Intralipid in oral tests. However, DoKO mice, like GPR40 KO and GPR120 KO mice did not differ from WT mice in their preference for Intralipid over water at 0.001%-20% concentrations. In contrast to prior results obtained with mice missing the CD36 fatty acid sensor, these findings indicate that, together, GPR40 and GPR120 play a critical role in the postoral stimulation of appetite by fat but are not essential for oral fat preferences.

Constant flux crossflow filtration evaluation of surface-modified fouling-resistant membranes

The surfaces of polysulfone ultrafiltration membranes were modified with polydopamine and polydopamine-g-poly(ethylene glycol) hydrophilic coatings. Unmodified and modified membranes were challenged with a soybean oil emulsion feed at six different permeate fluxes in constant flux crossflow filtration fouling studies. The threshold flux was determined for each membrane. Above the threshold flux, modified membranes generally exhibited lower transmembrane pressures than unmodified membranes. However, below the threshold flux, modified membranes had higher transmembrane pressures than unmodified membranes, likely due to a decrease in permeance resulting from the surface modification. To account for this difference in permeance, polydopamine-g-poly(ethylene glycol) modified membranes were compared to membranes with a thicker polydopamine coating and to an unmodified membrane with a smaller pore size than that used for the surface modified membranes; in this way, all three membranes had similar pure water permeances. In this case, the unmodified membrane exhibited a much higher transmembrane pressure during fouling than the modified membranes, so when membranes of the same permeance are compared, the surface modifications improved fouling resistance. Therefore, a potential strategy to achieve fouling resistance in a membrane of a desired flux and rejection is to modify the surface of a more permeable (and perhaps lower rejection) membrane, thereby making the resulting modified membrane fouling-resistant but leaving it with the desired flux and rejection characteristics.

Fish‐Oil Fat Emulsion Supplementation Reduces the Risk of Retinopathy in Very Low Birth Weight Infants

Preliminary studies suggest that fish-oil lipid emulsion given parenterally to very preterm infants reduces the severity of retinopathy (ROP) and cholestasis. Infants weighing <1250 g at birth were randomly allocated to 2 groups: an experimental group of 60 infants that received an intravenous (IV) soybean, olive oil, and fish oil emulsion, and a control group of 70 infants that was given a parenteral soybean and olive oil emulsion. Plasma and erythrocyte concentrations of docosahexaenoic acid (DHA) were determined using a high-performance liquid chromatography-mass spectrometry analysis. Nine infants in the fish oil group required laser therapy for ROP compared with 22 infants in the standard intralipid group (risk ratio [RR], 0.48; 95% confidence interval [CI], 0.24-0.96). Three infants in the fish oil group developed cholestasis compared with 20 infants in the standard intralipid group (RR, 0.18; 95% CI, 0.055-0.56). The mean plasma DHA concentrations in treated infants were 2.9-fold higher in the fish oil group than in control infants on the 7th and 14th days of life. The mean DHA content in erythrocytes of treated infants was 4.5-fold and 2.7-fold higher compared with controls at 7 and 14 days of age. Premature infants receiving an IV fat emulsion containing fish oil had less ROP requiring laser treatment and less cholestasis than those receiving a standard lipid emulsion. These infants also had higher plasma and erythrocyte DHA levels at 7 and 14 days, suggesting potential long-term neurodevelopmental benefits.

A Model of Chronic Nutrient Infusion in the Rat

Chronic exposure to excessive levels of nutrients is postulated to affect the function of several organs and tissues and to contribute to the development of the many complications associated with obesity and the metabolic syndrome, including type 2 diabetes. To study the mechanisms by which excessive levels of glucose and fatty acids affect the pancreatic beta-cell and the secretion of insulin, we have established a chronic nutrient infusion model in the rat. The procedure consists of catheterizing the right jugular vein and left carotid artery under general anesthesia; allowing a 7-day recuperation period; connecting the catheters to the pumps using a swivel and counterweight system that enables the animal to move freely in the cage; and infusing glucose and/or Intralipid (a soybean oil emulsion which generates a mixture of approximately 80% unsaturated/20% saturated fatty acids when infused with heparin) for 72 hr. This model offers several advantages, including the possibility to finely modulate the target levels of circulating glucose and fatty acids; the option to co-infuse pharmacological compounds; and the relatively short time frame as opposed to dietary models. It can be used to examine the mechanisms of nutrient-induced dysfunction in a variety of organs and to test the effectiveness of drugs in this context.

Effects on Varying Intravenous Lipid Emulsions on the Small Bowel Epithelium in a Mouse Model of Parenteral Nutrition

Injectable fat emulsions (FEs) are a clinically dependable source of essential fatty acids (FA). ω-6 FA is associated with an inflammatory response. Medium-chain triglycerides (MCT, ω-3 FA), fish oil, and olive oil are reported to decrease the inflammatory response. However, the effect of these lipids on the gastrointestinal tract has not been well studied. To address this, we used a mouse model of parenteral nutrition (PN) and hypothesized that a decrease in intestinal inflammation would be seen when either fish oil and MCT or olive oil were added. Three FEs were studied in adult C57BL/6 mice via intravenous cannulation: standard soybean-based FE (SBFE), 80% olive oil -supplemented FE (OOFE), or a combination of a soybean oil, MCT, olive oil, and fish oil emulsion (SMOF). PN was given for 7 days, small bowel mucosa-derived cytokines, animal survival rate, epithelial cell (EC) proliferation and apoptosis rates, intestinal barrier function and mucosal FA composition were analyzed. Compared to the SBFE and SMOF groups, the best survival, highest EC proliferation and lowest EC apoptosis rates were observed in the OOFE group; and associated with the lowest levels of tumor necrosis factor-α, interleukin-6, and interleukin-1β expression. Jejunal FA content showed higher levels of eicosapentaenoic and docosapentaenoic acid in the SMOF group and the highest arachidonic acid in the OOFE group. The study showed that PN containing OOFE had beneficial effects to small bowel health and animal survival. Further investigation may help to enhance bowel integrity in patients restricted to PN.

How does oil type determine emulsion characteristics in concentrated Na-caseinate emulsions?

Macroscopic properties and ensemble average diffusion of concentrated (dispersed phase 50–60wt%) Na-caseinate-stabilised emulsions for three different oils (soybean oil, palm olein and tetradecane) were explored. On a volume fraction basis, pulsed gradient stimulated echo (PGSTE)-NMR data show that droplet dynamics for all three systems are similar within a region of the emulsion morphology diagram. The exact limits of the emulsion space depend however on which oil is considered. The reduced solubility of tetradecane in water, and Na-caseinate in tetradecane, result in the stabilisation of flocs during formulation. Floc formation is not observed when soybean oil or palm olein is used under identical emulsion formulation conditions. Linear rheology experiments provide indirect evidence that the local structure and the properties of the thin film interfacial domain of tetradecane emulsions vary from those of soybean oil and palm olein emulsions. Collectively these data indicate that protein/oil interactions within a system dominate over specific oil droplet structure and size distribution, which are similar in the three systems.

In vitro effects of lipid emulsion on platelet function and thromboelastography in canine blood samples

To determine whether soybean oil emulsion has an in vitro effect on platelet aggregation and thromboelastography in blood samples obtained from healthy dogs. 12 healthy adult dogs. Blood samples were collected from each dog into tubes containing EDTA, hirudin, or sodium citrate for a CBC, collagen- and ADP-induced impedance aggregometry, or thromboelastography, respectively. Whole blood platelet aggregation, determined with ADP or collagen agonists, was measured in blood samples containing hirudin and final lipid concentrations of 0, 1, 10, and 30 mg/mL. The thromboelastographic variables R (reaction time), K (clotting time), α angle, and maximum amplitude were evaluated in blood samples containing sodium citrate and final lipid concentrations equivalent to those used for assessment of platelet aggregation. Median maximum ADP- and collagen-induced platelet aggregation in blood samples containing 1, 10, or 30 mg of lipid/mL did not differ significantly from the value for the respective lipid-free blood sample. Maximum amplitude determined via thromboelastography was significantly reduced in blood samples containing 10 and 30 mg of lipid/mL, compared with findings for lipid-free blood samples. Values of other thromboelastographic variables did not differ, regardless of lipid concentrations. Maximum amplitude determined via thromboelastography in canine blood samples was significantly affected by the addition of lipid to final concentrations that are several orders of magnitude higher than clinically relevant lipid concentrations in dogs. Lipid treatment appears to have no significant effect on hemostatic variables in dogs, although clinical studies should be performed to confirm these in vitro findings.

A crossflow filtration system for constant permeate flux membrane fouling characterization

Membrane fouling is often characterized using a crossflow filtration apparatus. Typically, the transmembrane pressure (TMP) difference is fixed, and the flux is allowed to decline as the membrane fouls and the resistance to mass transfer increases. However, as flux varies, so too does the rate at which foulants are brought to the membrane surface, so the observed fouling behavior is not solely the result of membrane∕foulant interactions. Constant flux experiments, where the permeate flux is fixed and the TMP difference varies, minimize such variations in the hydrodynamic conditions at the membrane surface, but constant TMP difference experiments dominate the fouling literature because they are more straightforward to execute than constant flux experiments. Additionally, most industrial water purification membrane installations operate at constant flux rather than at constant TMP. Here, we describe the construction and operation of a constant flux crossflow fouling apparatus. System measurement accuracy was validated by comparison of pure water permeance measurements to values specified by the membrane manufacturer, reported elsewhere, and measured by another technique. Fouling experiments were performed with two membrane∕foulant systems: polysulfone ultrafiltration membranes with a soybean oil emulsion foulant and PVDF microfiltration membranes with a polystyrene latex bead suspension foulant. Automatic permeate flux control facilitated flux stepping experiments, which are commonly used to determine the threshold flux or critical flux of a membrane∕foulant pair. Comparison of a flux stepping experiment with a literature report yielded good agreement.

Volatile Release from Self-Assembly Structured Emulsions: Effect of Monoglyceride Content, Oil Content, and Oil Type

Monoglycerides (MGs) can form self-assembled structures in emulsions, which can be used to control volatile release. In this study, initial headspace concentrations (C(initial)), maximum headspace concentrations (C(max)), release rates, and partition coefficients of propanol, diacetyl, hexanal, and limonene were determined in MG structured oil-in-water emulsions using dynamic and static headspace analyses. For all of the volatile compounds, C(initial) values above structured emulsions were significantly lower than those above unstructured emulsions and decreased with increasing MG contents (p < 0.05). However, volatiles had higher release rates in emulsions with higher MG contents. When oil content was reduced from 20 to 10%, C(initial) and C(max) increased for limonene and hexanal and decreased for propanol and diacetyl. When different oils were applied, both C(initial) and C(max) were significantly lower in medium-chain triglyceride emulsions than in soybean oil emulsions (p < 0.05). Static headspace analysis revealed that volatile compounds had significantly lower air-emulsion partition coefficients in the structured emulsions than in unstructured emulsions (p < 0.05). These results indicated that MG structured emulsions can be potentially used as delivery systems to modulate volatile release.