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A series of dicarboxylic-amylose inclusion complexes (AIC) were prepared by excess steam jet-cooking high amylose corn starch with linear C10, C12, C14, and C16 dicarboxylic acids to examine the influence of two polar head groups on complex formation. The C12, C14, and C16 dicarboxylic acid AIC were prepared in 48-63 % yields and contained 8.9-11.8 % diacid while the C10 AIC gave 30 % and contained 2.6 % diacid. These AIC had V6 helical amylose structures by XRD and complexation was further confirmed by DSC, FTIR, and TGA. SEM of the C12-C16 AIC revealed micron-sized toroidal spherulites while the C10 AIC was predominantly amorphous. DSC showed two AIC related transitions. This work provides a better understanding of the formation and physicochemical properties of these diacid AIC. Preparation by excess steam jet cooking demonstrates practical and commercial utility to prepare AIC as off-the-shelf materials for food and nonfood applications.

Antifungal compounds are of interest to reduce commodity spoilage and exposure to mycotoxins. In this study, a series of quantitative structure-activity relationship (QSAR) equations based on topological properties were developed to gain insight into the antifungal activities of phenolic compounds. The molecules were geometry optimized using B3LYP/6-311+G** density functional theory calculations. Analysis of the frontier orbital properties revealed that conjugated phenolic compounds possessed smaller band gap energies. Genetic function approximation (GFA) on populations of 100 one to two descriptor models over 10,000 generations identified several models for antifungal activity against Fusarium verticillioides, Fusarium oxysporum, Aspergillus flavus, Aspergillus fumigatus, Penicillium expansum, and Penicillium brevicompactum. Phenolic compounds with greater antifungal activity possessed a lower electrophilicity index. The correlation coefficients for the one and two descriptor models ranged from 0.627 to 0.790 and 0.762 to 0.939, respectively. Molecular descriptors associated with electrostatic and topological properties are important to describe the antifungal activities of the phenolic compounds studied.

To produce hydrochar with less volatile matter (VM) and more fixed carbon (FC) to increase its stability, this study compared the hydrothermal carbonization (HTC) of hen (HM) and swine (SM) manures at typical HTC sub-critical temperature of 210 °C and slightly super-critical temperature of 400 °C. Physico-chemical properties such as proximate analysis; ultimate analysis; Brunauer–Emmett–Teller (BET) surface area; higher heating value (HHV); chemical oxygen demand (COD); and inorganic nutrients of hydrochar, gaseous, and liquid products were determined. As expected, both VM and yield decreased with temperature. The heats of HTC reactions were estimated to be exothermic, ranging from −5.7 to −8.6 MJ/kg. The FC approximately doubled, while VM significantly decreased with a yield of 42.7%, suggesting the high potential of producing more stable hydrochar via near-critical HTC (NCHTC) treatment of SM. Additional work is needed before recommendations on carbonization temperatures can be made. Specifically, there is a need to experimentally investigate how the chars produced from each carbonization condition influence plant growth and soil emissions.

Mycotoxins, including zearalenone, are important natural products produced by fungi that occasionally contaminate agricultural commodities and pose serious health risks to consumers of food and feed. Zearalenone and its metabolite, α-zearalanol, are of significant concern due to their estrogenic and anabolic steroid activity. Several governments have regulatory standards and advisory guidelines for zearalenone and α-zearalanol. Raman and ultraviolet spectroscopy were employed with density functional theory methods to evaluate spectroscopic properties to distinguish between zearalenone and α-zearalanol systematically. Raman bands were assigned based on vibrational frequency calculations. A portable Raman spectroscopy instrument (785 nm laser) distinguished between zearalenone and α-zearalanol in a label-free manner. Many vibrational bands of zearalenone and α-zearalanol are similar, including high-intensity peaks at 1315 cm

Ochratoxin A is mycotoxin that can contaminate a variety of agricultural commodities, including fruit juices and wines. A detection method of ochratoxin A in grape juice and wine is reported that u...

A time-dependent density functional theory (TD-DFT) study was carried out on tautomers of the mycotoxin citrinin in the neutral, anionic, and cationic forms to gain insight into the role of chemical structure on detection. Steady-state fluorescence studies of citrinin in micellar aqueous solutions produced unusual results for ionic surfactants and the neutral Triton X-100 enhanced fluorescence emission. Ground-state and time-dependent density functional studies were carried out on five tautomers of citrinin using the B3LYP density functional and the 6-311+G(2df,2p) basis set. The investigation revealed that deprotonation is a major factor governing the shifts in fluorescence excitation and emission maxima. Moreover, the position of the lowest unoccupied molecular orbitals is removed from the fluorophore moiety of citrinin in the dianionic state which is consistent with the diminished fluorescence of the toxin in basic solutions. The ionic characteristics of certain chemosensors can influence the structure and intrinsic spectroscopic properties of citrinin.

Ferulic acid and its derivatives are important natural products found throughout the plant kingdom and are of special interest due to their health benefits. 1-Feruloyl-sn-glycerol (FG) and 1,3-diferuloyl-sn-glycerol (F2G) are two common bioproducts of ferulic acid that co-occur in nature and during the biocatalytic production of feruloylated lipids. In this paper, we report a comprehensive characterization of FG and F2G using Raman and UV spectroscopies and theoretical density functional theory calculations at the B3LYP/6-311+G** level. UV spectroscopy produced spectra for FG and F2G with similar peak shape, but difference intensities. The vibrational frequency calculations aided in the assignment of the Raman bands. The Raman analysis demonstrates that Raman spectroscopy is a rapid label free method to clearly distinguish between FG and F2G.

The synthesis of feruloylated coconut oil and feruloylated shea butter were demonstrated in 0.5-L scale, shaken, batch reactions. Ethyl ferulate and the vegetable oil/fat were combined in a 1.0:1.3 mol ratio in the presence of Candida antartica lipase B immobilized on an acrylic resin (Novozym 435) at 60 °C. The transesterification of ethyl ferulate with coconut oil and shea butter reached equilibrium conversions, after 22 days, of 63 and 70%, respectively, with the shea butter transesterifications producing a white precipitate not observed in the coconut oil transesterifications. The faster transesterification rates, equilibrium conversions and white precipitate were shown to result from di- and monoacylglycerols (DAG and MAG) present in the shea butter. The transesterification of ethyl ferulate and coconut oil was also tested in a continuous, enzymatic, packed-bed bioreactor using Novozym 435 at 60 °C to produce feruloylated coconut oil at rates of 0.5–0.9 kg/day over 4.5 months. The feruloylated coconut oil acylglycerol species were identified by LC–MS analysis of transesterification reactions of ethyl ferulate with medium chain triacylglycerol (TAG) standards, C8–C14. The feruloylated vegetable oils possessed an ultra violet (UV) absorbing λ max 328 nm, making them good UVAII absorbers, as defined by the U.S. Food and Drug Administration. The feruloylated coconut oil possessed a 17.5% higher absorption capacity than feruloylated shea butter on a per weight basis. All the feruloylated vegetable oils possessed rapid antioxidant capacity (50% reduction of initial radical concentration

Hydroxytyrosol and tyrosol phospholipids were enzymatically synthesized and investigated for their bilayer properties. Dynamic light scattering demonstrated that hand extrusion at 100nm consistently resulted in liposomes of nearly 85nm diameter for both phosphatidyl-hydroxytyrosol (DOPHT) and phosphatidyl-tyrosol (DOPT). Transmission electron microscopy showed DOPT and DOPHT liposomes extruded at 100-nm to be spherical and non-distinctive from one another. Zeta potential measurements resulted in surface charges-25mV, demonstrating both DOPT and DOPHT form highly stable liposomes. Quartz crystal microbalance with dissipation monitoring measurements demonstrated that liposomal adsorption was dependent on a combination of DOPT (or DOPHT) mole-percent and calcium ions concentration. Fluorescence anisotropy measurements indicated that melting temperatures of DOPT and DOPHT were below 4°C, suggesting that adsorption behavior and liposome formation was limited by electrostatic interactions and not gel-state formation.

Background: Feruloylated vegetable oil is a valuable green bioproduct that has several cosmeceutical applications associated with its inherent anti-oxidant and ultraviolet-absorption properties. Hydrolyzed vegetable oil by-products can influence product quality and consistency.; Results: The formation of by-products by residual water in the enzymatic synthesis of feruloylated vegetable oil was investigated using chemical theory and experimental studies by monitoring the reaction over a 22-day period. The hydrolysis of vegetable oil is thermodynamically favored over the hydrolysis of the ethyl ferulate starting material. These results suggest that hydrolyzed vegetable oil products will be experimentally observed in greater concentrations compared to hydrolyzed ethyl ferulate products.; Conclusion: Quantum chemical studies identified several reaction mechanisms that explain the formation of side products by water, suggesting that residual water influences product quality. Efforts to reduce residual water can improve product consistency and reduce purification costs. Published 2016. This article is a U.S. Government work and is in the public domain in the USA.; Published 2016. This article is a U.S. Government work and is in the public domain in the USA.

Amylose-ligand inclusion complexes represent an interesting approach to deliver bioactive molecules. However, ferulic acid has been shown not to form single helical inclusion complexes with amylose from high amylose maize starch. To overcome this problem a lipophilic ferulic acid ester, octadecyl ferulate, was prepared and complexed with amylose via excess steam jet cooking. Jet-cooking octadecyl ferulate and high amylose starch gave an amylose-octadecyl ferulate inclusion complex in 51.0% isolated yield. X-ray diffraction (XRD) and differential scanning calorimetry (DSC) confirmed that a 61 V-type inclusion complex was formed. Amylose and extraction assays showed the complex to be enriched in amylose (91.9±4.3%) and contain 70.6±5.6mgg(-1) octadecyl ferulate, although, minor hydrolysis (∼4%) of the octadecyl ferulate was observed under the excess steam jet-cooking conditions utilized. This study demonstrates that steam jet cooking is a rapid and scalable process in which to prepare amylose-octadecyl ferulate inclusion complexes.

The capacity of molecules to inhibit oxidation is widely tested using liposomes as host matrices of the antioxidant molecule of interest. Spectroscopic assays are readily used for this purpose, specifically assays using 2,2′-azobis(2-methylpropionamidine) dihydrochloride (AAPH). In this work the effect that charged lipids have on an AAPH antioxidation assay using 4,4-difluoro-5-(4-phenyl-1,3-butadienyl)-4-bora-3a,4a-diaza-s-indacene-3-undecanoic acid (C11-BODIPY® 581/591) as the reporter molecule was investigated. We measured the diameter, zeta potential and spectroscopic rate of decay and area-under-the-curve (AUC) associated with liposomes containing C11-BODIPY® 581/591 at varying molar percentages (0–10 mol%) of charged (cationic or anionic) lipids and compared the results. We showed that although increasing amounts of cationic or anionic lipids did change the diameter of the liposomes, size had little to no effect on the area-under-the-curve or decay rate of fluorescence. Increased (more positive) or decreased (more negative) zeta potentials did, on the other hand, affect the spectroscopic decay rates and area-under-the-curve. The results demonstrate the importance of considering the presence of charged lipids in the AAPH antioxidation assay.

Seven lipoate esters were synthesized by esterification of lipoic acid with different structures of alcohols in the presence of a solid acid catalyst and without solvent. The esters were obtained in good yield, characterized using 1H NMR and GPC; and their physical properties investigated. Four of the seven lipoate esters, with good solubility in high oleic sunflower oil (HOSuO) and polyalphaolefin (PAO6) base oils, were further investigated for their lubricant additive property. Additive properties were investigated in HOSuO base oil by varying the additive concentrations in the range 0–20 (w/w %). Properties investigated include: density; kinematic and dynamic viscosity; viscosity index (VI); oxidation stability from onset and peak oxidation temperatures on a PDSC; 4-ball antiwear (AW); and 4-ball extreme pressure (EP). Neat lipoate esters displayed high oxidation stability and high VI. As additives to HOSuO base oil, lipoate esters displayed good viscosity index improver (VII), good antioxidant, good e...

The synthesis of feruloyl soy glycerides was demonstrated on a pilot-scale (1 metric ton/year) in a continuous, four-column series, packed-bed, enzymatic bioreactor (herein referred to as the bioreactor). Ethyl ferulate and soybean oil were combined and converted at 3.5 kg/d over Candida antarctica lipase B immobilized on an acrylic resin (Novozym 435) at 60 °C. The ethyl ferulate/soybean oil substrate was fed through the four, packed-bed, enzyme columns in series with each column fitted with a recirculation pump, which improved conversion and throughput compared to smaller, batch bioreactor systems. The synthesis was carried out over 4.5 months with a single charge of enzyme to produce over 450 kg of feruloyl soy glycerides at 65% conversion. The stability of the feruloyl soy glycerides was determined by comparing the total ferulate concentration (UV absorbance), free radical scavenging (antioxidant) capacity, total acid value (hydrolysis), and Lovibond color of samples produced in 2009 to samples produced in 2015. The feruloyl soy glycerides showed no appreciable loss of UV absorbing ( λ max 325 nm) or rapid antioxidant capacity (50% reduction of initial radical concentration

The phenols hydroxytyrosol and tyrosol made abundantly available through olive oil processing were enzymatically transesterified into effective lipophilic antioxidants with cuphea oil. The hydroxytyrosyl and tyrosyl esters made from cuphea oil were assessed for their ability to partition into, locate within and effect the bilayer behavior of 1,2-dioloeoylphosphatidylcholine liposomes and compared to their counterparts made from decanoic acid. Partitioning into liposomes was on the same scale for both hydroxytyrosyl derivatives and both tyrosyl derivatives. All were found to locate nearly at the same depth within the bilayer. Each was found to affect bilayer behavior in a distinct manner.

Lesquerella (LO) and castor oil (CO) were esterified at the secondary hydroxyl groups of their 14-hydroxyeicos-cis-11-enoic fatty acids and 12-hydroxyoctadec-cis-9-enoic fatty acids, respectively, with 4-acetoxy-3-methoxycinnamic acid (acetoxyferulic acid). The unconventional esterifications were conducted under inert nitrogen atmospheres without solvent at 175–200 °C in sealed ampules. 1H NMR was used to measure the degree of acetoxyferuloyl esterification using a modified esterification number (EN). Reactions at 200 °C resulted in ∼43% conversions to the acetoxyferuloylated LO and CO but promoted significant degradation/loss of the acetoxyferulic acid as evidenced by the low quantity of acetoxyferulic acid found in the reaction products as determined by HPLC. Reactions at 175 °C resulted in significantly lower conversions to the acetoxyferuloylated LO and CO, 9–17%, but did not result in as severe acetoxyferulic acid degradation. The addition of tin (II) 2-ethylhexanoate catalyst to the 175 °C reactions increased esterification conversion to ∼45% without significant loss of acetoxyferulic acid to degradation. The aromatic acetate of the acetoxyferuloylated LO and CO was selectively deacylated using excess pyrrolidine without affecting the aliphatic esters to give feruloylated LO and CO. The feruloylated LO and CO absorbed ultraviolet (UV) radiation from 280 to 360 nm with a λmax at 327 nm, bridging the absorbance gap of commercial UV absorbing ingredients. The feruloylated LO and CO are also presumably good antioxidants and are potential candidates for incorporation into lipid bilayers to protect liposomes and their contents from reactive oxygen species.

Manure-derived biochar is the solid product resulting from pyrolysis of animal manures. It has considerable potential both to improve soil quality with high levels of nutrients and to reduce contaminants in water and soil. However, the combustible gas produced from manure pyrolysis generally does not provide enough energy to sustain the pyrolysis process. Supplementing this process may be achieved with spent agricultural plastic films; these feedstocks have large amounts of available energy. Plastic films are often used in soil fumigation. They are usually disposed in landfills, which is wasteful, expensive, and environmentally unsustainable. The objective of this work was to investigate both the energetics of co-pyrolyzing swine solids with spent plastic mulch films (SPM) and the characteristics of its gas, liquid, and solid byproducts. The heating value of the product gas from co-pyrolysis was found to be much higher than that of natural gas; furthermore, the gas had no detectable toxic fumigants. Energetically, sustaining pyrolysis of the swine solids through the energy of the product gas could be achieved by co-pyrolyzing dewatered swine solids (25%m/m) with just 10% SPM. If more than 10% SPM is used, the co-pyrolysis would generate surplus energy which could be used for power generation. Biochars produced from co-pyrolyzing SPM and swine solid were similar to swine solid alone based on the surface area and the (1)H NMR spectra. The results of this study demonstrated the potential of using pyrolysis technology to manage two prominent agricultural waste streams (SPM and swine solids) while producing value-added biochar and a power source that could be used for local farm operations.

Lipoyl glycerides were synthesized by enzymatic transesterification of lipoic acid with high-oleic sunflower oil in 2-methyl-2-butanol solvent. The synthesis gave a crude product mixture comprising unreacted lipoic acid, free fatty acids, and several lipoyl glyceride structures of varying lipoic acid substitution. A more purified product mixture, devoid of unreacted lipoic acid and free fatty acids, was obtained in 61% yield. The crude and purified product mixtures were thoroughly characterized and their components positively identified. The tribological properties of the product mixtures were further investigated using a variety of methods. The product mixtures displayed significantly improved oxidation stability, cold-flow, and extreme pressure properties over those of the parent high-oleic sunflower oil. The extreme pressure results for the neat products showed a higher weld point for the crude than for the purified mixture. This was attributed to differences in the chemical properties of the components in the two product mixtures.

Polyanionic polymers and liposomes have a great potential use as individual drug delivery systems and greater potential as a combined drug delivery system. Thus, it is important to better understand the interactions of polymers with phospholipid bilayers. A mechanistic study of the interaction between carboxyl-terminated poly(amidoamine) (PAMAM) dendrimers with 1-palmitoyl-2-oleoyl-phosphatidylcholine (POPC) bilayer using fluorescence leakage and quartz crystal microbalance with dissipation monitoring (QCMD) was conducted. Fluorescence leakage experiments demonstrated that carboxyl-terminated generation 2 (G2-COOH) dendrimers caused increased liposome leakage with increasing dendrimer concentration over a 0 to 20 μM range. Generation 5 (G5-COOH), on the other hand, reduced leakage over the same concentration range, presumably by increasing lipid packing. QCMD and atomic force microscopy (AFM) measurements demonstrated that G2-COOH interacting with supported bilayers resulted in small defects with some mass loss and no adsorption. In contrast, G5-COOH interaction with a bilayer resulted in adsorption and local bilayer swelling.

2-Monoricinoleoylglycerol (2-MRG) was synthesized by the Novozym 435 catalyzed alcoholysis of castor oil in excess ethanol (1:70 mol:mol) at ambient temperature. Due to the fatty acid C12-OH group, conventional liquid–liquid extraction methods developed for less polar, non-hydroxylated 2-monoacylglycerols (2-MAG) proved inadequate for 2-MRG purification. Alternatively, 2-MRG was purified by normal-phase flash chromatography (FC) on silica gel using a binary acetone-hexane gradient mobile phase. Gram quantities of 2-MRG were isolated in 63 % yield and contained no residual diacylglycerol (DAG), which fail to separate using liquid–liquid extraction methods. The 2-MRG was obtained at ~90 mol% relative to 1-MRG, proving that the FC method did not appreciably catalyze acyl migration. 1H-NMR spectroscopy was used to monitor the spontaneous acyl migration of isolated 2-MRG from 20 to 80 °C. The relative energy of activation calculated from the Arrhenius relationship of the 2-MRG acyl migration rate constants was 82.9 kJ/mol. This was ~two-fold higher than the theoretical ΔG298.15 calculated from molecular modeling using density functional calculations (B3LYP/6−31 + G*) of 2-MRG, the ketal ring transition state, and 1-monoricinoleoylglycerol (1-MRG). The synthesis and isolation methods reported herein provide a convenient means to access useful intermediates for functionalized structured lipids.

Soybean oil 2-monoacylglycerol (2-MAG) was synthesized via the Novozym 435-catalyzed ethanolysis of triacylglycerols and purified by conventional liquid–liquid extraction. The 2-MAG was subjected to incubation at 20 and 40 °C in the presence of five solid commercial support materials, Lewatit, Silica Gel 60, Alumina–Neutral Brockman Activity 1, Amberlyst-15, and SBA-15, to determine their effects on acyl migration rates. Lewatit and SBA-15 did not catalyze acyl migration rates after 144 h, while silica gel slightly increased migration rates. The more polar alumina and the cationic Amberlyst 15 significantly increased migration rates. Flash chromatography purification of 2-MAG using silica gel as the immobile phase developed with an acetone/hexane binary gradient proved to be a comparable purification method to liquid–liquid extraction, resulting in 60 % 2-MAG yield, no residual triacylglycerol, diacylglycerol, or glycerol co-products, and a 95 mol% 2-MAG purity vs. 1-MAG, demonstrating that flash chromatography did not catalyze acyl migration.

Effective lipophilic antioxidants were prepared by non-aqueous enzymatic transesterification of plant phenols with cuphea oil. Tyrosol and hydroxytyrosol, abundantly available phenols from olive oil processing byproduct, were found to be predominately acylated with capric acid derived from the triglyceride fraction of the Cuphea germplasm line PSR 23 (Cuphea Viscosissima × C. lanceolata). The reaction was complete within 2 h, with a >97% conversion of either phenol using immobilized Candida antarctica lipase B. The reaction products were good solvents for tyrosol or hydroxytyrosol, suggesting a facile manufacturing route not dependent on use of organic solvents. Phenolic derivatives were assessed for their ability to serve as antioxidants for preventing the oxidation of polyunsaturated fatty acyl groups. The antioxidant capacities of the cuphea-derived fatty acyl derivatives of tyrosol or hydroxytyrosol were the same as their respective derivatives prepared from decanoic acid. These biobased antioxidants may improve the oxidative stability of sensitive fatty acids in food applications. Practical applications: A new biobased antioxidant was created for the food industry. Foods can contain fats and oils that are susceptible to deterioration during storage, which can limit product quality and shelf-life. Synthetic antioxidants can slow the spoilage process, although there are limitations to how much can be added to foods. The food industry is interested in using natural ingredients to solve storage stability problems. We found that the oil from the plant Cuphea, cultivated in the upper Midwest region of the US, is very useful for modifying olive oil waste molecules to create antioxidants for use in foods. The developed process would be suitable for commercial production. This research creates a new commercial use for a specialty oil seed crop, expands the market for cuphea oil, and has developed two novel antioxidants to help the food industry improve food quality.

Feruloylated vegetable oil is a valuable green bioproduct that has several cosmeceutical applications associated with its inherent anti-oxidant and ultraviolet-absorption properties. Hydrolyzed vegetable oil by-products can influence product quality and consistency.The formation of by-products by residual water in the enzymatic synthesis of feruloylated vegetable oil was investigated using chemical theory and experimental studies by monitoring the reaction over a 22-day period. The hydrolysis of vegetable oil is thermodynamically favored over the hydrolysis of the ethyl ferulate starting material. These results suggest that hydrolyzed vegetable oil products will be experimentally observed in greater concentrations compared to hydrolyzed ethyl ferulate products.Quantum chemical studies identified several reaction mechanisms that explain the formation of side products by water, suggesting that residual water influences product quality. Efforts to reduce residual water can improve product consistency and reduce purification costs. Published 2016. This article is a U.S. Government work and is in the public domain in the USA.

The effect of desaturation from the C9 to the C15 carbon of 2-monoacylglycerol (2-MAG) fatty acids on spontaneous acyl migration is described. Three 2-MAG species, 2-monooleoylglycerol (C18:1 cis-Δ9), 2-monolinoleoylglycerol (C18:2 cis-Δ9,12), and 2-monolinolenoylglycerol (C18:3 cis-Δ9,12,15) were synthesized by lipase-catalyzed ethanolysis of their respective triacylglycerols and isolated in >60 % yield and at 2-MAG purities of >95 % relative to 1-monoacylglycerol (1-MAG). 1H-NMR spectroscopy was used to monitor the spontaneous acyl migration of the 2-MAG species over a temperature range from 20 to 80 °C. The relative energies of activation calculated from the Arrhenius relationships of the 2-MAG acyl migration rate constants were 73.3, 68.0, and 72.9 kJ mol−1 for the three 2-MAG species, respectively. Density functional calculations performed using the B3LYP functional at the 6-31+G* basis set on the three ketal ring intermediate of the three 2-MAG species followed a similar trend with a lack of relative energetic preference associated with the degree of desaturation. The kinetically determined relative activation energies were approximately twofold higher than the theoretical relative Gibbs free energies of the intermediates, suggesting that other factors influence acyl migration. In general, increasing desaturation after the C9 carbon of 2-MAG fatty acids had no appreciable effect on acyl migration rates.

Ferulic acid and its esters are known to be effective antioxidants. Feruloyl di-γ-linolenoylglycerol was assessed for its ability to serve as an antioxidant for preventing the oxidation of its γ-linolenoyl polyunsaturated fatty acyl groups in model membrane phospholipid vesicles. The molecule was incorporated into single-lamellar vesicles comprised of 1,2-dioleoyl-sn-glycero-3-phosphocholine. Feruloyl di-γ-linolenoylglycerol was found to be highly resistant to 2,2′-azobis(2-amidinopropane) dihydrochloride-initiated oxidation in comparison to di-γ-linolenoylglycerol. Analysis of the individual fatty acyl chains indicated that degradation of γ-linolenoyl groups from feruloyl di-γ-linolenoylglycerol proceeded much more slowly than loss of the entire molecule, indicating that the feruloyl moiety was preferentially oxidized. In vesicles incorporating di-γ-linolenoylglycerol and an equal amount (5 mol% each) feruloyl dioleoylglycerol, the extent of γ-linolenoyl protection was not as great as when the γ-linolenoyl groups were molecularly combined with a ferulate group. These findings indicate that the ferulate group of feruloyl di-γ-linolenoylglycerol expresses intramolecular antioxidant activity. Direct coupling of polyunsaturated fatty acids with phenolic antioxidants may improve the oxidative stability of sensitive fatty acids in food or topical uses.

The natural plant components, 1-feruloyl- sn -glycerol (FG) and 1,3-diferuloyl- sn -glycerol (F 2 G), were synthesized by the enzymatic esterification of glycerol and soybean oil mono- and diacylglycerols, respectively, with ethyl ferulate. The isolated FG and F 2 G were examined for their antioxidant activities as free radical scavengers (DPPH assay) and peroxyl lipid oxidation inhibitors (TBARS assay). The H atom transfer kinetics, as monitored by DPPH free radical bleaching, of FG showed that the mono-feruloyl glycerol acted as a rapid antioxidant (50% reduction of DPPH radical 2 G and ferulic acid activity rates were in the range of intermediate antioxidants (50% reduction of DPPH radical in 5–30 min). FG and F 2 G showed similar activity as the control agent, ethyl ferulate, towards the inhibition of the AAPH-induced peroxyl radical oxidation of surfactant emulsified γ-linolenic acid. A slight excess of feruloyl groups was sufficient to completely suppress the formation of secondary lipid oxidation products.

The fatty acid moiety of 2-monoacyl-sn-glycerol (2-MAG) undergoes spontaneous acyl migration to the sn-1(3) position, resulting in a thermodynamic equilibrium of approximately 1:9 of 2-MAG to 1(3)-monoacyl-sn-glycerol (1-MAG). Spontaneous acyl migration is an impediment to synthesizing and isolating specific 2-MAG for use as intermediates in the synthesis of structured triacylglycerols. 2-Monooleoyl-sn-glycerol was synthesized by the enzymatic ethanolysis of triolein and isolated by liquid CO2 extraction. The resultant MAG, diacylglycerol, and fatty acid ethyl esters were quantified by 1H NMR and supercritical fluid chromatography. The low polarity of the CO2 and mild extraction temperature (25 °C) resulted in very low spontaneous acyl migration rates, allowing the MAG to be isolated in 80% yield and in a very high 2-MAG:1-MAG ratios of ≥93 mol%.

Triacylglycerols containing a high abundance of unusual fatty acids, such as γ-linolenic acid, or novel arylaliphatic acids, such as ferulic acid, are useful in pharmaceutical and cosmeceutical applications. Candida antarctica lipase B (CALB) is quite often used for non-aqueous synthesis, although the wild-type enzyme can be rather slow with bulky and sterically hindered acyl donor substrates. The catalytic performance of a circularly permutated variant of CALB, cp283, with various acyl donors and glycerol was examined. In comparison to wild-type CALB, butyl oleate and ethyl γ-linolenate glycerolysis rates were 2.2- and 4.0-fold greater, respectively. Cp283 showed substrate inhibition by glycerol, which was not the case with the wild-type version. With either ethyl ferulate or vinyl ferulate acyl donors, cp283 matched the performance of wild-type CALB. Changes in active site accessibility resulting from circular permutation led to increased catalytic rates for bulky fatty acid esters but did not overcome the steric hindrance or energetic limitations experienced by arylaliphatic esters.

Two mesoporous silicas functionalized with propylsulfonic (SBA-15-PSA) and arenesulfonic (SBA-15-ASA) acid groups, and a highly acidic, functionalized styrene divinylbenzene copolymer ion exchange resin (Amberlyst-15) were examined for their ability to catalyze the ethanolic esterification of the ω-sulfhydryl fatty acid, 11-mercaptoundecanoic acid (MUA), without catalyzing unwanted side reactions at the sulfhydryl group. All three solid acid catalysts catalyzed the MUA esterification in excess ethanol. The activation energy for the catalytic esterifications were determined from 50 to 75 °C, resulting in apparent E a of 54, 71, and 59 kJ/mol for SBA-15-PSA, SBA-15-ASA, and Amberlyst-15, respectively. GC–MS analysis determined that all three catalysts produced near quantitative conversion of MUA to its ethyl ester with very little reactivity towards the sulfhydryl group. This was a marked improvement over the esterifications catalyzed by sulfuric and p-toluenesulfonic acids which produced thioethers and disulfide side products. The MUA ethyl ester synthesis was demonstrated on a gram scale at 70 °C catalyzed by Amberlyst-15, and the desired product was isolated in 80% yield at >95% purity with a minimum of purification.

The pyrolytic conversion of oak sawdust at 500 °C in flowing He over eight proprietary catalysts is described and compared to the control bed material, quartz sand. The reactions were conducted and compared in two reactors, an analytical, μg-scale pyroprobe reactor and a bench, g-scale packed bed reactor. The catalysts examined were modified acid catalysts, dealuminated-zeolite Y, β-zeolite, a naturally occurring metal hydroxide containing mineral, mordenite, and a mesoporous aluminosilicate molecular sieve. The packed bed reactor allowed the collection of three bulk product fractions, char, liquid, and gas, all of which could not be obtained from the μg-scale pyroprobe reactions. The catalysts effect on the mass balance of the bulk fractions tended toward more chars and less liquid compared to the sand control. The catalysts’ effects on the liquid products obtained in both reactors shifted away from acetic acid, furfural and higher molecular weight phenolics obtained with sand to lower molecular weight aromatics. This halved the total acid number of the liquid fraction and raised the pH by up to 1.4 units. The modified catalysts’ effects on the gas products from both reactors did not follow a specific trend. Instead, specific catalysts were able to enrich specific gas species up to a factor of 15 while suppressing the formation of others compared to the sand control. Two catalysts, β-zeolite and a naturally occurring metal hydroxide containing mineral, were regenerated and recycled up to five times with no loss of activity.

The pyrolytic conversion of pure lignin at 600 °C in flowing helium over five catalysts is described and compared to the control bed material, sand. Product distribution as char, liquid, and gas are described as well as the composition of the liquid and gas fractions. The catalysts examined were HZSM-5, KZSM-5, Al-MCM-41, solid phosphoric acid, and a hydrotreating catalyst, (Co/Mo/Al 2 O 3 ). The sand yielded a liquid phase that was 97% oxygenated aromatics and a gas phase that was CO (18 vol%), CO 2 (16 vol%), and CH 4 (12 vol%). HZSM-5 was the best catalyst for producing a deoxygenated liquid fraction yielded almost equal amounts of simple aromatics (46.7%) and naphthalenic ring compounds (46.2%). The gas phase over this catalyst consisted of CO (22 vol%), CO 2 (14 vol%), H 2 (12 vol%), and CH 4 (10 vol%). The Co/Mo/Al 2 O 3 hydrotreating catalyst yielded a liquid consisting of 21% aromatics, 4% naphthalenics, and 75% oxygenated aromatics and a gas phase that was rich in hydrogen: H 2 (18 vol%), CO 2 (16 vol%), CO (12 vol%), and CH 4 (8 vol%).

1,3-Diferuloyl-sn-glycerol is found ubiquitously throughout the plant kingdom, possessing ultraviolet adsorbing and antioxidant properties. Diferuloyl glycerol was synthesized and isolated as a byproduct in up to 5% yield from a pilot plant scale packed-bed, biocatalytic transesterification of ethyl ferulate with soybean oil or mono- and diacylglycerols from soybean oil. The yield of the diferuloyl glycerol byproduct was directly proportional to the overall water concentration of the bioreactor. The isolated diferuloyl glycerol exhibited good ultraviolet adsorbing properties, 280-360 nm with a lambda(max) 322 nm, and compared well to the efficacy of commercial sunscreen active ingredients. The antioxidant capacity of diferuloyl glycerol (0.25-2.5 mM) was determined by its ability to scavenge 2,2-diphenyl-1-picrylhydrazyl radicals and was comparable to that of ferulic acid. At current pilot plant scale production capacity, 120 kg diferuloyl glycerol byproduct could be isolated per year.

A liquid carbon dioxide counter-current fractionation method was developed to remove by-product fatty acid propyl esters (FAPEs) from the reaction mixture after the partial deacylation of sunflower oil. The fractionation column was 1.2 m long and separations were done at 25 °C and 8.27 MPa. Several solvent to feed ratios (S:FR) (i.e., 7.6, 15.2, 30.3 and 60.6 g/g) and feed rates (FR) (i.e., 1, 2, 2.5, 3 and 4 mL/min) at a constant S:FR of 15.2 were examined. Raffinate purity (i.e., percentage glycerides) and extract purity (i.e., percentage FAPEs) were both monitored. Percentage glycerides in both the raffinate and the extract increased with S:FR. The raffinate contained ca. 83, 97, 100 and 100% glycerides at S:FRs of 7.6, 15.2, 30.3 and 60.6, respectively. The percentage glycerides in the extracts were ca. 3, 4, 8 and 17%, respectively. With the S:FR held constant at 15.2, the raffinate purity peaked at ca. 99% glycerides at a FR of 2.5 mL/min and the extract at this FR contained ca. 96% FAPEs. The optimal S:FR and FR determined from the experimental assays was applied to large batches in both a semi-continuous feed mode, and later in a continuous feed mode, which gave raffinates of 99.3 and 98.1% glycerides, respectively, and extracts of 97.3 and 97.2% FAPEs, respectively.

High oleic sunflower oil (HOSO) and soybean oil (SBO) were partially deacylated by enzyme-catalyzed propanolysis using lipozyme TL IM to form 1,2-diacyl- sn -glycerols (1,2-DAG) in 40% yields. 1,2-DAG are of interest as potential regiospecific intermediates in the synthesis of structured lipids for cosmeceutical and nutriceutical applications. Two purification techniques were examined to determine which was the most efficient at removing the fatty acid propyl ester (FAPE) byproducts while limiting the spontaneous acyl migration of the 1,2-DAG to 1,3-diacyl- sn -glycerols (1,3-MAG) and adversely affecting the physical properties of the 1,2-DAG and FAPE. Molecular distillation of the partially deacylated vegetable oils was examined at temperatures ranging from 120 to 240 °C. Molecular distillation at 220 °C removed 77% of the FAPE byproduct but caused significant acyl migration. Additionally, the acid values and Lovibond color of the partially deacylated vegetable oils were deleteriously affected. The purity of the FAPE, contaminated by co-distillation of di- and mono-acylglycerol species as monitored by viscosity values and 1 H NMR, was also compromised by the high temperature distillation. Distillations at lower temperatures improved the physical properties of the partially deacylated vegetable oils and the purity of the FAPE but at the sacrifice of the efficiency of FAPE removal. The mild condition of the liquid CO 2 extraction afforded the most efficient removal of the FAPE, 96%, while causing no appreciable acyl migration, and resulted in acid values and Lovibond colors comparable to those obtained at the lowest molecular distillation temperatures studied.

The acyl migration kinetics of long-chain 1,2-diacylglycerol (1,2-DAG) to form 1,3-diacylglycerol (1,3-DAG) over the temperature range of 25–80 °C were examined using 1H-NMR spectroscopy. Lipase-catalyzed ethanolysis of high-oleic sunflower oil, followed by a series of solvent extraction steps, generated high purity 1,2-DAG (0.93 mol fraction of the DAG content). The 1,2-DAG mole fraction of 0.32 at equilibrium was found to be insensitive to temperature, indicating that long-chain acyl group migration is neither endothermic nor exothermic. Determination of the temperature-dependent, first-order reaction kinetic parameters revealed a 1,2-DAG half life (t 1/2) of 3,425 h and 15.8 h at 25 and 80 °C, respectively. A comparison of 1,2-DAG with 2-monoacylglycerol indicated that there is no difference between the two in the potential energy state (ΔG ‡) of their respective transitions states or cyclic intermediates.

The enzymatic reaction of soybean oil (SBO) triacylglycerides (TAGs) with ethyl ferulate (EF) produces the product feruloylated acylglycerols, called SoyScreen™ as well as by-product fatty acid ethyl esters (FAEEs). Both the unreacted EF as well as the by-product FAEEs must be removed from the mixture before the feruloylated acylglycerols can be used as natural sunscreens and/or antioxidants. This research investigated the use of a continuous liquid carbon dioxide (L-CO 2 ) counter-current fractionation method to purify a model mixture representing the crude enzymatic mixture from the synthesis of SoyScreen™. The effect of column length, solvent to feed ratio (S:FR) and feed rate were examined. Raffinate purity increased with both column length and S:FR. When the feed rate was doubled while the S:FR was held constant, there was essentially no loss of raffinate purity. Using L-CO 2 (23–25 °C and 11.0 MPa), a 120 cm long packed column, a S:FR of ca. 11.9, the raffinate was essentially free of both EF and FAEEs at feed rates of either 0.464 or 0.927 g/min with ca. 90% yield.

The acyl migration kinetics of neat 2-monoacylglycerol (2-MAG) to form 1-MAG was determined using 1H NMR spectroscopy to monitor the β-proton integration ratios of the two species over time. 2-MAG was synthesized by the Novozym 435-catalyzed alcoholysis of soybean oil and isolated by solvent extraction or molecular distillation at a mole fraction (X 2-MAG) of 0.94 relative to total MAG. The kinetics parameters of the neat 2-MAG acyl migration were investigated over the temperature range of 23–80 °C. The 2-MAG mol fraction remained unchanged at 23 °C over the course of 168 h and reached an equilibrium of X 2-MAG = 0.09 at only 80 °C. Modeling of the kinetics data revealed a 2-MAG half life (t 1/2) of 3,500 and 22.8 h at 23 and 80 °C, respectively, with an activation energy of 79.0 ± 6.5 kJ mol−1. The use of 1H NMR spectroscopy proved an expedient method for monitoring the acyl migration in 2-MAG compared to other reported methods (e.g. GC, HPLC, and 13C-NMR spectroscopy), requiring no sample manipulation and minimizing the deleterious effects of high temperatures and solvent exposure.

Ferulic acid is a hydroxy cinnamic acid derivative found ubiquitously throughout the plant kingdom, is especially abundant in rice and corn bran, and possesses excellent ultraviolet (UV) and antioxidant properties. Ferulic acid was enzymatically incorporated into soybean oil to form feruloylated monoacyl- and diacylglycerols (FAG). The FAG possess the UV-absorbing and antioxidant properties of ferulic acid but are water insoluble and extremely lipophilic. These characteristics make FAG attractive in the cosmeceutical industry as an all-natural replacement for petroleum-based sunscreen active ingredients and antioxidants. The FAG were synthesized from the transesterification of soybean oil with ethyl ferulate catalyzed by the commercial lipase, Novozym 435 (Candida antartica lipase B). The FAG were encapsulated as microdroplets within a starch matrix via steam jet cooking (140 °C and 225 kPa). Up to 50% (w/w) of the feruloylated lipids was encapsulated into the starch matrix with the microdroplets ranging in size from 1 to 10 μm. Transmittance and irradiance measurements of UV radiation (300–400 nm) through thin films of neat FAG (not manipulated after FAG synthesis) and starch-encapsulated FAG showed that the FAG retained its ultraviolet-absorbing efficacy after steam jet cooking. Furthermore, starch-encapsulation of the FAG was found to enhance the ultraviolet absorbance of the feruloylated lipids. When encapsulated at 50% (w/w) in the starch matrix, one-half of the coverage (mg/cm2) of FAG was required to block the same amount or more UV radiation as neat FAG. The starch-encapsulated FAG was formulated as an aqueous dispersion without the need for emulsifiers or surfactants. The dispersions were drum dried to a powder and shown to be easily reconstituted into water dispersions without the loss of ultraviolet-absorbing efficacy.

The use of HPLC-MS to separate and identify the feruloylated acylglycerols formed during the transesterification of ethyl ferulate with TAG was examined. Novozym 435 (Candida antarctica lipase B)-catalyzed transesterifications of ethyl ferulate and soybean oil resulted in a mixture of feruloylated MAG, DAG, and TAG and diferuloylated DAG and TAG. These feruloylated acylglycerols have recently garnered much interest as cosmeceutical ingredients. The ratio of the various feruloylated acylglycerol species in the resultant oils is presumed to affect the oil's cosmetic efficacy as well as its physical (formulation) properties. Thus, it was desirable to develop an analytical method to separate, identify, and quantify the individual feruloylated acylglycerols to determine their relative ratios. The feruloylated acylglycerols were successfully separated and identified by HPLC-MS using a phenyl-hexyl reversed-phase column developed with a water/methanol/1-butanol gradient. The chromatograms of the feruloylated acylglycerols from soybean oil were convoluted by myriad fatty acids; therefore, feruloylated acylglycerols from triolein were studied as a model reaction. Hydrolysis of the feruloylated acylglycerols from triolein catalyzed by Lipase PS-C “Amano” I (Burkholderia cepacia), which showed no hydrolysis reactivity toward ethyl ferulate, allowed for the chromatographic assignment of the feruloyl acylglycerol positional isomers.