Artemisia phaeolepis, a perennial herb with a strong volatile odor, grows on the grasslands of Mediterranean region. Essential oil obtained from Artemisia phaeolepis was analyzed by gas chromatography-flame ionization detection and gas chromatography-mass spectrometry. A total of 79 components representing 98.19% of the total oil were identified, and the main compounds in the oil were found to be eucalyptol (11.30%), camphor (8.21%), terpine-4-ol (7.32%), germacrene D (6.39), caryophyllene oxide (6.34%), and caryophyllene (5.37%). The essential oil showed definite inhibitory activity against 10 strains of test microorganisms. Eucalyptol, camphor, terpine-4-ol, caryophyllene, germacrene D and caryophyllene oxide were also examined as the major components of the oil. Camphor showed the strongest antimicrobial activity; terpine-4-ol, eucalyptol, caryophyllene and germacrene D were moderately active and caryophyllene oxide was weakly active. The study revealed that the antimicrobial properties of the essential oil can be attributed to the synergistic effects of its diverse major and minor components.
Refined olive oil has been analyzed in order to evaluate the influence of storage time on their quality after enrichment with chlorophyll pigments and squalene. At the end of the storage, chlorophyll pigments decomposed for more than 90%, while, carotene pigment loss was lower showing up to 75% in all oil samples stored at 20°C and 50°C. The reduction of total phenolic compounds exhibited similar degradation profiles, reducing by 81% for enriched refined olive oil stored at 20°C and 50°C after six months. For all studied samples, squalene content decreased significantly (p< 0.05) only after four months of storage. Oils with added pure squalene had the lower peroxide values (52 meq O2 · kg–1) at the end of storage at 20°C. After six months of storage the oxidative stability increased to 1 h 28 min and 2 h 06 min for refined olive oil stored at 20°C enriched with chlorophyll + squalene and only by squalene, respectively. Therefore, squalene supplemented with 800 mg · kg–1 exhibited favorable antioxidant effects and is preferable for effectively avoiding oxidation. This study could provide useful information for industry to produce high-stability vegetable oil.
The relation between oxygen content and oxidation was investigated in frying oils. When canola oil, a canola-soybean oil blend or a trioctanoylglycerol (glycerol tricaprate) sample were heated with stirring, their dissolved oxygen content decreased abruptly at about 120°C and the carbonyl values (CV) increased gradually with heating and reached values of 6-7 at 180°C in the blended and canola oils, while the CV of trioctanoylglycerol was zero up to 150°C. Probably this abrupt decrease in oxygen content above 120°C can be attributed to the solubility of oxygen in oil rather than because of oxidative reactions. The oxygen content of oil that has been stripped of part of its oxygen, increased at temperatures between 25 and 120°C. In oils that have lost their oxygen by being heated to 180°C, standing at room temperature will slowly restore their oxygen content as the oil cools. Intermittent simple heating of oil promoted oxygen absorbance during cooling periods and standing times, and it resulted in an elevated content of polar compounds (PC). Domestic deep-frying conditions also favor the presence of oxygen in oil below 120°C and during the oil’s long standing at room temperature. The oxygen content in oil was low during deep-frying, but oxidation was active at the oil/air interface of bubbles generated by foods being fried. Repeated use of oil at temperatures between 25-180°C resulted in oil with low oxygen values.
We examined the fecal fat excretion of mildly hypertriacylglycerolemic subjects who ingested soft cookies containing 1(3)-behenoyl-2,3(1)-dioleoyl-rac-glycerol (BOO) for 7 days. The subjects included 14 healthy men (average age; 44.9 ± 1.7) whose fasting plasma triacylglycerol level ranged from 150 to 250 mg/dL. Every day for 7 days, the subjects ate 5 soft cookies containing margarine with the BOO-rich experimental oil (BOO intake, 2.46 g/day). The placebo group ate soft cookies containing margarine without BOO. This study was a randomized double-blind, placebo-controlled, crossover study. Feces were collected for 3 days prior to the end of the treatment period, and fecal fat and fatty acid composition were determined. The fecal wet weight was significantly increased in BOO group compared with that in the placebo group. Moreover, fecal fat and fatty acid level were significantly higher in the BOO group than in the placebo group. There were no significant differences in the fecal fatty acid composition of the BOO and placebo groups. These results suggest that dietary BOO increases fecal excretion of dietary fat in humans. However, BOO does not increase the excretion of specific fatty acids; it increases the excretion of all fatty acids of dietary origin, which may lead to lower and delay intestinal absorption of dietary fat.
Methyl linoleate and α-linolenate were used as representative n-6 and n-3 polyunsaturated fatty acid esters, respectively, to examine the effect of oil droplet size on autoxidative stability in oil-in-water systems. The emulsions, which were prepared via membrane emulsification and had a mean oil droplet size of approximately 1–30 μm, and had a stable size during the autoxidation of each substrate at 55°C. The autoxidation of methyl linoleate did not depend on oil droplet size during the entire process and that of methyl α-linolenate was independent of oil droplet size during the first half of the autoxidation process. However, the autoxidation rate of methyl α-linolenate proceeded faster in the emulsion with smaller oil droplet size during the last half of the autoxidation process.
It has been previously shown that the positional isomers of triacylglycerol (TAG) containing palmitic acid (P) and highly unsaturated fatty acids (HUFAs) such as DHA (D) and EPA (E) vary between fishes and marine mammals. However, it has not yet been understood why in marine mammals HUFAs are located only at the α position when two palmitic acid chains combine, and not in fishes. In order to gain further understanding of the biosynthetic pathways involved in the formation of these asymmetric TAGs, we investigated whether the HUFA in the TAG of marine mammals exists predominantly at the sn-1 or sn-3 position. We examined the TAG positional isomers and enantiomers in marine organisms in detail. As a result, while PDP and PEP were not detected, sn-PPD and sn-PPE were found in abundance in marine mammals. For fishes, on the other hand, PDP, PEP, sn-PPD, and sn-PPE were all identified. In the case of TAGs that contain two HUFAs and one palmitic acid, marine mammals were rich in DPD and EPE whereas fishes were rich in sn-PDD and sn-PEE.
Two-component interactions between (perfluorooctyl) heptanol (F8H7OH) and dipalmitoylphosphatidylcholine (DPPC), which is a major component of pulmonary surfactants in mammals, were systematically elucidated using Langmuir monolayers and Langmuir-Blodgett (LB) films of the compounds. The interactions such as the miscibility of the compounds and their phase behavior were examined from thermodynamic and morphological perspectives. The surface pressure (π)–molecular area (A) and surface potential (ΔV)–A isotherms of the binary monolayers containing F8H7OH in different mole fractions (XF8H7OH) were measured simultaneously. The excess Gibbs free energy of mixing of the two components was calculated from the π–A isotherms. The resulting isotherm data were employed to construct a two-dimensional (2D) phase diagram of the system. The phase diagram revealed that the transition pressure as well as the monolayer collapse pressure change with changes in XF8H7OH. These thermodynamic analyses suggested that the miscibility of the two components and the solidification of DPPC monolayers can be induced by the addition of F8H7OH. The phase behavior upon monolayer compression was observed morphologically in situ using Brewster angle microscopy (BAM) and fluorescence microscopy (FM), as well as ex situ using atomic force microscopy (AFM). Interestingly, the AFM-based analysis revealed the formation of monodispersed 2D micelles consisting of F8H7OH at low surface pressures.
The interaction of (perfluorooctyl)nonanol (F8H9OH) with dipalmitoylphosphatidylcholine (DPPC) was systematically studied in two-component monolayers at air–water interface. The thermodynamic property and phase morphology of the monolayers were investigated by isotherm measurements and several microscopic methods such as Brewster angle microscopy, fluorescence microscopy, and atomic force microscopy (AFM). The AFM topographies for Langmuir-Blodgett films of F8H9OH exhibit the formation of monodispersed surface micelles. In the two-component system, the incorporation of F8H9OH induces condensation (or solidification) of DPPC monolayers. The excess Gibbs free energy and interaction parameter (or energy) of the two components were calculated from the isotherm data. Both the phase transition pressure for the coexistence of ordered and disordered phases and collapse pressure of monolayers vary with the mole fraction of F8H9OH, indicating binary miscibility between F8H9OH and DPPC within a monolayer state. The miscibility is also confirmed visually by in situ and ex situ microscopy at micro- and nanometer scales.
Calorimetric measurements were conducted on aqueous solutions of sodium alkyl sulfates (SCnS; H(CH2)nOSO3Na, n = 5–13) at 298.15 K. The solute partial molar enthalpy, Hs, was evaluated referred to infinitely diluted state and compared for the SCnS homologues. At low concentrations, the Hs increased with the molality m until the critical micelle concentration (CMC) was reached. In the concentration range between the CMC and about three times the CMC, the Hs decreased with increasing log m: Hs = (17.9 - 1.8 n) - 14/(n-4.6) log m. The Hs observed at the CMC was taken as the enthalpy of micelle formation, ΔHm, which was expressed as ΔHm / kJ mol–1 = 21.3 - 1.7n for SCnS with n from 7 to 13. The Gibbs energy of micelle formation, ΔGm, was estimated from the CMC values: ΔGm / kJ mol–1 = 0.2 - 3.1 n. The entropy of micelle formation, ΔSm, was calculated as TΔSm / kJ mol–1 = 21.1 + 1.4 n. The large positive entropy term was the driving force for micelle formation. An attempt was also made to calculate the concentration dependence of Hs for SDS (SC12S) from the concentrations and the apparent molar enthalpies estimated for the sodium ion, dodecyl sulfate ion, and the micelles.
To investigate the effects of dietary Grifola frondosa on cholesterol, normal mice were fed a diet containing 1% cholesterol (HC group) or 1% cholesterol and 10% freeze-dried G. frondosa powder (HC+G group) for 4 weeks and hepatic and plasma lipid levels were compared with those of a cholesterol-free diet-fed mice (N group). Hepatic total cholesterol (TC), triacylglycerol contents were considerably increased and plasma TC / phospholipid (PL) was also increased significantly in the HC group compared with the N group. However, plasma TC content decreased in the HC+G group compared with the HC group. To characterize the mechanisms responsible for lowered plasma cholesterol in G. frondosa-supplemented mice, hepatic gene expression was profiled using DNA microarray and gene ontology. Genome analyses revealed that de novo cholesterol synthesis genes were suppressed following cholesterol intake. However, expression of bile acid biosynthesis and low-density lipoprotein receptor genes showed little change. Scarb1, Abcg5, and Abcg8, involved in cholesterol transport and excretion, were slightly upregulated in the HC+G group compared with the HC group. These data indicate the plasma cholesterol-lowering effect of G. frondosa. Moreover, fatty acid (FA) β-oxidation was promoted via adipocytokine signaling pathways, and Saa, encodes serum amyloid A related to arteriosclerosis, was suppressed in the HC+G group.
Palm and soya oils were converted to monoglycerides via transesterification of triglycerides with glycerol by one step process to produce renewable polyols. Thermoplastic polyurethanes (TPPUs) were prepared from the reaction of the monoglycerides which act as polyol with 4,4′-methylenediphenyldiisocyanate (MDI) whereas, thermosetting polyurethanes (TSPUs) were prepared from the reaction of glycerol, MDI and monoglycerides in one pot. Characterization of the polyurethanes was carried out by FT-IR, 1H NMR, and iodine value and sol-gel fraction. The TSPUs showed good thermal properties compared to TPPUs as well as TSPUs exhibits good properties in pencil hardness and adhesion, however poorer in flexural and impact strength compared to TPPUs. The higher percentage of cross linked fraction, the higher degree of cross linking occurred, which is due to the higher number of double bond presents in the TSPUs. These were reflected in iodine value test as the highest iodine value of the soya-based thermosetting polyurethanes confirmed the highest degree of cross linking. Polyurethanes based on soya oil showed better properties compared to palm oil. This study is a breakthrough development of polyurethane resins using palm and soya oils as one of the raw materials.
We report shape, size, and internal cross-sectional structure of diglycerol monomyristate (C14G2) reverse micelles in n-hexadecane near the critical point using small-angle X-ray scattering (SAXS). Pair-distance distribution function, p(r), which gives structural information in real-space, was obtained by indirect Fourier transformation (IFT) method. The p(r) showed a clear picture of rodlike micelles at higher temperatures well above the critical point (micellar solution phase separates into two immiscible liquids at ~ 48°C). At a fixed surfactant concentration (5% C14G2), decrease in temperature increases the micellar size monotonously and surprisingly shape of the p(r) curve at 50°C; close to the critical point, mimics the shape of the two dimensional disk-like micelles indicating the onset of critical fluctuations (attractive interactions among rodlike micelles forming a weak network). A similar behavior has been observed with normal micelles in aqueous system near the critical point. When the system is heated to 60°C, shape of the p(r) curve regains rodlike structure. At fixed temperature of 60°C, increase in C14G2 concentration induced one dimensional micellar growth. Maximum length of micelles increases from ca. 23.5 to 46.0 nm upon increasing concentration from 1 to 12% keeping cross section diameter apparently unchanged at ca. 4.0 nm.