The impact of microwave roasting on the thermooxidative degradation of perah seed oil (PSO) was evaluated during heating at a frying temperature (170°C). The roasting resulted significantly lower increment of the values of oxidative indices such as free acidity, peroxide value, p-anisidine, total oxidation (TOTOX), specific extinctions and thiobarbituric acid in oils during heating. The colour L* (lightness) value dropped gradually as the heating time increased up to 12 h, whereas a*(redness) and b* (yellowness) tended to increase. The viscosity and total polar compound in roasted PSO was lower as compared to that in unroasted one at each heating times. The tocol retention was also high in roasted samples throughout the heating period. The relative contents of polyunsaturated fatty acids (PUFAs) were decreased to 94.42% and saturated fatty acids (SFAs) were increased to 110.20% in unroasted sample, after 12 h of heating. On the other hand, in 3 min roasted samples, the relative contents of PUFAs were decreased to 98.08% and of SFAs were increased to 103.41% after 12 h of heating. Outcome from analyses showed that microwave roasting reduced the oxidative deteriorations of PSO during heating.
The aim of this study was to discriminate the authenticity of perilla oils distributed in Korea using their 1H nuclear magnetic resonance (NMR) spectra acquired by a 43 MHz low-field benchtop NMR spectrometer. Significant differences existed in the integration values of all 6 peaks found in the spectrum between authentic and adulterated perilla oil samples. The integration values of 4 peaks that signify the methylene protons present in all fatty acids (FA) and allylic or olefinic protons present in all unsaturated FA were the best variables for establishing perilla oil authenticity. The procedure for applying the range of variables found in authentic perilla oil samples correctly discriminated between the samples of perilla oils with soybean oils added at concentrations of ≥ 6 vol%. The results demonstrated that this NMR procedure is a possible cost-effective alternative to the high-field 1H NMR method for discriminating the authenticity of perilla oils.
Fish oil rich in docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) is known to have an unpleasant smell, even at low oxidation levels. Therefore, it is highly important to know the major volatiles formed during the early stages of fish oil oxidation. Comparative study with solid-phase microextraction (SPME) and static headspace (SHS) methods showed that 2-propenal (acrolein) was formed as the major volatile from the beginning of fish oil triacylglycerol (TAG) oxidation. The effectiveness of SPME extraction on each volatile was different from each fiber. Among the three different SPME fibers used in the present study, carboxen/polydimethylsiloxane (CAR/PDMS) was determined to be a better fiber for measuring the volatiles, including acrolein. The present study also showed that the non-selective SHS method is useful for determining the characteristic volatile formation in the early stages of fish oil TAG oxidation.
Olive trees are one of the most important oil crops in the world due to the sensorial and nutritional characteristics of olive oil, such as lipid composition and antioxidant content, and the medicinal properties of its leaves. In this paper, callus formation was induced using nodal segments of olive tree (Olea europaea cv. cornicabra) as explants. Fatty acid profile, total phenolic compounds and total flavonoid compounds were determined in callus culture after 15 weeks and compared with leaf and nodal segments tissues. There was no statistical difference in phenolic compounds among leaf, nodal segments and callus culture, whereas flavonoid compounds were higher in leaf. Fatty acid profile was similar in leaf, nodal segments and callus culture and was constituted by hexadecanoic acid, octadecanoic acid, cis-9-octadecenoic acid, cis-9,12-octadecadienoic acid, cis-9,12,15-octadecatrienoic acid. Hexadecanoic acid was the main fatty acid in callus, leaf and nodal segments with 35.0, 39.0 and 40.0% (w/w), of the lipid composition, respectively. With this paper, it is being reported for the first time the capacity of callus culture to accumulate fatty acids. Our results could serve to continue studying the production of fatty acids in callus cultivation as a biotechnological tool to improve different olive cultivars.
Amphiphilic random copolymers, poly(oxyethylene)/poly(oxypropylene) butyl ethers (C4EmPn), have been used as raw materials for cosmetics. This paper reports on the influence of amphiphilic random copolymers on mixtures of n-decane, water, and a nonionic surfactant, hexa(oxyethylene) dodecyl ether (C12E6). Bicontinuous phases are formed from decane/water/C12E6 mixtures at high C12E6 weight fractions (> 70 wt%). Adding C4EmPn to decane/water/C12E6 mixtures brings about the formation of bicontinuous phases and a decrease in the amount of the surfactant required for their formation, indicating efficiency boosting. The bicontinuous phase formation region in the phase diagram of the decane/water/C12E6+C4E5P5 system is largest at a specific C4E5P5 weight fraction in the C12E6/C4E5P5 mixture. When a hydrophobic polymer, in which the poly(ethylene oxide) group in C4EmPn is absent, is added to decane/water/C12E6 mixtures, no efficiency boosting is observed. These results suggest that the adjustment of the hydrophilicity-hydrophobicity balance of C12E6/C4EmPn mixture causes the efficiency boosting.
D,L-Methionine was chosen as a starting material for the preparation of a new gelator N-10-undecenoyl-D,L-methionylaminooctadecane (DL-Met-R18). Three oligo (dimethylsiloxane)-containing gelators, DL-Met-R18/Si3, DL-Met-R18/Si7-8, and DL-Met-R18/Si14-15, were also prepared from DL-Met-R18 by hydrosilylation reactions. Their gelation abilities were evaluated on the basis of the minimum gel concentration using nine solvents. Compound DL-Met-R18 was able to gelate liquid paraffin and silicone oil, but it crystallized in most solvents. However, DL-Met-R18/Si7-8 resulted to be the best gelator, gelling eight solvents at low concentrations. The results of gelation tests demonstrated that the ability to form stable gels decreases in the following order: DL-Met-R18/Si7-8 ≈ DL-Met-R18/Si14-15 > DL-Met-R18/Si3 >> DL-Met-R18. The aspects and thermal stabilities of the gels were investigated using three-component mixtures of solvents composed of hexadecyl 2-ethylhexanoate, liquid paraffin, and decamethylcyclopentasiloxane (66 combinations). DL-Met-R18/Si3, DL-Met-R18/Si7-8, and DL-Met-R18/Si14-15 could form gels with all these mixed solvent combinations; particularly, DL-Met-R18/Si7-8 gave rise to transparent or translucent gels. FT-IR spectra suggested that the formation of hydrogen bonds between the NH and C=O groups of the amides is one of driving forces involved in the gelation process. Aggregates comprising three-dimensional networks were studied by transmission electron microscopy. Moreover, the viscoelastic behavior of the gels was investigated by rheology measurements.
The synthesis of water-soluble heterocyclic compounds was verified on the basis of nonionic surfactants for use as surface-active agents. Surface characteristics such as surface and interfacial tensions, cloud point, wetting time, emulsion stability, foaming height and foaming stability were measured for these surface factors in aqueous solutions. In addition, the critical micelle concentration (CMC), the surface pressure at CMC (πcmc), the effectiveness of surface tension reduction (pC20), the maximum surface concentration (Γma.) and the minimum area/molecule at the aqueous solution/air interface (Amin) were calculated. Moreover, the biodegradability for these nonionic surfactants has been investigated. Furthermore, the antimicrobial evaluation has been evaluated with some surfactants that have demonstrated a potent cytotoxicity as antibacterial, antifungal and anticancer. These surfactants have a good water solubility, low toxicity, environmentally friendly environment, high foam, good emulsifier and easy production that will be used them in various fields such as medical drugs, insecticides, detergents, emulsifiers, cosmetics, inks clothing, leather industry and oil recovery.
The marine eukaryotic microheterotroph thraustochytrid genus Aurantiochytrium is a known producer of polyunsaturated fatty acids, carotenoids, and squalene. We previously constructed a lipid fermentation system for Aurantiochytrium sp. strains using underutilized biomass, such as canned syrup and brown macroalgae. To improve the productivity, in this study, Aurantiochytrium sp. RH-7A and RH-7A-7 that produced high levels of carotenoids, such as astaxanthin and canthaxanthin, were isolated through chemical mutagenesis. Moreover, metabolomic analysis of the strain RH-7A revealed that oxidative stress impacts carotenoid accumulation. Accordingly, the addition of ferrous ion (Fe2+), as an oxidative stress compound, to the culture medium significantly enhanced the production of astaxanthin by the mutants. These approaches improved the productivity of astaxanthin up to 9.5 mg/L/day at the flask scale using not only glucose but also fructose which is the main carbon source in fermentation systems with syrup and brown algae as the raw materials.
Mesoporous Ti–Mo bi-metal oxides with various titanium–molybdenum ratios were successfully fabricated via a facile approach by using stearic acid as a low-cost template agent. thermal gravity (TG) /differential scanning calorimetry (DSC) analysis, X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, nitrogen adsorption-desorption isotherm, NH3 temperature-programmed desorption (NH3-TPD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) measurements indicated these materials possessing mesoporous structure, sufficient pore size and high acid intensity. The catalytic performance of prepared catalysts was evaluated by esterification of free fatty acids in Jatropha curcas crude oil (JCCO) with methanol. The effects of various parameters on FFA conversion were investigated. The esterification conversion of 87.8% was achieved under the condition of 180°C, 2 h, methanol to JCCO molar ratio of 20:1 and 3.0 wt.% catalyst (relative to the weight of JCCO). The mesoporous catalysts were found to exhibit high activities toward the simultaneous esterification and transesterification of JCCO. Furthermore, the catalyst could be recovered with a good reusability.
Abdominal aortic aneurysm (AAA) is a vascular disease that results in rupture of the abdominal aorta. The risk factors for the development of AAA include smoking, male sex, hypertension, and age. AAA has a high mortality rate, but therapy for AAA is restricted to surgery in cases of large aneurysms. Clarifying the effect of dietary food on the development of AAA would be helpful for patients with AAAs. However, the relationship between dietary habits and the development of AAA is largely unknown. In our previous study, we demonstrated that adipocytes in vascular wall can induce the rupture of AAA. Therefore, we focused on the diet-induced abnormal triglyceride metabolism, which has the potential to drive AAA development. In this study, we have evaluated the effects of a high-sucrose diet on the development of AAA in a vascular hypoperfusion-induced animal model. A high sucrose diet induced high serum TG level and fatty liver. However, the AAA rupture risk and the AAA diameter were not significantly different between the control and high-sucrose groups. The intergroup differences in the elastin degradation score and collagen-positive area were insignificant. Moreover, matrix metalloproteinases, macrophages, and monocyte chemoattractant protein-1-positive areas did not differ significantly between groups. These results suggest that a high-sucrose diet does not affect the appearance of vascular adipocyte and AAA development under the vascular hypoperfusion condition.
In our previous study, the health benefits of the 1975 Japanese diet were shown to be the highest, since the diet suppressed visceral and liver fat accumulation, and hyperglycemia. In addition, the 1975 Japanese diet promoted maintenance of learning memory ability and a lengthened life span. However, the effect of the 1975 Japanese diet has not been ascertained in humans. In the current study, a diet with the characteristics of the 1975 Japanese diet was prepared to examine if this diet is beneficial for human health. The purpose of this randomized controlled trial was to determine effects of the 1975 Japanese diet (JD) in comparison with a modern Japanese diet (MD). Subjects aged 20~29 years old were randomly assigned to the MD (n=16) and JD (n=16) groups. Each subject consumed the diet three times a day for 28 days. Changes in physical conditions, including body composition and blood biochemistry, from before to after the study period were evaluated. As a result, body weight (p < 0.05), body fat percentage (p < 0.05), body fat mass (p < 0.05), serum triglyceride level (p < 0.05), and serum low-density lipoprotein cholesterol level (p < 0.05) were significantly decreased and serum high-density lipoprotein cholesterol (p < 0.05) and serum magnesium levels (p < 0.05) were significantly increased in JD group. These results showed that a diet with the characteristics of the 1975 Japanese diet has a beneficial effect on lipid metabolic parameters.
Carbonated methyl soyates have been successfully prepared by cycloaddition of carbon dioxide (CO2) to epoxidized methyl soyates in tetrabutylammonium bromide (TBAB)-based deep eutectic solvents (DES). Experimental parameters, i.e., reaction temperature, reaction time, CO2 pressure and TBAB concentration were evaluated. The different reaction conditions have a significant influence on the yields of carbonated methyl soyates. The use of TBAB-based DES (tetrabutylammonium bromide/triethylene glycol) significantly shortened the reaction time of the cycloaddition of CO2 to epoxidized methyl soyates. FT-IR and NMR analysis indicated that 95% of the yield of the five-membered cyclic carbonated methyl soyates were obtained at 120°C with 1.0 MPa pressure of CO2.
Candlenut oil (CNO) is a potentially new feedstock for biodiesel (BDF) production. In this paper, a two-step co-solvent method for BDF production from CNO was examined. Firstly, esterification of free fatty acids (FFAs) (7 wt%) present in CNO was carried out using a co-solvent of acetonitrile (30 wt%) and H2SO4 as a catalyst. The content of FFAs was reduced to 0.8 wt% in 1 h at 65°C. Subsequent transesterification of the crude oil produced was carried out using a co-solvent of acetone (20 wt%) and 1 wt% potassium hydroxide (KOH). Ester content of 99.3% was obtained at 40°C in 45 min. The water content in BDF was 0.023% upon purification using vacuum distillation at 5 kPa. The components of CNO BDF were characterized using a Fourier-transform infrared spectrometry and gas chromatography-flame ionization detector. The physicochemical properties of BDF satisfied the ASTM D6751-02 standard. The gaseous exhaust emissions from the diesel engine upon combustion of the BDF blends (B0–B100) with petrodiesel were examined. The emissions of carbon monoxide and hydrocarbons were clearly lower, but that of nitrogen oxides was higher in comparison to those from petro-diesel.
Cryogenic treatment, like the freeze–thaw process, has been reported to be effective in modifying the physicochemical properties of polymeric hydrogels. However, not much attention has been paid to this process in terms of the precipitation of surfactant–water systems. In this study, two effective cryogenic methodologies were successfully reported to alter the physicochemical properties of a precipitate of an octyl β-D-galactoside (Oct-Gal)–water system. First, hyperrapid cooling (i.e., cooling at 30°C/min) was found to be an effective type of cryogenic treatment: the phase transition temperature (TK) and enthalpy at the phase transition (∆HK) between the crystal-dispersed phase and the sol (micelle) phase significantly decreased. In addition, cryogenic treatment in the presence of electrolytes, such as NaCl, NaBr, and CsCl, was effective even in the absence of the hyperrapid cooling condition. The hyperrapid cooling or the addition of certain electrolytes was considered to prevent the precipitation of the Oct-Gal hemihydrate crystals prior to the complete freezing of ice and the electrolyte/ice eutectic. Hence, the size of the aggregated crystals prepared by the above-mentioned effective cryogenic treatments seemed to be decreased compared with that of the normal precipitated crystals, thereby changing TK and ∆HK. Thus, two basic methodologies for the modification of the physicochemical properties of the crystal-dispersed phase of surfactant–water systems are discussed.