Avocado fruit is rich in monounsaturated fat and contains relatively high level of important lipid-soluble compounds such as vitamin E, β-sitosterol and carotenoids. The consumption of avocado fruit is highly related to its potential benefits. However, with the increase of avocado production, short time of maturation and easy oxidation of avocado fruit are the main problem for producers. The production of oil from avocado fruit, thus, is highly promoted. This paper discusses the effects of different extraction methods on chemical composition and yield of oils from avocado fruits.
In this study, the effect of cultivar, harvest year (2010 and 2011) and the geographic regions (Mediterranean, Aegean, Southeastern Anatolia, Marmara and Black Sea) on fatty acid compositions of olive oil was investigated. The proportions of palmitic acid and linoleic acid, which comprised most of the amount of fatty acids after oleic acid, showed variations according to the region and cultivar. The amount of linoleic acid was found higher in some cultivars than that of palmitic acid. In the Aegean, Marmara and Mediterranean Regions, no significant difference was observed between olive cultivars for oleic and linoleic acids. The highest linoleic and lowest oleic acid content were determined in the Black Sea Region. One cultivar (Butko) showed an oleic acid proportion below 55% in this region. The effect of the harvest year on the fatty acid composition of the samples was also found significant. In oils harvested in the second year, a decrease in the amount of linoleic acid was observed, while the amount of oleic acid increased. The highest oleic acid proportion was found in olive oils produced from harvests in the Aegean and Mediterranean regions.
Palm fatty acid distillate (PFAD) is cheap and valuable byproduct of edible oil processing industries. This study was designed to characterize PFAD collected from different local oil industries. AOCS methods were used for the determination of physicochemical parameters such as free fatty acid (FFA), saponification value (SV), iodine value (IV), peroxide value (PV) and moisture content. Fatty acid composition was analyzed using GC-MS. Moisture content of samples was found to be in the range between 0.06-7.50%, while FFA, SV, IV and PV were found to be 65.70-94.68%, 195.23-219.64 mg KOH/g, 38.49- 63.10 g I2/100 g, 1.09-16.50 meq/kg, respectively. Mean value of fatty acids in PFAD was found as 0.04% lauric, 0.42% myristic, 41.25% palmitic, 7.29% stearic, 41.58% oleic, 8.95 % linoleic, 0.04% eicosenoic, 0.27% arachidic, 0.07% docosanoic, and 0.05% tetracosanoic acid, respectively. Palmitic acid was found as dominant saturated fatty acid 38.63-45.30%, whereas oleic acid C18:1 n9 was major unsaturated fatty acid 33.54-44.05 % in PFAD.
In order to elucidate an electroacoustic phenomenon of mixed micelles in an aqueous solution, we measured the colloid vibration current (CVI) in aqueous solutions of binary surfactant mixtures. Based on the thermodynamic treatment of critical micelle concentration (cmc) values determined by conductivity measurements, it was expected that dodecyltrimethylammonium bromide (DTAB) and dodecyltrimethylammonium chloride (DTAC) molecules would mix ideally in the micelle. However, the micelle composition as evaluated from the CVI measurement, based on the linear dependence of the CVI value on the micelle composition, differed from the aforementioned ideality. Considering these observations, we concluded that the CVI measurement was more sensitive to the counterion distribution near the micelle surface, whereas the thermodynamically determined micelle composition included the counterions more loosely bound in the diffuse double layer due to the electroneutrality condition included in its assumption. On the other hand, the phase diagram illustrating micelle formation in the lithium dodecyl sulfate (LiDS) – lithium perfluorooctane sulfonate (LiFOS) mixture system showed a heteroazeotropic point arising from the stronger interactions between homologous surfactants than between heterologous ones. Although the concentration dependence of CVI values was expected to drastically change at a heteroazeotropic point due to the enormous variation in the density of the micelle core, the results showed a monotonous change, which suggests that the density of the micelle core varies continuously. By taking the partial molar volume of fluorocarbon compounds in the hydrocarbon compounds into account, the density of the micelle core was affected by the size of the micelle as well as its constituents.
In the present study, mechanical phenomena on fractal agar gel were analyzed to understand the interfacial properties of hydrophilic biosurfaces. The evaluation of adhesion strength between the fractal agar gel surfaces showed that the fractal structure inhibits the adhesion between the agar gel surfaces. In addition, when the disintegration behavior of an agar gel block was observed between fractal agar gel substrates, the rough structure prevented the sliding of an agar gel block. These findings are useful for understanding the biological significance of rough structure on the biological surfaces.
A two-step enzymatic transesterification process in a solvent-free system has been developed as a novel approach to the production of biodiesel using acid oil from rice bran oil soapstock. The acid oil consisted of 53.7 wt% fatty acids, 2.4 wt% monoacylglycerols, 9.1 wt% diacylglycerols, 28.8 wt% triacylglycerols, and 6.0 wt% others. Three immobilized lipases were evaluated as potential biocatalysts, including Novozym 435 from Candida antarctica, Lipozyme RM IM from Rhizomucor miehei, and Lipozyme TL IM from Thermomyces lanuginosus. The effects of molar ratio of acid oil to ethanol, temperature, and enzyme loading were investigated to determine the optimum conditions for the transesterification with the three immobilized lipases. The optimum conditions of the three immobilized lipases were a molar ratio of 1:5 (acid oil to ethanol), the temperature range of 30-40°C, and the enzyme loading range of 5-10%. The two-step transesterification was then conducted under the optimum conditions of each lipase. The stepwise use of Novozym 435 and Lipozyme TL IM or Lipozyme RM IM and Lipozyme TL IM resulted in similar or higher levels of yield to the individual lipases. The maximum yields obtained in both stepwise uses were ca. 92%.
Crude soybean and rapeseed oils were subjected to the method to determine FA distributions in TAG using Candida antarctica lipase B, giving similar results to those for refined oils. Minor components in crude oils, such as percentages of FFA or phospholipids were indicated not to affect 1(3)-selective transesterification by the lipase and FA compositional analysis of the resulting 2-MAG fraction significantly. Phospholipids were confirmed not to contaminate the 2-MAG fraction. Oxidized soybean oil with a PV of 10 meq/kg also gave similar results to the ones for refined oil. The method was confirmed to be applicable for crude oils and oxidized oils with a PV smaller than 10 meq/kg without prior purification of TAG.
Synthesis of chromenopyrimidine derivatives and the related fused system carried out by the reaction of chromene derivative 1 with various reagents under suitable reaction conditions. Condensation of stearoyl chloride with these heterocycles, then, propoxylated the products using propylene oxide to produce surface active agents having a twofold capacity as surface and antimicrobial dynamic specialists which may be served in the production of medications, pesticides, beautifying agents or may be utilized as an antimicrobial. Some of the surface properties and antimicrobial activity were resolved.
In this study, we prepared virgin (S, L) and calcined (S-380, S-1000, L-380, L-1000) magnesium hydroxide for regeneration of waste edible oil. Deterioration of soybean oil, rapeseed oil, and olive oil was achieved by heat and aeration treatment. The properties of the different adsorbents were investigated using specific surface area measurements, scanning electron microscopy, X-ray diffraction analysis, thermogravimetric-differential thermal analysis, and surface pH measurement. Moreover, the relationship between the changes in acid value (AV) and carbonyl value (CV) and the adsorbent properties were evaluated. The specific surface areas of S-380 and L-380 were greater than that of other adsorbents. In addition, the XRD results show that S-380 and L-380 contain both magnesium hydroxide and magnesium oxide structures. The decreases in AV and CV using S-380 and L-380 were greater than achieved using other adsorbents. The correlation coefficients between the decrease in AV and CV and specific surface area were 0.947 for soybean oil, 0.649 for rapeseed oil, and 0.773 for olive oil, respectively. The results obtained in this study suggest that a physical property of the adsorbent, namely specific surface area, was primarily responsible for the observed decreases in AV and CV. Overall, the results suggest that S-380 and L-380 are useful for the regeneration of waste edible oil.
Conjugated linoleic acid (CLA) has several beneficial biological properties. Specifically, trans10, cis12-CLA, one of the CLA isomers, has strong physiologic activity against cancer and obesity. However, compared with cis9, trans11-CLA, a naturally occurring CLA isomer, trans10, cis12-CLA tends to be easily metabolized. Therefore, to make efficient use of its biological properties, it is necessary to overcome the rapid clearance of trans10, cis12-CLA from the blood. Here, we employed premix membrane emulsification to prepare two oil-in-water CLA microemulsions (CLA-ME), 100 nm CLA-ME and 200 nm CLA-ME, and investigated their pharmacokinetics in a mouse model. We report that 100 nm CLA-ME contributed to the concentration of blood CLA for longer than 200 nm CLA-ME, indicating that small CLA microparticles were more suitable for maintaining blood trans10, cis12-CLA levels in vivo. However, both CLA-ME could be hardly detected in blood and other tissues 24 h after administration, suggesting that additional strategies for prolonging CLA-ME half-life are required.