Rice Bran Oil contains a variety of Unsaponifiable Constituents (USC) that are presumed to contribute to the high value of Unsaponifable Matter (USM). The objectives of the present study were to identify and quantify the constituents in USM. The changes that the unsaponifiables undergo during saponification were also quantitatively investigated. While analyzing the percentage of all constituents, the percentage of sterol get increased from 22.46 to 23.77 in USM of crude rice bran oil (CRBO) and 33.42 to 36.79 in USM of refined rice bran oil (RRBO). Oryzanol that comprised 34% of the unsaponifiable in the crude oil by direct estimation was almost eliminated in USM and same in refined oil. The results also revealed the presence of four additional classes of compounds that were quantified in USM (policosanol, fatty aldehydes, triterpene alcohols and potassium salt of oryzanols). Among the four classes of compounds, policosanol contributed high percentage in USM, (43.39% in CRBO and 28.46% in RRBO). Fatty aldehydes, triterpene alcohols and potassium salt of oryzanols together contributed 27.68% and 25.13% of USM from CRBO and RRBO respectively. The HPTLC method employed here thus, accounted for 96.75% by wt of the USM of CRBO and 92.00% by wt of the USM of RRBO.

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The effectiveness of ultrasound in washing textiles was investigated using polyester woven fabrics soiled with model contaminants such as oleic acid/Sudan III mixture and carbon black. The soiled and original fabrics were washed together in aqueous solutions with shaking or frequency-modulated ultrasound. The detergency and the soil redeposition were evaluated from the change in the surface reflectance of the soiled and the original fabrics due to the washing. The results were strongly dependent on the type of mechanical action. Ultrasound removed the contaminants in a short time and at low bath ratios as compared with shaking. In addition, the ultrasound caused little damage to the fabric during washing. The detergency was much larger for the ultrasonic washing than for shake washing in aqueous solutions containing alkali, surfactants, and commercial detergent. However, uneven cleaning and soil redeposition were frequently observed during ultrasonic washing. This was the only observed limitation to this approach of textile washing.

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Natural fatty derivatives (oleochemicals) have been used as intermediate materials in several industries replacing the harmful and expensive petrochemicals. Fatty ethoxylates are one of these natural fatty derivatives. In the present work Jatropha fatty acids were derived from the non edible Jatropha oil and used as the fat source precursor. The ethoxylation process was carried out on the derived fatty acids using a conventional cheap catalyst (K₂CO₃) in order to obtain economically and naturally valuable non-ionic surfactants. Ethoxylation reaction was proceeded using ethylene oxide gas in the presence of 1 or 2% K₂CO₃ catalyst at 120 and 145°C for 5, 8 and 12 hours. The prepared products were evaluated for their chemical and physical properties as well as its application as non- ionic fat-liquoring agents in leather industry. The obtained results showed that the number of ethylene oxide groups introduced in the fatty acids as well as their EO% increased as the temperature and time of the reaction increased. The highest ethoxylation number was obtained at 145°C for 8 hr. Also, the prepared ethoxylated products were found to be effective fat-liquors with high HLB values giving stable oil in water emulsions. The fat-liquored leather led to an improvement in its mechanical properties such as tensile strength and elongation at break. In addition, a significant enhancement in the texture of the treated leather by the prepared fat-liquors as indicated from the scanning electron microscope (SEM) images was observed.

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New liquid substances that induce the formation of lecithin organogels composed of reverse worm-like micelles were studied. The phase behavior and rheological properties of lecithin/polyglycerol (PGL)/oil systems were investigated in detail; the polymerization degrees of the glycerol residues were 3, 4, 6, 10, 20, and 40. From the partial phase diagrams of the lecithin/PGL/n-decane systems, it was apparent that highly viscoelastic reverse worm-like micelles formed upon the addition of small amounts of the PGL, except in the case of the PGL with a polymerization degree of 40. Steady-flow viscosity measurements showed that the zero-shear viscosity (η₀) of the reverse worm-like micelles rapidly increased with the concentration and polymerization degree of the PGLs, reaching a maximum value that was 750,000 times the viscosity of n-decane and thus resulting in the growth of these micelles. It is noteworthy that the η₀ values of lecithin organogels formed using PGLs were higher than the η₀ value of the lecithin organogel formed using glycerol (GL). From dynamic viscoelasticity measurements, it was shown that the viscoelastic behavior of the reverse worm-like micelles was consistent with the single Maxwell model, which is the basic model of a viscoelastic body. It follows from this study that PGLs are useful liquids because they can induce the formation of lecithin organogels with high viscoelasticity, as do other liquids such as water, glycerol, ethylene glycol, and formamide.

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In this paper, we discuss a useful technique to fabricate patterned single layers consisting of quantum dots on two-dimensional templates fabricated from phase-separated mixed Langmuir-Blodgett (LB) films. The phase-separated structures are governed by two competing interactions-line tension and dipole-dipole interaction-and are tunable by adjusting the intermolecular interactions between the film-forming molecules and the fabrication conditions. The templates can be fabricated from mixed LB films containing silane-coupling agents, which form covalent bonds with Si wafers. The CdS- or CdSe/ZnS-nanoparticles were immobilized on the templates using a chemisorption technique. The samples were analyzed using ultraviolet-visible absorption spectroscopy, emission spectroscopy, atomic force microscopy, scanning electron microscopy, and fluorescence microscopy. The diameters of the CdS-NPs and CdSe/ZnS were estimated to be about 2.6 and 4.5 nm, respectively, using the Brus equation. We successfully obtained a patterned single layer consisting of quantum dots on the templates. The density of the immobilized-CdSe/ZnS-NPs on these templates can be controlled through variations in the concentration of the aqueous dispersion of CdSe/ZnS-NPs. Fluorescence observations indicate that the immobilized-CdSe/ZnS-NPs on the templates serve as light-emitting devices. These results indicate that patterned quantum dots can be formed only through self-assembly processes.

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Mannosylerythritol lipids (MELs) are secreted by yeasts and are promising glycolipid biosurfactants. In our study on the non-aqueous phase behaviors of MEL homologues, we found that MEL-D (4-O-[2’,3’-di-O-alka(e)noyl-β-D-mannopyranosyl]-(2R,3S)-erythritol) forms aggregates in decane. The microscopic observation and the X-ray scattering measurement of these aggregates revealed that they are reverse vesicles that consist of bilayers whose hydrophilic domains are located in the interior of the bilayers. In addition, MEL-D formed reverse vesicles without co-surfactants and co-solvents in various oily solutions, such as n-alkanes, cyclohexane, squalane, squalene, and silicone oils at a concentration below 10 mM. This is the first report on the reverse vesicle formation from biosurfactants.

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The essential oil in traditional Chinese medicine (TCM) Herba Artemisiae Scopariae (HAC) grown in China was obtained by hydrodistillation and studied by GC and GC-MS. Twenty compounds were identified representing 96.6% of the essential oil, of which the most prominent were n-hexadecanoic acid (33.1%), caryophyllene oxide (19.1%) and spathulenol (9.9%). The antioxidant activity of the essential oil (25-400 μg/ml) of HAC was evaluated by 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity and ferric reducing/antioxidant power (FRAP) assay. The essential oil of HAC exhibited a strong antioxidant activity, which possess a good potential for use in the food and pharmaceutical industry.

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Optimization of the enzymatic synthesis of palm fatty hydrazide by the response surface methodology (RSM) was conducted using the Design-Expert 6 software. The palm fatty hydrazide was synthesized from refined, bleached and deodorized palm olein (RBDPOo) and neutralized hydrazine monohydrate in the presence of Rhizomucor miehei lipase, Lipozyme RMIM, an immobilized lipase in n-hexane. The reaction conditions such as the percentage of enzyme, reaction temperature, stirring speed and reaction time were selected as independent variables or studied factors, while the amount of crude palm fatty hydrazide obtained was selected as a dependent variable or response. The study was conducted using a central composite design (CCD) at five coded levels and the experimental data were analyzed using a quadratic model. The analysis of variance (ANOVA) indicates that the model was significant at 95% confidence level with Prob>F of 0.0033, where the regression coefficient value, R² was 0.8415 and lack-of-fit of 0.0984. A percentage of enzyme of 6%, a reaction temperature of 40°C, a stirring speed of 350 rpm and a reaction time of 18 h were found to be the optimum conditions for the conversion of RBDPOo into palm fatty hydrazide.

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