The present work has been carried out to ascertain the influence of different processing systems employed in olive process on the chemical composition, quality and stability of three Chemlali olive oils. Among these oils, two were classified as extra-virgin olive oils and the third named repassed olive oil was classified as an ordinary virgin olive oil. The analysis of the effect of the processing (two- and three-phases) on the analytical determinations values, revealed statistically significant differences (p<0.05) in some parameters, mainly in oxidative stability, antioxidant activity, total waxes, total phenols, o-diphenols and α-tocopherol contents as well as phenolic composition. The phenolic composition values were higher in the extra-virgin olive oil obtained from the two-phase system than in that obtained from the three-phase processing because it does not require the addition of water to the olive paste. Nevertheless, they were lower in the ordinary virgin olive oil (repassed olive oil) which was obtained by introducing hot water to the wet residues into the centrifugation processing at two-phases, than those in the extra-virgin olive oils obtained from the two- and three-phase processing.

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Seed fat of Madhuca longifolia known as mee fat (MF) has been considered as a potential plant fat for producing fat mixture to simulate the properties of lard. A study was carried out to evaluate the effect of addition of palm stearin (PS) on the solidification behavior of MF to formulate a mixture to become similar in solidification characteristics of lard. Three fat mixtures were prepared by blending MF with palm stearin PS in different ratios: MF:PS (99.5:0.5), MF:PS (99:1), MF:PS (98:2) (w/w), and identified by the mass ratio of MF to PS. The fat mixtures were compared with lard in terms of their fatty acid and triacylglycerol compositions, differential scanning calorimetric (DSC) thermal profiles and solid fat content (SFC) characteristics. Results showed that there were considerable differences between lard and MF:PS fat mixtures with regard to fatty acid and triacylglycerol compositions. The increasing proportion of PS in MF:PS fat mixtures caused a general increase in SFC at different temperatures with respect to the SFC profile of native MF. Of the three binary mixtures, MF:PS (99:1) was found to show the least difference to lard in terms of SFC values throughout the temperature range.

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We examined the promotional effects of additives on fat crystallization, such as inorganic (talc, carbon nanotube (CNT), and graphite) and organic (theobromine, ellagic acid dihydrate (EAD), and terephthalic acid) materials. The triacylglycerols (TAGs) of trilauroylglycerol (LLL), trimyristoylglycerol (MMM), and tripalmitoylglycerol (PPP) were employed as the fats. The additives (1 wt%) were added to the molten TAGs, and then the mixtures were cooled at a rate of 1°C/min followed by heating at a rate of 5°C/min. The crystallization and melting properties were observed using differential scanning calorimetry, X-ray diffraction, and polarized optical microscope (POM). Consequently, we found that the above six additives remarkably increased the initial temperatures of crystallization (T_i) on cooling without changing the melting temperatures. For example, in the case of LLL, the increases in T_i were 2.6°C (talc), 3.9°C (CNT), 8.1°C (graphite), 1.1°C (theobromine), 2.0°C (EAD), and 6.8°C (terephthalic acid). Very similar effects were observed for the crystallization of MMM and PPP with the six additives. Furthermore, the polymorphs of the first occurring crystals were changed from metastable to more stable forms by many of these additives. The POM observation revealed that the crystallization was initiated at the surfaces of additive particles. This study has shown for the first time that the heterogeneous nucleation of fat crystals can be greatly promoted by new types of additives. Such additives have great potential to promote fat crystallization by not only hydrophobic but also hydrophilic molecular interactions between the fats and additives.

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The aim of present study was to develop and evaluate nanoemulsion formulations of clove essential oil (CEO) for its antibacterial effects in comparison with pure CEO and standard amikacin antibiotic (positive control). Different nanoemulsions of CEO were developed by aqueous phase titration method via construction of pseudo-ternary phase diagrams and investigated for thermodynamic stability and self-nanoemulsification tests. Selected formulations (F1-F5) were characterized for droplet size distribution, viscosity, zeta potential, transmittance and surface morphology. Based on lowest droplet size (29.1 nm), lowest PI (0.026), lowest viscosity (34.6 cp), optimal zeta potential (-31.4 mV), highest transmittance (99.4 %) and lowest concentration of Triacetin (8 % w/w), CEO nanoemulsion F1 (containing 1 % w/w of CEO, 8 % w/w of Triacetin, 15 % w/w of Tween-80, 15 % w/w of Labrasol and 61 % w/w of water) was subjected to antibacterial studies in comparison with pure oil and standard amikacin. The antibacterial effects of F1 were found to be superior over pure oil against all bacterial strains investigated. However, the antibacterial effects of F1 were highly comparable with standard amikacin against all bacterial strains. The minimum inhibitory concentrations (MICs) of F1 were observed in the range of 0.075-0.300 % w/w as compared to pure oil (MICs 0.130-0.500 % w/w) and standard amikacin (MICs 2-16 μg/ml). These results indicated the potential of nanoemulsions for enhancing the therapeutic efficacy of natural bioactive ingredients such as CEO.

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The adsorption of dimethylsilicone (DMS) from its emulsion onto hair-surface models was investigated. The model surfaces were prepared on silicon wafers by utilizing a micro-phase separation in mixed Langmuir monolayers with a chemically adsorptive organosilane, n-octadecyltriethoxysilane (ODTES), as one component. The resulting surfaces consisted of hydrophobic micro-domains of polymerized ODTES and a surrounding hydrophilic surface silanol (SiOH) region of the silicon wafer, corresponding to the healthy and damaged regions of the hair surface, respectively, in terms of surface wettability. DMS preferentially adsorbed onto the high surface energy hydrophilic region of the model surface when the hydrophobic micro-domains were composed of fully condensed alkyl chains. The surface energy of the micro-domains could be controlled by using palmitic acid (PA) as the second component to form the micro-domains in the phase-separated Langmuir monolayers. The increase in the surface energy of the micro-domains induced the adsorption of DMS onto the intrinsically hydrophobic domain surface.

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Fatty acids, fatty acid potassium soaps, glycerol and water are essential ingredients in the production of stable cream soaps. In this study, the behavior of these components in solution was investigated to elucidate the stability conditions and mechanism of cream soaps. It was determined that the cream soaps were a dispersion of 1:1 acid soap (1:1 molar ratio of potassium soap/fatty acid) crystals in the lamellar gel phase, which has confirmed from the phase behavior diagrams and small angle X-ray scattering data. Glycerol was crucial ingredient in the formation of the lamellar gel phase. The cleansing process of the cream soaps was also evaluated using the same diagrams. The structure of the continuous phase in cream soaps changed from lamellar gel to a micellar aqueous solution upon the addition of water. This structural change during the washing process is important in producing the foaming activity of acid soaps to wash away dirt or excess fats from the skin surface.

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This study sought to investigate the effects of essential oil from lemon (Citrus limoni) peels on acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) activities in vitro. The essential oil was extracted by hydrodistillation, dried with anhydrous Na₂SO₄ and characterized using gas chromatography. Antioxidant properties of the oil and inhibition of pro-oxidant-induced lipid peroxidation in rats brain homogenate were also assessed. The essential oil inhibited AChE and BChE activities in a concentration-dependent manner. GC analysis revealed the presence of sabinene, limonene, α-pinene, β-pinene, neral, geranial, 1,8-cineole, linalool, borneol, α-terpineol, terpinen-4-ol, linalyl acetate and β-caryophyllene. Furthermore, the essential oil exhibited antioxidant activities as typified by ferric reducing property, Fe²⁺-chelation and radicals [DPPH, ABTS, OH, NO] scavenging abilities. The inhibition of AChE and BChE activities, inhibition of pro-oxidant induced lipid peroxidation and antioxidant activities could be possible mechanisms for the use of the essential oil in the management and prevention of oxidative stress-induced neurodegeneration.

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An ionic liquid (IL) system for the enzymatic epoxidation of soybean oil was studied. The effects of active oxygen carriers (different fatty acids) and ILs ([Bmim]PF₆ and [Bmim]BF₄) on the enzymatic epoxidation were investigated. Response surface methodology (RSM) was used to study and optimize the effects of variables (reaction time, reaction temperature, molar ratio of H₂O₂/C=C-bonds, and molar ratio of fatty acid/C=C-bonds) on the epoxy oxygen group content (EOC) of epoxidized soybean oil (ESO). Results showed that the enzymatic epoxidation of soybean oil can be enhanced using tetradecanoic acid (C₁₃H₂₇COOH) as active oxygen carrier and [Bmim]PF₆ as reaction medium. The optimum EOC of ESO was 5.9 ± 0.3% under the following conditions: reaction temperature 46°C, reaction time 11 h, enzyme load 3% (w/w, relative to the weight of soybean oil), molar ratio of H₂O₂/C=C-bonds 1.8:1, and molar ratio of C₁₃H₂₇COOH/C=C-bonds 0.5:1.

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Plant growth-promoting fungi (PGPF) have the potential to confer several benefits to plants in terms of growth and protection against pests and pathogens. In the present study, we tested whether a PGPF isolate, Penicillium spp. GP15-1 (derived from zoysiagrass rhizospheres), stimulates growth and disease resistance in the cucumber plant. The use of the barley grain inoculum GP15-1 significantly enhanced root and shoot growth and biomass of cucumber plants. A root colonization study revealed that GP15-1 was a very rapid and efficient root colonizer and was isolated in significantly higher frequencies from the upper root parts than from the middle and lower root parts during the first 14 d of seedling growth. Inoculating the cucumber seedlings with GP15-1 significantly reduced the damping-off disease caused by Rhizoctonia solani, and the disease suppression effects of GP15-1 were considerably influenced by the inoculum potential of both GP15-1 and the pathogen. Treatment with the barley grain inoculum or a cell-free filtrate of GP15-1 increased systemic resistance against leaf infection by the anthracnose pathogen Colletotrichum orbiculare, resulting in a significant decrease in lesion number and size. Molecular and phylogenetic analyses of internal transcribed spacer sequences of the genomic DNA of GP15-1 revealed that the fungal isolate is a strain of either Penicillium neoechinulatum or Penicillium viridicatum.

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As a new liquid crystal and organogelator, cholesteryl 4-(alkanoylamino)benzoates were prepared. Cholesteryl 4-(alkanoylamino)benzoates had enantiotropic cholesteric and chiral smectic C phases. Furthermore cholesteryl 4-(alkanoylamino)benzoates gelled organic liquid such as 1-decanol, linalool, geraniol, nerol, citronellol, linalyl acetate, lavender oil, orange oil, and rose oil. The terpene and perfume gels show good release characteristics of the volatile components for a long period.

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The molecular interactions of monolayers composed of cyclic and linear forms of surfactins (SFs) were evaluated through atomic force microscopy (AFM) together with a Langmuir monolayer technique. The surface pressure (π)-area per molecule (A) isotherm of a pure cyclic surfactin (CSF) monolayer exhibited a liquid expanded (Le) monolayer, while that of a pure linear surfactin (LSF) monolayer exhibited a liquid condensed (Lc) monolayer, demonstrating that the CSFs are in a rather loose molecular packing state owing to its bulky heptapeptide ring. The plots of the mean area per molecule of the CSF/LSF monolayers were well fitted to the ideal curves, suggesting that ideal mixing occurs, or that the two components are immiscible in a monolayer. The AFM images of the CSF/LSF monolayers transferred at 25 mN/m gave phase-separated microdomain structures, indicating that the CSFs and LSFs are almost immiscible and separated into a CSF-rich and LSF-rich phases, as suggested from the analysis of the mean area per molecule of the monolayers. Our results clearly demonstrated that the cleavage of the cyclic heptapeptide headgroup of CSF drastically changes its molecular packing state in a monolayer and that AFM observation combined with the Langmuir monolayer technique is quite useful to explore the manner of self-assembly of a binary system of microbial products such as CSFs and LSFs.

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This study investigates the aggregation behavior of caseinate and the solubilization of genistein in aqueous caseinate solution. The critical aggregation concentration (CAC) of caseinate was obtained from the fluorescence intensity of 8-anilino-1-naphthalenesulfonic acid (ANS), which was enhanced by ANS-protein interactions and the hydrophobicity of caseinate. The increasing solubility of genistein in caseinate was confirmed by HPLC measurements; above and below the CAC, the genistein/caseinate molar ratio is 1:1 and 10:1, respectively. The latter ratio indicates that more caseinate molecules surround genistein below the CAC. However, the solubility of genistein in caseinate is unaffected by calcium ions. Atomic force microscopy (AFM) shows that casein sub-micelles are similarly structured in the presence and absence of genistein. In AFM phase images, the caseinate sub-micelle is brightened in the presence of genistein, implying that the particle becomes more rigid, probably because genistein attaches to the surface or to the narrow part of the sub-micelle. The diameter of sub-micelle aggregates is two times that of caseinate alone (24 nm versus 12 nm). These results were confirmed by cryo-TEM observations.

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