Abstract  Experimental data on the partitioning of amino acids (tryptophan, phenylalanine) and dipeptides (tryptophan-leucine, phenylalanine-leucine) between the aqueous feed phase and the organic solvent phase are presented. The organic solvent phase consists of a carrier, sodium di-2-ethylhexyl sulfosuccinate/quaternary ammonium salt/dioleyl phosphoric acid, dissolved in (Z)-9-octadecen-1-ol (an organic solvent). The equilibrium distribution coefficient for extractions is determined by varying the following experimental conditions: feed solution pH, initial feed phase concentration, and composition of organic phase. The partition coefficient for the stripping process is also determined by varying the stripping agent (sodium hydroxide, sodium chloride, sodium carbonate), the concentration, and the pH of the stripping solution. The extraction and stripping reaction coefficients are calculated by combining the experimental data and the kinetic expressions for interfacial reactions. The variation of the values of the coefficients with the solute type (i.e. amino acid or dipeptide) and with the operating conditions of the system di-2-ethylhexyl sulfosuccinate in (Z)-9-octadecen-1-ol is presented.

Abstract  Seven chemically designed monolayer compounds were synthesized and investigated with comparison to the properties and water evaporation suppression ability of 1-hexadecanol and 1-octadecanol. Increasing the molecular weight and polarity of the compound headgroup drastically altered the characteristics and performance of the monolayer at the air/water interface. Contrary to the common expectation the monolayer's lifetime on the water surface decreased with increasing number of ethylene oxy moieties, thus optimal performance for water evaporation suppression was achieved when only one ethylene oxy moiety was used. Replacing the hydroxyl headgroup with a methyl group and with multiple ethylene oxy moieties resulted in a loss of suppression capability, while an additional hydroxyl group provided a molecule with limited performance against water evaporation. Theoretical molecular simulation demonstrated that for exceptional performance, a candidate needs to possess a high equilibrium spreading pressure, the ability to sustain a highly ordered monolayer with a stable isotherm curve, and low tilt angle over the full studied range of surface pressures by simultaneously maintaining H-bonding to the water surface and between the monolayer chains. (C) 2012 Elsevier B.V. All rights reserved.

Abstract  PURPOSE: Microemulsion (ME) systems allow for the microscopic co-incorporation of aqueous and organic phase liquids. In this study, the phase diagrams of four novel ME systems were characterized.

METHODS: Water and IPM composed the aqueous and organic phases respectively, whereas Tween 80 served as a nonionic surfactant. Transdermal enhancers such as n-methyl pyrrolidone (NMP) and oleyl alcohol were incorporated into all systems without disruption of the stable emulsion.

RESULTS: A comparison of a W/O ME with an O/W ME of the same system for lidocaine delivery indicated that the O/W ME provides significantly greater flux (p < 0.025). The water phase was found to be a crucial component for flux of hydrophobic drugs (lidocaine free base, estradiol) as well as hydrophilic drugs (lidocaine HCl, diltiazem HCl). Furthermore, the simultaneous delivery of both a hydrophilic drug and a hydrophobic drug from the ME system is indistinguishable from either drug alone. Enhancement of drug permeability from the O/W ME system was 17-fold for lidocaine free base, 30-fold for lidocaine HCl, 58-fold for estradiol, and 520-fold for diltiazem HCl.

CONCLUSIONS: The novel microemulsion systems in this study potentially offers many beneficial characteristics for transdermal drug delivery.

Abstract  This paper presents the effect of adding different amounts of zinc into the composition of Zn-Mn/oleylamine core/shell ferrite nanoparticles (NPs). For this purpose, acetylacetonate as a main precursor, oleylamine as a surfactant and surface modifier, and stearyl alcohol as a co-surfactant were used for thermal decomposition synthesis of this ferrite. Monodispersed core/shell ferrite NPs synthesized with several compositions. The X-ray diffraction (XRD) patterns and transmission electron microscopy (TEM) images showed single-phase nanoparticles around 10 nm without any impurities. Fourier Transform Infrared Spectroscopy (FTIR) confirmed single-phase spinel with ultra-thin layers of oleylamine on the surfaces that make the particles separated from each other. Thermogravimetric studies could also measure the amount of surfactant around the NPs. Moreover, the DC magnetic properties of the samples were studied using the vibrating sample magnetometer (VSM). The M-H curves for all the samples showed negligible hysteresis loops indicating the superparamagnetic behaviour of the NPs. Furthermore, maximum saturation magnetization was measured for the sample with Mn0.6Zn0.4Fe2O4 with 45 amu.gr(-1), suggesting that this composition could be an excellent candidate for biomedical applications such as hyperthermia and imaging. (C) 2016 Elsevier B.V. All rights reserved.

Abstract  OBJECTIVE: To investigate the effect of Pygeum africanum (PA) extract on the proliferation of cultured human prostatic myofibroblasts and fibroblasts; this extract is used for treating urinary disorders associated with benign prostatic hyperplasia (BPH).

MATERIALS AND METHODS: Primary cultures of prostatic stromal cells were obtained from histologically confirmed human BPH by enzymatic digestion. Cell proliferation was measured by 5-bromo2'-deoxy-uridine (BrdU) incorporation assays, and cytotoxicity by luminescent quantification of adenylate kinase activity.

RESULTS: Cultured cells were labelled by an anti-vimentin antibody, and most of them by an alpha-smooth-muscle-actin antibody, revealing the presence of fibroblasts and myofibroblasts. BrdU incorporation tests showed that proliferation of cultured human stromal cells, stimulated by fetal calf serum, by basic fibroblast growth factor and by epidermal growth factor, was dose-dependently inhibited by PA extract (5-100 microg/mL). Except at 100 microg/mL, no acute cytotoxicity of the extract was detected after 24 h of culture. Similarly, the extract dose-dependently inhibited the proliferation of Madin-Darby canine kidney epithelial cells, but to a lesser extent; whatever the dose of extract, no acute toxicity was evident on this cell line.

CONCLUSION: PA extract inhibits the proliferation of cultured human prostatic myofibroblasts and fibroblasts. We propose that cultured human prostatic cells offer a reliable model for preclinical screening of therapeutic agents, and to study the mechanisms underlying the inhibition of proliferation.

Abstract  The hydrogenation of methyl oleate (methyl cis-9-octadecenoate) to oleyl alcohol (methyl cis-9-octadecen-1-ol) was studied in the presence of a bimetallic CoSn supported over zinc oxide catalyst in a stainless steel batch reactor at 270 degrees C and 8.0 MPa of hydrogen. The active species in the reduction of methyl oleate into unsaturated alcohols was CoSn2. In order to increase the amount of these active species the nature of the precursor salts was studied. These results have shown that the carbonyl cobalt precursor is the optimum salt for the hydrogenation of methyl oleate into unsaturated alcohol since the selectivity to unsaturated alcohol reached 55% at 80% of conversion. Moreover, the selectivity is governed by the reduction of the heavy esters (oleyl oleate and oleyl stearate) formed, which can occur in the presence of small Co-Sn-2 particles, well dispersed on the catalyst surface and with a high surface content. (C) 2012 Elsevier B.V. All rights reserved.

Abstract  The amount and characterization of phytosterol and other minor components present in three Indian minor seed oils, mahua (Madhuca latifolia), sal (Shorea robusta) and mango kernel (Mangifera indica), have been done. Theses oils have shown commercial importance as cocoa-butter substitutes because of their high symmetrical triglycerides content. The conventional thin layer chromatography (TLC), gas chromatography (GC) & gas chromatography-mass spectroscopy (GC-MS) techniques were used to characterize the components and the high performance thin layer chromatography (HPTLC) technique was used to quantify the each group of components. The experimental data showed that the all the three oils are rich in sterol content and among all the sterols, beta-sitosterol occupies the highest amount. Sal oil contains appreciable amount of cardenolides, gitoxigenin. Tocopherol is present only in mahua oil and oleyl alcohol is present in mango kernel oil. Hydrocarbon, squalene, is present in all the three oils. The characterization of these minor components will help to detect the presence of the particular oil in specific formulations and to assess its stability as well as nutritional quality of the specific oil.

Abstract  The magnetic needle interfacial shear rheometer is a valuable tool for the study of the mechanical properties of thin fluid films or monolayers. However, it is difficult to differentiate the interfacial and subphase contributions to the drag on the needle. In principle, the problem can be addressed by decreasing the needle diameter, which decreases the bulk contribution while the interfacial contribution remains essentially the same. Here we show the results obtained when using a new type of needle, that of magnetic microwires with diameter approximately 10 times thinner than for commercial needles. We show that the lower inertia of the microwires calls for a new calibration procedure. We propose such a new calibration procedure based on the flow field solution around the needle introduced in refs 1 and 2. By measuring thin silicone oil films with well-controlled interfacial viscosities as well as eicosanol (C20) and pentadecanoic acid (PDA, C15) Langmuir monolayers, we show that the new calibration method works well for standard needles as well as for the microwire probes. Moreover, we show that the analysis of the force terms contributing to the force on the needle helps to ascertain whether the measurements obtained are reliable for given surface shear viscosity values. We also show that the microwire probes have at least a 10-fold-lower resolution limit, allowing one to measure interfacial viscosities as low as 10(-7) N·m/s.

Abstract  The primary objective was to characterize Indian Coriandrum sativum L. foliage (Vulgare alef and Microcarpum DC varieties) and its radical scavenging activity. Foliage of Vulgare alef and Microcarpum DC contained ascorbic acid (1.16 ± 0.35 and 1.22 ± 0.54 mg/g), total carotenoids (1.49 ± 0.38 and 3.08 ± 1.2 mg/g), chlorophyll 'a' (8.23 ± 2.4 and 12.18 ± 2.9 mg/g), chlorophyll 'b' (2.74 ± 0.8 and 4.39 ± 1.3 mg/g) and total chlorophyll (10.97 ± 2.6 and 16.57 ± 3.2 mg/g). The polyphenol content was 26.75 ± 1.85 and 30.00 ± 2.64 mg/g in Vulgare alef and Microcarpum DC, respectively. Ethanol extracts (200 ppm) of alef and Microcarpum DC showed higher radical scavenging activity of 42.05 ± 2.42 % and 62.79 ± 1.36 % when compared with 95 % butylated hydroxyanisole. The principal component analysis results indicated that e-nose can distinguish the volatiles effectively. Quantitative descriptive sensory analysis showed that Microcarpum DC variety is superior to Vulgare alef variety. Nearly 90 % of the flavour compounds present were identified by GC-MS in both varieties. The principal component identified in both the varieties were decanal (7.645 and 7.74 %), decanol < n- > (25.12 and 39.35 %), undecanal (1.20 and 1.75 %), dodecanal (7.07 and 2.61 %), tridecen-1-al < 2E > (6.67 and 1.21 %), dodecen-1-ol < 2E- > (16.68 and 8.05 %), 13-tetradecenal (9.53 and 8.60 %), tetradecanal (5.61 and 4.35 %) and 1-octadecanol (1.25 and 3.67 %).

Abstract  The genus Astragalus is a rich source of a variety of biologically active compounds including phenols, saponins, polysaccharides and essential oils. The present study was conducted to determine ontogenetic variation of the volatile organic compounds as well as total phenolic contents and antioxidant activity in leaves of A. compactus. The leaves of plant were harvested at vegetative, flowering and fructification stages and were analyzed by gas chromatography coupled with mass spectrometry (GC-MS). Total phenolic content (TPC) was determined using the Folin-Ciocalteau reagent and the antioxidant capacity was evaluated with the 1,1-diphenyl-2-picrylhydrazyl (DPPH) test. Different classes of volatile compounds were identified including alcohols, esters, hydrocarbons, sterols and terpenoides. Significant variation of these compounds was found during phenological stages of development. Sterols and hydrocarbons were the main components of essential oils at the vegetative stage. The presence of terpenoides (phytol) and alcohols (docosanol) was significant at the flowering stage. Fructification phase was characterized by the high content of sterols and hydrocarbons and absence of phytol. The antioxidant activity and phenolic content were related to the physiological stage and the highest amount detected at fructification phase. The ontogenetic variations of phenolic contents and antioxidant properties are largely contributed by climatic factors such as temperature and solar radiation.

Abstract  Maleic anhydride was modified with long chain alcohols (1-hexadecanol, 1-octadecanol, 1-eicosanol and docosyl) to their corresponding amphiphilic mono-L cis-butene dicarboxylates (L = hexadecyl, octadecyl, eicosyl and docosyl). Subsequently, corresponding amphiphilic lanthanide (Y3+, Eu3+) complexes with these four mono-L cis-butene dicarboxylate ligands [Ln(L')3, Ln = Eu, Y; L' = MAH, MAO, MAE, MAD] were synthesized. Then, under heating at various temperatures (700, 800, 900, 1000, and 1,100 degrees C), twenty kinds of nanosized Y2O3:Eu3+ phosphors were prepared using these four as-derived amphiphilic lanthanide (Y3+, Eu3+) complexes as precursors. All four complexes can form nanosized micelle-like aggregates by special self-assembly. Results show that, under heating at 1,000 degrees C, the four Y2O3:Eu3+ phosphors present more regular dispersion particle-like morphology, and the particle size is in the range of 30-80 nm. They exhibit an especially strong emission at 609 nm, and the luminescence intensity of the sample derived from MAD at 1,000 degrees C is best.

Abstract  Surface layers of natural and technical amphiphiles, e.g., octadecanol, stearic acid and related compounds as well as perfluorinated fatty alcohols (PFA), have been investigated on the surface of acoustically levitated drops. In contrast to Langmuir troughs, traditionally used in the research of surface layers at the air-water interface, acoustic levitation offers the advantages of a minimized and contact-less technique. Although the film pressure cannot be directly adjusted on acoustically levitated drops, it runs through a wide pressure range due to the shrinking surface of an evaporating drop. During this process, different states of the generated surface layer have been identified, in particular the phase transition from the gaseous or liquid-expanded to the liquid-condensed state of surface layers of octadecanol and other related amphiphiles. Characteristic parameters, such as the relative permeation resistance and the area per molecule in a condensed surface layer, have been quantified and were found comparable to results obtained from surface layers generated on Langmuir troughs.

Abstract  The primary and secondary objectives of this study were to develop and evaluate the predictability of in vitro-in vivo correlation models for theophylline sustained release (SR) granules. Theophylline SR granules meeting the USP Drug Release Test criteria were prepared using ethyl cellulose (EC) and/or stearyl alcohol (SA) and the wet granulation method. In vitro dissolution studies of granule formulation were performed, and a commercial dosage form was prepared using USP XXIII apparatus II at pH 4.5. Differences and similarities between in vitro dissolution curves were compared using both model-dependent (t-test) and -independent (f1, f2 test) statistical techniques, and it was shown that the three dissolution profiles i.e model-dependent, model-independent, and methods based on ANOVA were very similar. The in vivo performance of the commercial dosage form was tested by oral route using male rabbits and in vitro-in vivo correlations were established. This study indicates that the dosage forms with similar in vitro dissolution profiles may have a similar in vivo performance, and that this performance could be estimated using appropriate correlation equations.

Abstract  Oleyl alcohol was complexed with new amphiphilic polyvinylalcohol derivatives with the aim of increasing its aqueous solubility, thus improving bioavailability and favoring its antitumor activity. Water-soluble amphiphilic polymers were prepared by polyvinyl alcohol (PVA) substitution with oleyl chains through a succinyl spacer at 2% and 3% substitution degree. The complexes were obtained by spray-drying hydroalcoholic solutions of the substituted polymers and free oleyl alcohol at different weight ratios (3:1; 5:1; 10:1 w/w). The main physicochemical characteristics of the complexes were analyzed and correlated to the cytotoxic activity of oleyl alcohol toward tumor cell lines. The complexes strongly increased the aqueous solubility of oleyl alcohol and provided oleyl alcohol release in the presence of extractive conditions (simulating in vivo absorption). The complexes obtained by 10:1 polymer:fatty alcohol weight ratio offered higher release rates than the 5:1 and 3:1 ratios, respectively. Complexation also increased oleyl alcohol cytotoxicity toward tumor cells due to increased availability of the active molecule in the aqueous phase. Pure polymers were found to be biocompatible and no toxic effect was detected up to the highest concentration used in the present study (500 mu g/ml). The complexation of oleyl alcohol with the polymers analyzed here efficiently increased the availability of the fatty alcohol in aqueous environment. The enhanced cytotoxicity toward tumor cells of the complexed oleyl alcohol and the polymer biocompatibility make these amphiphilic PVA derivatives interesting candidates for soluble pharmaceutical formulations containing hydrophobic drugs whose therapeutic potential is often underestimated due to unsuitable levels of their aqueous solubilization.

Abstract  Fast-disintegrating (FD) tablets containing nicorandil-loaded dry emulsions were prepared and their controlled-release properties were examined and compared with the plain FD tablets (FD tablets without dry emulsions) and commercial tablets. The dry emulsions were prepared with myristyl alcohol and stearyl alcohol and their property was modified by mixing the ratio of the two alcohols. Disintegration time of the prepared FD tablets was sufficiently fast (i.e., 12 to 23 s). In vitro release of nicorandil from the FD tablets containing the dry emulsions was sustained over 6 h, while that from plain FD and commercial tablets was complete within 5 min. In vivo absorption of nicorandil from the tablets was evaluated by oral administration in beagle dogs. FD tablets containing dry emulsions showed a similar AUC, lower Cmax, and delayed Tmax compared to the plain FD and commercial tablets. These results suggest that the dry emulsion-loaded FD tablets can be utilized to improve the sustained-release property of active drugs.

Abstract  It was shown by the combination of thermogravimetric analysis and Karl Fisher titrations that temperatures in excess of 200 degrees C are required to remove tightly bound water from proteins. The heating of enzymes to this temperature caused no cleavage of the polypeptide chains and very little, if any, chemical degradation of particular amino acid residues as judged by electrophoretic and amino acid analysis respectively. It was hypothesised that those enzymes that require very little water for their catalytic activity, should remain active at such elevated temperatures provided that they can be stabilised against thermodenaturation. This conclusion has been verified by the observation that immobilised Candida antarctica lipase catalysed transesterification of octadecanol with palmityl stearate at 130 degrees C for a considerable period of time.

Abstract  A two-phase aqueous/organic partitioning bioreactor scheme was used to degrade mixtures of toluene and benzene, and toluene and p-xylene, using simultaneous and sequential feeding strategies. The aqueous phase of the partitioning bioreactor contained Pseudomonas sp. ATCC 55595, an organism able to degrade benzene, toluene and p-xylene simultaneously. An industrial grade of oleyl alcohol served as the organic phase. In each experiment, the organic phase of the bioreactor was loaded with 10.15 g toluene, and either 2.0 g benzene or 2.1 g p-xylene. The resulting aqueous phase concentrations were 50 mg/l, 25 mg/l and 8 mg/l toluene, benzene and p-xylene respectively. The simultaneous fermentation of benzene and toluene consumed these compounds at volumetric rates of 0.024 g l-1 h-1 and 0.067 g l-1 h-1, respectively. The simultaneous fermentation of toluene and p-xylene consumed these xenobiotics at volumetric rates of 0.066 g l-1 h-1 and 0.018 g l-1 h-1, respectively. A sequential feeding strategy was employed in which toluene was added initially, but the benzene or p-xylene aliquot was added only after the cells had consumed half of the initial toluene concentration. This strategy was shown to improve overall degradation rates, and to reduce the stress on the microorganisms. In the sequential fermentation of benzene and toluene, the volumetric degradation rates were 0.056 g l-1 h-1 and 0.079 g l-1 h-1, respectively. In the toluene/p-xylene sequential fermentation, the initial toluene load was consumed before the p-xylene aliquot was consumed. After 12 h in which no p-xylene degradation was observed, a 4.0-g toluene aliquot was added, and p-xylene degradation resumed. Excluding that 12-h period, the microbes consumed toluene and p-xylene at volumetric rates of 0.074 g l-1 h-1 and 0.025 g l-1 h-1, respectively. Oxygen limitation occurred in all fermentations during the rapid growth phase.

Abstract  n-Docosanol-treated cells resist infection by a variety of lipid-enveloped viruses including the herpesviruses. Previous studies of the mechanism of action demonstrated that n-docosanol inhibits an event prior to the expression of intermediate early gene products but subsequent to HSV attachment. The studies reported here indicate that n-docosanol inhibits fusion of the HSV envelope with the plasma membrane. Evidence suggests that antiviral activity requires a time-dependent metabolic conversion of the compound. Cellular resistance to infection declines after removal of the drug with a t1/2 of approximately 3 h. Reduced expression of viral genes in n-docosanol-treated cells was confirmed by a 70% reduction in expression of a reporter gene regulated by a constitutive promoter inserted into the viral genome. Inhibited release in treated cells of virion-associated regulatory proteins--an immediate post entry event--was indicated by a 75% reduction in the expression of beta-galactosidase in target cells carrying a stably transfected lacZ gene under control of an HSV immediate--early promoter. Finally, the fusion-dependent dequenching of a lipophilic fluorescent probe, octadecyl rhodamine B chloride, inserted into the HSV envelope was significantly inhibited in treated cells. Inhibition of fusion between the plasma membrane and the HSV envelope, and the subsequent lack of replicative events, may be the predominant mechanism for the anti-HSV activity of n-docosanol.

Abstract  Solid-liquid equilibrium temperatures for tert-butanol + n-alkanes (C-18, C-19, C-20, C-21, C-22, C-23, C-24, C-25, C-26, C-28) systems have been measured by a dynamic method from 298.15 K to the melting point of the alkane. All the systems present an eutectic point at very low concentration of the alcohol. A first-order transition was observed for many of the n-alkanes considered. The experimental values are compared with those given by the DISQUAC model using the interaction parameters previously determined on the basis of vapor-liquid equilibria, VLE, and molar excess enthalpies, H-E, of systems containing the lower n-alkanes (n-C-6, n-C-7). Calculations were developed taking into account the solid-solid transition of the alkanes. The mean relative standard deviation for the equilibrium temperatures is 0.0073. Differences between experimental data and calculated results for SLE and H-E are analysed in terms of the Patterson effect. The possibility of improving predictions by modifying only the third dispersive interchange coefficient is discussed. Two values for this parameter are proposed depending on n, hereafter the number of C atoms in the n-alkane (n less than or equal to 8 and n greater than or equal to 9). In this way, the variation with the temperature of HE is better represented by the model for those systems including the longer n-alkanes. Predictions on SLE remain unchanged, because they depend essentially on the first interchange coefficients when the range of temperature considered, as in this case, is rather narrow. (C) 1998 Elsevier Science B.V. All rights reserved.

Abstract  This study was conducted at the Horticulture Department of Cukurova University, Adana, Turkey, in 2010 to determine the volatile aroma compounds of Morchella mushroom. Fresh samples of Morchella esculenta (Sample 1) and Morchella elata (Sample 2) were collected from Canakkale (Sample 1) and Mersin (Sample 2) provinces in Turkey in the spring of 2010. Volatile aroma compounds were analyzed by headspace gas chromatography mass spectrometry (HS-GC/MS). A total of 31 aroma compounds were identified in the 2 analyzed samples: 7 alcohols, 7 esters, 7 ketones, 3 acids, 2 aldehydes, 1 terpene, phenol, 1-propanamine, geranyl linalool, and quinoline. Seventeen aroma components were identified in Sample 1, and 18 compounds were found in Sample 2. Phenol was determined as the major aroma compound in both Sample 1 and Sample 2, at 50.888% and 58.293% content, respectively. Alcohols, especially 1-octen-3-ol, were detected as the second major aroma components in Sample 1 and Sample 2, at 15.500% and 5.660% content, respectively. Carbamic acid, methyl ester was found only in Sample 1, at 11.379% content. The aroma components detected in the two samples differed. 1-Octadecanol; cyclooctylalcohol; trans-2-undecen-1-ol; butanoic acid, butyl ester (CAS); carbamic acid, methyl ester; 2-ethylhexyl-2-echylhexanoate; phthalic acid, decyl isobutyl ester, 2,2,4-trimethyl-1,3-pentanediol diisobutyrate; decanal; nonanal; 7,9-di-tert-butyl-1-oxaspiro(4.5)deca-6,9-diene-2,8-dione; 2,5-cyclohexadiene-1,4-dione; 2,6-bis(1,1-dimethylethyl); and trans-alpha-bisabolene were detected only in Sample 1. Ethanol; silanediol, 2-methylaminoethanol; L-alanine, ethyl ester; carbonic acid, dodecyl isobutyl ester; acetic acid; butanoic acid; 2,3,4H-pyran-4-one; 5,9-undecadien-2-one; cyclooctene; 2-cyclopenten-1-one; 1-propanamine; geranyl linalool; and quinoline were determined only in Sample 2.

Abstract  The purpose of this work was to develop a novel polyurethane hydrogel system for sustained drug release, which could be used as a vaginal drug-delivery vehicle. The blank polyurethane hydrogels were synthesized by a polyol oligomeric, a diisocyanate and a triol (used as cross-linking agent). In order to improve the swelling ability of a polyurethane hydrogel, a small amount of 1-octadecanol was added. Additionally, the structure, mechanical properties and thermal properties of polymers were assessed by FT-IR, WAXD, DSC and mechanical tests. The results show that no more than 2.5 wt% of 1-octadecanol additives is sufficient to affect the release profile without changing the structure and mechanical properties of the polyurethane hydrogels obviously. Tinidazole was chosen as a model drug, the release data of drug from polyurethane hydrogels were fitted using the Ritger-Peppas equation and the result showed that it was non-Fickian diffusion, which means that the drug release was controlled by both swollen control and diffusion control. In conclusion, our work proves that the synthesized polyurethane hydrogel modified by 1-octadecanol may be a promising sustained release drug carrier.

Abstract  The reaction medium shows a significant effect on the distribution of alkane products for the hydro-deoxygenation of fatty acid methyl esters (FAMEs) over a bifunctional catalyst. Biodiesel-related methyl stearate was hydrodeoxygenated to heptadecane and octadecane over Ru/HZSM-5. In aqueous medium, heptadecane is a predominant product owing to a suppression effect of water on the octadecanol dehydration process. In the case of cyclohexane medium, the C-17/(C-17 + C-18) ratio significantly decreases with the temperature due to a promotion effect of reaction temperature on the octadecanol hydro-deoxygenation process. Our research results further reveal that solvent water can remarkably promote the methyl stearate-to-stearic acid transformation in the network of hydrodeoxygenation of methyl stearate via hydrolysis and hydrogenolysis steps. The hydrodeoxygenation temperature required for methyl stearate is approximately 40 degrees lower in water than in cyclohexane. The reaction pathway involves methyl stearate hydrogenolysis over Ru/HZSM-5 (in water or organic phase) and methyl stearate hydrolysis over HZSM-5 (in water) to generate stearic acid. Octadecanal is a key "intermediate" for subsequent stearic acid-to-octadecanol transformation and is responsible for heptadecane production via the decarbonylation pathway over Ru/HZSM-5, while hydrodeoxygenation of octadecanol leads to the formation of octadecane.

Abstract  In the present study, focused the antimicrobial compound production by the marine actinobacteria isolated from the mangrove sediments of Andaman Island. Streptomyces sp. DOSMB-A107 isolated from mangrove sediments of Andaman Island was identified by morphological, chemistry of cell wall and molecular characterization. Bioactive compounds were extracted with five different solvents and were identified using GC-MS analysis. Among the five different solvents ethyl acetate extract showed maximum activity against eleven bacteria and six fungal pathogens than other solvents. Twelve compounds were identified, off the following eight compounds such as 2-Butanol, 2-nitroso-, acetate(ester), Phenylethyl Alcohol, Phenol, 2,4-bis(1,1- dimethylethyl)-, 1-Hexadecanol, Pyrrolo[1,2a]pyrazine-1,4-dione, hexahydro-3- (2-methylpropy1)-, 1Hentetracontanol, 1-Eicosanol, Ergotaman-3',6',18-trione, 12'-hydroxy-2'-methyl-5' (phenylmethyl)-, (5'a)- were identified as anti-infective agent. Ethyl acetate would be a suitable solvent for the extraction of antimicrobial agents from Streptomyces.

Abstract  The effects of the oil phase as a mixture (binary, ternary) on the emulsion droplet size were investigated. The binary trials were performed with the aid of simplex lattice design with constraints. Droplet diameter was evaluated in terms of the oil phase viscosity and the interfacial tension between oil phase and the aqueous phase. As a result it could be shown that increasing the oil phase viscosity as a function of castor oil concentration led to a greater increase in particle size. At the same time, decreasing the interfacial tension of the oil phase as a function of oleic acid or oleic alcohol was shown to have a negligible effect on the particle size of the dispersed phase. A further aim was to find out a formulation by using a ternary oil phase resulting in a stable emulsion which could pass the autoclaving process. It was ascertained that oleic acid as a part of the oil phase led to proper formulation showing a satisfactory stability.