Fatty Acids in Heterocyclic Synthesis. Part XIV: Synthesis of Surface Active Agents from Some Novel Class of Oxadiazole,Thiadiazole and Triazole Derivatives Having Microbiological Activities

Reaction of stearic acid with semicarbazide in refluxing POCl₃ afforded 2-amino-5-heptadecyl 1,3,4-oxadiazole. Acylation of the amino group with acetic anhydride, ethyl chloroacetate and chloroacetic acid gave amide and β-amino acid derivatives. These compounds were cyclized to imidazo[2,1-b]oxadiazole derivatives by two different techniques. Treating the starting oxadiazole compound with P₂S₅, hydroxyl amine and hydrazine hydrate in benzene afforded thiadiazole and triazole derivatives. Unexpectedly, triazolo[3,4-b][1,3,4]oxadiazole derivative was obtained when 1,3,4-oxadiazole derivative was refluxed with hydrazine hydrate in ethanol. The biological activities of the synthesized compounds were screened in vitro against some gram positive and gram negative bacteria and fungi. Addition of quantitative amount of propylene oxide units (3, 5, 7 mol) to the synthesized compounds afforded new nonionic surfactants. The physico-chemical and surface properties of the novel synthesized surfactants such as surface and interfacial tension, cloud point, wetting time, emulsion stability, foam height, CMC, resistance to hydrolysis and their biodegradability were investigated. In addition, surface parameters including effectiveness (π _CMC), efficiency (PC₂₀), maximum surface excess (Γ_max) and (A _min) were examined.     

Synthesis and Characterization of Novel Surfactants: Combination Products of Fatty Acids,Hydroxycarboxylic Acids and Alcohols

The reaction of hydroxycarboxylic acids, such as citric, malic and tartaric species with an excess of fatty acid chlorides produces the corresponding O-acylated hydroxycarboxylic anhydrides in one step and in a near quantitative yield. These molecules are excellent electrophiles which react readily with a variety of nucleophiles including alcohols, diols and polyols. Their reaction with triethylene glycol and triethylene glycol monomethyl ether leads to two series of novel anionic surfactants, which are unsymmetrical gemini surfactants. The determination of their properties (CMC, foaming, HLB) revealed that these molecules are—depending on the chain length of the fatty acid—excellent emulsifiers, and that they also display interesting antimicrobial activity. These novel functional surfactants are of interest for applications in food and personal care products and for the formulation of pharmaceuticals.     

Nonionic Isatin Surfactants: Synthesis,Quantum Chemical Calculations,ADMET and Their Antimicrobial Activities

The most challenge task in the building up of surface-active molecules is maximizing their surface activity with good biological activity. A nonionic surfactant (N-isatin-EO _m-C _n where m is 5, 7 and 9 ethylene glycol units and n is 8, 10 and 12) is achieved by first reacting isatin with chloroacetic acid and then with different types of ethoxylated (C₈–C₁₂) fatty alcohols that possess 5, 7 and 9 ethylene oxide units. The prepared surfactants were characterized by FTIR and ¹H NMR to confirm the structure. The surface activity, biodegradability, antimicrobial, and antifungal activity of the surfactants were evaluated. In addition, quantum chemical calculations and computations of oral bioavailability were performed. The obtained data show that all the synthesized compounds had good surface activity, biodegradability and biological activity.     

Hydroxy Sulfonated Fatty Acid Esters as Surface Active Agents IV: Surfactants from Mixed Fatty Acids of Fish,Rice Bran and Cottonseed Oils

The preparation and properties of a few surface-active sulfonated monoglycerides derived from fish-, rice bran- and cottonseed oils are reported.     

Retracted: Synthesis,Characterization, and Surface Activities of Polymeric Cationic Thiol Surfactants in Aqueous Medium

A series of cationic polyurethane surfactants [PQ_8-18] were synthesized by the reaction of alkyl bromoacetate (namely: octyl-, decyl-, dodecyl-, tetradecyl-, hexadecyl-, and octadecyl bromoacetate) as quaternizing agents and modified polyurethane contains tertiary amine species. Modified polyurethane was prepared by the reaction of toluene diisocyanate (TDI) and triethanol amine monomercaptoacetate. The chemical structures of the prepared surfactants were confirmed using elemental analysis, Fourier transform infrared spectroscopy (FTIR), and Proton nuclear magnetic resonance (¹H NMR) spectroscopy. The molecular weight measurements of the prepared polymers showed that the segments of each polymer contain average 10 units of the urethane-triethanol amine mercaptoacetate. The surface activities of the prepared surfactants including: surface tension (γ), effectiveness ( π_cmc), concentration at micelle formation (CMC), efficiency (Pc₂₀), maximum concentration at the interface (Γ_max), and the average area occupied by each surfactant molecule at the interface at equilibrium ( A _min) of surfactants solutions were established at 25°C. The surface tension and the critical micelle concentration values of the prepared surfactants were gradually decreased by the gradual increase of their alkyl chain length. The prepared cationic surfactants showed efficient activity as inhibitors for dissolution of carbon steel in an acidic medium and also as a biocide against the growth of bacteria, fungi, and yeast.     

Green Synthesis of Endolichenic Fungi Functionalized Silver Nanoparticles: The Role in Antimicrobial,Anti-Cancer,and Mosquitocidal Activities

Green nanotechnology is currently a very crucial and indispensable technology for handling diverse problems regarding the living planet. The concoction of reactive oxygen species (ROS) and biologically synthesized silver nanoparticles (AgNPs) has opened new insights in cancer therapy. The current investigation caters to the concept of the involvement of a novel eco-friendly avenue to produce AgNPs employing the wild endolichenic fungus Talaromyces funiculosus. The synthesized Talaromyces funiculosus–AgNPs were evaluated with the aid of UV visible spectroscopy, dynamic light scattering (DLS), Fourier infrared spectroscopy (ATR-FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The synthesized Talaromyces funiculosus–AgNPs (TF-AgNPs) exhibited hemo-compatibility as evidenced by a hemolytic assay. Further, they were evaluated for their efficacy against foodborne pathogens Staphylococcus aureus, Streptococcus faecalis, Listeria innocua, and Micrococcus luteus and nosocomial Pseudomonas aeruginosa, Escherichia coli, Vibrio cholerae, and Bacillus subtilis bacterial strains. The synthesized TF-AgNPs displayed cytotoxicity in a dose-dependent manner against MDA-MB-231 breast carcinoma cells and eventually condensed the chromatin material observed through the Hoechst 33342 stain. Subsequent analysis using flow cytometry and fluorescence microscopy provided the inference of a possible role of intracellular ROS (OH⁻, O⁻, H₂O₂, and O₂⁻) radicals in the destruction of mitochondria, DNA machinery, the nucleus, and overall damage of the cellular machinery of breast cancerous cells. The combined effect of predation by the cyclopoid copepod Mesocyclops aspericornis and TF-AgNPS for the larval management of dengue vectors were provided. A promising larval control was evident after the conjunction of both predatory organisms and bio-fabricated nanoparticles. Thus, this study provides a novel, cost-effective, extracellular approach of TF-AgNPs production with hemo-compatible, antioxidant, and antimicrobial efficacy against both human and foodborne pathogens with cytotoxicity (dose dependent) towards MDA-MB-231 breast carcinoma.     

红发夫酵母细胞内蛋白质、脂肪酸与虾青素合成关系的研究

为研究红发夫酵母细胞内虾青素合成与蛋白质和脂肪酸代谢之间的关系,实验测定了发酵过程中蛋白质、脂肪酸和虾青素含量的变化。实验结果表明:红发夫酵母细胞内蛋白质的含量在整个发酵周期内变化非常显著,在0～16h(延滞期)和58～76h(指数生长后期)上升,而在16～58h(指数期)和76～124h(稳定期后期)下降。脂肪酸的含量变化趋势与蛋白质的基本相似,但是在稳定期表现出先快速上升然后迅速下降的变化特征。相比之下,虾青素含量的变化规律与蛋白质和脂肪酸相反。上述变化规律表明红发夫酵母细胞内虾青素的合成与蛋白质和脂肪酸的代谢密切相关。在延滞期和稳定前期蛋白质和脂肪酸的快速合成会减少流向虾青素合成方向的碳通量,使虾青素含量减少;而在稳定期后期底物耗尽出现碳饥饿时,蛋白质和脂肪酸的降解又为虾青素的进一步合成提供了碳骨架,提高了虾青素的含量。     

Analytical Problems in the Investigation of Unsaturated Acids Conversion II: Determination of Position Isomers,Conjugated Unsaturated Bonds and Composition of Fatty Acids

The paper discusses the methods of determination of the position of unsaturated bonds in a chain of acids, the determination of the sum of conjugated unsaturated bonds and the composition of the fatty acids. The position of unsaturated bonds in acids of modified oils may be determined most quickly by the method of pyrrolidide derivatives and determinations by the GLCMS method. The content of conjugated bonds had been determined by standardized method of UV spectrometry, and the composition of the fatty acids had been determined by gas chromatography.     

Statistical Analysis of the Collaborative Study in Support of the Official Method AOCS Ce 1i-07: Determination of Saturated, cis-Monounsaturated and cis-Polyunsaturated Fatty Acids in Marine and Other Oils Containing Long Chain Polyunsaturated Fatty Acids by Capillary GLC

Analysis was done of the statistical results obtained by following recommended AOCS Collaborative Study Procedure M-86 to evaluate the performance of Official Method AOCS Ce 1i-07, which provides a gas–liquid chromatography (GLC) procedure for the determination of the fatty acid composition of oils containing long chain polyunsaturated fatty acids (PUFAs). The method obtains relative between-lab reproducibility (%RSDR) values on the order of 5% or less for most fatty acids that are present above ~0.5% w/w; however, the reproducibility worsens dramatically for analytes below this threshold. Apparently, several participating labs had problems identifying small peaks in the sample chromatograms. They also had problems correctly identifying certain larger peaks that occurred in a congested area of the sample chromatograms, including the 9c-16:1, 9c-11c-22:1, and 6c,9c,12c,15c-16:4 fatty acids. Finally, several analytes with chain lengths between 16 and 18 and between 21 and 22 carbons that were present at moderate concentrations had worse than expected reproducibilities due to severe overlap of these analytes’ peaks. A detailed inspection of the contributed data shows that the relatively poor between-lab reproducibility for analytes in this region is due to differences in the labs’ chromatographic efficiencies and perhaps in their methods of quantifying highly overlapped peaks.     

Green Adeptness in the Synthesis and Stabilization of Copper Nanoparticles: Catalytic,Antibacterial, Cytotoxicity,and Antioxidant Activities

Copper nanoparticles (CuNPs) are of great interest due to their extraordinary properties such as high surface-to-volume ratio, high yield strength, ductility, hardness, flexibility, and rigidity. CuNPs show catalytic, antibacterial, antioxidant, and antifungal activities along with cytotoxicity and anticancer properties in many different applications. Many physical and chemical methods have been used to synthesize nanoparticles including laser ablation, microwave-assisted process, sol-gel, co-precipitation, pulsed wire discharge, vacuum vapor deposition, high-energy irradiation, lithography, mechanical milling, photochemical reduction, electrochemistry, electrospray synthesis, hydrothermal reaction, microemulsion, and chemical reduction. Phytosynthesis of nanoparticles has been suggested as a valuable alternative to physical and chemical methods due to low cytotoxicity, economic prospects, environment-friendly, enhanced biocompatibility, and high antioxidant and antimicrobial activities. The review explains characterization techniques, their main role, limitations, and sensitivity used in the preparation of CuNPs. An overview of techniques used in the synthesis of CuNPs, synthesis procedure, reaction parameters which affect the properties of synthesized CuNPs, and a screening analysis which is used to identify phytochemicals in different plants is presented from the recent published literature which has been reviewed and summarized. Hypothetical mechanisms of reduction of the copper ion by quercetin, stabilization of copper nanoparticles by santin, antimicrobial activity, and reduction of 4-nitrophenol with diagrammatic illustrations are given. The main purpose of this review was to summarize the data of plants used for the synthesis of CuNPs and open a new pathway for researchers to investigate those plants which have not been used in the past.

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Graphical abstract Proposed Mechanism for Antibacterial activity of copper nanoparticles.

     

ER Unfolded Protein Response in Liver In Vivo Is Characterized by Reduced,Not Increased,De Novo Lipogenesis and Cholesterol Synthesis Rates with Uptake of Fatty Acids from Adipose Tissue: Integrated Gene Expression,Translation Rates and Metabolic Fluxes

The unfolded protein response in the endoplasmic reticulum (UPR^ER) is involved in a number of metabolic diseases. Here, we characterize UPR^ER-induced metabolic changes in mouse livers in vivo through metabolic labeling and mass spectrometric analysis of lipid and proteome-wide fluxes. We induced UPR^ER by tunicamycin administration and measured synthesis rates of proteins, fatty acids and cholesterol, as well as RNA-seq. Contrary to reports in isolated cells, hepatic de novo lipogenesis and cholesterogenesis were markedly reduced, as were mRNA levels and synthesis rates of lipogenic proteins. H&E staining showed enrichment with lipid droplets while electron microscopy revealed ER morphological changes. Interestingly, the pre-labeling of adipose tissue prior to UPR^ER induction resulted in the redistribution of labeled fatty acids from adipose tissue to the liver, with replacement by unlabeled glycerol in the liver acylglycerides, indicating that the liver uptake was of free fatty acids, not whole glycerolipids. The redistribution of adipose fatty acids to the liver was not explicable by altered plasma insulin, increased fatty acid levels (lipolysis) or by reduced food intake. Synthesis of most liver proteins was suppressed under UPR^ER conditions, with the exception of BiP, other chaperones, protein disulfide isomerases, and proteins of ribosomal biogenesis. Protein synthesis rates generally, but not always, paralleled changes in mRNA. In summary, this combined approach, linking static changes with fluxes, revealed an integrated reduction of lipid and cholesterol synthesis pathways, from gene expression to translation and metabolic flux rates, under UPR^ER conditions. The reduced lipogenesis does not parallel human fatty liver disease. This approach provides powerful tools to characterize metabolic processes underlying hepatic UPR^ER in vivo.     

The Free Fatty Acid Content of Fish Oil,Part IV: Rates of Free Fatty Acid Formation from Phospholipids and Neutral Lipids in Anchovy (Engraulis capensis) Stored at Various Temperatures

Anchovy were stored at 17°C, 8°C, 0°C and ?6°C. Samples were withdrawn periodically and the extracted lipids analysed for free fatty acids (FFA) and phosphorus (P) content. From the results of these analyses it was possible to calculate the rates of enzymatic hydrolysis of the phospholipids and the neutral lipids. Phospholipids hydrolysed much faster than neutral lipids at the four temperatures. An Arrhenius plot showed that at about –29°C the two rates were identical.     

New polymer syntheses,Part 44: Synthesis,characterization, and corrosion inhibition behavior of new polyurea derivatives based on diaryl ether in the polymers backbone

A new interesting class of polyurea derivatives 5 _a‐c was synthesized using solution polycondensation technique by the interaction of 1 mol of 4,4′‐bis(2″‐aminothiazol‐4″‐yl)diphenyl ether monomer 3 with 1 mol of diisocyanate compounds in pyridine. The model compound 4 was synthesized by the interaction of 1 mol of monomers 3 with 2 mol of phenylisocyanate in pyridine, and the structure was confirmed by correct elemental and spectral analyses. The resulting polymers were characterized by elemental and spectral analyses besides solubility and viscometry measurements. The thermal properties of those polymers were evaluated by TGA, DTG, and DTA measurements and correlated to their structural units. In addition, the morphological properties of a selected example were tested by SEM, and the electrical properties of these polymers were measured. On the other hand, the corrosion inhibition properties of selected example of polyurea derivatives were carried out on steel in 0.5M H₂SO₄ at 40°C giving cathodic inhibition. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Efficient Synthesis of the Very-Long-Chain n-3 Fatty Acids,Tetracosahexaenoic Acid (C<Subscript>24</Subscript>:6n-3) and Tricosahexaenoic Acid (C<Subscript>23</Subscript>:6n-3)

Tetracosahexaenoic acid (C₂₄:6n-3, THA, 3) is an essential biosynthetic precursor in mammals of docosahexaenoic acid (C₂₂:6n-3, DHA, 1), the end-product of the metabolism of n-3 fatty acids. THA 3 is present in commercially valuable fishes, such as flathead flounder. Tricosahexaenoic acid (C₂₃:6n-3, TrHA, 2), an odd-numbered-chain fatty acid, has been identified from marine organisms such as the dinoflagellate, Amphidinium carterae. To date, few studies have examined THA 3 and TrHA 2 due to difficulties in detecting and identifying these compounds, so their chemical and biological properties remain poorly characterized. Only one methodology for the chemical synthesis of THA 3 has been presented, and no method for the synthesis of TrHA 2 has been reported. We report here the efficient synthesis of THA 3 in four steps in 56% overall yield, and the synthesis of TrHA 2 in six steps in 48% overall yield. We also present the synthesis of Δ²-THA 4, an intermediate of β-oxidation of THA 3 to DHA 1, in three steps in 73% overall yield.     

Quantification of emissions from the co-incineration of cutting oil emulsions in cement plants – Part I: NOx,CO and VOC

The paper provides an overall assessment of the environmental effects of co-incineration of cutting oil emulsions in cement plants through the quantification of emissions of key pollutants, namely NO_x, CO and VOC. Two realistic scenarios are considered. In the first, the cutting oil emulsion is injected directly into the rotary kiln while the second scenario involves injection of the cutting oil emulsion in the tertiary air stream and thus directly into the precalciner. A detailed kinetic PSR modelling study is performed for combustion conditions relevant both to cement kiln and precalciner operating conditions. It is demonstrated that, although NO_x emissions from the precalciner are generally substantially lower than those from the cement kiln, emulsion injection in the latter appears to be favourable and can lead up to 50% reductions in NO levels. However, injection of cutting oil emulsion with relatively high nitrogen content in the precalciner may lead, under lean conditions, to increases in the emitted NO levels. The effect of cutting oil emulsion on CO and VOC emissions both under cement kiln and precalciner conditions is also quantified.     

First Bovine Serum Albumin‐Promoted Synthesis of Enones,Cinnamic Acids and Coumarins in Ionic Liquid: An Insight into the Role of Protein Impurities in Porcine Pancreas Lipase for Olefinic Bond Formation

During studies on exploiting the catalytic promiscuity of crude porcine pancreas lipase (PPL) in ionic liquid for CC bond formations, bovine serum albumin (BSA) was found to be competing for these reactions. After a detailed investigation, we establish that these transformations are possible by unspecific protein catalysis rather than catalytic promiscuity of “PPL” – a first insight into the role of protein impurities in crude enzyme. Thus, a novel and highly efficient, environmentally friendly approach involving synergistic catalysis by bovine serum albumin‐1‐butyl‐3‐methylimidazolium bromide (BSA‐[bmim]Br) has been developed for the synthesis of (E)‐α,β‐unsaturated compounds including a one‐pot cascade synthesis of cinnamic acids and coumarins via aldol, Knoevenagel and Knoevenagel–Doebner condensations.     

Synthesis of alcohols from carbon oxides and hydrogen: XVIII. Preparation chemistry,phase transformations and catalytic behaviour of unpromoted MnCrO systems in the synthesis ofalcohols from carbon monoxide and hydrogen

Unpromoted MnCrO catalysts with manganese-to-chromium (Mn/Cr) atomic ratios ranging from 0.5 to 5 have been prepared and characterized by XRD, IR, UV-VIS diffuse reflectance, differential thermal analysis-thermogravimetric analysis and surface area measurements. The preparation chemistry is based on the redox reaction 3Mn^II+Cr^VI→3 Mn^III+Cr^III and the phase transformations occurring during activation depend on the Mn/Cr ratio and the annealing atmosphere. Activation in air at 400–600°C results in the formation either of α-Cr₂O₃ and a spinel phase or of α-Mn₂O₃ for low and high Mn/Cr ratios, respectively. Activation in hydrogen at similar temperatures results in the formation of MnCr₂O₄ for Mn/Cr = 0.5 and of an MnO-type phase for high Mn/Cr ratios, which is pyrophoric when exposed to air at room temperature. Activation in nitrogen is most suited for the preparation of MnCrO catalysts because it prevents both pyrophoric effects and the formation of oxides of Mn and Cr, which are known to catalyse the formation of undesirable reaction products during the synthesis of higher alcohols. Activation in air at higher temperature causes the disappearance of α-Cr₂O₃ and α-Mn₂O₃ and the formation of a spinel-like phase; for high manganese contents a tetragonal distortion of the cubic spinel phase is observed owing to the Jahn-Teller stabilization of octahedrally coordinated Mn^III. In the synthesis of higher alcohols, (i) Mn/Cr ratios > 0.5 ensure high activity in methanol synthesis, (ii) high Mn/Cr ratios depress the productivity with respect to ethers and methane because of the lower surface acidity and (iii) irrespective of the Mn/Cr ratio, all MnCrO catalysts are effective systems for the water-gas shift reaction.