Morphology, Ionic-Molecular Interaction and Ionic Conductivity Behavior of PMMA/ENR 50 Electrolytes Containing Carboxylic Acids Modified SiO2 Fillers

2019 ◽  
Vol 821 ◽  
pp. 419-425
Author(s):  
Mohamad Zamri Sharil Fadli ◽  
Abdul Latif Famiza ◽  
Mohd Azuan Siti Izzati Husna
Keyword(s):  
Ionic Conductivity ◽  
Carboxylic Acids ◽  
Octanoic Acid ◽  
Silanol Group ◽  
Carbon Chain ◽  
Dodecanoic Acid ◽  
Casting Method ◽  
Acid Modification ◽  
Lithium Tetrafluoroborate ◽  
Chain Lengths

Carboxylic acids of various carbon chain lengths (Cn); i.e. butanoic acid (C4), octanoic acid (C8), dodecanoic acid (C12) and hexadecanoic acid (C16) have been used to organically modify silicon dioxide (SiO2). The acid modification involve replacing the hydrogen atom of the silanol group (Si-OH) of SiO2 with the RnCOO-of the acid via esterification technique. SiO2 and acid modified SiO2 (MoCn-SiO2) were used as filler in preparation of polymethyl methacrylate/50% epoxidized natural rubber electrolytes containing SiO2 (PEL-SiO2) and MoCn-SiO2 (PEL-MoCn-SiO2) via solvent casting method with lithium tetrafluoroborate (LiBF4) as dopant salt. Field-emission scanning electron microscopy (FESEM) analysis of PEL-SiO2 and PEL-MoCn-SiO2 films show LiBF4 accumulated to the fillers. Fourier-transform infrared spectroscopy (FTIR) analysis confirmed formation of hydrogen bonding between LiBF4 with fillers and polymers in the polymer electrolyte films. Interestingly, the ionic conductivity of PEL-MoCn-SiO2 films increases as the Cn of acids increased with the highest ionic conductivity of 5.56 x 10-7 Scm-1 was achieved in PEL-MoC12-SiO2 film.

scholarly journals Chemotaxis of Pseudomonas putida F1 to Alcohols Is Mediated by the Carboxylic Acid Receptor McfP

2019 ◽  
Vol 85 (22) ◽  
Author(s):  
Xiangsheng Zhang ◽  
Jonathan G. Hughes ◽  
Gabriel A. Subuyuj ◽  
Jayna L. Ditty ◽  
Rebecca E. Parales
Keyword(s):  
Pseudomonas Putida ◽  
Carboxylic Acids ◽  
Energy Sources ◽  
Specific Cell ◽  
Dodecanoic Acid ◽  
Fermentation Products ◽  
Content Type ◽  
Linear Chains ◽  
Chemotaxis Proteins ◽  
Chain Lengths

ABSTRACT Although alcohols are toxic to many microorganisms, they are good carbon and energy sources for some bacteria, including many pseudomonads. However, most studies that have examined chemosensory responses to alcohols have reported that alcohols are sensed as repellents, which is consistent with their toxic properties. In this study, we examined the chemotaxis of Pseudomonas putida strain F1 to n-alcohols with chain lengths of 1 to 12 carbons. P. putida F1 was attracted to all n-alcohols that served as growth substrates (C2 to C12) for the strain, and the responses were induced when cells were grown in the presence of alcohols. By assaying mutant strains lacking single or multiple methyl-accepting chemotaxis proteins, the receptor mediating the response to C2 to C12 alcohols was identified as McfP, the ortholog of the P. putida strain KT2440 receptor for C2 and C3 carboxylic acids. Besides being a requirement for the response to n-alcohols, McfP was required for the response of P. putida F1 to pyruvate, l-lactate, acetate, and propionate, which are detected by the KT2440 receptor, and the medium- and long-chain carboxylic acids hexanoic acid and dodecanoic acid. β-Galactosidase assays of P. putida F1 carrying an mcfP-lacZ transcriptional fusion showed that the mcfP gene is not induced in response to alcohols. Together, our results are consistent with the idea that the carboxylic acids generated from the oxidation of alcohols are the actual attractants sensed by McfP in P. putida F1, rather than the alcohols themselves. IMPORTANCE Alcohols, released as fermentation products and produced as intermediates in the catabolism of many organic compounds, including hydrocarbons and fatty acids, are common components of the microbial food web in soil and sediments. Although they serve as good carbon and energy sources for many soil bacteria, alcohols have primarily been reported to be repellents rather than attractants for motile bacteria. Little is known about how alcohols are sensed by microbes in the environment. We report here that catabolizable n-alcohols with linear chains of up to 12 carbons serve as attractants for the soil bacterium Pseudomonas putida, and rather than being detected directly, alcohols appear to be catabolized to acetate, which is then sensed by a specific cell-surface chemoreceptor protein.

scholarly journals Lactational Transfer of Long-Chain Perfluorinated Carboxylic Acids in Mice: A Method to Directly Collect Milk and Evaluate Chemical Transferability

Toxics ◽  
2020 ◽  
Vol 8 (2) ◽  
pp. 23
Author(s):  
Yukiko Fujii ◽  
Kouji H. Harada ◽  
Hatasu Kobayashi ◽  
Koichi Haraguchi ◽  
Akio Koizumi
Keyword(s):  
Carboxylic Acids ◽  
Daily Intake ◽  
Carbon Chain ◽  
Postnatal Period ◽  
Industrial Chemicals ◽  
P Concentration ◽  
Perfluorinated Carboxylic Acids ◽  
Lactational Transfer ◽  
Chain Lengths ◽  
Long Chain

Perfluoroalkyl carboxylic acids (PFCAs), such as perfluorooctanoic acid (PFOA, C8), are a group of industrial chemicals that are detected in the serum of people throughout the world. Long-chain PFCAs (C9 to C13) have high lipophilicity, therefore they may have a high transfer rate to breast milk. This study investigated the lactational transfer of PFCAs with carbon chain lengths of 8 to 13 in mice. Lactating dams were given a single intravenous administration of PFCAs (C8 to C13) during the postnatal period (8–13 days after delivery). Milk was collected from the dam 24 h after administration using a milking device built in-house. Plasma was obtained from the dam at the same time as milk collection. The observed milk/plasma (M/P) concentration ratios were 0.32 for C8, 0.30 for C9, 0.17 for C10, 0.21 for C11, 0.32 for C12, and 0.49 for C13. These results indicate that the M/P concentration ratio is not related to the lipophilicity of PFCAs. However, estimated relative daily intake, an indicator of how much PFCA is transferred from dams to pups per body weight, increased with chain length: 4.16 for C8, 8.98 for C9, 9.35 for C10, 9.51 for C11, 10.20 for C12, and 10.49 for C13, which may be related to the lower clearance of long-chain PFCAs. These results indicate the importance of future risk assessment of long-chain PFCAs.

scholarly journals Toxicokinetics of perfluoroalkyl carboxylic acids with different carbon chain lengths in mice and humans

2015 ◽  
Vol 57 (1) ◽  
pp. 1-12 ◽  
Author(s):  
Yukiko Fujii ◽  
Tamon Niisoe ◽  
Kouji H. Harada ◽  
Shinji Uemoto ◽  
Yasuhiro Ogura ◽  
...  
Keyword(s):  
Carboxylic Acids ◽  
Carbon Chain ◽  
Chain Lengths

Degrees of order of solubilized alkanes, alcohols, carboxylates, and carboxylic acids in oriented lyomesophases

1977 ◽  
Vol 55 (12) ◽  
pp. 2404-2410 ◽  
Author(s):  
Douglas M. Chen ◽  
Fred Y. Fujiwara ◽  
Leonard W. Reeves
Keyword(s):  
Carboxylic Acids ◽  
Chain Length ◽  
Linear Increase ◽  
Short Chain ◽  
Appreciable Amount ◽  
Linear Region ◽  
Short Chain Length ◽  
Chain Lengths ◽  
Degree Of Order ◽  
Limiting Value

The degree of order of solubilized molecules and ions in oriented lyomesophases has been determined at specifically deuterated C—D bond axes from the quadrupole splitting of the deuterium magnetic resonance. Mixtures at low concentration of specifically deuterated alkanes, alcohols, carboxylic acids, and carboxylates of different chain length have been observed in host cationic and anionic lyomesophases. The degree of order of a given C—D position in alcohols increases strongly with chain length up to a length comparable with the host detergent. A broad series of carboxylic acids and carboxylate ions from C2 to C16 have been deuterated in the α position. The α-C—D bond axis in the solubilisate increases in order with chain length, the anion having lower order than the parent acid. An accurately linear increase in the degree of order of the α position is observed for intermediate chain lengths. At chain lengths approximately equal to the host chain lengths the α position reaches a limiting value in the degree of order and further segments do not influence the order. At short chain lengths the degree of order is less than that predicted from extrapolation of order in the linear region. This has been interpreted in terms of distribution into the aqueous compartment by the solubilisates of short chain length. Acetic acid and the acetate, propionate, butanoate, and pentanoate ions spend an appreciable amount of time in the aqueous region. An estimate has been made of these distributions based on reasonable assumptions.

The Use of N-alkanes for Estimating Intake and Passage Rate in Horses

1996 ◽  
Vol 1996 ◽  
pp. 98-98
Author(s):  
B M L McLean ◽  
R W Mayes ◽  
F D DeB Hovell
Keyword(s):  
Recent Work ◽  
Chain Length ◽  
Carbon Chain ◽  
Carbon Chain Length ◽  
Passage Rate ◽  
Forage Crops ◽  
Carbon Chains ◽  
Naturally Occurring ◽  
Chain Lengths ◽  
Long Chain

Alkanes occur naturally in all plants, although forage crops tend to have higher alkane contents than cereals. N-alkanes have odd-numbered carbon chains. They are ideal for use as markers in feed trials, because, they are inert, indigestible and naturally occurring, and can be recovered in animal faeces. Synthetic alkanes (even-numbered carbon chains) are available commercially and can also used as external markers. Dove and Mayes (1991) cite evidence indicating that faecal recovery of alkanes in ruminants increases with increasing carbon-chain length. Thus the alkane “pairs” (e.g. C35 & C36, and C32 & C33) are used in calculating intake and digestibility because they are long chain and adjacent to each other. However, recent work by Cuddeford and Mayes (unpublished) has found that in horses the faecal recovery rates are similar regardless of chain lengths.

scholarly journals Terminal Olefin Profiles and Phylogenetic Analyses of Olefin Synthases of Diverse Cyanobacterial Species

2018 ◽  
Vol 84 (13) ◽  
Author(s):  
Tao Zhu ◽  
Thibault Scalvenzi ◽  
Nathalie Sassoon ◽  
Xuefeng Lu ◽  
Muriel Gugger
Keyword(s):  
Fatty Acid ◽  
Genetic Basis ◽  
Carbon Chain ◽  
Fatty Acyl ◽  
Carbon Chain Length ◽  
Substrate Activation ◽  
Chain Length Specificity ◽  
Modular Architectures ◽  
Terminal Olefins ◽  
Chain Lengths

ABSTRACT Cyanobacteria can synthesize alkanes and alkenes, which are considered to be infrastructure-compatible biofuels. In terms of physiological function, cyanobacterial hydrocarbons are thought to be essential for membrane flexibility for cell division, size, and growth. The genetic basis for the biosynthesis of terminal olefins (1-alkenes) is a modular type I polyketide synthase (PKS) termed olefin synthase (Ols). The modular architectures of Ols and structural characteristics of alkenes have been investigated only in a few species of the small percentage (approximately 10%) of cyanobacteria that harbor putative Ols pathways. In this study, investigations of the domains, modular architectures, and phylogenies of Ols in 28 cyanobacterial strains suggested distinctive pathway evolution. Structural feature analyses revealed 1-alkenes with three carbon chain lengths (C 15 , C 17 , and C 19 ). In addition, the total cellular fatty acid profile revealed the diversity of the carbon chain lengths, while the fatty acid feeding assay indicated substrate carbon chain length specificity of cyanobacterial Ols enzymes. Finally, in silico analyses suggested that the N terminus of the modular Ols enzyme exhibited characteristics typical of a fatty acyl-adenylate ligase (FAAL), suggesting a mechanism of fatty acid activation via the formation of acyl-adenylates. Our results shed new light on the diversity of cyanobacterial terminal olefins and a mechanism for substrate activation in the biosynthesis of these olefins. IMPORTANCE Cyanobacterial terminal olefins are hydrocarbons with promising applications as advanced biofuels. Despite the basic understanding of the genetic basis of olefin biosynthesis, the structural diversity and phylogeny of the key modular olefin synthase (Ols) have been poorly explored. An overview of the chemical structural traits of terminal olefins in cyanobacteria is provided in this study. In addition, we demonstrated by in vivo fatty acid feeding assays that cyanobacterial Ols enzymes might exhibit substrate carbon chain length specificity. Furthermore, by performing bioinformatic analyses, we observed that the substrate activation domain of Ols exhibited features typical of a fatty acyl-adenylate ligase (FAAL), which activates fatty acids by converting them to fatty acyl-adenylates. Our results provide further insight into the chemical structures of terminal olefins and further elucidate the mechanism of substrate activation for terminal olefin biosynthesis in cyanobacteria.

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