Ternary Solubility Phase Diagrams of Mandelic Acid andN-Methylephedrine in Chiral Solvents with Different Carbon Chain Lengths

2010 ◽  
Vol 10 (9) ◽  
pp. 4023-4029 ◽  
Author(s):  
Samuel Kofi Tulashie ◽  
Heike Lorenz ◽  
Chandrakant Ramkrishna Malwade ◽  
Andreas Seidel-Morgenstern
Keyword(s):  
Phase Diagrams ◽  
Mandelic Acid ◽  
Carbon Chain ◽  
Ternary Solubility ◽  
Chain Lengths

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 However, recent work by Cuddeford and Mayes (unpublished) has found that in horses the faecal recovery rates are similar regardless of chain lengths.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.

scholarly journals Biochemical Characterization of CYP505D6, a Self-Sufficient Cytochrome P450 from the White-Rot FungusPhanerochaete chrysosporium

2018 ◽  
Vol 84 (22) ◽  
Author(s):  
Kiyota Sakai ◽  
Fumiko Matsuzaki ◽  
Lisa Wise ◽  
Yu Sakai ◽  
Sadanari Jindou ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Cytochrome P450 ◽  
Phanerochaete Chrysosporium ◽  
Carbon Chain ◽  
Fatty Alcohols ◽  
White Rot ◽  
Wild Type ◽  
Content Type ◽  
Attractive Candidate ◽  
Chain Lengths

ABSTRACTThe activity of a self-sufficient cytochrome P450 enzyme, CYP505D6, from the lignin-degrading basidiomycetePhanerochaete chrysosporiumwas characterized. Recombinant CYP505D6 was produced inEscherichia coliand purified. In the presence of NADPH, CYP505D6 used a series of saturated fatty alcohols with C9–18carbon chain lengths as the substrates. Hydroxylation occurred at the ω-1 to ω-6 positions of such substrates with C9–15carbon chain lengths, except for 1-dodecanol, which was hydroxylated at the ω-1 to ω-7 positions. Fatty acids were also substrates of CYP505D6. Based on the sequence alignment, the corresponding amino acid of Tyr51, which is located at the entrance to the active-site pocket in CYP102A1, was Val51 in CYP505D6. To understand the diverse hydroxylation mechanism, wild-type CYP505D6 and its V51Y variant and wild-type CYP102A1 and its Y51V variant were generated, and the products of their reaction with dodecanoic acid were analyzed. Compared with wild-type CYP505D6, its V51Y variant generated few products hydroxylated at the ω-4 to ω-6 positions. The products generated by wild-type CYP102A1 were hydroxylated at the ω-1 to ω-4 positions, whereas its Y51V variant generated ω-1 to ω-7 hydroxydodecanoic acids. These observations indicated that Val51 plays an important role in determining the regiospecificity of fatty acid hydroxylation, at least that at the ω-4 to ω-6 positions. Aromatic compounds, such as naphthalene and 1-naphthol, were also hydroxylated by CYP505D6. These findings highlight a unique broad substrate spectrum of CYP505D6, rendering it an attractive candidate enzyme for the biotechnological industry.IMPORTANCEPhanerochaete chrysosporiumis a white-rot fungus whose metabolism of lignin, aromatic pollutants, and lipids has been most extensively studied. This fungus harbors 154 cytochrome P450-encoding genes in the genome. As evidenced in this study,P. chrysosporiumCYP505D6, a fused protein of P450 and its reductase, hydroxylates fatty alcohols (C9–15) and fatty acids (C9–15) at the ω-1 to ω-7 or ω-1 to ω-6 positions, respectively. Naphthalene and 1-naphthol were also hydroxylated, indicating that the substrate specificity of CYP505D6 is broader than those of the known fused proteins CYP102A1 and CYP505A1. The substrate versatility of CYP505D6 makes this enzyme an attractive candidate for biotechnological applications.

scholarly journals SELECTIVITY OF CANDIDA RUGOSA LIPASE IMMOBILIZED ONTO LAYERED DOUBLE HYDROXIDES AS CATALYST IN SYNTHESIS OF FATTY ACID ESTERS

2016 ◽  
Vol 78 (5-6) ◽  
Author(s):  
Mohd Basyaruddin Abdul Rahman ◽  
Siti Salhah Othman ◽  
Noor Mona Md Yunus
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Chain Length ◽  
Candida Rugosa ◽  
Candida Rugosa Lipase ◽  
Carbon Chain ◽  
Fatty Acid Esters ◽  
Carbon Chain Length ◽  
Chain Lengths ◽  
Acid Esters

The enzymatic selectivity of Lipase from Candida rugosa immobilized onto a calcined layered double hydroxide (CLDHs-CRL) towards the chain-length of fatty acids and alcohols in the synthesis of fatty acid esters was investigated.  The results showed that CMAN-CRL catalyzed the esterification process with fatty acids of medium chain lengths (C10-C14) effectively while, CNAN-CRL and CZAN-CRL exhibited high percentage conversion in fatty acids with carbon chain lengths of C8-C12 and C10-C18, respectively. In the alcohol selectivity study, CMAN-CRL showed high selectivity toward alcohols with carbon chain lengths of C4, C6 and C10.  On the other hand, both CNAN-CRL and CZAN-CRL exhibited rather low selectivity towards longer carbon chain length of alcohols. 

Electrochemical degradation of perfluoroalkyl and polyfluoroalkyl substances (PFASs) in groundwater

2015 ◽  
Vol 71 (10) ◽  
pp. 1569-1575 ◽  
Author(s):  
A. M. Trautmann ◽  
H. Schell ◽  
K. R. Schmidt ◽  
K.-M. Mangold ◽  
A. Tiehm
Keyword(s):  
Carbon Chain ◽  
Contaminated Groundwater ◽  
Carbon Chain Length ◽  
Order Kinetic ◽  
Electrochemical Degradation ◽  
Boron Doped Diamond ◽  
Polyfluoroalkyl Substances ◽  
Hazardous Pollutants ◽  
Chain Lengths ◽  
Perfluoroalkyl And Polyfluoroalkyl Substances

Perfluoroalkyl and polyfluoroalkyl substances (PFASs) represent hazardous pollutants and are frequently detected in the environment, e.g. in contaminated groundwater. PFASs are persistent to biodegradation and conventional oxidation processes such as ozonation. In this study electrochemical degradation of PFASs on boron-doped diamond (BDD) electrodes is demonstrated. Experiments were performed with model solutions and contaminated groundwater with a dissolved organic carbon (DOC) content of 13 mg/L. The perfluorinated carboxylic acids (PFCAs) perfluorobutanoate, perfluoropentanoate, perfluorohexanoate, perfluoroheptanoate and perfluorooctanoate, and the perfluorinated sulfonic acids (PFSAs) perfluorobutane sulfonate, perfluorohexane sulfonate, perfluorooctane sulfonate and 6:2 fluorotelomer sulfonate were detected in the groundwater samples. At PFAS concentrations ranging from 0.26 to 34 mg/L (0.7 to 79 μM), the degradation of PFASs was achieved despite of the high DOC background. Pseudo first-order kinetic constants of PFSA degradation increased with the increase of carbon chain length. Fluoride formation as well as the generation of PFCAs with shortened chain lengths was observed. Inorganic byproducts such as perchlorate were also formed and have to be considered in further process optimization.

scholarly journals The occurrence of polyenoic very long chain fatty acids with greater than 32 carbon atoms in molecular species of phosphatidylcholine in normal and peroxisome-deficient (Zellweger's syndrome) brain

1988 ◽  
Vol 253 (3) ◽  
pp. 645-650 ◽  
Author(s):  
A Poulos ◽  
P Sharp ◽  
D Johnson ◽  
C Easton
Keyword(s):  
Fatty Acids ◽  
Molecular Species ◽  
Carbon Chain ◽  
Normal Brain ◽  
Long Chain Fatty Acids ◽  
Brain Physiology ◽  
Chain Lengths ◽  
The Brain ◽  
Long Chain ◽  
Chain Fatty Acids

The n-6 tetra- and pentaenoic fatty acids with carbon chain lengths greater than 32 found in normal brain are located predominantly in a separable species of phosphatidylcholine. A similar phospholipid is found in increased amounts in the brain of peroxisome-deficient (Zellweger's syndrome) patients, but the fatty acid composition differs in that penta- and hexaenoic derivatives predominate. Our data strongly suggest that the polyenoic very long chain fatty acids are confined to the sn-1 position of the glycerol moiety, while the sn-2 position is enriched in saturated, monounsaturated and polyunsaturated fatty acids with less than 24 carbon atoms. It is postulated that these unusual molecular species of phosphatidylcholine may play some, as yet undefined, role in brain physiology.

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