Influence of Cationic Interactions on Fatty Acid Monolayers Studied by Ellipsometry

1989 ◽  
Vol 177 ◽  
Author(s):  
Mahn Won Kim ◽  
Bryan B. Sauer ◽  
Hyuk Yu ◽  
Mehran Yazdanian ◽  
George Zografi

ABSTRACTOptical properties of fatty acid monolayers were measured as a function of surface density and under the influence of cations in the aqueous substrate. The monolayer behavior of pentadecanoic acid (C15) on an aqueous solution of HCl at pH=2.0 was studied. The change in the ellipsometric phase angle δΔ was mildly affected by increases in surface density at constant orientation but strongly influenced by the liquid-expanded/solid phase transition presumably due to a change in conformation.The increase in the ellipsometric phase angle 6Δ with chain length C15, C16, C18, and C22 was attributed to an increase in thickness of fatty acids at the air/water interface. Separating the effect of optical density of head groups, the refractive indices calculated from the chain length data were independent of ionic environment. The magnitude of δΔ for fatty acids on aqueous substrates increased in the order HCl, CdCl2, and PbCl2. This was due to an increase in the refractive index of fatty acid head groups caused by association of divalent cations. Ellipsometry was also found to be a useful technique to monitor in-situ the degree of divalent cation association.

LWT ◽  
2021 ◽  
pp. 110867
Author(s):  
Min Hyeock Lee ◽  
Ha Ram Kim ◽  
Woo Su Lim ◽  
Min-Cheol Kang ◽  
Hee-Don Choi ◽  
...  

1988 ◽  
Vol 250 (3) ◽  
pp. 819-825 ◽  
Author(s):  
E P Brass ◽  
R A Beyerinck

Accumulation of propionate, or its metabolic product propionyl-CoA, can disrupt normal cellular metabolism. The present study examined the effects of propionate, or propionyl-CoA generated during the oxidation of odd-chain-length fatty acids, on hepatic oxidation of short- and medium-chain-length fatty acids. In isolated hepatocytes, ketone-body formation from odd-chain-length fatty acids was slow as compared with even-chain-length fatty acid substrates, and increased as the carbon chain length was increased from five to seven to nine. In contrast, rates of ketogenesis from butyrate, hexonoate and octanoate were all approximately equal. Propionate (10 mM) inhibited ketogenesis from butyrate, hexanoate and octanoate by 81%, 53% and 18% respectively. Addition of carnitine had no effect on ketogenesis from the even-chain-length fatty acids, but increased the rate of ketone-body formation from pentanoate (by 53%), heptanoate (by 28%) and from butyrate or hexanoate in the presence of propionate. The inhibitory effect of propionate could not be explained by shunting acetyl-CoA into the tricarboxylic acid cycle, as CO2 formation from butyrate was also decreased by propionate. Examination of the hepatocyte CoA pool during oxidation of butyrate demonstrated that addition of propionate decreased acetyl-CoA and CoA as propionyl-CoA accumulated. Addition of carnitine decreased propionyl-CoA by 50% (associated with production of propionylcarnitine) and increased acetyl-CoA and CoA. Similar changes in the CoA pool were seen during the oxidation of pentanoate. These results demonstrate that accumulation of propionyl-CoA results in inhibition of short-chain fatty acid oxidation. Carnitine can partially reverse this inhibition. Changes in the hepatocyte CoA pool are consistent with carnitine acting by generating propionylcarnitine, thereby decreasing propionyl-CoA and increasing availability of free CoA. The data provide further evidence of the potential cellular toxicity from organic acid accretion, and supports the concept that carnitine's interaction with the cellular CoA pool can have a beneficial effect on cellular metabolism and function under conditions of unusual organic acid accumulation.


2016 ◽  
Vol 78 (5-6) ◽  
Author(s):  
Mohd Basyaruddin Abdul Rahman ◽  
Siti Salhah Othman ◽  
Noor Mona Md Yunus

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. 


Molecules ◽  
2019 ◽  
Vol 24 (8) ◽  
pp. 1616 ◽  
Author(s):  
Alessandro Genovese ◽  
Andrea Marrazzo ◽  
Lucia De Luca ◽  
Raffaele Romano ◽  
Nadia Manzo ◽  
...  

Seed inoculation of forage crops by arbuscular mycorrhizal fungi (AMF) generally results in higher profitability, but also modifies the chemical composition of silage in terms of increased biomass, protein, and dry matter. Raw milk aroma is affected by the type of feed. This work investigated the influence of ensiled forage obtained by seed inoculation with AMF on the volatile fractions and fatty acid composition of milk. Two experiments were carried out: in the first, buffaloes were fed maize silage, and in the second, cows were fed sorghum silage. The volatile fractions of milk were quantified by headspace solid-phase micro-extraction (HS-SPME), combined with gas chromatography–mass spectrometry (GC-MS), and fatty acids by gas chromatography (GC). The ensiled forage obtained with AMF increased saturated fatty acids (SFAs), and decreased monounsaturated fatty acids (MUFAs) and polyunsaturated fatty acids (PUFAs) in both experiments. The volatile fraction in milk samples obtained from bovines fed mycorrhizal ensiled forage showed an increase of free fatty acids and ketones, responsible for cheesy and fruity odors. Aldehydes, responsible for green and grassy notes, increased only in the milk from buffaloes fed ensiled maize. Our results suggest that inoculation of maize and sorghum seed with AMF, combined with a low rate of fertilizers, leads to ensiled forage that could slightly affect the FA profile and odor quality of milk.


Cosmetics ◽  
2019 ◽  
Vol 6 (3) ◽  
pp. 45 ◽  
Author(s):  
Dorota Dobler ◽  
Thomas Schmidts ◽  
Sören Wildenhain ◽  
Ilona Seewald ◽  
Michael Merzhäuser ◽  
...  

Human skin is a complex ecosystem and is host to a large number of microorganisms. When the bacterial ecosystem is balanced and differentiated, skin remains healthy. However, the use of cosmetics can change this balance and promote the appearance of skin diseases. The skin’s microorganisms can utilize some cosmetic components, which either promote their growth, or produce metabolites that influence the skin environment. In this study, we tested the ability of the Malassezia species and some bacterial strains to assimilate substances frequently used in dermal formulations. The growth capability of microorganisms was determined and their lipase activity was analyzed. The growth of all Malassezia spp. in the presence of free acids, free acid esters, and fatty alcohols with a fatty chain length above 12 carbon atoms was observed. No growth was observed in the presence of fatty alcohol ethers, secondary fatty alcohols, paraffin- and silicon-based substances, polymers, polyethylene glycols, quaternary ammonium salts, hydroxy fatty acid esters, or fatty acids and fatty acid esters with a fatty chain length shorter than 12 carbon atoms. The hydrolysis of esters by Malassezia lipases was detected using High Performance Thin Layer Chromatography (HPTLC). The production of free fatty acids as well as fatty alcohols was observed. The growth promotion or inhibition of bacterial strains was only found in the presence of a few ingredients. Based on these results, formulations containing microbiome inert ingredients were developed.


Nutrients ◽  
2020 ◽  
Vol 12 (5) ◽  
pp. 1232
Author(s):  
Agnieszka Stawarska ◽  
Małgorzata Jelińska ◽  
Julia Czaja ◽  
Ewelina Pacześniak ◽  
Barbara Bobrowska-Korczak

Fatty acids, especially polyunsaturated, and their metabolites (eicosanoids) play many pivotal roles in human body, influencing various physiological and pathological processes. The aim of the study was to evaluate the effect of supplementation with edible oils diverse in terms of fatty acid composition on fatty acid contents, activities of converting their enzymes, and on lipoxygenase metabolites of arachidonic and linoleic acids (eicosanoids) in rat serum. Female Sprague-Dawley rats divided into seven groups were used in the study. Animals from six groups were fed one of oils daily (carotino oil, made up by combining of red palm oil and canola oil, linseed oil, olive oil, rice oil, sesame oil, or sunflower oil). One group received a standard diet only. Fatty acids were determined using gas chromatography with flame ionization detection. Eicosanoids—hydroxyeicosatetraenoic (HETE) and hydroxyoctadecadienoic acids (HODE) were extracted using a solid-phase extraction method and analyzed with HPLC. Vegetable oils given daily to rats caused significant changes in serum fatty acid profile and eicosanoid concentrations. Significant differences were also found in desaturases’ activity, with the linseed and olive oil supplemented groups characterized by the highest D6D and D5D activity. These findings may play a significant role in various pathological states.


2014 ◽  
Vol 11 (14) ◽  
pp. 3729-3738 ◽  
Author(s):  
K. E. Larkin ◽  
A. J. Gooday ◽  
C. Woulds ◽  
R. M. Jeffreys ◽  
M. Schwartz ◽  
...  

Abstract. Foraminifera are an important component of benthic communities in oxygen-depleted settings, where they potentially play a significant role in the processing of organic matter. We tracked the uptake of a 13C-labelled algal food source into individual fatty acids in the benthic foraminiferal species Uvigerina ex. gr. semiornata from the Arabian Sea oxygen minimum zone (OMZ). The tracer experiments were conducted on the Pakistan margin during the late/post monsoon period (August–October 2003). A monoculture of the diatom Thalassiosira weisflogii was 13C-labelled and used to simulate a pulse of phytoplankton in two complementary experiments. A lander system was used for in situ incubations at 140 m water depth and for 2.5 days in duration. Shipboard laboratory incubations of cores collected at 140 m incorporated an oxystat system to maintain ambient dissolved oxygen concentrations and were terminated after 5 days. Uptake of diatoms was rapid, with a high incorporation of diatom fatty acids into foraminifera after ~ 2 days in both experiments. Ingestion of the diatom food source was indicated by the increase over time in the quantity of diatom biomarker fatty acids in the foraminifera and by the high percentage of 13C in many of the fatty acids present at the endpoint of both in situ and laboratory-based experiments. These results indicate that


1991 ◽  
Vol 260 (2) ◽  
pp. L44-L51 ◽  
Author(s):  
K. J. Longmuir ◽  
S. Haynes

This study was undertaken to determine those structural features of phospholipid molecules which influence their enrichment in type II cell lamellar body material. Cultured fetal rabbit lung tissue was labeled with [1-14C]acetate, type II cells were isolated, and extracellular lamellar body and microsomal fractions were prepared. Radiolabeled molecular species of phosphatidylcholine (PC) and phosphatidylethanolamine were analyzed by high-performance liquid chromatography (HPLC), followed by silver nitrate thin-layer chromatography of HPLC peak fractions that overlapped. Compared with microsomes, lamellar body PC was selectively enriched with molecular species containing 14- and 16-carbon fatty acids and depleted of species containing 18-carbon fatty acids. Palmitoleic acid and an ether linkage positively influenced the enrichment of PC molecular species in the lamellar body material, but these structural features were secondary to the predominant influence of fatty acid chain length. In vivo, lung tissue normally contains low levels of palmitoleic acid; hence most unsaturated fatty acids are 18-carbons or longer. A cellular lipid-sorting mechanism that selects PCs by recognition of 14- and 16-carbon fatty acid chains (and not by recognition of fatty acid saturation) should serve to enrich the resulting pulmonary surfactant with disaturated molecular species of PC.


1982 ◽  
Vol 204 (3) ◽  
pp. 749-756 ◽  
Author(s):  
M C Sugden ◽  
D I Watts ◽  
C E Marshall

1. Injection of adrenaline into 24 h-starved rats caused a 69% decrease in blood [ketone-body] (3-hydroxybutyrate plus acetoacetate), accompanied by a decreased [3-hydroxybutyrate]/[acetoacetate] ratio. Blood [glucose] and [lactate] increased, but [alanine] was unchanged. 2. Adrenaline also decreased [ketone-body] after intragastric feeding of both long- and medium-chain triacylglycerol. The latter decrease was observed after suppression of lipolysis with 5-methylpyrazole-3-carboxylic acid, indicating that the antiketogenic action of adrenaline was not dependent on the chain length of the precursor fatty acid. 3. The actions of adrenaline to decrease blood [ketone-body] and to increase blood [glucose] were not observed after administration of 3-mercaptopicolinate, an inhibitor of gluconeogenesis. This suggests that these effects of the hormone are related. 4. The possible clinical significance of the results is discussed with reference to the restricted ketosis often observed after surgical or orthopaedic injury.


2000 ◽  
Vol 28 (6) ◽  
pp. 855-856 ◽  
Author(s):  
J. Edqvist ◽  
I. Farbos

In Euphorbia lagascae the major fatty acid in triacylglycerol is the epoxidated fatty acid vernolic acid (cis- 12-epoxyoctadeca-cis-9-enoic acid). The enzymic reactions occurring during the catabolism of epoxidated fatty acids during germination are not known, but it seems likely that the degradation requires the activity of an epoxide hydrolase. Epoxide hydrolases are a group of functionally related enzymes that catalyse the cofactor-independent hydrolysis of epoxides to their corresponding vicinal diols by the addition of a water molecule. Here we report the cloning and characterization of an epoxide hydrolase gene from E. lagascae. The structure of the gene is unusual since it lacks introns. A detailed investigation of the transcription pattern of the epoxide hydrolase gene shows that the gene is induced during germination. We have used in situ hybridization to identify in which tissues the gene is expressed during germination. We speculate that this epoxide hydrolase enzyme is involved in the catabolism of epoxidated fatty acids during germination of E. lagascae seeds.


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