Presence Of Fatty Acids Research Articles

Optimization of palm oil extraction from decanter cake using Soxhlet extraction and effects of microwaves pre-treatment on extraction yield and physicochemical properties of palm oil

Response Surface Methodology (RSM) was applied to study the optimum condition of palm oil extraction from oil palm decanter cake (OPDC) using Soxhlet extraction and nhexane as solvent. The main objective of this study was to achieve maximum oil extraction by determining the optimum of two parameters such as reaction time and solid to solvent ratio. The optimum parameters were found to be at 4.92 hrs of reaction time and solid to solvent ratio of 1:10. The proposed model shows R2 value of 0.78 where the experimental parameters were significant to the result. The optimized data was employed for comparison of oil yield for OPDC without and with microwave pre-treatment. OPDC with microwave pre-treatment yielded 3.289±0.047 g of palm oil which was higher than OPDC without microwave pre-treatment which yielded only 3.107±0.085 g of palm oil. Fourier Transform Infrared Spectroscopy (FTIR) analysis also revealed the abundance of C-H alkene stretch and C=O stretch, two major functional groups indicated the presence of fatty acid within the palm oil derived from both samples. Scanning electron microscopy (SEM) of decanter cake provided evidence that the OPDC with pre-treatment has more shrinkage on the surface after Soxhlet extraction compared to OPDC without pretreatment. Results of this study revealed that RSM helps to optimize parameters in agricultural processing.

Daidzein stimulates fatty acid-induced fat deposition in C2C12 myoblast cells via the G protein-coupled receptor 30 pathway

Fat deposition in skeletal muscle is an important aspect of improving meat quality. Isoflavones can promote animal anabolism, but whether and how they regulate muscle fat deposition remain largely unclear. In this study, we explored the role and corresponding molecular mechanism of one of the major isoflavones, daidzein, in fat deposition in C2C12 myoblast cells. In the absence of fatty acids (FAs), daidzein did not promote triglyceride synthesis and lipid droplet formation in cells but increased sterol regulatory element-binding protein 1c (SREBP-1c) expression and maturation. In the presence of FAs, daidzein enhanced FAs-induced fat deposition and the SREBP-1c signaling. Daidzein promoted FAs-induced nuclear factor κB1 (NFκB1) phosphorylation and activated the SREBP-1c signaling in a PI3K-dependent manner. G protein-coupled receptor 30 (GPR30) knockdown but not estrogen receptor α (ERα) knockdown blocked the stimulation of daidzein on the PI3K-NFκB1-SREBP-1c signaling pathway, while both knockdown did not affect the stimulation of FAs on this signaling. qRT-PCR and ChIP-qPCR further detected that daidzein stimulated NFκB1-targeted SREBP-1c transcription. Daidzein did not affect ERα expression in cells, but it stimulated GPR30 expression and cytoplasmic localization. These results reveal that daidzein promotes FAs-induced fat deposition through the GPR30 signaling in C2C12 myoblast cells.

Binding of direct oral anticoagulants to the FA1 site of human serum albumin.

The anticoagulant therapy is widely used to prevent and treat thromboembolic events. Until the last decade, vitamin K antagonists were the only available oral anticoagulants; recently, direct oral anticoagulants (DOACs) have been developed. Since 55% to 95% of DOACs are bound to plasma proteins, the in silico docking and ligand-binding properties of drugs apixaban, betrixaban, dabigatran, edoxaban, and rivaroxaban and of the prodrug dabigatran etexilate to human serum albumin (HSA), the most abundant plasma protein, have been investigated. DOACs bind to the fatty acid (FA) site 1 (FA1) of ligand-free HSA, whereas they bind to the FA8 and FA9 sites of heme-Fe(III)- and myristic acid-bound HSA. DOACs binding to the FA1 site of ligand-free HSA has been validated by competitive inhibition of heme-Fe(III) recognition. Values of the dissociation equilibrium constant for DOACs binding to the FA1 site (ie, calc KDOAC ) derived from in silico docking simulations (ranging between 1.2 × 10-8 M and 1.4 × 10-6 M) agree with those determined experimentally from competitive inhibition of heme-Fe(III) binding (ie, exp KDOAC ; ranging between 2.5 × 10-7 M and 2.2 × 10-6 M). In addition, this study highlights the inequivalence of rivaroxaban binding to mammalian serum albumin. Given the HSA concentration in vivo (~7.5 × 10-4 M), values of KDOAC here determined indicate that the formation of the HSA:DOACs complexes in the absence and presence of FAs and heme-Fe(III) may occur in vivo. Therefore, HSA appears to be an important determinant for DOACs transport.

Synthesis and biological evaluation of 3,6-dialkylsubstituted-[1,2,4] triazolo[3,4-b][1,3,4]thiadiazoles

A series of 3,6-dialkyl-[1,2,4] triazolo[3,4-b][1,3,4]thiadiazole (10) analogues were prepared through multistep synthesis and evaluated them for their antimicrobial and cytotoxic activities. Synthesis of target compounds was carried out using undecenoic acid as starting material, which is the renewable product of castor oil. The key step in the synthesis was formation of triazolo [3,4-b][1,3,4]thiadiazole using various free fatty acids in presence of $$\hbox {POCl}_{3}$$ . It was observed that the undecenyl based triazolothiadiazole with butyl (6a), hexyl (6b) and lauryl (6f) derivatives exhibited promising antimicrobial activity against the tested strains. Particularly, Compound 6a exhibited the most promising activity with MIC value 3.9 $$\upmu \hbox {g}/\hbox {mL}$$ against most of the tested strains. It also showed potent minimum bactericidal concentration activity with MIC value 7.8 $$\upmu \hbox {g}/\hbox {mL}$$ against the tested strains. Cytotoxicity data revealed that most of the tested compounds revealed cytotoxic activity, Compounds 6b, 6d, 6f, 6g, 6h and 6i against SKOV3, 6d, 6e, 6f, 6g, 6h, 6i and 6j against MCF-7 and 6c, 6d, 6e,6g, 6h, 6i and6j against B16–F10 cell lines exhibited significant activities with $$\hbox {IC}_{50}$$ values ranged between 13.67 and 18.62 $$\upmu \hbox {M}$$ . Interestingly, all the compounds were non toxic against Chinese hamster ovary cell (CHO-K1) normal cell. A series of 3, 6-dialkyl triazolothiadiazole analogues were prepared using undecenoic acid, which is the renewable product of castor oil and evaluated them for their antimicrobial and cytotoxic activities. Few compounds showed good antimicrobial and cytotoxic activities.

Characterization of S-nitrosoglutathione reductase from Brassica and Lactuca spp. and its modulation during plant development

Cellular homeostasis of S-nitrosoglutathione (GSNO), a major cache of nitric oxide bioactivity in plants, is controlled by the NADH-dependent S-nitrosoglutathione reductase (GSNOR) belonging to the family of class III alcohol dehydrogenases (EC 1.1.1.1). GSNOR is a key regulator of S-nitrosothiol metabolism and is involved in plant responses to abiotic and biotic stresses. This study was focused on GSNOR from two important crop plants, cauliflower (Brassica oleracea var. botrytis, BoGSNOR) and lettuce (Lactuca sativa, LsGSNOR). Both purified recombinant GSNORs were characterized in vitro and found to exists as dimers, exhibit high thermal stability and substrate preference towards GSNO, although both enzymes have dehydrogenase activity with a broad range of long-chain alcohols and ω-hydroxy fatty acids in presence of NAD+. Data on enzyme affinities to their cofactors NADH and NAD+ obtained by isothermal titration calorimetry suggest the high affinity to NADH might underline the GSNOR capacity to function in the intracellular environment. GSNOR activity and gene expression peak during early developmental stages of lettuce and cauliflower at 20 and 30 days after germination, respectively. GSNOR activity was also measured in four other Lactuca spp. genotypes with different degree of resistance to biotrophic pathogen Bremia lactucae. Higher GSNOR activities were found in non-infected plants of susceptible genotypes L. sativa UCDM2 and L. serriola as compared to resistant genotypes. GSNOR and GSNO were localized by confocal laser scanning microscopy in vascular bundles and in epidermal and parenchymal cells of leaf cross-sections. The presented results bring new insight in the role of GSNOR in the regulation of S-nitrosothiol levels in plant growth and development.

Impact of environment on Red Blood Cell ability to withstand mechanical stress.

Susceptibility of red blood cells (RBC) to hemolysis under mechanical stress is represented by RBC mechanical fragility (MF), with different types or intensities of stress potentially emphasizing different perturbations of RBC membranes. RBC membrane mechanics were shown to depend on cell environment, with many details not yet understood. Here, stress was applied to RBC using a bead mill with oscillation up to 50 Hz, over durations up to 50 minutes. MF profiles plot percent lysis upon stresses of progressive durations. Supplementing media with polyethylene glycol (PEG) which interacts with the cell membrane, but not Dextran which does not, resulted in higher resistance to hemolysis. Albumin, and to a lesser extent fibrinogen and globulins (at physiological concentrations), significantly increased cell ability to withstand mechanical stress versus with un-supplemented buffer solution and with PEG. This is partly due to changes in rheology, per tests done including (PEG) and Dextran, but is mostly due to cell-protein interaction, noting the effect of pH on RBC MF with albumin but not with buffer. Presence of lipids reduced RBC resistance to potentially hemolytic stress with lypemic plasma effecting lower "protection" from induced hemolysis than essentially fatty-acid free plasma. This effect was less dependent on incubation than on fatty-acid presence during stressing. The reduced propensity for hemolysis afforded by plasma proteins also depended markedly on the speed of the bead, potentially reflecting changes from a predominantly Von Karman trail at lower frequencies to an increasingly disorganized turbulent wake at higher frequencies.

Assessment of new cationic porphyrin binding to plasma proteins by planar microarray and spectroscopic methods

Porphyrins have a unique aromatic structure determining particular photochemical properties that make them promising photosensitizers for anticancer therapy. Previously, we synthesized a set of artificial porphyrins by modifying side-chain functional groups and introducing different metals into the core structure. Here, we have performed a comparative study of the binding properties of 29 cationic porphyrins with plasma proteins by using microarray and spectroscopic approaches. The porphyrins were noncovalently immobilized onto hydrogel-covered glass slides and probed to bio-conjugated human and bovine serum albumins, as well as to human hemoglobin. The signal detection was carried out at the near-infrared fluorescence wavelength (800 nm) that enabled the effect of intrinsic visible wavelength fluorescence emitted by the porphyrins tested to be discarded. Competition assays on porphyrin microarrays indicated that long-chain fatty acids (FAs) (palmitic and stearic acids) decrease porphyrin binding to both serum albumin and hemoglobin. The binding affinity of different types of cationic porphyrins for plasma proteins was quantitatively assessed in the absence and presence of FAs by fluorescent and absorption spectroscopy. Molecular docking analysis confirmed results that new porphyrins and long-chain FAs compete for the common binding site FA1 in human serum albumin and meso-substituted functional groups in porphyrins play major role in the modulation of conformational rearrangements of the protein.

Isotherm and kinetic models and cell surface analysis for determination of the mechanism of metal sorption by Aspergillus versicolor

The isolate Aspergillus versicolor was obtained from an estuary, which is exposed to metal contamination. It was found to have a good metal tolerance and sorption capacity. Further studies revealed that the rate of metal removal from solution is very rapid in the first 5-10 min, and is favoured by a pH of 6.0. The biosorption data obtained was explained by the Freundlich adsorption isotherm model and followed a pseudo-second order kinetics reaction. The fungus showed a higher accumulation of fatty acids when grown in presence of metals as compared to the mycelium grown in absence of the metal; there was also an increase in the saturation index of fatty acids in presence of Cu(2+) which serves as a protective mechanism for the fungus. Fourier Transform Infrared, scanning electron microscopy and EDAX analysis indicated that metal removal from solution by A. versicolor occurred by a passive adsorption to the fungal cell surface, involving an ion exchange mechanism.

Fatty Acids Derived from Royal Jelly Are Modulators of Estrogen Receptor Functions

Royal jelly (RJ) excreted by honeybees and used as a nutritional and medicinal agent has estrogen-like effects, yet the compounds mediating these effects remain unidentified. The possible effects of three RJ fatty acids (FAs) (10-hydroxy-2-decenoic-10H2DA, 3,10-dihydroxydecanoic-3,10DDA, sebacic acid-SA) on estrogen signaling was investigated in various cellular systems. In MCF-7 cells, FAs, in absence of estradiol (E2), modulated the estrogen receptor (ER) recruitment to the pS2 promoter and pS2 mRNA levels via only ERβ but not ERα, while in presence of E2 FAs modulated both ERβ and ERα. Moreover, in presence of FAs, the E2-induced recruitment of the EAB1 co-activator peptide to ERα is masked and the E2-induced estrogen response element (ERE)-mediated transactivation is inhibited. In HeLa cells, in absence of E2, FAs inhibited the ERE-mediated transactivation by ERβ but not ERα, while in presence of E2, FAs inhibited ERE-activity by both ERβ and ERα. Molecular modeling revealed favorable binding of FAs to ERα at the co-activator-binding site, while binding assays showed that FAs did not bind to the ligand-binding pocket of ERα or ERβ. In KS483 osteoblasts, FAs, like E2, induced mineralization via an ER-dependent way. Our data propose a possible molecular mechanism for the estrogenic activities of RJ's components which, although structurally entirely different from E2, mediate estrogen signaling, at least in part, by modulating the recruitment of ERα, ERβ and co-activators to target genes.

Molecular thermodynamics of biodiesel fuel compounds

Biodiesel fuel is a biodegradable clean energetic resource comprised by a mixture of monoalkyl esters of long chain fatty acids that can be obtained from a wide variety of raw materials. In terms of sulfur content, flash point, aromatic content, biodegradability and low emission of greenhouse-gases effect, biodiesel fuel is better than diesel fuel. In this paper we present a molecular-thermodynamic modeling of the phase equilibria of three very common long-chain alkylesters biodiesel compounds: methyl cis-9-octadecenoate (methyl oleate), methyl hexadecanoate (methyl palmitate) and methyl cis,cis,cis-9,12,15-octadecatrienoate (methyl linolenate). For all the cases, molecules are represented as chains of spherical segments that can associate due to the presence of short-ranged attractive sites. These attractive sites as well as the intermolecular interaction between monomer segments are modeled via square-well potentials of variable range (SW), following the Statistical Associating Fluid Theory for Potentials of Variable Range (SAFT-VR; A. Gil-Villegas, A. Galindo, P.J. Whitehead, S.J. Mills, G. Jackson, A.N. Burgess, J. Chem. Phys. 106(1997)4168–4186). The optimized values of the parameters for each pure component are obtained by fitting to vapor pressure and saturated liquid densities data, derived from the empirical Helmholtz free-energy reported recently by Huber et al. (M.L. Huber, E.W. Lemmon, A. Kazakov, L.S. Ott, T.J. Bruno, Energy Fuels 23(2009)3790–3797). Predictions are improved by the use of a discrete potential, instead of a SW potential, to represent segment–segment interactions, that can be tuned to give an optimized description of the liquid–vapor coexistence properties. The results obtained can be used to model reacting systems to produce biodiesel, based on esterification of fatty acids in presence of acid catalyst or on the transesterification with basic catalyst.

KIMIA OKSIGEN SINGLET: SENSITISER, CAHAYA DAN REAKTIVITASNYA TERHADAP ASAM LEMAK TAK JENUH

Singlet oxygen chemistry and photooxidation reaction, in general, often require one or more criticalreaction steps that involve a sensitizer and light for photochemistry production of singlet oxygen from atriplet state. Singlet oxygen can be formed chemically, enzimatically, and photochemically. However, themost well documented formation mechanism for singlet oxygen is photochemistry using sensitizers.Chlorophyll, riboflavin, myoglobin, porphyrins, erythrosine, rose bengal, methylene blue, bilirubin andretinal are well-known photosensitizer and can absorb energy from light and transfer it to triplet oxygen toform singlet oxygen. Photooxidation provides an important way to produced hydroperoxides fromunsaturated fatty acids in presence of oxygen, light energy and photosensitizer. Hydroperoxide are themajor initiation products of lipid oxidation chain reactions. Singlet oxygen participated in the initiation stepof oil oxidation and the reaction rate of singlet oxygen with oleic, linoleic acid and linolenic are about30.000, 1450 and 900 times greater than that of triplet oxygen. Therefore, this review discusses twoimportant singlet oxygen mechanisms, the formation of singlet oxygen and double bond reaction inunsaturated fatty acid system Key word: Singlet oxygen, sensitizer, unsaturated fatty acids, hydroperoxides

Effect of fatty acids, water composition and pH on the wettability alteration of calcite surface

Fatty acids in presence of water film alter calcite surface to oil-wet. The wettability alteration is dependent on the structure of the fatty acids, water composition and pH. Long chain fatty acid (stearic acid), strongly adsorbs onto the calcite surface from “oil phase” ( n-C 10) in oil/water/calcite system as indicated by contact angle measurements. On the other hand, short chain fatty acid (heptanoic acid) adsorbs on the calcite surface to a lesser extent, which agrees with “Traube's rule”. Adsorption of carboxylate anion is influenced by the ionic composition of the water, ionic strength and pH. The presence of Mg 2+ and SO 4 2− ions is shown to increase the water-wetness of the calcite. The degree of wetting is dependent on the pH. At pH < 7 in stearic acid/ n-decane/water/calcite system, both ions reduce the contact angle. Higher reduction is obtained in presence of SO 4 2− compared to Mg 2+. The measured advancing contact angles are 95°, 108° at pH 5 and 88°, 82° at pH 7 in presence of SO 4 2− and Mg 2+, respectively. Further increase of the pH in the presence of Mg 2+ causes more reduction of contact angle (68° at pH 10); while in the presence of SO 4 2− ions an inflection point occurred where the advancing contact angle increased to 100°. In other words, the calcite surface became slightly more oil-wet.

Upregulation of rat P23 (a member of the YjgF protein family) by fasting, glucose diet and fatty acid feeding

In a previous study, we identified and purified a 99-amino-acid rat liver-kidney perchloric-acid-soluble 23-kDa protein (P23) which displays 30% identity with a highly conserved domain of heat shock proteins (HSPs), as well as an AT-rich 3' untranslated region, which has also been described to play a role in H70 mRNA life span and protein expression. An identical perchloric-acid-soluble protein inhibiting protein synthesis in a rabbit reticulocyte lysate system was also found 2 years later by another group. More recently, the novel, the YjgF, protein family has been described, comprising, 24 full-length homologues, including P23, highly conserved through evolution, and consisting of approximately 130 residues each and sharing a common ternary structure. Independent studies from different laboratories have provided various hypothetical functions for each of these proteins. The high degree of evolutionary conservation may suggest that these proteins play an important role in cellular regulation. Although the function of none of these proteins is known precisely, we present experimental evidence which, combined with the relationship to glucose-regulating protein revealed here, and the relationship to fatty-acid-binding protein revealed by others, allow us to propose a role for P23. In rat liver, P23 expression is developmentally regulated and modulated by dietary glucose, and its mRNA is induced by starvation, in the presence of fatty-acids and in 3-MeDAB-induced hepatomas. The mRNA encoding mouse liver P23 is also hormonally modulated in a mouse line AT1F8. These data indicate that P23 protein might be a key controller of intermediary metabolism during fasting.