Catalogue Search | MBRL
Are you sure you want to remove the book from the shelf?
{{itemTitle}}
46,659
result(s) for
"ESTERS"
Sort by:
Model cellulosic surfaces
\"Molecular interactions of cellulose surfaces govern the three-dimensional assembly of plant cell walls and play important roles in the pulp and paper, textile, and food industries. Interactions of cellulose surfaces with other polysaccharides, proteins, polynucleotides, and mammalian cells are of interest for biomedical cellulose applications and, more recently, interactions of cellulolytic enzymes with cellulosic substrates is of interest in the production of bioethanol from lignocellulosic feedstocks. The study of interactions and sorption phenomena involving cellulose and cellulosic materials requires well-defined model surfaces. Several methods to prepare such model surfaces have been developed over the past fifteen years and an increasing number of cellulose interaction studies involving such model surfaces can be found in the literature.
Book
Identification and Registration of the Novel High-Rhizome-Yielding Variety Bharamputra-1 of IKaempferia galanga/I L
Kaempferia galanga is an endangered plant whose recognition as a flavoring agent and perfumery ingredient has increased its demand greatly. Therefore, the present investigation aimed at the identification of high-rhizome-yielding varieties of K. galanga. A total of forty-nine germplasms were collected from different parts of India and planted at CSIR-NEIST, Jorhat experimental farm, during 2013. The two-year evaluation of essential morphological and chemical data was recorded for the selection of superior rhizomes with a high rhizome yield during 2014 and 2015. Subsequently, multi-location field trials were conducted with the selected elite germplasm along with controls using a randomized complete block design, and relevant morphological traits as well as essential oil quality data were recorded for all the lines for three consecutive years during 2016, 2017 and 2018. The essential oil quality was analyzed by using GC/MS. The data obtained were statistically analyzed for stability based on rhizome yield, essential oil yield and days to maturity. A high-rhizome-yielding variety of K. galanga was identified and named Bharamputra-1.Itwas found to be stable in multi-locational trials conducted in Northeast India. The variety showed a mean rhizome yield of 10.01 tones/ha. Stability parameters, namely, βi = 1.13 and σ[sup.2]di = −0.07 were recorded and found to be superior to those of the other examined varieties. The chemical profiling of the rhizome essential oil of the selected germplasm was also performed using GC/MS, which revealed ethyl p-methoxycinnamate (37.25%), trans-ethyl cinnamate (28.35%), endo-borneol (8.91%), eucalyptol (6.83%), (-)-camphor (3.98%) and 3-carene (3.77%) as the main components. The cultivation of this identified variety could help in the successful commercial cultivation of the crop.
Journal Article
Steady-state bioavailability of prescription omega-3 on a low-fat diet is significantly improved with a free fatty acid formulation compared with an ethyl ester formulation: the ECLIPSE II study
The systemic bioavailability of free fatty acid (FFA) forms of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) compared with ethyl ester (EE) forms is dependent on the presence of intestinal lipases and is highest during consumption of high-fat meals. Given that patients with cardiovascular disease are advised to reduce dietary fat intake, potentially lowering the bioavailability and therapeutic benefit, the hypothesis that FFA forms provide for higher bioavailability compared with EE forms under low-fat diet conditions was tested where the pharmacokinetics of the FFA form (Epanova™) were compared with those of an ethyl ester form (Lovaza®) following repeat dosing. Fifty-two healthy male and female subjects were equally allocated to one of two open-label, parallel-group cohorts. Following a Therapeutic Lifestyle Changes diet for a minimum of 7 days, blood samples were drawn for endogenous values for EPA and DHA over a 24-hour period. Subjects were then administered 4 × 1 g capsules of either Epanova (OM3 FFA) or Lovaza (OM3 EE) once daily for 14 days, following which serial blood samples were drawn over a 24-hour period to characterize the bioavailability of EPA and DHA from the respective formulations. In addition, changes from baseline in lipid profile were explored. Systemic bioavailability, as measured by area under the curve from time zero to 24 hours (AUC(0-τ)) and the maximum measured plasma concentrations during the 0-24 hour dosing interval (C(max,ss)) of unadjusted total plasma EPA + DHA were approximately 3-fold and 3.9-fold higher, respectively, for Epanova relative to Lovaza. Following baseline adjustment, the magnitude of difference in bioavailability was approximately 5.8-fold and 6.5-fold higher in AUC(0-τ) and C(max,ss), respectively, for Epanova relative to Lovaza. Serum triglycerides were reduced by a significantly greater extent (P = 0.013) for Epanova relative to Lovaza (21% versus 8%). The bioavailability of the FFA forms of EPA and DHA in Epanova are significantly greater than the bioavailability from the EE forms present in Lovaza under low-fat dietary conditions normally recommended for patients with cardiovascular disease. This increased bioavailability may lead to improved triglyceride-lowering in patients with hypertriglyceridemia.
Journal Article
Comprehensive Evaluation of the Melting Points of Fatty Acids and Esters Determined by Differential Scanning Calorimetry
The melting point is one of the most important physical properties of a chemical compound and it plays a significant role in determining possible applications. For fatty acid esters the melting point is essential for a variety of food and non-food applications, the latter including biodiesel and its cold-flow properties. In this work, the melting points of fatty acids and esters (methyl, ethyl, propyl, butyl) in the C₈-C₂₄ range were determined by differential scanning calorimetry (DSC), many of which for the first time. Data for triacylglycerols as well as ricinoleic acid and its methyl and ethyl esters were also acquired. For some compounds whose melting points have been previously reported, data discrepancies exist and a comprehensive determination by DSC has not been available. Variations in the present data up to several °C compared to data in prior literature were observed. The melting points of some methyl-branched iso- and anteiso-acids and esters were also determined. Previously unreported systematic effects of compound structure on melting point are presented, including those for ω-9 monounsaturated fatty acids and esters as well as for methyl-branched iso and anteiso fatty acids and esters. The melting point of a pure fatty acid or ester as determined by DSC can vary up to approximately 1 °C. Other thermal data, including heat flow and melting onset temperatures are briefly discussed.
Journal Article
Roles of the αsub.1B-Adrenergic Receptor Phosphorylation Domains in Signaling and Internalization
The function of the α[sub.1B]-adrenergic receptor phosphorylation sites previously detected by mass spectrometry was evaluated by employing mutants, substituting them with non-phosphorylatable amino acids. Substitution of the intracellular loop 3 (IL3) sites did not alter baseline or stimulated receptor phosphorylation, whereas substitution of phosphorylation sites in the carboxyl terminus (Ctail) or both domains (IL3/Ctail) markedly decreased receptor phosphorylation. Cells expressing the IL3 or Ctail receptor mutants exhibited a noradrenaline-induced calcium-maximal response similar to those expressing the wild-type receptor, and a shift to the left in the concentration–response curve to noradrenaline was also noticed. Cells expressing the IL3/Ctail mutant exhibited higher apparent potency and increased maximal response to noradrenaline than those expressing the wild-type receptor. Phorbol ester-induced desensitization of the calcium response to noradrenaline was reduced in cells expressing the IL3 mutant and abolished in cells in which the Ctail or the IL3/Ctail were modified. In contrast, desensitization in response to preincubation with noradrenaline was unaffected in cells expressing the distinct receptor mutants. Noradrenaline-induced ERK phosphorylation was surprisingly increased in cells expressing IL3-modified receptors but not in those expressing receptors with the Ctail or IL3/Ctail substitutions. Our data indicate that phosphorylation sites in the IL3 and Ctail domains mediate and regulate α[sub.1B]-adrenergic receptor function. Phorbol ester-induced desensitization seems to be closely associated with receptor phosphorylation, whereas noradrenaline-induced desensitization likely involves other elements.
Journal Article
Phanerosides A–X, Phenylpropanoid Esters of Sucrose from the Rattans of IPhanera championii/I Benth
Twenty-four new phenylpropanoid esters of sucrose, phanerosides A–X (1–24), were isolated from an EtOH extract of the rattans of Phanera championii Benth. (Fabaceae). Their structures were elucidated on the basis of comprehensive spectroscopic data analysis. A wide range of structural analogues were presented due to the different numbers and positions of acetyl substituents and the structures of phenylpropanoid moieties. Phenylpropanoid esters of sucrose were isolated from the Fabaceae family for the first time. Biologically, the inhibitory effects of compounds 6 and 21 on NO production in LPS-induced BV-2 microglial cells were better than that of the positive control, with IC[sub.50] values of 6.7 and 5.2 μM, respectively. The antioxidant activity assay showed that compounds 5, 15, 17, and 24 displayed moderate DPPH radical scavenging activity, with IC[sub.50] values ranging from 34.9 to 43.9 μM.
Journal Article
Heimionones A–E, New Sesquiterpenoids Produced by IHeimiomyces/I sp., a Basidiomycete Collected in Africa
With heimionones A-E (1-5), five new terpenoids were isolated from submerged cultures of Heimiomyces sp. in addition to the previously described compounds hispidin, hypholomin B, and heimiomycins A and B. Planar structures of the metabolites were elucidated by 1D and 2D NMR in addition to HRESIMS data. While ROESY data assigned relative configurations, absolute configurations were determined by the synthesis of MTPA esters of 1, 3, and 5. The [6.3.0] undecane core structure of compounds 3-5 is of the asteriscane-type, however, the scaffold of 1 and 2 with their bicyclo [5.3.0] decane core and germinal methyl substitution is, to our knowledge, unprecedented. Together with several new compounds that were previously isolated from solid cultures of this strain, Heimiomyces sp. showed an exceptionally high chemical diversity of its secondary metabolite profile.
Journal Article
Excretion Routes of Okadaic Acid and Dinophysistoxin-2 from Mussels
The knowledge of the routes of excretion of the toxins accumulated by molluscs is a key step in designing methods that accelerate depuration. In this work, the excretion route, in mussels and cockles, of the main diarrhetic shellfish poisoning (DSP) toxins in Europe (okadaic acid and dinophysistoxin-2) after natural intoxication were studied. During depuration, the amounts of free toxins and their derivatives were quantified in bivalves, faeces, and water. Most toxins (>98%) were excreted through faeces as acyl derivatives (most likely 7-O-acyl esters), independent of the ratio between these derivatives and free toxins in soft tissues. The small proportion of toxins excreted into water mostly constituted the free forms of the toxins. Both species shared the same route even though they contained very different proportions of free toxins in their soft tissues. No substantial changes in this general pattern were observed during the experiment. The esters of fatty acids with 16 carbon atoms were the most abundant in both soft tissues and faeces, but they were not the same in mussels and cockles. Most of the variability in ester proportions can be attributed to the species more than to their differential excretion (water or faeces) suggesting that there are not large differences in the depuration of the different esters.
Journal Article
Lanostane Triterpenoids and Ergostane Steroids from IGanoderma luteomarginatum/I and Their Cytotoxicity
Macrofungus Ganoderma luteomarginatum is one of the main species of Ganoderma fungi distributed in Hainan province of China, the fruiting bodies of which have been widely used in folk as a healthy food to prevent tumors. To explore the potential cytotoxic constituents from G. luteomarginatum, the phytochemical investigation on the ethyl acetate soluble fraction of 95% ethanolic extract from the fruiting bodies of this fungus led to the isolation of twenty-six lanostane triterpenoids (1–26), including three undescribed ones (1–3), together with eight ergostane steroids (27–34). The structures of three new lanostane triterpenoids were elucidated as lanosta-7,9(11)-dien-3β-acetyloxy-24,25-diol (1), lanosta-7,9(11)-dien-3-oxo-24,26-diol-25-methoxy (2), and lanosta-8,20(22)-dien-3,11,23-trioxo-7β,15β-diol-26-oic acid methyl ester (3) by the analysis of 1D, 2D NMR, and HRESIMS spectroscopic data. All isolates were assayed for their cytotoxic activities using three human cancer cell lines (K562, BEL-7402, and SGC-7901) and seven lanostane triterpenoids (1, 2, 7, 13, 18, 22, and 24), and one ergostane steroid (34) showed definite cytotoxicity with IC[sub.50] values that ranged from 6.64 to 47.63 μg/mL. Among these cytotoxic lanostane triterpenoids, compounds 2 and 13 showed general cytotoxicity against three human cancer cell lines, while compounds 1 and 18 exhibited significant selective cytotoxicity against K562 cells with IC[sub.50] values of 8.59 and 8.82 μg/mL, respectively. Furthermore, the preliminary structure–cytotoxicity relationships was proposed.
Journal Article