Fatty Alcohols

Project ID

2760

Category

OPPT

Added on

Oct. 23, 2018, 8:28 a.m.

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Journal Article

Abstract  Three compounds have been identified in the abdominal tip extracts from the female leopard moth,Zeuzera pyrina L. Gas-liquid chromatography and mass spectroscopy data showed that (E, Z)-2, 13-octadecadien-1-ol acetate was the main component and that (Z)-13-octadecen-1-ol acetate and octadecan-1-ol acetate were secondary components. The electroanten-nographic responses of maleZ. pyrina to nanogram amounts of all four 2, 13-octadecadien-1-ol acetate isomers indicated that theE, Z isomer had the maximum activity. A strong EAG response was also recorded for (Z)-7-do-decen-1-ol acetate, which was not detected in the female extracts.

Journal Article

Abstract  A simultaneous extraction-stripping process is proposed for separating volatile products from fermentation broths, it is based on pervaporation through a liquid membrane supported with a hydrophobic porous membrane. The liquid membrane prepared with oleyl alcohol was selected as the most suitable for separating volatile products resulting from acetone-butanol fermentation. The separation performance and stability of the oleyl alcohol liquid membrane were investigated by using dilute aqueous butanol and acetone solutions. The oleyl alcohol liquid membrane was found to be superior by far in both selectivity and permeability of butanol to the better known silicone rubber membrane in its high selectivity for alcohols. Using the oleyl alcohol liquid membrane, the dilute aqueous butanol solutions of around 4 g/L obtained in acetone-butanol fermentation could be concentrated up to 100 times. The stability of this liquid membrane was also quite good as long as the surface tension of the feed solution was less than the critical surface tension of the support membrane. No change in the separation performance was found after the continuous usage in a long period of 100 h.

Journal Article

Abstract  Ethanolamine plasmalogen radiolabelled mainly in the O-alkenyl moiety was prepared from cell suspension cultures of the flagellate Leishmania donovani previously incubated with [1-14C]octadecanol over one growth period. The optimal concentration of [1-14C]octadecanol for labelling was shown to be 1 microM, when 60% of total lipid radioactivity appeared in the 1,2-diradyl-sn-glycero-3-phosphoethanolamine fraction, with an overall yield of approx. 35%. Analysis of this fraction revealed that 93% of the label was present in O-octa-dec-1-enyl, 3% in O-alkyl and 4% in acyl moieties. A specific radioactivity of approx. 14 mCi/mmol was determined. Raising the culture medium concentration of [1-14C]octadecanol to 2 microM yielded a product with a specific radioactivity of 25 mCi/mmol.

Journal Article

Abstract  After growth and experimental conditions were established, the mycolic acid cleavage products, constituent fatty acids, and alcohols of representative strains of Mycobacterium tuberculosis, M. smegmatis, M. fortuitum complex, M. kansasii, M. gordonae, and M. avium complex were determined by capillary gas chromatography. Reproducible cleavage of mycolic acid methyl esters to tetracosanoic (24:0) or hexacosanoic (26:0) acid methyl esters was achieved by heating the sample in a high-temperature muffle furnace. The major constituent fatty acids in all species were hexadecanoic (16:0) and octadecenoic (18:1 omega 9-c, oleic) acids. With the exception of M. gordonae, 10-methyloctadecanoic acid was found in all species; moreover, M. gordonae was the only species tested which contained 2-methyltetradecanoic acid. M. kansasii was characterized by the presence of 2,4-dimethyltetradecanoic acid, M. avium complex by 2-eicosanol, and M. tuberculosis by 26:0 mycolic acid cleavage product. The mycolic acid cleavage product in the other five species tested was 24:0. Although a limited number of strains and species were tested, preliminary results indicate that this gas chromatographic method can be used to characterize mycobacterial cultures by their mycolic acid cleavage products and constituent fatty acid and alcohol content.

Journal Article

Abstract  Synopsis The ternary mixtures investigated were obtained from water, mineral oil and ether-linked non-ionic surfactants (polyoxyethylene derivatives of oleic alcohol). The examination of the rheological properties of these mixtures, particularly the viscoelastic properties of the various phases encountered in these diagrams, was expanded. The phases examined were: - anisotropic paracrystalline phases: hexagonal phase and lamellar phase; - the isotropic paracrystalline phase: type I viscous isotropic phase. The measurement instrument used for this work was a creep rheometer. The paracrystalline phases were subjected to very low shear stresses, and the strains induced were recorded as a function of time. The analysis of creep functions obtained enabled us to construct a viscoelastic model and obtain the value of its parameters for each particular case. This analysis of the viscoelastic properties provides an accurate identification of each of the paracrystalline phases: the lamellar and isotropic viscous phases show respectively a Newtonian fluid nature with a yield value (Bingham model), and a perfect elastic solid. The hexagonal phase on the other hand shows an intermediate type of behaviour which is characterized by a well-defined retarded elasticity. This study could also lead to a microscopic interpretation of their structure.

Journal Article

Abstract  Oxyethylene docosanol (OED) retarded evaporation of agar media in petri plates when the plates were used in an air sampler; this confirmed the report of May (2). Flooding of plates with OED solutions or incorporation of OED into agar media, however, did not alter evaporation rates when the plates were stored in incubators or were refrigerated.

Journal Article

Abstract  Twenty-nine strains of chromogenic mycobacteria belonging to the species Mycobacterium aurum (5 strains), M. duvalii (2), M. flavescens (1), M. gordonae (6), M. kansasii (3), M. obuense (1), M. parafortuitum (3), M. phlei (2), M. rhodesiae (1), M. vaccae (2) and Mycobacterium spp. (3) were studied for fatty acid composition and mycolic acid patterns by gas-liquid chromatography and thin-layer chromatography respectively. Fatty acids found ranged from those with 12-24 carbon atoms and were saturated and monounsaturated straight chain fatty acids, along with 10-methyl branched of 16, 17 and 18 (tuberculostearic acid) carbon atoms. Moreover, 2-methyl tetradecanoic acid was found in M. gordonae, M. kansasii and Mycobacterium spp. (2 strains), and 2,4-dimethyl tetradecanoic acid in M. kansasii and Mycobacterium spp. (2 strains). Nonadecenoic acid was found only in M. flavescens and tuberculostearic acid was not detected in M. gordonae. Three patterns of mycolic acids were obtained: the first, found in M. aurum, M. flavescens, M. phlei, M. rhodesiae and Mycobacterium spp. (1 strain), was characterized by the presence of several spots assigned to alpha-mycolates, keto-mycolates and wax-ester mycolates (omega-carboxy-mycolates and 2-eicosanol and related alcohols); the second, found in M. duvalii, M. obuense, M. parafortuitum and M. vaccae was similar to the first, but it contained an additional spot of alpha'-mycolates; the third pattern, found in M. gordonae, M. kansasii and Mycobacterium spp. (2 strains) contained three spots considered to be alpha-mycolates, methoxy-mycolates and keto-mycolates. The results obtained confirm previously reported data on the fatty and mycolic acid composition of the species studied.

Journal Article

Abstract  Column chromatography of the pentane extract of freeze-dried cotton buds or anthers yielded a wax-sterol ester fraction that exhibited potent feeding stimulant activity for the cotton boll weevil. The waxes of the wax-sterol ester mixture were responsible for the feeding activity. Saponification of the wax-sterol ester fraction yielded about 15% alcohols and 85% sterols. A C18∶1 alcohol, dihydrophytol, phytol, and geranylgeraniol constituted 15, 36, 26, and 23%, respectively, of the total alcohols, implicating certain of their long-chain esters as feeding stimulants. Several esters of dihydrophytol, phytol, and geranylgeraniol were identified among the waxes by GC-MS. Certain phytol, geranylgeraniol, and oleyl alcohol esters containing C12 to C26 acid moieties were synthesized and were found to induce high feeding stimulant activity in the cotton boll weevil.

DOI
Journal Article

Abstract  Objectives. Pretreatment with oral tadenan (TAD) has been shown to possess a protective effect on bladder dysfunction-induced obstruction. We evaluated the functional influence of cotreatment and post-treatment with oral TAD on the frequency/volume characteristics of micturition of conscious rats stimulated with exogenous dihydrotestosterone (DHT) to induce experimental prostate growth.

Methods. Studies were done on 36 adult Sprague-Dawley male rats, treated daily for 6 weeks and grouped as follows: group 1, sesame oil during weeks 1 and 2, peanut oil during weeks 3 to 6; group 2, DHT (1.25 mg/kg subcutaneously) dissolved in sesame oil as vehicle during weeks 1 and 2 and peanut oil during weeks 3 to 6; group 3, DHT (1.25 mg/kg subcutaneously) dissolved in sesame oil as vehicle and TAD (100 mg/kg orally) in peanut oil during weeks I and 2 and TAD during weeks 3 to 6; and group 4, DHT in sesame oil during weeks 1 and 2 and TAD in peanut oil during weeks 3 to 6. The characteristics of frequency/volume were monitored biweekly and at the sixth week.

Results. Controls showed no significant changes from baseline values in volume or frequency during the entire study period. DHT treatment produced a significant increase in frequency (1.9 +/- 0.3 to 3.0 +/- 0.4/hr) and a significant decrease in volume (1.8 +/- 0.3 to 1.2 +/- 0.1 mL). In groups 3 and 4, no significant changes occurred in frequency or volume. By the sixth week of observation, the effects of DHT treatment decreased to control values in all groups. A significant increase in prostatic weight (1191 +/- 11 to 1434 +/- 17 mg/kg) was produced by DHT treatment and TAD cotreatment suppressed growth to 1390 +/- 8.4 mg/kg.

Conclusions. TAD cotreatment or post-treatment suppressed the effects of DHT on micturition, and TAD cotreatment regressed a developing increase in prostatic weight. Post-treatment TAD administration did not reduce already established growth.

Journal Article

Abstract  Mass spectrometry has become an indispensable tool for the global study of metabolites (metabolomics), primarily using electrospray ionization mass spectrometry (ESI-MS). However, many important classes of molecules such as neutral lipids do not ionize well by ESI and go undetected. Chemical derivatization of metabolites can enhance ionization for increased sensitivity and metabolomic coverage. Here we describe the use of tris(2,4,6,-trimethoxyphenyl)phosphonium acetic acid (TMPP-AA) to improve liquid chromatography (LC)/ESI-MS detection of hydroxylated metabolites (i.e. lipids) from serum extracts. Cholesterol which is not normally detected from serum using ESI is observed with attomole sensitivity. This approach was applied to identify four endogenous lipids (hexadecanoyl-sn-glycerol, dihydrotachysterol, octadecanol, and alpha-tocopherol) from human serum. Overall, this approach extends the types of metabolites which can be detected using standard ESI-MS instrumentation and demonstrates the potential for targeted metabolomics analysis.

WoS
Journal Article

Abstract  After patch testing of several groups of patients we analyzed the development of contact allergy to wool wax alcohols and emulsifying fatty alcohols in the last years. For identifying the allergens we used high purified n-alcanols of the chain length of C-8 to C20, lanosterol and aliphatic diols. We found no reaction to cetyl and stearyl alcohol at all - the main allergens in literature. Most of the patch test reactions were caused by n-alcanols of C10H21OH to C15H31OH, but also by lanosterol and aliphatic diols. Alcohols of the chain length C-12 and C-14 we found in all gaschromatographically analyzed samples. Therefore we like to propose allergenfree emulgators for patients on risk.

Journal Article

Abstract  The MCF-7 cell line (human breast epithelial cells) accumulates fatty alcohols. The fatty alcohols were identified as C16:0, C18:0, and C18:1 alcohols by thin-layer chromatography and gas chromatography/mass spectrometry. This accumulation of alcohols in MCF-7 was found in cultures of MCF-7 cells obtained from other laboratories but not in a variety of unrelated cell lines. The presence of the alcohols suggested an aberrant ether lipid metabolism in the MCF-7 cells. Therefore, the capacity for either lipid biosynthesis was evaluated using cells incubated with either [14C]stearyl alcohol or [14C]stearic acid. MCF-7 cells incorporated less than 0.4% of the [14C]alcohol into ether-linked phospholipids, whereas the AB589 breast epithelial cells, used as a "normal control" for comparisons, did not accumulate fatty alcohol and incorporated approximately 20% of the radiolabeled alcohol into phospholipids containing ether linkages. Although the MCF-7 cells were unable to effectively incorporate the fatty alcohol into ether linkages, the cells were able to oxidize the alcohol to fatty acid. When incubated with [14C]stearic acid, the conversion to radiolabeled fatty alcohol in MCF-7 cells was approximately four times higher than the alcohol levels found in AB589 cells. While deficient in the ability to synthesize ether linkages, the MCF-7 cells did incorporate radiolabeled hexadecylglycerol, a precursor containing an ether linkage, into phospholipids. Collectively, the data indicate that the MCF-7 cells possess a deficiency in the alkyl DHAP synthase activity. A near absence of ether-linked lipids in the MCF-7 cells was indicated by the radiolabeling studies, and this finding was corroborated by results from HPLC analysis. Analyses of the partial glycerides, obtained from the enzymatic hydrolysis of cellular phospholipids, found only trace levels of ether lipids in the MCF-7 cells. The aberration in ether lipid biosynthesis did not correlate with the expression of the multidrug resistance phenotype in a series multidrug resistant MCF-7 variants. The results are discussed relative to the use of the MCF-7 cells as a model for investigations of ether lipid biosynthesis and the cellular physiology of ether lipids.

Book/Book Chapter

Abstract  Bladder dysfunction secondary to benign prostatic hyperplasia (BPH) is a major affliction of aging men. BPH can initiate both irritative lower urinary tract symptoms (urgency, frequency, and nocturia), and obstructive symptoms (reduced flow rate, increased micturition pressure, increased duration of micturition, and incomplete emptying). Although these symptoms are related to the effect of the enlarging prostate and subsequent urethral obstruction, there appears to be no direct relationship between prostate size or composition and severity of symptoms.3,13,17,19,23 In addition, the results of standard urodynamic evaluations do not correlate well with the severity of patient symptoms; standard urodynamics cannot accurately predict either level of bladder pathology or potential for recovery following surgery.3,13,17,19,23 One major problem is that current methods of urodynamic analysis, including pressure measurements, are indirect assessments of detrusor power or contractile function.

DOI
Journal Article

Abstract  A new oxyneolignan (rel-(7 alpha,8 beta)-3-methoxy-4',7-epoxy-8,3'-oxyneolignan-4,9,9'-triol) with a scarce C(7)-O-C(4') and C(8)-O-C(3') epoxy linkage, along with eight known compounds, abieta-8,11,13-triene, sandaracopimara-8(14), 15-diene, 6,7-dehydroferruginol methyl ether, 18-hydroxydehydroabietane, sandaracopimara-8(14), 15-dien-18-ol, docosanol, sugiol and palmitic acid, were isolated from the chloroform-soluble fraction of the acetone extract from Juniperus brevifolia leaves. Their structures were established on the basis of the spectral evidences and direct comparison with values from literature data. (C) 2010 Phytochemical Society of Europe. Published by Elsevier B.V. All rights reserved.

DOI
Journal Article

Abstract  The ATPase activity of the (Ca2+-Mg2+)-ATPase purified from skeletal muscle sarcoplasmic reticulum and reconstituted into phosphatidylcholine bilayers of defined composition depends on the fatty acyl chain length of the surrounding phospholipid. The stoichiometry of Ca2+ binding to the ATPase is also sensitive to fatty acyl chain length, changing from the normal two Ca2+ ions bound per ATPase molecule to one Ca2+ ion bound for the ATPase reconstituted with phosphatidylcholines of chain lengths C12, C14, or C24. For the ATPase reconstituted with mixtures of phosphatidylcholines where one phosphatidylcholine supports a Ca2+ binding stoichiometry of two and the other a stoichiometry of one, a highly cooperative change in binding stoichiometry with change in phospholipid composition is observed, suggesting that the effects of phospholipids follow from binding to a large number of sites at the lipid-protein interface of the ATPase. For the ATPase reconstituted with either 1-myristoyl-2-oleoylphosphatidylcholine or 1-oleoyl-2-myristoylphosphatidylcholine, the stoichiometry of Ca2+ binding is the normal two per ATPase molecule. Effects of short-chain phosphatidylcholines on Ca2+ binding stoichiometry and on ATPase activity can be reversed by addition of androstenol, oleic acid, methyl oleate, or oleyl alcohol but these molecules have no effect on the ATPase reconstituted with dinervonylphosphatidylcholine (C24:1). For the ATPase reconstituted with phosphatidylcholines with chain lengths between C16 and C22, release of the two bound Ca2+ ions is sequential, with release of the second Ca2+ being inhibited by high concentrations of Ca2+ in the bathing medium. For the ATPase reconstituted with phosphatidylcholines of chain lengths C14 or C24, release of the single bound Ca2+ is only slightly inhibited by the presence of Ca2+ in the medium. For the ATPase reconstituted with phosphatidylcholines of chain lengths between C16 and C24, removal of bound Ca2+ results in a decrease in tryptophan fluorescence intensity, whereas for the ATPase reconstituted with phosphatidylcholines of chain lengths C12 or C14, removal of bound Ca2+ results in an increase in tryptophan fluorescence intensity. In mixtures of phosphatidylcholines, changes in the tryptophan response mirror changes in Ca2+ binding stoichiometry.

DOI
Journal Article

Abstract  Mitotic checkpoint impairment is present in human lung cancers with chromosomal instability (CIN). Spindle-checkpoint genes have been reported to be mutated in several human cancers; but these mutations are infrequent. Recent reports suggest that the hBUBR1 gene may play an important role in mitotic checkpoint control and in mitotic checkpoint impairment in human cancers. We analyzed the expression of hBUBR1 in lung cancer cell lines using real time quantitative RT-PCR. The expression of BUBR1 was found to be up-regulated in all of these cell lines. In addition, we cloned and characterized the promotor region of hBUBR1 and determined its genomic structure, which includes 23 exons. The open reading frame (ORF) of the hBUBR1 gene comprises exons 1 through 23. There are GC-rich regions located at the flanking region and about 150 bp upstream from exon 1. The promoter region (424 bp upstream from exon 1) showed promoter activity and includes multiple transcription factor consensus binding motifs, including those for Sp1, Nkx-2, CdxA, SRY, MyoD, Ik-2, HNF-3b, Staf, Oct-1, Nkx-2, v-Myb, and AML 1a. Multiple pathways leading to activation of those binding factors may contribute to hBUBR1 gene transcription. Knowledge of the genomic structure and the promoter region of the hBUBR1 gene will facilitate investigation of its role in mitotic checkpoint control and tumor progression in human cancers. (C) 2002 Elsevier Science Ireland Ltd. All rights reserved.

DOI
Journal Article

Abstract  The autumn gum moth, Mnesampela privata (Guenee) (Lepidoptera: Geometridae), is native to Australia and can be a pest of plantation eucalypts. Field-collected and laboratory-reared female autumn gum moths were dissected to remove glands likely to contain components of the sex pheromone. Using gas chromatography (GC) and combined gas chromatography-mass spectrometry (GC-MS), three compounds were identified from female extracts, namely (3Z,6Z,9Z)-3,6,9-nonadecatriene, 1-hexadecanol and 1-octadecanol (confirmed by comparison with synthetic samples). Nonadecatriene elicited an antennal response in male autumn gum moth during gas chromatographic analyses combined with electroantennographic detection (GC-EAD). In electroantennogram (EAG) recording male M. privata antennae responded to the nonadecatriene. Nonadecatriene was synthesised via Kolbe electrolysis, starting with (9Z,12Z,15Z)-octadeca-9,12,15-trienoic acid (linolenic acid) and propanoic acid or via an alternative four-step method also starting from linolenic acid. In field trials (3Z,6Z,9Z)-3,6,9-nonadecatriene proved attractive to male moths. Thus, we conclude that (3Z,6Z,9Z)-3,6,9-nonadecatriene is a sex pheromone component of autumn gum moth. This component has been identified in extracts from other geometrids in the same subfamily, Ennominae. However, to our knowledge this is the first example where (3Z,6Z,9Z)-3,6,9-nonadecatriene has been found in females and also proved attractive to male moths when presented on its own. Our results are discussed in relation to other geometrid pheromones.

WoS
Journal Article

Abstract  Sjogren-Larsson syndrome (SLS) is an inherited disorder associated with deficient oxidation of long-chain aliphatic alcohols. Previous studies have reported modest elevations in total (free + esterified) fatty alcohols in SLS, but free fatty alcohols have not been selectively measured, in part because of their low concentrations in most tissues and the presence of trace fatty alcohol contaminants in some solvents used for their analysis. We adapted methods to measure free fatty alcohols in cultured cells and plasma that minimize exogenous alcohol contamination. Fatty alcohols were analyzed as acetate derivatives, using capillary column gas chromatography. By this method, cultured skin fibroblasts from SLS patients were found to have 7- and 8-fold elevations in the mean content of hexadecanol (16:0-OH) and octadecanol (18:0-OH), respectively. The mean plasma 16:0-OH and 18:0-OH concentrations in SLS patients (n = 11) were 9- and 22-fold higher than in normal controls, respectively. In SLS fibroblasts, most of the fatty alcohol (59%) that accumulated was free rather than esterified alcohol, whereas free alcohol accounted for 23% of the total alcohol in normal cells. These results indicate that elevations in free fatty alcohols provide a sensitive marker for the enzymatic defect in SLS. The ability to measure free fatty alcohols in cultured cells and plasma should prove useful for investigations of normal fatty alcohol metabolism and the deranged metabolism in SLS.

Journal Article

Abstract  Human prostate was used as a source of 5 alpha reductase. Compounds were incubated with an enzyme preparation and [3H]testosterone. [3H]-dihydrotestosterone production was measured to calculate 5 alpha reductase activity. IC50 values (ng/ml) were finasteride = 1; Permixon = 5,600; Talso = 7,000; Strogen Forte = 31,000; Prostagutt = 40,000; and Tadenan = 63,000. Bazoton and Harzol had no activity at concentrations up to 500,000 ng/ml. In castrate rats stimulated with testosterone (T) or dihydrotestosterone (DHT), finasteride, but not Permixon or Bazoton, inhibited T stimulated prostate growth, while none of the three compounds inhibited DHT stimulated growth. These results demonstrate that finasteride inhibits 5 alpha reductase, while Permixon and Bazoton have neither anti-androgen nor 5 alpha reductase inhibitory activity. In addition, in a 7 day human clinical trial, finasteride, but not Permixon or placebo, decreased serum DHT in men, further confirming the lack of 5 alpha reductase inhibition by Permixon. Finasteride and the plant extracts listed above do not inhibit the binding of DHT to the rat prostatic androgen receptor (concentrations to 100 micrograms/ml). Based on these results, it is unlikely that these plant extracts would shrink the prostate by inhibiting androgen action or 5 alpha reductase.

WoS
Journal Article

Abstract  The hydrogenation of methyl oleate (methyl 9Z-octadecenoate) into oleyl alcohol (9Z-octadecen-1-ol) is carried out in an autoclave at 8.0 MPa and 543 K with Ru-Sn catalysts. The activity and the selectivity of this catalytic system are linked to the preparation method, the nature of the support (alumina, silica, active carbon and zinc oxide) and to the tin content. Selectivities of 50 and 55% to unsaturated alcohol respectively were obtained with a Ru-Sn-B/alumina catalyst resulting from the co-reduction of metallic salts by sodium borohydride and a Ru-Sn/alumina catalyst prepared by a sol-gel method. Our work also showed that a previously unreported transesterification reaction between methyl oleate and oleyl alcohol occurred rapidly and led to a 'higher' ester (oleyl oleate). This side-reaction significantly decreases the selectivity to unsaturated alcohol. Nevertheless, at higher conversion the oleyl oleate is gradually hydrogenated into oleyl alcohol.

Journal Article

Abstract  The conjugation of siRNA to molecules, which can be internalized into the cell via natural transport mechanisms, can result in the enhancement of siRNA cellular uptake. Herein, the carrier-free cellular uptake of nuclease-resistant anti-MDR1 siRNA equipped with lipophilic residues (cholesterol, lithocholic acid, oleyl alcohol and litocholic acid oleylamide) attached to the 5'-end of the sense strand via oligomethylene linker of various length was investigated. A convenient combination of H-phosphonate and phosphoramidite methods was developed for the synthesis of 5'-lipophilic conjugates of siRNAs. It was found that lipophilic siRNA are able to effectively penetrate into HEK293, HepG2 and KB-8-5 cancer cells when used in a micromolar concentration range. The efficiency of the uptake is dependent upon the type of lipophilic moiety, the length of the linker between the moiety and the siRNA and cell type. Among all the conjugates tested, the cholesterol-conjugated siRNAs with linkers containing from 6 to 10 carbon atoms demonstrate the optimal uptake and gene silencing properties: the shortening of the linker reduces the efficiency of the cellular uptake of siRNA conjugates, whereas the lengthening of the linker facilitates the uptake but retards the gene silencing effect and decreases the efficiency of the silencing.

WoS
Journal Article

Abstract  Recovery of metabolites from fermentation broth by solvent extraction can be used to optimize fermentation processes. End-product reutilization, low product concentration and large volumes of fermentation broth and the requirements for large bioreactors, in addition to the high cost largely contributed to the decline in fermentative 2,3-butanediol production. Extraction can successfully be used for in-situ alcohol recovery in 2,3-butanediol fermentations to increase the substrate conversion. In the present work organic extraction of 2,3-butanediol produced by Klebsiella pneumoniae fermentation was studied to determine solvent effect on 2,3-butanediol production. The aim of this project was liquid-liquid extractive fermentation systems evaluation as an alternative to overcome the end product effect and to increase of 2,3-butanediol production by K. pneumoniae because Conventional fermentative production of 2,3-butanediol by K. pneumoniae has the disadvantage of product reutilization by the organism. Alternatives to overcome this problem have met with limited success. Extractive fermentation has been shown to solve this problem. An effort has been made in this study to use for the extractive fermentation of 2,3-butanediol using oleyl alcohol as extract-ant. Eighteen organic solvents were examined to determine their biocompatibility for in situ extraction of fermentation products from cultures of the K. pneumoniae. From 18 tested solvents, 13 of which were non-toxic to K. pneumoniae. The highest 2,3-butanediol production (23.01 g l(-1)) was achieved when oleyl alcohol was used. In situ removal of end products from K. pneumoniae resulted in increased productivity. In conclusion 2, 3-hutanediol productivity increased from 0.5 g l(-1)h(-1) to 0.66 g l(-1)h(-1) in extractive fermentation using oleyl alcohol as the extraction solvent.

DOI
Journal Article

Abstract  In this work, the potential of waxes for preparing with the ultrasonic spray congealing technique microparticles for controlling the in vitro release of verapamil HCl was investigated. The first part of the study encompassed the optimisation of the formulation to achieve an efficient drug incorporation together with a satisfactory in vitro drug release rate. In particular, microcrystalline wax, stearyl alcohol and mixtures of the two were used. Also a surfactant (soya lecithin) was added to the formulations. After the particle size analysis, the characterisation of the microparticles involved the study of the solid state of drug and carriers in the systems (DSC, HSM and XRD) and the morphological and chemical analyses of the microparticle surface (SEM and XPS). Finally, the drug release mechanism from these devices was evaluated using the statistical moment analysis. The results of this study show that by selecting the type and the amount of the carriers, microparticles with a spherical shape and a good encapsulation efficiency were observed. These particles showed a zero-order release for 8 h, without modifying the solid state properties of the drug. Therefore, waxy microparticles prepared by the ultrasonic spray congealing technique are promising solvent-free devices for controlling the release of verapamil HCl. (C) 2003 Elsevier Science B.V. All rights reserved.

Journal Article

Abstract  To better understand the mode of action of Tadenan, a drug used in the treatment of benign prostatic hyperplasia, the effect of its active principle docosanol, IK.2, was investigated in rats. IK.2 had no effects on the weight and histologic appearance of the prostate in intact rats but increased the RNA/DNA quotient in the ventral prostate. The plasma concentrations of luteinizing hormone and testosterone were reduced. In orchiectomized animals IK.2 increased the weight of the prostate and the adrenals. In adrenalectomized, orchiectomized animals IK.2 did not increase prostatic weight but on the contrary caused a further weight reduction. IK.2 had a thymolytic effect in intact rats but not in adrenalectomized rats in which the thymus weight was increased. The results indicate that IK.2 increases adrenal steroid secretion. The supposedly higher concentration of adrenal androgens causes a stimulation of the prostate most easily discernible in orchiectomized animals. The further weight reduction of the ventral prostate in orchiectomized, adrenalectomized animals, and the increased thymus weight in adrenalectomized animals after IK.2 administration may suggest that IK.2 has effects other than the stimulatory effect on the adrenals.

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