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Hydrolysis Products (hydrolysis + products)
Selected AbstractsPhospholipase stimulates lipogenesis in SZ95 sebocytesEXPERIMENTAL DERMATOLOGY, Issue 7 2008S. Schagen Introduction:, With progressing ageing human sebocytes reduce lipid production. However, the influence of certain aging mechanisms on sebaceous lipid synthesis as well as ways to influence the latter is not fully identified. Certain lipids act as ligands of nuclear receptors such as PPAR. Phospholipase (PLA2) catalyzes the hydrolysis of the sn-2 fatty acyl bond of phospholipids to yield free fatty acid and lysophospholipid. It has been hypothesized that PPAR may be activated by hydrolysis products of phospholipids and also by eicosanoids obtained through PLA2 activity. Materials and Methods:, A method to quantify sebaceous lipid synthesis of SZ95 sebocytes in vitro was established and the cells were treated by snake venom Bothrops moojeni gel filtration fractions (Botmo GF). Botmo GF fractions were further purified by RP-HPLC, and a fraction with PLA2 activity (Botmo GF11-117) and a fraction without enzymatic activity (Botmo GF11-101) were identified and additionally tested. Results:, Botmo GF fractions increased lipogenesis in SZ95 sebocytes without inducing apparent toxic or apoptotic effects. Botmo GF11-101 (1 ,g/ml) enhanced neutral lipid synthesis by up to 170% and polar lipid synthesis by up to 120%. The enzymatically active PLA2 Botmo GF11-117 (1 ,g/ml) increased synthesis of neutral lipids by up to 200%, and polar lipids by up to 120% compared to untreated SZ95 sebocytes. Conclusion:, PLA2 activation or suppression could be important for human sebaceous lipogenesis. PLA2 modifiers may be attractive for skin lipid research and pharmacological/cosmetic products. [source] GC,MS analysis of volatile hydrolysis products from glucosinolates in Farsetia aegyptia var. ovalisFLAVOUR AND FRAGRANCE JOURNAL, Issue 2 2003A. A. Al-Gendy Abstract Twenty-two volatile glucosinolate hydrolysis products from seeds and leaves of Farsetia aegyptia var. ovalis were identi,ed and quanti,ed using both natural autolysis and exogenous myrosinase, followed by GC,MS. The 22 isothiocyanate thiocyanate, epithioalkane nitrile and nitrile hydrolysis products identi,ed can be rationalized, assuming 13 glucosinolates in the seeds and 12 in the leaves. Among the volatile hydrolysis products observed, those derived from allylglucosinolates and 3-methylsulphinylpropylglucosinolate (glucoiberin) were prominent. Copyright © 2003 John Wiley & Sons, Ltd. [source] A DFT study on the hydrolysis mechanism of NH-tautomeric antitumors of [HL][trans -RuCl4L(dmso- S)]INTERNATIONAL JOURNAL OF QUANTUM CHEMISTRY, Issue 6 2010Jin Can Chen Abstract The hydrolysis process of Ru (III) complex [Htrz][trans -RuCl4(1- H -1,2,4-triazole)(dmso- S)] 1, a potential antitumor complex similar to the well-known anticancer agent [ImH][trans -RuCl4(Im)(dmso- S)] (NAMI-A), has been investigated by using density functional theory (DFT) method, and the solvent effect was also considered and calculated by conductor-like polarizable calculation model (CPCM). Meanwhile, the hydrolysis process of the NH-tautomeric isomer, [Htrz][trans -RuCl4(4- H -1,2,4-triazole)(dmso- S)] 2, was also modeled and predicted by the same methods. The structural characteristics and the detailed energy profiles for the hydrolysis processes of two isomers have been obtained. The analysis of thermodynamic and kinetic characteristics of hydrolysis reaction suggests the following: for the first hydrolysis step, the Complex 1 has lower hydrolysis rate than the reported anticancer drug NAMI-A, and the result is in accordance with experimental one. However, Complex 1 has obviously higher hydrolysis rate than its isomer Complex 2, and the result was reasonably explained in theory. For the second hydrolysis step, the formation of cis -diaqua species is thermodynamic preferred to that of trans isomers. In addition, the trend in nucleophilic attack abilities (A) of hydrolysis products by pertinent biomolecules was revealed and predicted. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2010 [source] Kinetic Analysis of L -Carnosine Formation by ,-AminopeptidasesADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 2-3 2010Tobias Heck Abstract The ,,,-dipeptide L -carnosine occurs in high concentrations in long-lived innervated mammalian tissues and is widely sold as a food additive. On a large scale L -carnosine is produced by chemical synthesis procedures. We have established two aqueous enzymatic reaction systems for the preparation of L -carnosine using the dissolved bacterial ,-aminopeptidases DmpA from Ochrobactrum anthropi and BapA from Sphingosinicella xenopeptidilytica as catalysts and investigated the kinetics of the enzyme-catalyzed peptide couplings. DmpA catalyzed the formation of L -carnosine from C-terminally activated ,-alanine derivatives (acyl donor) and L -histidine (acyl acceptor) in an aqueous reaction mixture at pH,10 with high catalytic rates (Vmax=19.2,,mol,min,1 per mg of protein, kcat=12.9,s,1), whereas Vmax in the BapA-catalyzed coupling reaction remained below 1.4,,mol,min,1 per mg of protein (kcat=0.87,s,1). Although the equilibrium of this reaction lies on the side of the hydrolysis products, the reaction is under kinetic control and L -carnosine temporarily accumulated to concentrations that correspond to yields of more than 50% with respect to the employed acyl donor. However, competing nucleophiles caused unwanted hydrolysis and coupling reactions that led to decreased product yield and to formation of various peptidic by-products. The substitution of L -histidine for L -histidine methyl ester as acyl acceptor shifted the pKa of the amino functionality from 9.25 to 6.97, which caused a drastic reduction in the amount of coupling by-products in an aqueous reaction system at pH,8. [source] Co-operative actions and degradation analysis of purified xylan-degrading enzymes from Thermomonospora fusca BD25 on oat-spelt xylanJOURNAL OF APPLIED MICROBIOLOGY, Issue 6 2003M. Tuncer Abstract Aims: To determine and quantify the products from the degradation of xylan by a range of purified xylan-degrading enzymes, endoxylanase, , -xylosidase and , - l -arabinofuranosidase produced extracellularly by Thermomonospora fusca BD25. Methods and Results: The amounts of reducing sugars released from oat-spelt xylan by the actions of endoxylanase, , -xylosidase and , - l -arabinofuranosidase were equal to 28·1, 4·6 and 7% hydrolysis (as xylose equivalents) of the substrate used, respectively. However, addition of , -xylosidase and , - l -arabinofuranosidase preparation to endoxylanase significantly enhanced (70 and 20% respectively) the action of endoxylanase on the substrate. The combination of purified endoxylanase, , -xylosidase and , - l -arabinofuranosidase preparations produced a greater sugar yield (58·6% hydrolysis) and enhanced the total reducing sugar yield by around 50%. The main xylooligosaccharide products released using the action of endoxylanase alone on oat-spelt xylan were identified as xylobiose and xylopentose. , - l -Arabinofuranosidase was able to release arabinose and xylobiose from oat-spelt xylan. In the presence of all three purified enzymes the hydrolysis products of oat-spelt xylan were mainly xylose, arabinose and substituted xylotetrose with lesser amount of substituted xylotriose. Conclusions: The addition of the , -xylosidase and , - l -arabinofuranosidase enzymes to purified xylanases more than doubled the degradation of xylan from 28 to 58% of the total substrate with xylose and arabinose being the major sugars produced. Significance and Impact of the Study: The results highlight the role of xylan de-branching enzymes in the degradation of xylan and suggest that the use of enzyme cocktails may significantly improve the hydrolysis of xylan in industrial processes. [source] Improvement of a fed-batch process for high level xylanase production by a Bacillus strainJOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 5 2001Gerhard Schneider Abstract In this paper, the improvement of a fed-batch fermentation from the point of view of an industrial xylanase production process is described. The Bacillus strain chosen for this study is able to produce high quantities of a xylanase that is suitable to be used as bleach boost agent in chlorine-free bleaching sequences of paper pulp. It was found that xylo-oligosaccharides (hydrolysis products from xylan by xylanase action) were indispensable for induction of the enzyme synthesis, but that their presence in quantities of only 0.1,g,dm,3 xylose equivalents led to catabolite repression. A substrate-limited fed-batch process, that is the most adapted, was furthermore improved with regard to nutrient requirement of the microorganism, especially the nitrogen source. A process with constant supply of a culture medium containing xylan, peptone and mineral nitrogen was able to produce 20,240,nkat,cm,3 with a productivity of 910,nkat,cm,3,h,1, which places the process among the best ever reported. © 2001 Society of Chemical Industry [source] Relationships Between Concentrations of Cocaine and Its Hydrolysates in Peripheral Blood, Heart Blood, Vitreous Humor and UrineJOURNAL OF FORENSIC SCIENCES, Issue 2 2006Wayne C. Duer Ph.D. ABSTRACT: Cocaine is known to degrade in vivo and in vitro by several hydrolytic mechanisms. A previous study found that the initial amount of cocaine added to plasma could be accounted for by summing the molar concentrations of cocaine's hydrolysis products and the cocaine remaining after hydrolysis. The present study was undertaken to investigate whether or not relationships might exist between such molar concentration sums for different postmortem bodily fluids. Determinations of cocaine, benzoylecgonine, ecgonine methyl ester, and ecgonine were performed using liquid chromatography/mass spectrometry (LC/MS/MS) with heart blood, femoral blood, vitreous humor (VH), and urine (UR). The results demonstrate a strong correlation between blood and VH concentrations (correlation coefficients of 0.88,0.94), weak correlation between the UR and blood concentrations (correlation coefficients of 0.61,0.64), and weak correlation between UR and VH concentrations (correlation coefficient of 0.59). The results demonstrate that ecgonine is a significant hydrolysate with concentrations on the same order of magnitude as benzoylecgonine. The results are consistent with rapid distribution of the parent drug and its hydrolysates in the blood and VH. The strong correlation between the blood and VH demonstrates that VH is an important medium for toxicology testing when attempting to make a determination of cocaine intoxication. [source] Identification and fragmentation of hydrolyzed aluminum species by electrospray ionization tandem mass spectrometryJOURNAL OF MASS SPECTROMETRY (INCORP BIOLOGICAL MASS SPECTROMETRY), Issue 10 2004Arja Sarpola Abstract Earlier characterization of some hydrolysis products of AlCl3·6H2O was confirmed by electrospray ionization tandem mass spectrometry with increasing collision energy of projectile ions. At lower collision energies, the aqua ligands were stripped off. At higher energies, two hydroxo groups formed a bridging oxo group with loss of one water molecule. Aluminum complexes could also capture aqua ligands in the collision chamber so long as the parent ion did not fragment, and the fragment ion spectra broadened toward higher m/z values. The chloro ligands were eliminated as hydrochloric acid. The aluminum cores remained highly intact. Copyright © 2004 John Wiley & Sons, Ltd. [source] Stimulatory Effect of Procaine on the Growth of Several Microalgae and CyanobacteriaJOURNAL OF PHARMACY AND PHARMACOLOGY: AN INTERNATI ONAL JOURNAL OF PHARMACEUTICAL SCIENCE, Issue 2 2000TAKAHIRO SUZUKI Procaine has been used to stimulate plant growth and it has been noted that it also promotes growth of microorganisms. The effect of procaine hydrochloride concentration on the growth rates of several species of microalgae and cyanobacteria was studied under both photoautotropic and heterotrophic growth conditions. Procaine hydrochloride was added to cultures at concentrations over the range 0.01,1000 mg L,1. A stimulating effect of procaine hydrochloride on photoautotrophic growth was observed for the cyanobacteria Anabaena cylindrica and Anabaena variabilis, and for the salt-tolerant green algae Dunaliella primolecta and Dunaliella parva. During active growth in batch culture an increase in growth rate (compared with control culture without procaine hydrochloride) of about 25% was observed at 0.1 mg L,1 of procaine hydrochloride for A. cylindrica. However, procaine hydrochloride was toxic at concentrations of > 10 mg L,1. Simultaneous administration of hydrolysis products of procaine, p -amino-benzoic acid and diethyl aminoethanol, in lieu of procaine hydrochloride, was as effective as procaine in stimulating growth of A. cylindrica. Heterotrophic growth of Chlorella ellipsoidea and Prototheca zopfii was not stimulated by procaine hydrochloride over the concentration range studied (0.1,10 mg L,1). The combined effects of procaine hydrochloride concentration and four other environmental factors (temperature, light intensity, CO2 concentration in the flushing gas and NaCl concentration) on growth rate of D. primolecta was modelled using both a neural network approach and a response surface method. These results indicate that procaine hydrochloride exerts different effects on the growth of microalgal and cyanobacterial cells as functions of dosage, species and culture conditions. [source] Complete assignment of 1H and 13C NMR data for nine protopanaxatriol glycosidesMAGNETIC RESONANCE IN CHEMISTRY, Issue 7 2002Rongwei Teng Abstract Nine protopanaxatriol glycosides isolated from mild acid hydrolysis products of crude root saponins of Panax notoginseng were identified as 20(R)-ginsenoside-Rh1, 20(S)-ginsenoside-Rh1, ginsenoside-Rg1, -Re and -Rg2, notoginsenoside-R2 and -R1, a mixture of 25-hydroxy-20(S)-ginsenoside-Rh1 and its C-20 (R) epimer, ginsenoside-Rh4. The complete assignments of the 1H and 13C NMR chemical shifts for these glycosides were obtained by means of 2D NMR techniques, including 1H,1H COSY, ROESY, HMQC, HMBC and HMQC-TOCSY spectra. The glycosylation shift effect of protopanaxatriol and the differences in chemical shifts between 20(R)- and 20(S)-protopanaxatriol isomers are also discussed. Except for ginsenoside-Re and -Rg2, complete NMR assignments of the other seven glycosides are reported for the first time. Copyright © 2002 John Wiley & Sons, Ltd. [source] Behaviour of sulcotrione and mesotrione in two soilsPEST MANAGEMENT SCIENCE (FORMERLY: PESTICIDE SCIENCE), Issue 1 2008Hančne Chaabane Abstract The behaviour of sulcotrione, a recently introduced triketone herbicide, in various soil types was studied under laboratory conditions. In particular, degradation and sorption processes were examined on Ghent and Perpignan soils. Kinetics showed that the degradation of sulcotrione was influenced by biotic and/or abiotic factors. Half-lives ranged between 45 and 65 days. Among the degradation compounds identified were 1,3-cyclohexanedione (CHD) and 2-chloro-4-mesyl benzoic acid (CMBA), previously described as hydrolysis products, and, under special conditions, a derivative of phenylheptanoic acid (PHD). This new degradation product suggested that sulcotrione could follow two possible pathways in the soil, as in water. During the sorption study, a moderate retention of sulcotrione and CMBA relative to CHD and PHD, which were highly adsorbed whatever the soil type, was reported. Experiments carried out under the same conditions for sulcotrione and mesotrione, another triketone herbicide recommended in maize culture, made it possible to compare the two triketones and to conclude that they exhibited relatively similar behaviour in the soil, i.e. that their leaching potential needs to be properly addressed and risks evaluated. Copyright © 2007 Society of Chemical Industry [source] Synthesis, characterization, in vitro degradation and cytotoxicity of polyphosphazenes containing N -ethoxypyrrolidone side groupsPOLYMER INTERNATIONAL, Issue 2 2010Yunmei Bi Abstract A new biodegradable polyphosphazene (PYRMP) containing N -ethoxypyrrolidone and methoxyethoxyethoxy side groups was synthesized via a route of macromolecular substitution. The synthetic method of poly{bis[2-(2-oxo-1-pyrrolidinyl)ethoxy]phosphazene} (PYRP) was improved. The thermal properties of the polymers were investigated using differential scanning calorimetry. Degradation studies were carried out in vitro with varying pH conditions. The in vitro cytotoxicity of PYRMP and its hydrolysis products was evaluated using the methyl tetrazolium (MTT) cytotoxicity test in HepG2 cell culture. PYRMP and PYRP have low glass transition temperatures of ,68.8 and ,59.6 °C, respectively. The polymers show a higher degradation rate at pH = 5.0 than at both pH = 7.4 and 8.0. The degradation process of PYRMP in different buffer solutions is discussed. The MTT test reveals that PYRMP at concentrations below 800 µg mL,1 and its hydrolysis products are non-toxic to HepG2 cells. Moreover, the hydrolysis products diluted 10 times are able to promote cell proliferation. This study shows that polyphosphazene containing N -ethoxypyrrolidone subsituents provides interesting perspectives for various biomedical applications. Copyright © 2009 Society of Chemical Industry [source] Effect of products derived from hydrolysis of wheat and flaxseed non starch polysaccharides by carbohydrase enzymes on net absorption in enterotoxigenic Escherichia coli (K88) challenged piglet jejunal segmentsANIMAL SCIENCE JOURNAL, Issue 1 2010Elijah G. KIARIE ABSTRACT Enterotoxigenic Escherichia coli (ETEC) infection results in fluid and electrolyte losses in the small intestine. We investigated the effect of non-starch polysaccharides (NSP) hydrolysis products of wheat middlings (WM) and flaxseed (FS) on net absorption of fluid and solutes during ETEC challenge. Products were generated by incubating WM and FS with a blend of carbohydrase enzymes to produce 2 products: 80% ethanol-soluble (ES) and 80% ethanol-insoluble (EI) which were studied in 2 experiments in which 2 factors were investigated: products (EI vs. ES) and time of ETEC challenge (before vs. after perfusion). Pairs of small-intestine segments, one non-challenged and the other ETEC-challenged were perfused with products for 7.5 h. ETEC reduced fluid absorption by more than 380 µL/cm2 in saline (control) perfused segments, whereas this reduction was significantly (P < 0.05) less for the WM and FS products. Interaction (P > 0.05) between product and time of challenge was not observed. For WM, products effects on ETEC-challenged segments were such that perfusion of ES resulted in higher total solute (measured as osmolality) absorption than EI (138 vs. 103 µOsmol/cm2). In conclusion, hydrolysis products from WM and FS were beneficial in maintaining fluid balance during ETEC challenge, suggesting potential in controlling ETEC induced diarrhea in piglets. [source] Soil bacterium Pseudomonas sp.: destroyer of mustard gas hydrolysis productsBIOTECHNOLOGY JOURNAL, Issue 8 2007Nadezda Medvedeva Professor Abstract A bacterial culture capable of utilizing products of mustard gas hydrolysis as a source of carbon was isolated from soil. This culture was tolerant to organochlorine substances in the hydrolysate. The bacterium was identified as Pseudomonas sp. The bacterium utilizes the major product of mustard gas hydrolysis, thiodiglycol, through two pathways. One involves the oxidation of the primary alcoholic groups in thiodiglycol, yielding thiodiglycolic and thioglycolic acids. The cleavage of the C-S bonds in these acids gives rise to acetate, which is then used further in the cell metabolism. The other pathway involves the cleavage of the C-S bond in the thiodiglycol molecule, yielding ,-mercaptoethanol, which is transformed by Pseudomonas sp. into thioglycolic acid. The results show the promise of this bacterium for the bioremediation of mustard gas-contaminated soils. [source] Hydrolysis of Dinuclear Ruthenium Complexes [{CpRu(PPh3)2}2(,,,1:1 -L)][CF3SO3]2 (L=P4, P4S3): Simple Access to Metal Complexes of P2H4 and PH2SHCHEMISTRY - A EUROPEAN JOURNAL, Issue 23 2007Pierluigi Barbaro Dr. Abstract The reaction of [CpRu(PPh3)2Cl] (1) with half an equivalent of P4 or P4S3 in the presence of AgCF3SO3 as chloride scavenger affords the stable dimetal complexes [{CpRu(PPh3)2}2(,,,1:1 -P4)][CF3SO3]2, 3,CH2Cl2 (2) and [{CpRu(PPh3)2}2(,,,1:1 -Papical -Pbasal -P4S3)][CF3SO3]2, 0.5,C7H8 (3), in which the tetrahedral P4 and mixed-cage P4S3 molecules are respectively bound to two CpRu(PPh3)2 fragments through two phosphorus atoms. The coordinated cage molecules, at variance with the free ligands, readily react with an excess of water in THF under mild conditions. Among the hydrolysis products, the new, remarkably stable complexes [{CpRu(PPh3)2}2(,,,1:1 -P2H4)][CF3SO3]2 (4) and [CpRu(PPh3)2(,1 -PH2SH)]CF3SO3 (8) were isolated. In the former, diphosphane, P2H4, is coordinated to two CpRu(PPh3)2 fragments, and in the latter thiophosphinous acid, H2PSH, is coordinated to the metal centre through the phosphorus atom. All compounds were characterised by elemental analyses and IR and NMR spectroscopy. The crystal structures of 2, 3, 4 and 8 were determined by X-ray diffraction. [source] Loss of Ammine from Platinum(II) Complexes: Implications for Cisplatin Inactivation, Storage, and Resistance,CHEMISTRY - A EUROPEAN JOURNAL, Issue 9 2005Justin Kai-Chi Lau Abstract Potential consequences of the binding of the anticancer drug cisplatin to various biomolecules in the cell have been investigated by using a combined density functional theory and continuum dielectric model approach. Since the ammine ligands remain coordinated at the metal upon formation of the most frequent DNA adducts, whereas they were found to be displaced from the metal upon formation of drug metabolites, we have analyzed the factors governing ammine loss from platinum(II) complexes as a possible pathway of cisplatin inactivation. The calculations systematically show the effect of 1) the trans ligand, 2) the charge of complex, 3) the nucleophile, and 4) the environment on the thermodynamic instability and kinetic lability of the platinum,ammine bonds. After initial binding of cisplatin hydrolysis products to thioethers or thiols, loss of the ammine trans to this sulfur ligand rather than replacement of the sulfur ligand itself by other nucleophiles like guanine-N7 is predicted to be the predominant reaction. The results of this study contribute to an understanding of the modes of cisplatin inactivation prior to DNA binding, for example, by elevated glutathione levels in cisplatin-resistant cancer cells. [source] Investigating the presence of pesticide transformation products in water by using liquid chromatography-mass spectrometry with different mass analyzers,JOURNAL OF MASS SPECTROMETRY (INCORP BIOLOGICAL MASS SPECTROMETRY), Issue 2 2008Félix Hernández Abstract Many pesticide transformation products (TPs) can reach environmental waters as a consequence of their normally having a higher polarity than their parent pesticides. This makes the development of analytical methodology for reliable identification and subsequent quantification at the sub-microgram per liter levels necessary, as required under current legislation. In this paper we report the photodegradation of several pesticides frequently detected in environmental waters from the Spanish Mediterranean region using the high-resolution and exact-mass capabilities of hybrid quadrupole time-of-flight mass spectrometry (QTOF MS) hyphenated to liquid chromatography (LC). Once the main photodegradation/hydrolysis products formed in aqueous media were identified, analytical methodology for their simultaneous quantification and reliable identification in real water samples was developed using on-line solid-phase extraction (SPE)-LC-tandem MS with a triple-quadrupole (QqQ) analyzer. The methodology was validated in both ground and surface water samples spiked at the limit of quantification (LOQ) and 10 × LOQ levels, i.e. 50 and 500 ng/l, obtaining satisfactory recoveries and precision for all compounds. Subsequent analysis of ground and surface water samples resulted in the detection of a number of TPs higher than parent pesticides. Additionally, several soil-interstitial water samples collected from the unsaturated zone were analyzed to explore the degradation/transformation of some pesticides in the field using experimental plots equipped with lisimeters. Several TPs were found in these samples, with most of them having also been detected in ground and surface water from the same area. This paper illustrates the extraordinary potential of LC-MS(/MS) with QTOF and QqQ analyzers for qualitative/structural and quantitative analysis, respectively, offering analytical chemists one of the most powerful tools available at present to investigate the presence of pesticide TPs in water. Copyright © 2007 John Wiley & Sons, Ltd. [source] | ||||||||||||||||