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N HCl (n + hcl)
Selected AbstractsISOLATION and CHARACTERIZATION of MANGO PEEL PECTINSJOURNAL OF FOOD PROCESSING AND PRESERVATION, Issue 3 2000D.V. SUDHAKAR An efficient method for manufacture of pectin from Totapuri mango peels was standardized by studying various factors that govern the recovery and quality of pectin. Among the different organic and inorganic acids, 0.05 N HCl was found to be the best for recovery of pectin from mango peels. Optimum yield of pectin was obtained by taking two extractions each for one-hour duration employing a peel: extractant ratio of 1:2 and by alcohol precipitation method. Dried mango peels could be stored for six months at ambient conditions (14.5,33.9C) without any significant effect on the recovery of pectin. Pectin extract, an intermediate product in the manufacture of pectin, could be stored for one month either at low temperature (6C±2) or at ambient conditions (24.5,33.0C) by the addition of 700 ppm SO2 with minimum loss in the recovery of pectin. Using the optimum extracting conditions about 20.8% (DWB) of purified pectin was obtained from mango peels. the powdered pectin could be stored for over 6 months without any deterioration in quality when packed in airtight containers at ambient conditions. [source] ORGANIC ACIDS PROFILE IN TOMATO JUICE BY HPLC WITH UV DETECTIONJOURNAL OF FOOD QUALITY, Issue 1 2007OMBRETTA MARCONI ABSTRACT A simple method was developed to determine 10 organic acids simultaneously in tomato products using reverse-phase high performance liquid chromatography (HPLC) column with the diode array detector set at 210 nm. After centrifugation and filtration, the samples were passed through to an anion exchange resin and the organic acids were released using 0.1 N HCl. The chromatographic separation was achieved with isocratic analysis in a 20-min run. The method was reliable and sensitive. The coefficient of determination of the standard calibration curve is 0.9925 , r2 , 0.9999 and the limit of detection ranged from 0.08 to 6.00 mg/kg for trans -aconitic acid and acetic acid, respectively. The limit of quantification ranged from 0.19 to 15.18 mg/kg for trans-aconitic and acetic acid, respectively. To establish the efficiency of the anion resin the procedure was applied to a standard solution of a mixture of organic acids. The organic acids recovery ranged from 87.0% ± 1.9 for citramalic acid to 109.9% ± 5.2 for fumaric acid. [source] Production and Stability Studies of a Neurotoxin Produced by Clostridium sp.JOURNAL OF FOOD SCIENCE, Issue 3 2006ABSTRACT: A neurotoxigenic Clostridium sp. (RKD) isolated from intestine of decaying fish produced a neurotoxin that was neutralized by botulinum antitoxin (A+B+E) when tested by mouse protection bioassay. An amplicon of expected size (approximately 700 bp) was generated with primers specific for BoNT/B. Toxin was maximally released in the culture supernatant in the late stationary phase and was dependent on media composition. Growth was optimal in trypticase peptone yeast-extract glucose (TPYG) medium in a pH range of 7.5 to 8.0 and at a temperature between 35°C to 40°C while toxin production was optimum at 37°C (3 to 4 × 103 minimum lethal dose per milliliter) without any protease treatment. There was no correlation between growth and toxin production when cells were grown in media containing different concentrations of NaCl (0% to 5%). Toxin in the culture supernatant was more stable (50% reduction at 50°C in 90 min) than the partially purified fraction. Toxicity was destroyed gradually after increasing the number of freeze-thaw cycles and was almost completely inactivated after 5 cycles. It was completely inactivated by overnight treatment of 1 N NaOH while it retained 1.5% activity with a similar treatment with 1 N HCl. [source] Instrumental and Consumer Evaluation of Beef Patties Extended with Extrusion-Textured Whey ProteinsJOURNAL OF FOOD SCIENCE, Issue 3 2002A. B. Hale ABSTRACT: : We extruded a dry mix of 2 parts whey protein concentrate (80% protein) and 1 part cornstarch using water, 0.1 N HCl, or 0.2 M NaOH as the liquid, or adding calcium (1.69% w/w) to the dry mix with water as the liquid. The functionality and acceptability of textured whey protein (TWP) extrudates was determined. Ground beef patties containing up to 40% (w/w) of hydrated TWP extrudates made with base (TWPbase) were as acceptable to a consumer panel as all beef patties. Additionally, patties containing 40% (w/w) TWPbase incurred less cook loss and less diameter reduction after cooking, but were less cohesive than all beef patties. [source] Simple and high radiochemical yield synthesis of 2,-Deoxy-2,-[18F]fluorouridine via a new nosylate precursorJOURNAL OF LABELLED COMPOUNDS AND RADIOPHARMACEUTICALS, Issue 14 2006Se Hun Kang Abstract We synthesized 2'-deoxy-2'-[18F]fluorouridine (7) as a radiotracer for positron emission tomography from a new nosylate precursor (6). This new precursor was synthesized from uridine in four steps. The overall synthetic yield was 9.4% and we have high stability of >98% purity up to 6 months at 4°C. The optimal manual [18F]fluorination conditions were 30 mg of the precursor 6 in 500 µl of acetonitrile at 145°C for 15 min with 370 MBq of [18F]fluoride. The [18F]fluorination yield was 76.5±2.7% (n = 3). After hydrolysis of protecting groups with 1 N HCl and purification by HPLC, the overall radiochemical yield and purity were 26.5±1.4% and 98.2±2.5%, respectively. The preparation time was 70.0±10.5 min (n = 3 for each result). We also developed an automated method with a radiochemical yield and purity of 24.0±2.8 and 98.0±1.5% (n = 10) using a GE TracerLab MX chemistry module. This new nosylate precursor for 2'-deoxy-2'-[18F]fluorouridine synthesis showed higher radiochemical yields and reproducibility than previous methods. Copyright © 2006 John Wiley & Sons, Ltd. [source] Polymerization of substituted phenylacetylenes with a novel, water-soluble Rh,vinyl complex in waterJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 9 2004Keiji Kanki Abstract A novel, water-soluble Rh complex, (nbd)Rh[PPh2(m -NaOSO2C6H4)] [C(Ph)CPh2] (1) was synthesized by the reaction of [(nbd)RhCl]2, Ph2P(m -NaOSO2C6H4) and Ph2CC(Ph)Li, whose structure was determined by NMR and IR spectroscopies. The Rh catalyst 1 induced the polymerization of phenylacetylene (PA) in water to give two kinds of polymers; one was soluble in organic solvents such as tetrahydrofuran (THF) and CHCl3, and the other was insoluble in common organic solvents. The polymerization of sodium p -ethynylbenzoate (p -NaOCO-PA) homogeneously proceeded with 1 in water at 60 °C to give the polymer in high yield. Poly(p -NaOCO-PA) was treated with 1 N HCl and then reacted with (CH3)3SiCHN2 to obtain poly(p -MeOCO-PA). The methyl-esterified polymer was insoluble in THF and CHCl3, which suggests that the formed poly(p -MeOCO-PA) has cis,cisoidal structure. The polymer obtained from the polymerization of [p -CH3(OCH2CH2)2O2CC6H4]CCH with 1 in water was soluble in methanol, ethanol, and THF, and partly soluble in water. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 2100,2105, 2004 [source] Pretreatment technique for siderite removal for organic carbon isotope and C:N ratio analysis in geological samplesRAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 6 2008Toti E. Larson A method for the removal of siderite from geological samples to determine organic carbon isotope compositions using elemental analysis isotope ratio mass spectrometry is presented which includes calculations for % organic carbon in samples that contain diagenetic carbonate. The proposed method employs in situ acidification of geological samples with 6,N HCl and silver capsule sample holders and was tested on modern peach leaf samples (NIST 1547) and ancient lacustrine samples from Valles Caldera, New Mexico. The in situ acidification technique eliminates potential errors associated with the removal of soluble organic material using standard acid decanting techniques and allows for removal of the less soluble siderite, which is not efficiently removed using vapor acidification techniques. Copyright © 2008 John Wiley & Sons, Ltd. [source] Relationship between quantitative assessments of salivary buffering capacity and ion activity product for hydroxyapatite in relation to cariogenic potentialAUSTRALIAN DENTAL JOURNAL, Issue 2 2008H Aiuchi Abstract Background:, The ion activity product for hydroxyapatite (IpHA) is a comprehensive parameter reflecting pH, calcium and phosphate ion concentration in saliva which govern the degree of saturation with respect to the dissolving tooth mineral. The aim of this study was to evaluate the relationship between quantitative assessments of salivary buffering capacity and IpHA in relation to cariogenic potential. Methods:, Stimulated whole saliva was collected from 33 patients, and the initial pH of samples was measured using a hand-held pH meter. Then samples were titrated with 0.1 N HCl to evaluate buffering capacities and divided into three groups (high, medium and low). After measuring concentrations of calcium and phosphate ions in the samples, IpHA was calculated using the values of the ion concentrations and pH. Differences in the mean pH values, the concentrations of calcium, phosphate ions and log[IpHA] among three groups were analysed using the Kruskal Wallis and the Mann-Whitney non-parametric test, p < 0.05. Results:, After HCl 50 ,L titration, there were statistical differences of the mean pH and IpHA among each buffering capacity group. Moreover, after 50 ,L HCl titration, there was an excellent correlation between the buffer capacity and log[IpHA]. Conclusions:, The pH change for saliva after HCl titration has a significant influence on the rate of IpHA. [source] Pharmacokinetics of SB-247083, a potent and selective endothelinA receptor antagonist, in the rat, dog, and monkeyBIOPHARMACEUTICS AND DRUG DISPOSITION, Issue 8 2002Keith W. Ward Abstract The endothelins (ET) are among the most potent vasoconstrictors identified to date, and have been implicated in such diseases as renal failure, pulmonary hypertension, atherosclerosis, and congestive heart failure. There is currently interest in developing selective antagonists of the ET-A subtype receptor, and one such antagonist is SB-247083 ((E)-[1-butyl-5-[2-(2-carboxyphenyl) methoxy-4-chlorophenyl]-1H-pyrazole-4-yl]-2-[5-methoxydihydrobenzofuran-6-yl]methyl]-2-propionic acid). This investigation was conducted to evaluate the preclinical pharmacokinetics of SB-247083. Clearance of SB-247083 was low to moderate in the rat and monkey, and high in the dog. Oral bioavailability of SB-247083 administered as a solid formulation of the free acid was 24% in the rat, but low in the dog (4%) and the monkey (2%). An extensive in vitro salt form and formulation screen resulted in the identification of a formulation containing the monoarginyl salt with improved dissolution properties. This formulation provided a 2- to 4-fold increase in oral bioavailability in each of the preclinical species. In the dog, this improvement was reversed by the pre-administration of 0.1 N HCl to normalize the achlorhydric fasting dog stomach. These data show that SB-247083 may have suitable drug properties for progression in development. Copyright © 2002 John Wiley & Sons, Ltd. [source] Synthesis and Cytotoxicity of Enantiomerically Pure [1,2-Diamino-1-(4-fluorophenyl)-3-methylbutane]platinum(II) ComplexesCHEMMEDCHEM, Issue 6 2006Anja Dullin Abstract A series of leaving group derivatives of enantiomerically pure [1,2-diamino-1-(4-fluorophenyl)-3-methylbutane]platinum(II) complexes were synthesized and tested for cytotoxicity. The enantiomeric purity was determined by 1H,NMR spectroscopy on the final diamines after derivation with (1R)-myrtenal. For coordination to platinum, the diamines were reacted with K2PtI4. The treatment of diiodoplatinum(II) complexes (4F-Ph/iProp-PtI2) with Ag2SO4 resulted in the sulfatoplatinum(II) complexes (4F-Ph/iProp-PtSO4), which can be easily transformed to dichloroplatinum(II) complexes (4F-Ph/iProp-PtCl2) with 2,n HCl. The importance of the leaving groups and the configuration at the diamine ligand on the antiproliferative effects was evaluated on the hormone-dependent MCF-7 and the hormone-independent MDA-MB 231 breast cancer cell lines as well as the LNCaP/FGC prostate cancer cell line. (R,R)-4F-Ph/iProp-PtCl2 was identified as the most active platinum(II) complex. The 3-methyl group increased antiproliferative effects relative to the [1,2-diamino-1-(4-fluorophenyl)butane]platinum(II) complexes described in an earlier study. [source] | |||||||||||||