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Product Yield (product + yield)
Kinds of Product Yield Selected AbstractsProduct Yield and Gaping in Cold-smoked Atlantic Salmon (Salmo salar) Fillets as Influenced by Different Injection-salting TechniquesJOURNAL OF FOOD SCIENCE, Issue 5 2003S. Birkeland ABSTRACT Product yield and fillet gaping severity were determined in cold-smoked Atlantic salmon fillets subjected to injection-salting. Effects of process parameter settings (brine injection pressure, number of repeated injections, needle speed, injection of brine in 1 or 2 directions, and chilled fillet resting before smoking) were tested. Repeated injections increased the yield up to 5.3% (wt/wt). Increasing injection pressure significantly increased the severity of fillet gaping in smoked fillets by 18%. Brine injection directions or needle speed did not affect smoking yield. The stability of the injection system was high. The results show that choice of process parameter settings during injection-salting affects product yield after smoking. [source] Modulation of Phosphoenolpyruvate Synthase Expression Increases Shikimate Pathway Product Yields in E. coliBIOTECHNOLOGY PROGRESS, Issue 6 2002Jian Yi Product yields in microbial synthesis are ultimately limited by the mechanism utilized for glucose transport. Altered expression of phosphoenolpyruvate synthase was examined as a method for circumventing these limits. Escherichia coli KL3/pJY1.216A was cultured under fed-batch fermentor conditions where glucose was the only source of carbon for the formation of microbial biomass and the synthesis of product 3-dehydroshikimic acid. Shikimate pathway byproducts 3-deoxy- d - arabino -heptulosonic acid, 3-dehydroquinic acid, and gallic acid were also generated. An optimal expression level of phosphoenolpyruvate synthase was identified, which did not correspond to the highest expression levels of this enzyme, where the total yield of 3-dehydroshikimic acid and shikimate pathway byproducts synthesized from glucose was 51% (mol/mol). For comparison, the theoretical maximum yield is 43% (mol/mol) for synthesis of 3-dehydroshikimic acid and shikimate pathway byproducts from glucose in lieu of amplified expression of phosphoenolpyruvate synthase. [source] Product Yield and Gaping in Cold-smoked Atlantic Salmon (Salmo salar) Fillets as Influenced by Different Injection-salting TechniquesJOURNAL OF FOOD SCIENCE, Issue 5 2003S. Birkeland ABSTRACT Product yield and fillet gaping severity were determined in cold-smoked Atlantic salmon fillets subjected to injection-salting. Effects of process parameter settings (brine injection pressure, number of repeated injections, needle speed, injection of brine in 1 or 2 directions, and chilled fillet resting before smoking) were tested. Repeated injections increased the yield up to 5.3% (wt/wt). Increasing injection pressure significantly increased the severity of fillet gaping in smoked fillets by 18%. Brine injection directions or needle speed did not affect smoking yield. The stability of the injection system was high. The results show that choice of process parameter settings during injection-salting affects product yield after smoking. [source] Rate coefficients and mechanisms of the reaction of cl-atoms with a series of unsaturated hydrocarbons under atmospheric conditionsINTERNATIONAL JOURNAL OF CHEMICAL KINETICS, Issue 8 2003John J. Orlando Rate coefficients and/or mechanistic information are provided for the reaction of Cl-atoms with a number of unsaturated species, including isoprene, methacrolein (MACR), methyl vinyl ketone (MVK), 1,3-butadiene, trans -2-butene, and 1-butene. The following Cl-atom rate coefficients were obtained at 298 K near 1 atm total pressure: k(isoprene) = (4.3 ± 0.6) × 10,10cm3 molecule,1 s,1 (independent of pressure from 6.2 to 760 Torr); k(MVK) = (2.2 ± 0.3) × 10,10 cm3 molecule,1 s,1; k(MACR) = (2.4 ± 0.3) × 10,10 cm3 molecule,1 s,1; k(trans -2-butene) = (4.0 ± 0.5) × 10,10 cm3 molecule,1 s,1; k(1-butene) = (3.0 ± 0.4) × 10,10 cm3 molecule,1 s,1. Products observed in the Cl-atom-initiated oxidation of the unsaturated species at 298 K in 1 atm air are as follows (with % molar yields in parentheses): CH2O (9.5 ± 1.0%), HCOCl (5.1 ± 0.7%), and 1-chloro-3-methyl-3-buten-2-one (CMBO, not quantified) from isoprene; chloroacetaldehyde (75 ± 8%), CO2 (58 ± 5%), CH2O (47 ± 7%), CH3OH (8%), HCOCl (7 ± 1%), and peracetic acid (6%) from MVK; CO (52 ± 4%), chloroacetone (42 ± 5%), CO2 (23 ± 2%), CH2O (18 ± 2%), and HCOCl (5%) from MACR; CH2O (7 ± 1%), HCOCl (3%), acrolein (,3%), and 4-chlorocrotonaldehyde (CCA, not quantified) from 1,3-butadiene; CH3CHO (22 ± 3%), CO2 (13 ± 2%), 3-chloro-2-butanone (13 ± 4%), CH2O (7.6 ± 1.1%), and CH3OH (1.8 ± 0.6%) from trans -2-butene; and chloroacetaldehyde (20 ± 3%), CH2O (7 ± 1%), CO2 (4 ± 1%), and HCOCl (4 ± 1%) from 1-butene. Product yields from both trans -2-butene and 1-butene were found to be O2 -dependent. In the case of trans -2-butene, the observed O2 -dependence is the result of a competition between unimolecular decomposition of the CH3CH(Cl)CH(O,)CH3 radical and its reaction with O2, with kdecomp/kO2 = (1.6 ± 0.4) × 1019 molecule cm,3. The activation energy for decomposition is estimated at 11.5 ± 1.5 kcal mol,1. The variation of the product yields with O2 in the case of 1-butene results from similar competitive reaction pathways for the two ,-chlorobutoxy radicals involved in the oxidation, ClCH2CH(O,)CH2CH3 and ,OCH2CHClCH2CH3. © 2003 Wiley Periodicals, Inc. Int J Chem Kinet 35: 334,353, 2003 [source] Shock tube pyrolysis of thiopheneINTERNATIONAL JOURNAL OF ENERGY RESEARCH, Issue 3 2003Hafeez Ur Rahman Memon Abstract The kinetics of the thermal decomposition of thiophene diluted in argon have been studied behind reflected shock waves in a single pulse shock tube over the temperature range 1598,2022 K and pressures between 2.5 and 3.44 bar. Product yields and composition were determined using capillary column gas chromatography with flame ionization detection and flame photometric sulphur selective detection. The principal hydrocarbon product at all temperatures was ethyne. Ethanethiol was found to be the major sulphur product together with H2S formed in significant concentrations at lower temperatures. Carbon disulphide was also formed at higher temperatures. Additional reaction products were CH4, C2H4, C3H4, C4H3, C4H6, C4H4, C6H6 and C4H2 with some traces were found of C5 and C6H5 species. It was concluded that pyrolysis of thiophene is initiated by C,S bond fission to form the C4H4S radical which reacts to give C4H3 + SH together with the reaction giving C3H4 + CS. The rate expression obtained for the pyrolysis reaction was k (C4H4S)=2.2×1011 exp (270 kJ mol,1) s,1. Copyright © 2002 John Wiley & Sons, Ltd. [source] Batch production of L(+) lactic acid from whey by Lactobacillus casei (NRRL B-441)JOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 9 2004Ali O Büyükkileci Abstract The effects of temperature, pH, and medium composition on lactic acid production by Lactobacillus casei were investigated. The highest lactic acid productivity values were obtained at 37 °C and pH 5.5. The productivity was 1.87 g dm,3 h,1 at 37 °C in shake flasks. In the fermenter, a productivity of 3.97 g dm,3 h,1 was obtained at pH 5.5. The most appropriate yeast extract concentration was 5.0 g dm,3. Whey yielded a higher productivity value than the analytical lactose and glucose. Initial whey lactose concentration did not affect lactic acid productivity. MnSO4 ·H2O was necessary for lactic acid production by L casei from whey. Product yields were approximately 0.93 g lactic acid g lactose,1. Copyright © 2004 Society of Chemical Industry [source] Butanolysis of 2-methylbenzenediazonium ions: product distribution, rate constants of product formation, and activation parametersJOURNAL OF PHYSICAL ORGANIC CHEMISTRY, Issue 5 2009M. José Pastoriza-Gallego Abstract We have determined the product distributions, the rate constants of product formation and substrate loss, and the activation parameters for the butanolysis of 2-methylbenzenediazonium, 2MBD, tetrafluoroborate in aqueous 1-Butanol (BuOH) solutions by combining UV,VIS spectroscopy, high performance liquid chromatography (HPLC), and a derivatization protocol that traps unreacted 2MBD as a stable azo dye. BuOH/H2O solutions are miscible over a narrow composition range, but in reverse micelles composed of sodium dodecyl sulfate, SDS, BuOH, and water, are miscible between 45,80%. Two major and two minor dediazoniation products are observed, 2-cresol, ArOH, 2-butyl-tolyl-ether, ArOBu, and small amounts of 2-chlorobenzene, ArCl (from HCl added to control solution acidity) and toluene, ArH (a reduction product). Product yields depend on experimental conditions, but quantitative conversion to products is achieved over the entire composition ranges investigated. The observed rate constants, kobs, obtained by monitoring 2MBD loss or by monitoring ArOH or ArOBu formation, are the same and they are only modestly affected by changes in the solution composition. The activation parameters obtained from the effect of temperature on kobs show that the enthalpy of activation is relatively high compared to those found in bimolecular reactions and the entropy of activation is small but positive. The results suggest that 2MBD is mainly sampling in the BuOH-H2O rich interfacial region of the reverse micelle and are consistent with 2MBD decomposing through a DN,+,AN mechanism, i.e., a rate limiting formation of an aryl cation that reacts immediately with nucleophiles. Copyright © 2008 John Wiley & Sons, Ltd. [source] High-level cell-free synthesis yields of proteins containing site-specific non-natural amino acidsBIOTECHNOLOGY & BIOENGINEERING, Issue 2 2009Aaron R. Goerke Abstract We describe an E. coli -based cell-free system for the production of proteins with a non-natural amino acid (nnAA) incorporated site-specifically (modified protein). The mutant Methanococcus jannaschii tyrosyl-tRNA synthetase (mTyrRS) and tRNATyr pair were used as orthogonal elements. The mTyrRS experienced proteolysis and modified protein yields improved with higher synthetase addition (200,300 µg/mL). Product yields were also improved by increasing levels of total protein to 20 mg protein/mL and available vesicle surface area to 0.5 m2/mL. This new E. coli -based cell-free procedure produced up to 400 µg/mL of eCAT109pAz, 660 µg/mL of eDHFR10pAz, and 210 µg/mL of mDHFR31pAz with p -azido- L -phenylalanine (pAz) incorporated site-specifically at the amber nonsense codon. O -methyl- L -tyrosine and p -acetyl- L -phenylalanine were incorporated by similar protocols. The desired specificity for incorporation of the nnAA by the cell-free system was confirmed. Additionally, the modified proteins were enzymatically active and reactive for copper(I)-catalyzed (3,+,2) cycloadditions (click chemistry). Biotechnol. Bioeng. 2009;102: 400,416. © 2008 Wiley Periodicals, Inc. [source] Modulation of Phosphoenolpyruvate Synthase Expression Increases Shikimate Pathway Product Yields in E. coliBIOTECHNOLOGY PROGRESS, Issue 6 2002Jian Yi Product yields in microbial synthesis are ultimately limited by the mechanism utilized for glucose transport. Altered expression of phosphoenolpyruvate synthase was examined as a method for circumventing these limits. Escherichia coli KL3/pJY1.216A was cultured under fed-batch fermentor conditions where glucose was the only source of carbon for the formation of microbial biomass and the synthesis of product 3-dehydroshikimic acid. Shikimate pathway byproducts 3-deoxy- d - arabino -heptulosonic acid, 3-dehydroquinic acid, and gallic acid were also generated. An optimal expression level of phosphoenolpyruvate synthase was identified, which did not correspond to the highest expression levels of this enzyme, where the total yield of 3-dehydroshikimic acid and shikimate pathway byproducts synthesized from glucose was 51% (mol/mol). For comparison, the theoretical maximum yield is 43% (mol/mol) for synthesis of 3-dehydroshikimic acid and shikimate pathway byproducts from glucose in lieu of amplified expression of phosphoenolpyruvate synthase. [source] Synthesis of C1 -Symmetric BINOLs Employing N-Heterocyclic Carbene,Copper ComplexesCHEMISTRY - A EUROPEAN JOURNAL, Issue 38 2009Alain Grandbois Fucntionalizing BINOL: Bis-NHCCu complexes can be used for the oxidative coupling of 2-naphthols. Product yields are highest when using electron-deficient 2-naphthols. Mixed couplings between electron-rich and electron-poor 2-naphthols can be conducted to give good yields of the mixed products. [source] Anaerobic homolactate fermentation with Saccharomyces cerevisiae results in depletion of ATP and impaired metabolic activityFEMS YEAST RESEARCH, Issue 3 2009Derek A. Abbott Abstract Conversion of glucose to lactic acid is stoichiometrically equivalent to ethanol formation with respect to ATP formation from substrate-level phosphorylation, redox equivalents and product yield. However, anaerobic growth cannot be sustained in homolactate fermenting Saccharomyces cerevisiae. ATP-dependent export of the lactate anion and/or proton, resulting in net zero ATP formation, is suspected as the underlying cause. In an effort to understand the mechanisms behind the decreased lactic acid production rate in anaerobic homolactate cultures of S. cerevisiae, aerobic carbon-limited chemostats were performed and subjected to anaerobic perturbations in the presence of high glucose concentrations. Intracellular measurements of adenosine phosphates confirmed ATP depletion and decreased energy charge immediately upon anaerobicity. Unexpectedly, readily available sources of carbon and energy, trehalose and glycogen, were not activated in homolactate strains as they were in reference strains that produce ethanol. Finally, the anticipated increase in maximal velocity (Vmax) of glycolytic enzymes was not observed in homolactate fermentation suggesting the absence of protein synthesis that may be attributed to decreased energy availability. Essentially, anaerobic homolactate fermentation results in energy depletion, which, in turn, hinders protein synthesis, central carbon metabolism and subsequent energy generation. [source] Physicochemical, textural, sensory characteristics and storage stability of goat meat patties extended with full-fat soy paste and soy granulesINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 3 2008Arun K. Das Summary The performance of full-fat soy paste (FFSP) with reduced beany flavour made by simple processing technology was compared with the commercially available textured soy granules in goat meat patties. Addition of soy proteins (soy paste and soy granules) did not significantly affect the emulsion stability and product yield. Shrinkage of patties with soy paste was comparable with control. A significant (P < 0.05) reduction in redness and increase in yellowness of patties was due to addition of soy proteins than in control. Patties with soy paste had comparable but slightly higher total lipid and cholesterol content with that of control but significantly (P < 0.05) higher than patties with soy granules. Lower force was required to compress or shear the sample, as hardness decreased in soy-added patties. Flavour and overall acceptability scores between control and patties with soy paste did not differ significantly, whereas patties with soy granules were rated significantly lower. The patties remained stable with minor changes in physicochemical, microbiological and sensory quality during refrigerated storage (4 ± 1 °C) for 20 days. It is concluded from this study that FFSP had potential application similar to commercially available textured soy granules in comminuted meat products. [source] Effect of egg proteins on the quality and refrigerated storage life of chicken patties made with broiler-spent hen meat and by-products,INTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 5 2007A. Kalaikannan Summary The effects of whole egg powder (WEP), dried albumen (DA), dried yolk (DY) at a 1% level and liquid egg (LE) at a 3.7% level on the quality characteristics and refrigerated storage (4 ± 1 °C) stability of chicken patties made with meat and by-products of broiler-spent hens were evaluated. The addition of egg powders significantly enhanced the emulsion stability (ES) and product yield compared with control and LE. There was a marked increase in moisture content and sensory attributes by the addition of egg powders. During the refrigerated storage (4 ± 1 °C), thio-barbituric acid number (TBARS), aerobic plate count (APC) and psychrophilic count increased in all samples. Incorporation of DA and DY significantly reduced the TBARS number and APC during the storage over control. The addition of DA, DY and WEP significantly lowered the psychrophilic counts. Treated and control patties packaged in LDPE (low-density polyethylene) pouches were acceptable for 20 days and 15 days, respectively. [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] Effect of Long Chain Fatty Acids on Organocatalytic Aqueous Direct Aldol ReactionsADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 17 2009Nobuyuki Mase Abstract In an organocatalyzed, aqueous direct aldol reaction, the addition of a long chain fatty acid (1,mol%) such as stearic acid or erucic acid improved the aldol product yield and the enantioselectivity with low catalyst loading (1,mol%). The small particle size of the emulsion (less than 1,,m) was a key to the enhanced reactivity as shown by dynamic light scattering (DLS) analyses. [source] Stable and Catalytically Highly Active ansa Compounds with Cycloalkyl Moieties as Bridging UnitsADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 1-2 2009Alejandro Capapé Abstract The complexes Mo{,5 -C5H4[CH(CH2)3]-,1 -CH}(CO)3 (2a) and W{,5 -C5H4[CH(CH2)3]-,1 -CH}CO)3 (2b) were synthesized by reacting spiro[4.2]bicyclo[4.1]deca-6,8-diene (1) with the tri(acetonitrile)tri(carbonyl)metal complexes M(CO)3(CH3CN)3 (M=Mo, W). Thermogravimetric (TGA) measurements confirm that the complexes are stable up to 140,°C in air in the solid state. The complexes 2a and 2b are very active catalysts at room temperature for the epoxidation of cyclooctene with tert -butyl hydroperoxide (TBHP) as oxidant, reaching TOFs of up to 3650,h,1. Complex 2a achieves a quantitative product yield without formation of any by-products within 1.5,h, outperforming previously published ansa compounds and performing on par with the cyclopentadienyltri(carbonyl)(halo)- or (alkyl)molybdenum compelxes CpMo(CO)3R (R=Hal, Me, Et). [source] Combining microwave and ultrasound irradiation for rapid synthesis of nanowires: a case study on Pb(OH)BrJOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 12 2009Xiao-Fang Shen Abstract BACKGROUND: One-dimensional (1D) nanostructures such as wires, tubes and belts have attracted much attention in recent years because of their fascinating properties and promising applications, and various methods have been developed to prepare 1D nanostructures. Microwave and ultrasound, two methodologies for rapid synthesis, have both been applied to fabricate nanostructures. This paper reports on combining microwave and ultrasound irradiation as a new strategy for rapid synthesis of nanowires. Using Pb(OH)Br as a study case, nanowires were rapidly synthesized under the combined irradiation. The use of the ionic liquid 1-butyl-3-methylimidazolium bromide as a structure-directing agent and microwave absorbent significantly simplified the preparation procedure. RESULTS: Combined microwave,ultrasound irradiation at (50 W,50 W) greatly reduced the reaction time (10 min) and significantly increased the product yield (45.0%) in comparison with conventional heating (24 h reaction time, 23.0% yield). Combined microwave,ultrasound irradiation at (50 W,50 W) also changed the resultant wires from 20,30 µm diameter and 2,3 mm long to 80,800 nm and 50,100 µm, respectively. Further increase in power of the combined irradiation (250 W,50 W) led to a dramatic reduction in the reaction time (80 s) with a slightly increased yield of 48.2%. CONCLUSIONS: The obvious advantages of combined microwave,ultrasound irradiation are marked improvement of the product yield, significant enhancement of reaction rate and increased aspect ratio of the 1D structure. Copyright © 2009 Society of Chemical Industry [source] Effect of oxygen transfer rates on alcohols production by Candida guilliermondii cultivated on soybean hull hydrolysateJOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 2 2009Ângela Cristina Schirmer-Michel Abstract BACKGROUND: In this research the use of soybean hull hydrolysate (SHH) as substrate for xylitol and ethanol production using an osmotolerant strain of Candida guilliermondii was studied. The production of alcohols was investigated in batch cultivations in which the variable parameter was the volumetric oxygen mass transfer coefficient (kLa) obtained from three different conditions of air supply: anaerobic (150 rpm, no aeration); microaerobic (300 rpm, 1 vvm), and aerobic (600 rpm, 2 vvm), corresponding to kLa values of 0; 8; and 46 h,1, respectively. RESULTS: SHH, although presenting a very high osmotic pressure (1413 mOsm kg,1), was completely metabolized under aerobic conditions with high biomass productivities of 0.49 g cells (L h),1, with little formation of ethanol. Xylitol was produced under microaeration, with product yield of 0.22 g g,1 xylose, with the formation of glycerol as a by-product. No xylose was metabolized under anaerobic conditions, but ethanol was produced from hexoses with high product yields of 0.5 g g,1. CONCLUSION: These results suggest that the hydrolysis of soybean hull and its conversion to ethanol and other alcohols could be an important use of this agro-industrial waste, which could be used for biofuel, xylitol or biomass production, depending on the aeration conditions of the cultures. Copyright © 2008 Society of Chemical Industry [source] Effects of supplementation of succinic acid on the production and molecular weight distribution of exopolysaccharides by Antrodia camphorata in batch culturesJOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 2 2005Chin-Hang Shu Abstract The effects of organic acid supplementation on both yields and molecular weight distributions of exopolysaccharide (EPS) of Antrodia camphorata were investigated in shaker flasks and air-lift bioreactors. In the shaker flask study, five out of six organic acid-supplemented cultures showed negative effects on cell growth, the exception being pyruvic acid-supplemented culture; lower number average molecular weights (Mn) of EPS were obtained in all the supplemented cultures. EPS production was enhanced by 31% due to the addition of succinic acid. Optimum product yield was obtained between 2.0 and 3.0 g dm,3 succinic acid; however, the specific production of EPS increased monotonically as succinic acid concentration was increased from 0 to 5 g dm,3. Enhancement of EPS yield by 28% and a higher Mn of EPS (around 310 kDa) due to the addition of succinic acid were also demonstrated in an air-lift bioreactor. In addition, a novel fermentation process resistant to EPS degradation is proposed, based on the inhibition of ,-glucanase activity by the supplementation with succinic acid. Copyright © 2004 Society of Chemical Industry [source] D -Lactic acid production from waste cardboardJOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 1 2005Remedios Yáñez Abstract The effects caused by alkaline treatment on the susceptibility of waste cardboard to enzymatic hydrolysis have been studied. Optimised conditions leading to extensive saccharification of both cellulose (870 g kg,1 conversion) and hemicelluloses (845 g kg,1 conversion) were identified. Samples treated under selected operational conditions were employed for producing D -lactic acid by simultaneous saccharification and fermentation (SSF) in media containing cellulases, ,-glucosidase and Lactobacillus coryniformis ssp torquens cells. SSF fed-batch experiments led to D -lactic acid concentrations up to 23.4 g dm,3 at a product yield of 514 g lactic acid kg,1 of potential glucose and a volumetric productivity of 0.48 g dm,3 h,1. Copyright © 2004 Society of Chemical Industry [source] Midpoint CD34 measurement as a predictor of PBPC product yield in pediatric patients undergoing high-dose chemotherapy ,JOURNAL OF CLINICAL APHERESIS, Issue 3 2006Rameshwar S. Sidhu Abstract High-dose chemo/radiotherapy of sensitive tumors requires PBPC rescue doses of >3×106 CD34/kg (range: 3,20×106 CD34/kg). Because of the diversity of stem cell treatment protocols and clinical presentation of patients at the time of peripheral blood progenitor cell (PBPC) harvest, the use of the mid-point CD34 positive cell measurement was initiated to predict the final CD34-positive cell product yield/stem cell harvest. The measurement of CD34-positive cells at the mid-point of the initial setting of 5 total blood volumes (TBV) allows for the extension, shortening, or no change in the TBV processing to achieve a maximum goal of CD34-positive cells/kg body weight required for stem cell transplantation. The estimation of mid-point CD34-positive cells guided our center to extend 22 procedures, shorten 26 procedures, and leave 20 procedures unchanged. This investigation addresses three aspects of PBPC collection in pediatric patients: (1) the processing of large blood volumes (more than the defined 3 TBV and maximum up to 13 TBV in one session) to achieve good efficiency of the procedure; (2) the use of the mid-point CD34 measurement at 2.5 of 5 TBV initially set to predict the maximum goal of CD34 cells /kg needed on the same day of PBPC collection; and (3) PBPC collection in pediatric patients <10 kg body weight (as low as 5.8 kg body weight). J. Clin. Apheresis 2006. © 2006 Wiley-Liss, Inc. [source] Product Yield and Gaping in Cold-smoked Atlantic Salmon (Salmo salar) Fillets as Influenced by Different Injection-salting TechniquesJOURNAL OF FOOD SCIENCE, Issue 5 2003S. Birkeland ABSTRACT Product yield and fillet gaping severity were determined in cold-smoked Atlantic salmon fillets subjected to injection-salting. Effects of process parameter settings (brine injection pressure, number of repeated injections, needle speed, injection of brine in 1 or 2 directions, and chilled fillet resting before smoking) were tested. Repeated injections increased the yield up to 5.3% (wt/wt). Increasing injection pressure significantly increased the severity of fillet gaping in smoked fillets by 18%. Brine injection directions or needle speed did not affect smoking yield. The stability of the injection system was high. The results show that choice of process parameter settings during injection-salting affects product yield after smoking. [source] Process intensification using a two-phase system and micromixing for consecutive and reversible reactionsAICHE JOURNAL, Issue 6 2009Yoshihito Okubo Abstract This study aimed to find reaction conditions that improve the yield of target intermediate products, using a two-phase system and a microspace for first-order consecutive and reversible reactions. As a result, the yield of target products with a two-phase system can be surpassed by that of a single-phase system through selecting the organic phase such that the partition coefficient of the raw material to the aqueous phase is large, and that of the target product to the organic phase is also large. In addition, the volume ratio of two phases and the liquid,liquid interfacial area are also important factors for improving the target product yield. In a microspace, the microfluid segments can be designed both arbitrarily and precisely, and thus it is possible to control the interfacial area and mass transfer rates accurately. Utilization of a microspace can play a significant role in intensifying a two-phase system. © 2009 American Institute of Chemical Engineers AIChE J, 2009 [source] Geometric design of fluid segments in microreactors using dimensionless numbersAICHE JOURNAL, Issue 4 2006Nobuaki Aoki Abstract In microreactors, reactant fluids are split into many fluid segments and then fed into the reactors to shorten mixing time. Two dimensionless numbers are introduced to represent effects of geometric design factors of fluid segments, such as shapes and arrangements, on reactor performance, namely mixing rate and product yield and selectivity: the ratio of reaction rate to diffusion rate and the aspect ratio of the mean diffusion length in the two-dimensional (2-D) directions in the reactor cross section. Methods to determine these numbers are also proposed. To examine the validity of these numbers on estimating the reactor performance, we compare product yields between each pair of reactors having the different geometric design factors but the same dimensionless numbers using computational fluid dynamics simulations. The results show that these numbers serve as the indices for estimating the reactor performance. Using these numbers, design guidelines for geometry of fluid segments are also discussed. © 2005 American Institute of Chemical Engineers AIChE J, 2006 [source] Identification of quantitative trait loci for growth and carcass composition in cattle,ANIMAL GENETICS, Issue 1 2004E. Casas Summary A genomic screening to detect quantitative trait loci (QTL) affecting growth, carcass composition and meat quality traits was pursued. Two hundred nineteen microsatellite markers were genotyped on 176 of 620 (28%) progeny from a Brahman × Angus sire mated to mostly MARC III dams. Selective genotyping, based on retail product yield (%) and fat yield (%), was used to select individuals to be genotyped. Traits included in the study were birth weight (kg), hot carcass weight (kg), retail product yield, fat yield, marbling score (400 = slight00 and 500 = small00), USDA yield grade, and estimated kidney, heart and pelvic fat (%). The QTL were classified as significant when the expected number of false positives (ENFP) was less than 0.05 (F -statistic greater than 17.3), and suggestive when the ENFP was <1 (F -statistic between 10.2 and 17.3). A significant QTL (F = 19; ENFP = 0.02) was detected for marbling score at centimorgan (cM) 54 on chromosome 2. Suggestive QTL were detected for fat yield at 50 cM, for retail product yield at 53 cM, and for USDA yield grade at 63 cM on chromosome 1, for marbling score at 56 cM, for retail product yield at 70 cM, and for estimated kidney, heart and pelvic fat at 79 cM on chromosome 3, for marbling score at 44 cM, for hot carcass weight at 49 cM, and for estimated kidney, heart and pelvic fat at 62 cM on chromosome 16, and for fat yield at 35 cM on chromosome 17. Two suggestive QTL for birth weight were identified, one at 12 cM on chromosome 20 and the other at 56 cM on chromosome 21. An additional suggestive QTL was detected for retail product yield, for fat yield, and for USDA yield grade at 26 cM on chromosome 26. Results presented here represent the initial search for quantitative trait loci in this family. Validation of detected QTL in other populations will be necessary. [source] The study of fluidization fast pyrolysis of straw based on the biomass entrained flow gasificationASIA-PACIFIC JOURNAL OF CHEMICAL ENGINEERING, Issue 5 2009Dong Li Abstract Straw is considered to be a kind of low heating value biomass. A new entrained flow gasification process to utilize the straw was proposed and introduced fast pyrolysis as a straw pre-treatment unit for biomass entrained flow gasification process. This study was focused on the key factors influencing on the pyrolysis products of straw and optimized the pyrolysis condition based on the analysis results to meet the needs for biomass entrained flow gasification. Experiments were carried out at the temperature ranged from 300 to 600°C. Under certain particle size and optimized fluidization flow, the maximum liquid product yield was 43.1% at the temperature of 400°C and the maximum solid product yield was 65.6% at the temperature of 300°C. The characteristics of both liquid and solid products relevant to the gasification applications were analyzed. The results showed that the energy density of the products was far more higher than that of the crude straw. Finally, an optimal pyrolysis condition was proposed, which was considered to be a suitable feedstock solution for the biomass-slurry entrained flow gasification. Copyright © 2009 Curtin University of Technology and John Wiley & Sons, Ltd. [source] An integrated simultaneous distillation,extraction apparatus for the extraction of essential oils from herb materials and its application in Flos MagnoliaeBIOMEDICAL CHROMATOGRAPHY, Issue 3 2010Yuhui Wei Abstract A large number of herb materials contain essential oils with extensive bioactivities. In this work, an integrated simultaneous distillation,extraction (ISDE) apparatus was developed. To demonstrate its feasibility, the performance of ISDE was evaluated for the extraction of essential oil from Flos Magnoliae and compared with conventional techniques including steam distillation (SD) and simultaneous distillation,extraction (SDE). According to the product yield, the time consumed and the composition of oil, the essential oils isolated by ISDE were better than that obtained by SD and similar to those obtained by SDE. ISDE was also better than SDE due to its simple operation and lower consumption of energy and organic solvent. Copyright © 2009 John Wiley & Sons, Ltd. [source] Modeling the competition between aggregation and self-assembly during virus-like particle processing,BIOTECHNOLOGY & BIOENGINEERING, Issue 3 2010Yong Ding Abstract Understanding and controlling aggregation is an essential aspect in the development of pharmaceutical proteins to improve product yield, potency and quality consistency. Even a minute quantity of aggregates may be reactogenic and can render the final product unusable. Self-assembly processing of virus-like particles (VLPs) is an efficient method to quicken the delivery of safe and efficacious vaccines to the market at low cost. VLP production, as with the manufacture of many biotherapeutics, is susceptible to aggregation, which may be minimized through the use of accurate and practical mathematical models. However, existing models for virus assembly are idealized, and do not predict the non-native aggregation behavior of self-assembling viral subunits in a tractable nor useful way. Here we present a mechanistic mathematical model describing VLP self-assembly that accounts for partitioning of reactive subunits between the correct and aggregation pathways. Our results show that unproductive aggregation causes up to 38% product loss by competing favorably with the productive nucleation of self-assembling subunits, therefore limiting the availability of nuclei for subsequent capsid growth. The protein subunit aggregation reaction exhibits an apparent second-order concentration dependence, suggesting a dimerization-controlled agglomeration pathway. Despite the plethora of possible assembly intermediates and aggregation pathways, protein aggregation behavior may be predicted by a relatively simple yet realistic model. More importantly, we have shown that our bioengineering model is amenable to different reactor formats, thus opening the way to rational scale-up strategies for products that comprise biomolecular assemblies. Biotechnol. Bioeng. 2010;107: 550,560. © 2010 Wiley Periodicals, Inc. [source] Ultra scale-down prediction using microwell technology of the industrial scale clarification characteristics by centrifugation of mammalian cell brothsBIOTECHNOLOGY & BIOENGINEERING, Issue 2 2009A.S. Tait Abstract This article describes how a combination of an ultra scale-down (USD) shear device feeding a microwell centrifugation plate may be used to provide a prediction of how mammalian cell broth will clarify at scale. In particular a method is described that is inherently adaptable to a robotic platform and may be used to predict how the flow rate and capacity (equivalent settling area) of a centrifuge and the choice of feed zone configuration may affect the solids carry over in the supernatant. This is an important consideration as the extent of solids carry over will determine the required size and lifetime of a subsequent filtration stage or the passage of fine particulates and colloidal material affecting the performance and lifetime of chromatography stages. The extent of solids removal observed in individual wells of a microwell plate during centrifugation is shown to correlate with the vertical and horizontal location of the well on the plate. Geometric adjustments to the evaluation of the equivalent settling area of individual wells (,M) results in an improved prediction of solids removal as a function of centrifuge capacity. The USD centrifuge settling characteristics need to be as for a range of equivalent flow rates as may be experienced at an industrial scale for a machine of different shear characteristics in the entry feed zone. This was shown to be achievable with two microwell-plate based measurements and the use of varying fill volumes in the microwells to allow the rapid study of a fivefold range of equivalent flow rates (i.e., at full scale for a particular industrial centrifuge) and the effect of a range of feed configurations. The microwell based USD method was used to examine the recovery of CHO-S cells, prepared in a 5,L reactor, at different points of growth and for different levels of exposure to shear post reactor. The combination of particle size distribution measurements of the cells before and after shear and the effect of shear on the solids remaining after centrifugation rate provide insight into the state of the cells throughout the fermentation and the ease with which they and accumulated debris may be removed by continuous centrifugation. Hence bioprocess data are more readily available to help better integrate cell culture and cell removal stages and resolve key bioprocess design issues such as choice of time of harvesting and the impact on product yield and contaminant carry over. Operation at microwell scale allows data acquisition and bioprocess understanding over a wide range of operating conditions that might not normally be achieved during bioprocess development. Biotechnol. Bioeng. 2009; 104: 321,331 © 2009 Wiley Periodicals, Inc. [source] Biotransformation of R -2-hydroxy-4-phenylbutyric acid by D -lactate dehydrogenase and Candida boidinii cells containing formate dehydrogenase coimmobilized in a fibrous bed bioreactorBIOTECHNOLOGY & BIOENGINEERING, Issue 2 2005Yunling Bai Abstract R -2-hydroxy-4-phenylbutyric acid (R-HPBA) is an important intermediate in the manufacture of angiotensin converting enzyme inhibitors. In this work, a recombinant D -lactate dehydrogenase (LDH) was used to transform 2-oxo-4-phenylbutyric acid (OPBA) to R-HPBA, with concomitant oxidation of ,-nicotinamide adenine dinucleotide (NADH) to NAD+. The cofactor NADH was regenerated by formate dehydrogenase (FDH) present in whole cells of Candida boidinii, which were pre-treated with toluene to make them permeable. The whole cells used in the process were more stable and easier to prepare as compared with the isolated FDH from the cells. Kinetic study showed that the reaction rate was dependent on the concentration of cofactor, NAD+, and that both R-HPBA and OPBA inhibited the reaction. A novel method for co-immobilization of whole cells and LDH enzyme on cotton cloth was developed using polyethyleneimine (PEI), which induced the formation of PEI,enzyme,cell aggregates and their adsorption onto cotton cloth, leading to multilayer co-immobilization of cells and enzyme with high loading (0.5 g cell and 8 mg LDH per gram of cotton cloth) and activity yield (,>,95%). A fibrous bed bioreactor with co-immobilized cells and enzyme on the cotton cloth was then evaluated for R-HPBA production in fed-batch and repeated batch modes, which gave relatively stable reactor productivity of 9 g/L,·,h and product yield of 0.95 mol/mol OPBA when the concentrations of OPBA and R-HPBA were less than 10 g/L. © 2005 Wiley Periodicals, Inc. [source] | |||||||||||||||||||||||||||||||||||||||||||