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41.
A starter culture ofTrichoderma reesei (Rut-C30) prepared in a liquid fluidized bed reactor (LFBR) gave better growth and greater cellulase production in submerged
fermentation than a conventional shake flask inoculum. The LFBR starter was prepared by first coatingT. reesei spores to 0.25 mm size corncob (1.0x108g-1) in a medium containing 1.0% corncob, 0.5 gL-1 xylose and 0.1 gL-1 lactose in a balanced salt solution, then fluidizing the particles in the LFBR for 36 h to allow germination of the spores,
and covering the particles with an approx 30 μm thick biofilm. This biofilm that developed in constant adherence to the lignocellulosic
carrier, apparently became well adapted to grow rapidly on insoluble cellulose substrates (Solca Floc), and had the enzymes
of the cellulase complex induced for increased cellulase production.
The LFBR starter used in a stirred tank reactor (STR) gave 15 gL-1 biomass production and 6.5 IU mL-1 overall cellulase activity with a volumetric productivity of 64 IU L-1h-1 in a 5 d fermentation, compared with a 7 d shake flask inoculum that gave 11 gL-1 biomass and 3.2 IU mL-1 cellulase activity, with a volumetric productivity of 31IU L-1h-1. The LFBR starter culture retained its viability in dry storage for 6–9 mo. 相似文献
42.
A method for the quantification of total d-gluconate by flow-injection analysis was developed using an immobilized-enzyme reactor and fluorescence detection. d-Gluconate was quantified using co-immobilized gluconate kinase (GK) and 6-phosphogluconate dehydrogenase (PGDH) reactor. d-Gluconate was phosphorylated to 6-phospho-d-gluconate by GK in the presence of ATP, and then the 6-phospho-d-gluconate produced was oxidized by PGDH with NADP+. The NADPH produced by the GK-PGDH reactor was monitored fluorometrically at 455 nm (excitation at 340 nm). A linear relationship between the responses and concentrations of d-gluconate was obtained in the ranges of 1.0 × 10−6–1.6 × 10−4 M. The relative standard deviation for 10 successive injections was 0.57% at the 0.1 mM level. This analytical method was applied to the quantification of d-gluconate in honeys, vinegars and noble rot wines, and the results showed good agreement with those obtained using the conventional F-kit method. 相似文献
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A new simple, sensitive, rapid and precise flow injection (FI) procedure based on the formation of copper complexes with some angiotensin converting enzyme (ACE) inhibitors has been developed and evaluated for the analysis of lisinopril (LN), enalapril maleate (EP), ramipril (RP) and perindopril tert-butylamine (PD). In this method, samples were injected into a flowing stream of distilled-deionized water, carried through the packed reactor of CuO for derivatization followed by ultraviolet (UV) detection. The flow rate was 1.5 ml min−1 and column temperature was ambient (25 °C). Lisinopril was injected directly into the flowing stream and the detector response was measured at 262 nm. The hydrolysis products of enalapril maleate, ramipril and perindopril tert-butylamine in 0.2N NaOH were injected after neutralization with 1N HCl and the detector response was measured at 272, 265 and 252 nm, respectively. The developed method was successfully applied to the determination of tested drugs in pharmaceutical preparations at a sampling rate of 60 samples h−1 and a recovery near 100% for all compounds. 相似文献
46.
Summary Analytical peak-shape equations were derived for first-order reversible reactions occurring in a chromatographic reactor by
treating the reversible reactions as consecutive reactions with alternating products. The results of the analytical peak-shape
equations were compared with those from a numerical solution of the partial differential equation system modeling the chromatographic
reactor. For small to medium conversions the correspondence was found to be sufficiently close to enable substitution of the
numerical solution in fitting procedures for the determination of rate constants.
Presented at the 21st ISC held in Stuttgart, Germany, 15th–20th September, 1996 相似文献
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48.
Methane production from synthesis gas using a mixed culture ofR. rubrum M. barkeri,and M. formicicum
Klasson K. T. Cowger J. P. Ko C. W. Vega J. L. Clausen E. C. Gaddy J. L. 《Applied biochemistry and biotechnology》1990,(1):317-328
The components of synthesis gas, CO, H2, and CO2, may be converted into CH4 biologically through either acetate or H2/CO2 as intermediates. Of these two routes, conversion through H2/CO2 is preferred. This paper presents results of mixed-culture studies employing the photosynthetic bacteriumR. rubrum for converting CO to CO2 and H2 by the water gas shift reaction and two methanogens,M. formicicum andM. barkeri, for converting CO2 and H2 into CH4. Results are presented for triculture operation in two types of reactors, the packed bubble column and the trickle-bed reactor. 相似文献
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A laboratory system for the on-line monitoring of important lactic acid fermentation variables is described. The system contains flow-injection analysers for glucose, lactose, galactose, lactate and protein and a continuous-flow analyser for the biomass concentration. The sugar and lactate analysers are based on enzymatic reactions involving oxidases followed by chemiluminescence detection of the hydrogen peroxide formed. The protein analyser is based on the biuret reaction. The system has been used to monitor many fermentation experiments, and some results are presented as examples. 相似文献