Showing papers in "Enzyme and Microbial Technology in 1993"

TL;DR: By using a model industrial enzyme, beta-galactosidase from Aspergillus oryzae, the excellent prospects of MANA-agarose gels, which contain primary amino groups with a very low pK value, are demonstrated.

TL;DR: The use of enzymes in the synthesis and modification of optically pure drugs is reviewed, with special attention on the synthesis of new pharmaceuticals which may require efficient procedures for large-scale synthesis in the future.

TL;DR: Values for E and the thermodynamic equilibrium constant, KEQ, were obtained for a (DL)-dehalogenase-catalyzed dehalogenation, a hydrolysis reaction by porcine pancreatic lipase, and for Cylindracea lipase-Catalyzed esterification and transesterification.

TL;DR: Its stability over a range of alkaline pH and temperature and its compatibility with commercial detergents was determined, and the enzyme was most stable between pH 6.0–8.5 and at temperatures up to 40°C.

TL;DR: The evidence available favors a model in which conidial bound cellobiohydrolases carry out a first exo-exo-wise attack on the cellulose molecule, and evidence available suggests that they are further metabolized to, rather than being, the "true" inducer.

TL;DR: The nature of substrates on which acetyl xylan esterase, feruloyl, and p-coumaroyl esterases are active and their role in xylan hydrolysis is emphasized and their significance to applied microbiology is discussed.

TL;DR: The use of thermoprecipitating polymer-protein conjugates in immunoassays overcomes one of the shortcomings of traditional methods with solid sorbent-linked antigen or antibody-diffusional limitations.

TL;DR: An overview of the state of the art through examples chosen from the most recent literature is offered, focusing mainly on the preparation of enantiomerically pure products which can be formed by this enzymatic approach.

TL;DR: The occurrence, regulation, and action of fungal enzymes capable of degrading noncellulosic β-glucans, especially 1,3-β- and 1,6-β, are reviewed, with some of the properties of purified β- glucanases discussed in terms of their potential applications in industrial, agricultural, and medical fields.

TL;DR: Findings indicate the existence of enzymes in K. pneumoniae that transfer reducing equivalents from NADH2 to H2 and 1,3-propanediol flexibility, and the physiological meanings of these regulatory mechanisms are discussed from the viewpoint of bioenergetics and product inhibition.

TL;DR: A comparison is made between the amino acid sequences of the various lipases as well as their secondary gene products, which are thought to be essential for secretion of the enzyme.

TL;DR: The enzymatic hydrolysis of cellulose was initially investigated using the alkaline peroxide-treated fraction derived from steam-exploded Eucalyptus viminalis chips and a cellulase mixture of the commercial Celluclast and Novozym preparations and most of the cellulase activity was shown to be associated with the undydrolyzed residue.

TL;DR: Extracellular lipase was produced by the solvent-resistant strain Pseudomonas putida 3SK during the late logarithmic growth phase and was purified 21-fold with 5.3% recovery by ion exchange chromatography and gel filtration chromatography.

TL;DR: In this paper, the half-life of a dry enzyme in supercritical carbon dioxide (SCCO2) at 100°C was about 24 hours and the effect of ester chain length on the rate of reaction was investigated.

TL;DR: The xylanase of T. lanuginosus was found to be inducible by xylan containing C sources as well as by xylose, and the optimal pH values of all enzymes were determined.

TL;DR: In this article, the action of Trichoderma cellulases on the various characteristics of cellulosic fractions obtained from pretreated eucalyptus chips was investigated, and a screened fraction derived from a fully bleached kraft pulp (FBEP-48 fraction) was shown to consist of fibers with an average fiber length and an average degree of polymerization (DP) considerably higher than that obtained for the screened fraction obtained from SO2-impregnated steam-exploded EucalyPTus chips which had been post-treated with alkaline hydrogen peroxide

TL;DR: Maintenance and growth of Methanosarcinae -dominated granules under different Mg 2+ concentrations (0–100 m m) were investigated in 0.2-l acetate-fed UASB reactors at 55°C, giving rise to fluffy granules consisting mainly of rod-shaped methanogens.

TL;DR: A novel oxidoreductase catalyzing the NADH-dependent reduction of a variety of carbonyl compounds, especially keto esters, was found in Candida parapsilosis DSM 70125 and methyl 3-oxobutanoate was converted into methyl (S)-(+)-3-hydroxybutanoate, a versatile chiral building block for the synthesis of pheromones and different antibiotics.

TL;DR: The results strongly suggest that the soluble lipase could exist in different aggregation forms depending on the pH of the medium, and at acidic pH, the relative proportion of high-molecular-weight forms of the enzyme is higher than at pH 7.0, suggesting that the lipase would be also immobilized in different aggregating forms dependingon the pH used in the immobilization procedure.

TL;DR: Immobilized C. cylindracea preparations were more active when hexane was used as the reaction medium, and anion-exchange resin was a better support than diatomaceous earth, and Hexane was also a better immobilization medium for A. niger lipase.

TL;DR: This review article describes aspects and the proposals that have been made in recent years concerning two-liquid-phase bioreactors and shows some adaptations to existing bioreACTors, such as loop reactors and stirred-tank reactors.

TL;DR: It is found that d -tagatose can be produced from d -galactose by the lactic acid bacterium Lactobacillus gayonii, and this bioconversion of a d -hexose sugar is probably carried out by an l -pentose isomerase enzyme activity of the cells.

TL;DR: A comparison between both classes of mutants, called A W96 and AW99, respectively, points to the need to design special selective nrrdia in order to obtain strains adapted either to SSF or SmF in which the level of water activity would be a key selecring factor.

TL;DR: Among various microbial cultures evaluated, cell suspensions of Acinetobacter calcoaceticus SC 13876 reduced 1 to 2a by the stereoselective microbial reduction of 3,5-dioxo-6-(benzyloxy) hexanoic acid, ethyl ester 1.

TL;DR: Activity was higher when the organism was grown on carboxymethylcellulose and xylan than on other soluble substrates and catabolite repression of xylanase activity occurred when glucose, cellobiose, and other readily metabolizable substrates were added during growth on CMC.

TL;DR: In this paper, a literature survey is presented on the effects of hydrodynamic stress (shear stress) on cultured plant cells, which can be designated as "damage" and various symptoms of cell damage as damage indicator are discussed.

TL;DR: A culture medium for a wild strain of Schizophyllum commune was optimized with regard to xylanase production by means of response surface methods and included microcrystalline cellulose, yeast extract, and NH 4 NO 3.

TL;DR: Structural and catalytic properties of two enzymes--alpha-chymotrypsin and horse liver alcohol dehydrogenase (LADH)--are studied in bis(2-ethylhexyl) sodium sulfosuccinate (AOT)-isooctane reverse-micelle solutions to explain the observed activity of these two enzymes in reverse micelles.

TL;DR: In this article, the reverse micelles around the Celite-immobilized and hydrated enzyme that protected the enzyme from the nonpolar solvent and enhanced substrate and product diffusion in the enzyme microenvironment.

TL;DR: Ethanol production through simultaneous saccharification and fermentation (SSF) is discussed, in which paper mill waste fiber from the ammonium sulfite pulp process was used and the maximum ethanol concentration was obtained.