Thermal inactivation of native and crosslinked invertases

1997-09-01
Kaplan, O
Bakir, U
Erarslan, A
Formaldehyde and three homobifunctional bisimidoesters having different lengths, dimethyl suberimidate (DMS), dimethyl adipimidate (DMA), dimethyl-3,3'-dithiobispropionimidate (DTBP), were used to crosslink invertase. Optimal concentrations for crosslinking with DMS and formaldehyde were determined as 0.3% and 0.015%, respectively. Inactivation mechanisms of the native, DMS and formaldehyde cross-linked invertases were first order during prolonged heat treatment. The maximum stabilization factors with DMS and formaldehyde were 1.5 at 55 degrees C and 1.7 at 57.5 degrees C, respectively. V-max and K-m values decreased 5 to 10% by DMS and formaldehyde crosslinking. On the other hand, crosslinking with DMA and DTBP decreased stability against inactivation.
BIOTECHNOLOGY TECHNIQUES

Suggestions

Conducting polymer composites: Polypyrrole and poly(vinyl chloride vinyl acetate) copolymer
Balci, N; Bayramli, E; Toppare, Levent Kamil (Wiley, 1997-04-25)
Composites of a polypyrrole (PPy) and poly(vinyl chloride-vinyl acetate) copolymer (PVC-PVA) were prepared both chemically and electrochemically. An insulating polymer was retained in the blend and the thermal stability of the polymer was enhanced by polymerizing pyrrole into the host matrix in both cases. The composites prepared electrochemically gave the best results in terms of conductivity and air stability. (C) 1997 John Wiley & Sons, Inc.
Enantioselective synthesis of 2-(2-arylcyclopropyl)glycines: Conformationally restricted homophenylalanine analogs
Demir, Ayhan Sıtkı; Sesenoglu, O; Ulku, D; Arici, C (Wiley, 2004-01-01)
Starting from simple aromatic aldehydes and acetylfuran, (E)-1-(furan-2-yl)-3-arylprop-2-en-1-ones (2) were synthesized in high yields. Cyclopropanation of the C=C bond with trimethylsulfoxonium iodide (Me3SO+I-) furnished (furan-2-yl)(2-arylcyclopropyl)methanones 3 in 90-97% yields. Selective conversion of cyclopropyl ketones to their (E)- and (Z)-oxime ethers 5 and oxazaborolidine-catalyzed stercoselective reduction of the C-N bond followed by separation of the formed diastereoisomers, furnished (2-arylcy...
Asymmetric synthesis of novel 1,4-aminoalcohol ligands with norbornene and norbornane backbone: use in the asymmetric diethylzinc addition to benzaldehyde
Tanyeli, Cihangir; ERDEM, Mine; ÇAKIR, Esen; KESKİN, Eda (Elsevier BV, 2007-09-27)
The asymmetric synthesis of cis-1,4-aminoalcohols with norbornene and norbornane backbone was performed starting with (2S, 3R)-(-)-cis-hemiester 1 (98% ee). Chemoselective amination with HMPTA followed by Grignard reactions and subsequent LAH reductions afforded compounds 5a-d. cis-Hemiester 1 was also transformed into chiral ligands 7a-f and 9a-d with the DCC coupling method followed by LAH reduction using acyclic, heterocyclic amines and various aniline derivatives and p-toluenesulfonamide, respectively. ...
Reactive processing of styrene-maleic anhydride and epoxy functionalized polymer blends
Bayram, G; Yılmazer, Ülkü; Xanthos, M (1999-05-06)
The reaction of styrene-maleic anhydride (SMA) with polyethylene/methyl acrylate/glycidyl methacrylate (E-MA-GMA) was studied in a batch mixer and in a corotating twin screw extruder. Also, the mixing of a nonreactive blend of SMA with polyethylene/methyl acrylate (E-MA), with similar rheological properties to E-MAG-MA, was studied under the same processing conditions. The mixing products of reactive and nonreactive systems exhibited drastically different properties. Reactive blends showed higher tensile mo...
Osmium(0) nanoclusters stabilized by zeolite framework; highly active catalyst in the aerobic oxidation of alcohols under mild conditions
Zahmakiran, Mehmet; Akbayrak, Serdar; Kodaira, Tetsuya; Özkar, Saim (Royal Society of Chemistry (RSC), 2010-08-01)
Osmium(0) nanoclusters stabilized by zeolite-Y framework were reproducibly prepared by a simple two step procedure involving the incorporation of osmium(III) canons into the zeolite matrix by ion-exchange, followed by their reduction within the cavities of zeolite with sodium borohydride in aqueous solution all at room temperature. The composition and morphology of osmium(0) nanoclusters stabilized by zeolite framework, as well as the integrity and crystallinity of the host material were investigated by usi...
Citation Formats
O. Kaplan, U. Bakir, and A. Erarslan, “Thermal inactivation of native and crosslinked invertases,” BIOTECHNOLOGY TECHNIQUES, pp. 621–623, 1997, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/67232.