| | 1 | Author
| Gerold Baier, Peter Urban, Klaus Wegmann | Requires cookie* | | | Title
| A  | | | | Abstract
| N e w M o d e l S y s te m fo r th e S tu d y o f C o m p le x D y n a m ic a l E n z y m e R e a c tio n s . I. A N o n lin e a r E n z y m e R e a c tio n in a C h e m ic a l G r a d ie n t An experimental system for the study of biochemical reaction dynamics is introduced and de scribed. A one-enzyme reaction is extended by an artificial feedback loop in an electrochemical device. Cyclic voltammetry is used to show that the reaction rate depends nonlinearly on the amount of cosubstrate offered. For some sets of fixed parameter values a damped oscillatory approach of the steady state was observed. The usefulness of the systems theoretical concepts is discussed. | | | |
Reference
| Z. Naturforsch. 43a, 987—994 (1988); Received August 22 1988 | | | |
Published
| 1988 | | | |
Keywords
| Reaction-diffusion Systems, Peroxidase, Feedback, Nonlinearity, Damped Oscillations | | | |
Similar Items
| Find | | | DEBUG INFO
| | | | | TEI-XML for
| default:Reihe_A/43/ZNA-1988-43a-0987.pdf | | | | Identifier
| ZNA-1988-43a-0987 | | | | Volume
| 43 | |
| 3 | Author
| Martin Patzlaff, W. Olfgang Barz | Requires cookie* | | | Title
| Peroxidatic Degradation of Flavanones | | | | Abstract
| Peroxidases were shown to be responsible for the degradation of flavanones as occuring after application of these substrates to plant cell suspension cultures. — Com parative studies with various flavanones and horseradish peroxidase showed th at only 4'-hydroxyflavanones will be catabolized peroxidatically. — Intensive analyses of naringenin (5,7,4'-trihydroxyflavanone) de gradation by horseradish peroxidase revealed that very complex reactions with m any catabolites are involved. Main degradative pathways comprise a) hydroxilation in the 3'-position, b) elim ina tion of ring B leading to chromones, c) cleavage reactions of the heterocylic ring resulting in phenolic catabolites from ring A and most im portant d) oxidative destruction of ring A leading to Cg — Cg-, Cs —C2-and C6—Cj-units from ring B. — The data are com pared with the results of feeding experiments and are discussed with regard to th eir physiological significance. | | | |
Reference
| Z. Naturforsch. 33c, 675 (1978); received July 3 1978 | | | |
Published
| 1978 | | | |
Keywords
| Flavanones, Catabolites, Peroxidases, D egradation, Substitution Pattern | | | |
Similar Items
| Find | | | DEBUG INFO
| | | | | TEI-XML for
| default:Reihe_C/33/ZNC-1978-33c-0675.pdf | | | | Identifier
| ZNC-1978-33c-0675 | | | | Volume
| 33 | |
| 4 | Author
| Regina Volpert, ErichF. Elstner | Requires cookie* | | | Title
| Biochemical Activities of Propolis Extracts I. Standardization and Antioxidative Properties of Ethanolic and Aqueous Derivatives | | | | Abstract
| Ethanolic extracts of Propolis are used as antiinflammatory and wound healing drugs since ancient times. In order to facilitate a comparison of different extracts, the standardization on the basis of quantitative determination of prominent components of these extracts has been substituted for simple biochemical "activity" tests. One of these activity tests bases on the in hibition of peroxidase-catalyzed oxidation of indole acetic acid indicating the presence of a defined mixture of monophenolic and diphenolic compounds. Other tests (diaphorase-cata-lyzed reductions and xanthine oxidase-catalyzed oxidations) demonstrate significant radical scavenging properties. Water-soluble extracts of propolis exhibit higher antioxidative and inhibitory activities as compared to the ethanolic extract. | | | |
Reference
| Z. Naturforsch. 48c, 851—857 (1993); received June 21/August 161993 | | | |
Published
| 1993 | | | |
Keywords
| Propolis, Peroxidase, Xanthine Oxidase, Diaphorase, Indole Acetic Acid Oxidation | | | |
Similar Items
| Find | | | DEBUG INFO
| | | | | TEI-XML for
| default:Reihe_C/48/ZNC-1993-48c-0851.pdf | | | | Identifier
| ZNC-1993-48c-0851 | | | | Volume
| 48 | |
| 6 | Author
| Wolfgang Barz, Rita Schlepphorst, Peter Wilhelm, Westfalen, Karl Kratzl, Erich Tengler | Requires cookie* | | | Title
| Metabolism of Benzoic Acids and Phenols in Cell Suspension Cultures of Soybean and Mung Bean | | | | Abstract
| Uptake of benzoic and salicylic acid by soybean cell suspension cultures is diffusion-mediated and exclusively leads to glucose-esters. — Veratric acid is para-demethylated to vanillic acid which is conjugated to a monoglucoside. — Nitrobenzoic acids are scarcely taken up by cell cultures with glucose-esters as sole products. — Ring-labelled derivatives of vanillylalcohol and creosol are mainly polymerized to insoluble structures, ring cleavage reactions could not be observed. | | | |
Reference
| Z. Naturforsch. 33c, 363 (1978); received April 12 1978 | | | |
Published
| 1978 | | | |
Keywords
| Benzoic Acids, Phenols, Ring Fission, Peroxidases, Polymerisation, Plant Cell Suspension Cultures | | | |
Similar Items
| Find | | | DEBUG INFO
| | | | | TEI-XML for
| default:Reihe_C/33/ZNC-1978-33c-0363.pdf | | | | Identifier
| ZNC-1978-33c-0363 | | | | Volume
| 33 | |
| 8 | Author
| Ralf Perrey, Marie-Theres Hauser, MichaelW. Ink | Requires cookie* | | | Title
| Cellular and Subcellular Localization of Peroxidase Isoenzymes in Plants and Cell Suspension Cultures from Lupinus polyphyllus | | | | Abstract
| , leaf protoplasts and cell suspension cultures of Lupinus polyphyllus and isolated vacuoles were studied for cellular and subcellular localization of peroxidase isoenzymes. Isoelectric focusing revealed 16 peroxidase isoenzymes. The basic peroxidase isoenzymes are predominantly localized in the vacuole and, to a minor degree, unbound in the intercellular space. The acidic isoenzymes are cell wall-bound in plants and not detectable in suspension-cultured cells. Large amounts (up to 11.0 U/ml) of a single basic isoenzyme are detectable in the spent medium of cell suspension cultures. | | | |
Reference
| Z. Naturforsch. 44c, 931—936 (1989); received August 4 1989 | | | |
Published
| 1989 | | | |
Keywords
| Lupinus, Peroxidase, Localization, Isoelectric Focusing (Peroxidase), Cell Culture Leaves, stems, roots | | | |
Similar Items
| Find | | | DEBUG INFO
| | | | | TEI-XML for
| default:Reihe_C/44/ZNC-1989-44c-0931.pdf | | | | Identifier
| ZNC-1989-44c-0931 | | | | Volume
| 44 | |
|
