The effect of physico-chemical parameters and chemical compounds on the activity of beta-d-galactosidase (B-GAL), a marker enzyme for indicator microorganisms in water
| Autor: | Victor Collins Wutor, Chamunorwa Togo, Brett I. Pletschke |
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| Rok vydání: | 2006 |
| Předmět: |
Environmental Engineering
Coumaric Acids Sodium Hypochlorite Health Toxicology and Mutagenesis Carbonates Citric Acid chemistry.chemical_compound Hydrolysis Chlorides Enterobacteriaceae Environmental Chemistry Water Pollutants Chlorophenol red Edetic Acid Chlorophenol chemistry.chemical_classification Chromatography Nitrates biology Chromogenic Sulfates Public Health Environmental and Occupational Health Temperature Galactosides General Medicine General Chemistry Hydrogen-Ion Concentration beta-Galactosidase Pollution Enzyme assay Enzyme chemistry Biochemistry Metals Sodium hypochlorite biology.protein Water treatment Water Microbiology Biomarkers Chlorophenols Environmental Monitoring |
| Zdroj: | Chemosphere. 68(4) |
| ISSN: | 0045-6535 |
| Popis: | The presence of coliforms in polluted water was determined enzymatically (in situ) by directly monitoring the activity of beta-d-galactosidase (B-GAL) through the hydrolysis of the yellow chromogenic subtrate, chlorophenol red beta-d-galactopyranoside (CPRG), which produced a red chlorophenol red (CPR) product. The objectives of this study were to monitor the effect of compounds commonly found in the environment and used in water treatment on a B-GAL CPRG assay and to investigate the differences between the environmental B-GAL enzyme and the pure commercial enzyme. Environmental B-GAL was optimally active at pH 7.8. Two temperature optima were observed at 35 and 55 degrees C, respectively. B-GAL activity was strongly inhibited by silver and copper ions. While calcium and ferrous ions at lower concentrations (50-100mgl(-1)) increased the enzyme activity, a reduction was observed at higher concentrations (200mgl(-1)). Sodium hypochlorite, normally used in rural areas to disinfect water gradually decreased B-GAL activity at concentrations between 0 and 5600ppm for both the commercial and environmental enzymes. B-GAL from the environment behaved differently from its commercially available counterpart. |
| Databáze: | OpenAIRE |
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