Abstract
The model substrate L-dihydroxy phenylalanine (L-DOPA) was used to measure the activity of phenol-oxidase (PO) in peat from a Welsh riparian wetland. The sensitive and relatively simple technique measured the rate of formation of the red coloured compound 2-carboxy-2,3-dihydroindole-5,6-quinone from the enzymic oxidation of L-dopa. The method was used to test the hypothesis that the large exports of phenolic materials from peatlands into aquatic systems were caused by low phenolic-degrading enzyme activities within the peat matrix. The low oxygen availability and acidic pH of the peat soil were found to be sub-optimal for PO activity. Furthermore, a depth-dependent decline in PO activity was inversely correlated with phenolic concentrations. Thus, the findings supported the above hypothesis.
Article PDF
Similar content being viewed by others
Avoid common mistakes on your manuscript.
References
Appel H M 1993 Phenolics in ecological interactions: the importance of oxidation. J. Chem. Ecol. 19, 1521–1553.
Box J D 1983 Investigation of the Folin-Ciocalteau Phenol reagent for the determination of polyphenolic substances in natural waters. Water Res. 17, 249–261.
Burns R G 1978 Soil enzymes. Academic Press, London, UK.
Canicatti C and Seymour J 1991 Evidence for Phenol oxidase activity in Holothuria tubulosa (Echinodermata) Brown bodies and cells. Parasitol. Res. 77, 50–53.
Clymo R S and Reddaway E J F 1971 Productivity of sphagnum (bog-moss) and peat accumulation. Hidrobiologia 12, 181–192.
Dickinson C H 1979 Microorganisms in Peatlands. In Ecosystems of the world 4A. Ed. A J P Gore. pp 225–243. Elsevier, Amsterdam, The Netherlands.
Freeman C, Lock M A, Marxsen J and Jones S E 1990 Inhibitory effects of high molecular weight dissolved organic matter upon the metabolic processes in biofilms from contrasting rivers and streams. Freshwat. Biol. 24, 159–166.
Gafni A and Brooks K N 1990 Hydraulic characteristics of four peatlands in Minnesota. Can. J. Soil Sci. 70, 239–253.
Gammelgaard A, Freeman C and Lock M A 1992 Measurement of electron transport system activity in sphagnum derived peat. Soil Biol. Biochem. 25, 505–507.
Goulder R 1990 Extracellular enzyme activities associated with epiphytic microbiota on submerged steams of the red Phragmites australis. Microb. Ecol. 73, 323–330.
Ladd J N 1985 Soil enzymes. In Soil organic matter and biological activity. Advances in Plant and Soil Science (vol. 16), Eds. D Vaughan and R E Malcolm. pp 175–221. Nijhoff/Junk Publishers, Dordrecht, The Netherlands.
Marxsen J and Witzel K P 1990 Measurement of exoenzymatic activity in streambed sediments using methylumbelliferyl-substrates. Arch Hydrobiol. Beih. 34, 21–28.
Mason H S 1948 The chemistry of melanin III. Mechanism of the oxidation of dihydroxyphenylalanine by tyrosinase. J. Biol. Chem. 172, 83–99.
Moore P D and Bellamy D J 1974 Peatlands. Elek Science, London, UK, pp 84–117.
Pomerantz S H and Li J P 1970 Tyrosinases. Methods Enzymol. 17a, 620–621.
Sikora L J and Keeney D R 1977 Further aspects of soil chemistry under Anaerobic conditions. In Ecosystems of the world 4A. Ed. A J P Gore. pp 247–256. Elsevier, Amsterdam, The Netherlands.
Sinsabaugh R L and Linkins A E 1988 Enzyme activity associated with lotic epilithon. Freshwat. Biol. 20, 249–261.
Sinsabaugh R L and Linkins A E 1990 Enzymatic and chemical analysis of particulate organic matter from a Boreal river. Freshwat. Biol. 23, 301–309.
Stewart A J and Wetzel R G 1982 Influence of dissolved humic materials on carbon assimilation and alkaline phosphatase activity in natural algal-bacterial assemblages. Freshwat. Biol. 12, 369–380.
Wetzel R G 1992 Gradient dominated ecosystems: Sources and regulatory functions of dissolved organic matter in freshwater ecosystems. Hydrobiologia 229, 181–198.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Pind, A., Freeman, C. & Lock, M.A. Enzymic degradation of phenolic materials in peatlands — measurement of phenol oxidase activity. Plant Soil 159, 227–231 (1994). https://doi.org/10.1007/BF00009285
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF00009285