Mika Kähkönen Department of Applied Chemistry and Microbiology 25.10.2007, HERC Seminar HYDROLYTIC AND LIGNINOLYTIC ENZYME ACTIVITIES IN THE Pb CONTAMINATED SOIL
Introduction Pb is deleterious to soil microbial processes Pb is neurotoxic agent amount of shooting ranges in Finland is 2000-2500 abundant biopolymers in nature are cellulose, hemicellulose and lignin Hydrolytic enzymes ligninolytic enzymes
THE AIMS 1. To test the effect of Pb contamination on hydrolytic and ligninolytic enzyme activity in the forest soil. 2. To test the ability of litter-degrading fungi to grow and produce extracellular enzymes in the heavily Pb (40 g Pb of kg ww soil-1 ) contaminated soil and non contaminated soil in non sterile conditions was also tested
Materials and Methods Soil: -humus layer - sampled close to a shooting range in Hollola Soil plate experiments: wihout Pb with Pb without fungi .with fungi (Agaricus bisporus, Agrocybe praecox, Gymnopus peronatus, Gymnopilus penetrans, Mycena galericulata, Gymnopilus luteofolius, Stropharia aeruginosa and Stropharia rugosoannulata).
Enzyme activity measurements • hydrolytic enzyme activities • ligninolytic enzyme activities
Conclusions The Pb contamination (40 g Pb of kg ww soil-1 ) was deleterious to all five studied hydrolytic enzyme activities Hydrolytic enzyme activities were significantly higher in the soil than in the extract of the soil Hydrolytic enzyme activities were similar with fungi and without fungi in the Pb contaminated soil. Pb contamination (40 g Pb of kg ww soil-1) depressed the growth of all fungi The best grown fungi was S. rugosoannulata, which had the highest MnP and laccase activities in the non contaminated soil.