Linking microbial genetic- and functional diversity in compost: DGGE-profiling separated different types of compost regarding chitinase activity

Summary in the original language of the document

Using denaturing gradient gel electrophoresis (DGGE) and simultaneously measure the enzymatic activity of chitinase, we could link genetic and functional diversity of the indigenous microbial communities in compost samples. Two types of compost, a garden/park waste compost (D-Gro A) and a source separated organic household waste compost (Biovækst), showed different genetic diversity as measured by PCR-DGGE of total DNA extracted from the composts. The composts also had different chitinase activity, 0.46 and 3.97 µmole 4MU/hour x g dry matter for the D-Gro A and Biovækst composts, respectively. To increase chitinase activity the two composts were amended with chitin. This addition induced a change in both the bacterial and fungal genetic diversity when compared to the non-amended compost samples. Likewise, both composts reacted to the addition of chitin with an increase in chitinase activity (p<0.05). Thus, a relationship between genetic and functional diversity was established for the composts in question. The N-mineralization in the household waste compost was apparently increased by the addition of chitin, while such an effect was not observed in the garden/park waste compost.