Effects of ratio of manganese peroxidase to lignin peroxidase on transfer of ligninolytic enzymes in different composting substrates

The transfer of ligninolytic enzymes in composting substrates (soil, vegetable leaf, rice straw and chaff) was investigated using a series of column elution experiments. Environmental scanning electron microscope (ESEM) and Fourier transform infra-red spectroscopy (FTIR) were used to analyze the mechanism of ligninolytic enzymes adsorption onto those substrates. The significant differences were found between substrates with adsorption of enzymes and those without enzymes by FTIR. Hydrophobic groups (methylene and alkane groups) and active groups (CH2CO or CH2NH) contents decreased in the substrates with adsorption of enzymes. The transfer abilities of total protein in the four composting substrates (soil, vegetable leaf, rice straw and chaff) were weakened as the ratio of manganese peroxidase (MnP) to lignin peroxidase (LiP) increased from 4 to 6, and were enhanced when the MnP/LiP ratio increased to 8. The transfer abilities of LiP in the four composting substrates were enhanced continually with the increasing MnP/LiP ratio. The transfer of MnP was similar to that of total protein with the change of MnP/LiP ratio. These results indicated that the change of MnP/LiP ratio could affect the transfer of ligninolytic enzymes in different composting substrates.

► Laboratory simulation tests of the transfer of ligninolytic enzymes in composting substrates (soil, vegetable leaf, rice straw and chaff) were studied.
► The physico-chemical properties of composting substrates had effect on the transfer of ligninolytic enzymes in composting substrates.
► The results of transfer experiment were consistent with the FTIR spectrometry.
► The transfer of ligninolytic enzymes in different substrates changed as the MnP/LiP ratio changed.