Fungal degradation of complex organic carbon supports denitrification in saturated woodchip bioreactors

Hao Wang; Gary W Feyereisen; Jiwei Zhang; Satoshi Ishii

doi:10.1016/j.biortech.2024.131826

Fungal degradation of complex organic carbon supports denitrification in saturated woodchip bioreactors

Bioresour Technol. 2024 Nov 20:417:131826. doi: 10.1016/j.biortech.2024.131826. Online ahead of print.

Authors

Hao Wang¹, Gary W Feyereisen², Jiwei Zhang³, Satoshi Ishii⁴

Affiliations

¹ Department of Soil, Water, and Climate, University of Minnesota, 1991 Upper Buford Circle, 439 Borlaug Hall, St. Paul, MN 55108, USA. Electronic address: wang4637@umn.edu.
² USDA-ARS Soil and Water Management Research Unit, 1991 Upper Buford Circle, 439 Borlaug Hall, St. Paul, MN 55108, USA. Electronic address: gary.feyereisen@usda.gov.
³ Department of Bioproducts and Biosystems Engineering, University of Minnesota, 2004 Folwell Ave, Kaufert Laboratory, St. Paul, MN 55108, USA. Electronic address: zhan3437@umn.edu.
⁴ Department of Soil, Water, and Climate, University of Minnesota, 1991 Upper Buford Circle, 439 Borlaug Hall, St. Paul, MN 55108, USA; BioTechnology Institute, University of Minnesota, 140 Gortner Lab, 1479 Gortner Ave., St. Paul, MN 55108, USA. Electronic address: ishi0040@umn.edu.

PMID: 39577781
DOI: 10.1016/j.biortech.2024.131826

Abstract

Woodchip bioreactor (WBR) is a promising technology for the removal of nitrate from agricultural drainage, although the performance of WBRs is dependent on the decomposition of lignocellulosic biomass and the carbon availability for microbial denitrification. Fungal species are more efficient than bacterial counterparts in driving wood decomposition; however, little is known about the fungal community structure and functions in saturated WBRs. In this study, we investigated the dynamics of the mycobiome in field-scale, constantly saturated WBRs located in Willmar, Minnesota, USA. Fungal community analysis suggested that wood-rotting fungi were abundant in WBRs, especially near their inlet locations where microbial denitrification was most active. Complex network structures of fungal hyphae associated with a decayed cavity on the woodchip surface was further evidenced by confocal and scanning electron microscopy. These results suggest that fungi play a major role in wood degradation in WBRs, thereby promoting denitrification activity.