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Updated: Oct 19, 2025

Single-throughput Complementary High-resolution Analytical Techniques for Characterizing Complex Natural Organic Matter Mixtures

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Published on: January 7, 2019

Nitrate shifted microenvironment: Driven aromatic-ring cleavage microbes and aromatic compounds precursor

Mingzi Shi¹, Chengguo Liu², Yumeng Wang¹

¹College of Life Science, Northeast Agricultural University, Harbin 150030, PR China.

Bioresource Technology

|September 18, 2021

Summary

Nitrate addition to sludge composting enriches microbes that break down aromatic compounds. These microbes reduce aromatic humic substances, suggesting controlled nitrate and microbial levels can improve composting.

Keywords:

Aromatic cleavage pathway Aromatic compounds humic substances Aromatic-ring cleavage functional microbes Nitrate Sludge composting

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Published on: October 15, 2015

Area of Science:

Environmental Microbiology
Soil Science
Biogeochemistry

Background:

Nitrate can negatively impact aromatic compounds in humic substances during sludge composting.
Understanding the microbial pathways involved is crucial for optimizing composting processes.

Purpose of the Study:

To elucidate the aromatic cleavage pathways and microbial communities responsible for nitrate's adverse effects on humic substances during sludge composting.
To identify key microbial players and their interactions in the degradation of aromatic compounds.

Main Methods:

Analysis of microbial community structure and function after nitrate addition.
Linear regression and network analysis to determine microbial correlations and interactions.
Structural equation modeling to understand the influence of the composting microenvironment on microbial activity.

Main Results:

Nitrate addition significantly enriched functional microbes involved in the cleavage of aromatic compound precursors (catechol, tyrosine, tryptophan, phenylalanine).
Aromatic-ring cleavage functional microbes showed a significant negative correlation with aromatic humic substances.
Microbial communities predominantly cooperated with aromatic-ring cleavage microbes, driven by the composting microenvironment, leading to biodegradation.

Conclusions:

Nitrate's adverse effect on humic substances is mediated by specific microbial communities that degrade aromatic compounds.
Controlling nitrate concentration and promoting specific aromatic-ring cleavage microbes are recommended for effective sludge composting.
This study provides a novel perspective on mitigating negative impacts by understanding microbial degradation pathways.