# Evaluating the Chemical Reactivity of Wildfire-Derived Dissolved Organic Molecules: Glutathione Binding through Kendrick Mass Defect Analysis

## TL;DR

This study examines how wildfire-derived organic molecules react with glutathione, a key antioxidant, using advanced mass spectrometry techniques.

## Contribution

The paper introduces Kendrick Mass Defect analysis to identify glutathione bonding in wildfire-derived organic matter.

## Key findings

- Charred biomass samples showed a 10-fold increase in nitrogen- and sulfur-containing molecular formulas after reacting with glutathione.
- Approximately 25% of new molecular formulas were attributed to glutathione bonding via addition or condensation/elimination reactions.
- KMD analysis reveals a reactive fraction of wildfire-produced compounds relevant for toxicological studies.

## Abstract

The emerging risks to organisms of pyrogenic-derived
dissolved
organic matter (PyDOM) from forest fires are of concern due to its
toxic and mutagenic potential (e.g., pro-oxidative responses in fauna
through the depletion of glutathione, a nitrogen- and sulfur-containing
tripeptide found in cells). This study simulates this phenomenon in
a laboratory setting by identifying bonding between reduced l-glutathione and organic molecules in leachates from environmentally
weathered biomass samples (charred and uncharred) using Kendrick Mass
Defect (KMD) analysis from formula lists obtained from negative-mode
electrospray ionization-Fourier transform-ion cyclotron resonance-mass
spectrometry ((−)­ESI-FT-ICR-MS). These formula lists reveal
a 10-fold increase in nitrogen- and sulfur-containing molecular formulas
in the charred biomass samples compared with the unreacted charred
biomass when subjected to reaction with glutathione. KMD analysis
attributed the bonding of glutathione to the biomass leachates accounting
for approximately 25% of the new nitrogen- and sulfur-containing molecular
formulas as either addition-type or condensation/elimination-type
reactions. KMD sheds light on a different fraction of chemically reactive
wildfire-produced organic compounds that may be of interest for subsequent
toxicological studies.