# Wheat aroma biomarkers induced by saline-alkali soil: based on HS-SPME-GC-MS and molecular docking

## TL;DR

This study identifies specific volatile compounds in wheat grown in saline-alkali soil that contribute to its distinct aroma.

## Contribution

The research identifies limonene, β-pinene, and (E,E)-3,5-octadien-2-one as potential biomarkers for wheat aroma induced by saline-alkali soil.

## Key findings

- 75 volatile compounds were identified in wheat samples using HS-SPME-GC-MS.
- Limonene and β-pinene showed significant increases in saline-alkali soil-grown wheat.
- Molecular docking confirmed high binding affinity of key compounds to olfactory receptors.

## Abstract

The precise volatile compounds accountable for the characteristic scent of the wheat aroma were presently unidentified. Given the prominent manifestation of “wheat aroma” in wheat cultivated in saline-alkali (SA) soil, five wheat varieties planted in saline-alkali soil and control soil (low saline-alkali soil) to create “rich-aroma” and “bland-aroma” samples, respectively.

The volatile profiles of these two groups of samples were analyzed using headspace solid-phase microextraction coupled with gas chromatographyed with gas chromathes-SPME-GC-MS), and differential characteristic volatile compounds between “rich-aroma” and “bland-aroma” samples were identified by combining paired t-tests, relative odor activity values (ROAVs), and molecular docking analysis.

A total of 75 volatile compounds were identified using HS-SPME-GC-MS. Paired t-test result revealed that a significant increase (p < 0.05) in the peak areas and relative contents of limonene (>109.74% increase), β-pinene (> 474.09% increase) contrasted with reduced butanoic acid (>38.71% reduction) and (E,E)-3,5-octadien-2-one (>16.05% reduction) in saline-alkali soil-cultivated wheats. Molecular docking demonstrated high binding energies (<-4.25 kcal/mol) of limonene, β-pinene, and (E,E)-3,5-octadien-2-one to olfactory receptors, corroborated by relative odor activity values (ROAVs. > 1).

Limonene, β-pinene and (E,E)-3,5-octadien-2-one are identified as possible saline-alkali soil-induced wheat aroma biomarkers, and offer theoretical insights for verificating wheat aroma. Identifying potential characteristic biomarkers in wheat under saline-alkali stress provides important theoretical insights for improving the flavor characteristics of wheat.