# Enhancing Brassica microgreen production: Exploring metabolomic variations across growing conditions using targeted and non-targeted analysis

## TL;DR

This study explores how different light and temperature conditions affect the chemical makeup and growth of Brassica microgreens.

## Contribution

The paper introduces a combined targeted and non-targeted metabolomic approach to assess the impact of growing conditions on Brassica microgreens.

## Key findings

- A prolonged photoperiod increased chlorophyll content by 32% and microgreen height by 20%.
- Phenolic compounds like gallic and ferulic acid were significantly influenced by growing conditions.
- Extended photoperiods elevated levels of myo-inositol, glucose, and specific indolylmethyl compounds.

## Abstract

The present study investigated the impact of different photoperiods and temperatures as growing conditions (GCs) on the metabolomic profile of Brassica microgreens. The research delves into the intricate chlorophyll content, macroelement composition and metabolomic profiles of Brassica species cultivated under varied GC by utilizing targeted and non-targeted compound analysis. Under the G3 (a prolonged photoperiod of 22 h with temperatures of 26 °C/20 °C:: light/dark), Brassica microgreens demonstrated a rise in chlorophyll content by about 32 %, while microgreen height increased by approximately 20 %. The macroelement composition also varied significantly with GC, notably potassium content increased from 42.93 to 66.18 mg/g under G3. The phenolic composition analysis revealed a prominent presence of gallic and ferulic acid in the microgreens, significantly influenced by the GCs. Additionally, sugar profile indicated elevated levels of glucose and sucrose in response to G3. The UHPLC-QToF-IMS metabolomic profile highlighted the variation in expression levels of different classes of compounds, specifically (2R)-2-Hydroxy-3-butenyl, and 3-Indolylmethyl, which were upregulated under the G3.

•Total chlorophyll content increased in response to longer photoperiod.•The concentration of individual phenolic compounds varied with growing conditions.•Extended photoperiods elevated myo-inositol and glucose levels.•The expression level of 4-Methoxy-3-indolylmethyl and 3-Indolymethyl increased under longer photoperiod.

Total chlorophyll content increased in response to longer photoperiod.

The concentration of individual phenolic compounds varied with growing conditions.

Extended photoperiods elevated myo-inositol and glucose levels.

The expression level of 4-Methoxy-3-indolylmethyl and 3-Indolymethyl increased under longer photoperiod.