Temperature and Light Regimes Shape Seasonal Variation in Glucosinolate Hydrolysis in Red Cabbage

Area of Science:

• Plant biochemistry
• Agricultural science
• Nutritional science

Background:

• Glucosinolate hydrolysis in Brassica oleracea produces health-promoting isothiocyanates (ITCs) but can also yield less bioactive nitriles and epithionitriles.
• Understanding factors influencing this metabolic pathway is crucial for enhancing crop nutritional value.

Purpose of the Study:

• To investigate the impact of temperature, light intensity, and photoperiod on glucosinolate metabolism in red cabbage.
• To determine how different developmental stages (sprouts and mature plants) affect these responses.

Main Methods:

• Controlled simulation of summer and autumn cultivation conditions.
• Analysis of glucosinolate hydrolysis products (ITCs, nitriles, epithionitriles).
• Proteome and transcript analyses to examine protein and gene expression (BoESP1-3, BoESM1).

Main Results:

• High light and warm temperatures (16-h photoperiod, 23.4 mol m⁻² d⁻¹, 25 °C) favored ITC formation.
• Cold, short-day conditions (8h photoperiod, 7.0 mol m⁻² d⁻¹, max 15 °C) enhanced nitriles and epithionitriles.
• Light was identified as the primary factor regulating specifier proteins, influencing hydrolysis outcomes.

Conclusions:

• Environmental conditions, particularly light, significantly modulate glucosinolate hydrolysis pathways in red cabbage.
• Targeted cultivation strategies can be employed to improve the nutritional quality of Brassica crops by optimizing environmental factors.
• Differential expression of specifier and modifier proteins is linked to environmental shifts and metabolic responses.