Research Progress on Enrichment of γ-Aminobutyric Acid in Plants under Environmental Stress

Gamma-aminobutyric acid (GABA) is a four-carbon non-protein constituent amino acid, has many physiological functions, such as easing nervous tension, falling the blood pressure, promoting sleep and other effects. It is reported that some plants are rich in GABA, suggesting their good prospect towards functional food development. In this review, two metabolic pathways of GABA synthesis were described, including GABA shunt and polyamide degradation. Furthermore, the impact of environmental stresses (i.e., cold, heat, salt and drought) on the content of GABA in different plants, such as brown rice, wheat, corn and soybean, and their potential application in food industry were also explored.