The modulation of light quality on carotenoid and tocochromanol biosynthesis in mung bean (Vigna radiata) sprouts

This study aimed to identify the regulatory mechanisms of white, blue, red lights on carotenoid and tocochro-manol biosynthesis in mung bean sprouts. Results showed that three lights stimulated the increase of the pre-dominated lutein (3.2-8.1 folds) and violaxanthin (2.1-6.1 folds) in sprouts as compared with dark control, as well as beta-carotene (20-36 folds), with the best yield observed under white light. Light signals also promoted alpha-and gamma-tocopherol accumulation (up to 1.8 folds) as compared with dark control. The CRTISO, LUT5 and DXS (1.24-6.34 folds) exhibited high expression levels under light quality conditions, resulting in an over-accumulation of carotenoids. The MPBQ-MT, TC and TMT were decisive genes in tocochromanol biosynthesis, and were expressed up to 4.19 folds as compared with control. Overall, the results could provide novel insights into light-mediated regulation and fortification of carotenoids and tocopherols, as well as guide future agricul-tural cultivation of mung bean sprouts.