Variation of functional compounds in leafy Chinese cabbage grown under different light conditions in a plant factory

Abstract

A recently developed Chinese cabbage cultivar, Shinhong Ssam, was cultured under different light conditions at a plant factory to evaluate effects of light on the production of functional compounds. The effects of the following combinations of red (R), blue (B), and white (W) LED light were compared to that of fluorescent light: R+B, R+W, and R+B+W. Under R+B light, the Chinese cabbage failed to grow well. In contrast, under R+W, R+B+W, and fluorescent light conditions, cabbages had similar growth rates. Cyanidin, the only anthocyanidin detected, accumulated in cabbages under LED conditions to levels more than 2-fold of that in cabbages grown under fluorescent light. Phenolic acid and flavonol levels varied subtly, whereas caffeic acid was found to be between 70- and 160-fold greater in LED-illuminated cabbages than in those exposed to fluorescent light. The amounts of free amino acids and sugars that affect the taste of vegetables were greater in the cabbages exposed to LED light than in those grown under fluorescent light conditions. In conclusion, R+W LED light produced Shinhong Ssam with greater nutritional value than those grown under R+B+W LED and fluorescent lights.