Influence of pre-harvest red light irradiation on main phytochemicals and antioxidant activity of Chinese kale sprouts

•Pre-harvest red light irradiation postponed the degradation of glucosinolates.•Pre-harvest red light irradiation significantly increased the vitamin C content.•Pre-harvest red light irradiation enhanced the accumulation of total phenolics.•Antioxidant activity was elevated by pre-harvest red light treatment.

The effects of pre-harvest red light irradiation on main healthy phytochemicals as well as antioxidant activity of Chinese kale sprouts during postharvest storage were investigated. 6-day-old sprouts were treated by red light for 24 h before harvest and sampled for further analysis of nutritional quality on the first, second and third day after harvest. The results indicated that red light exposure notably postponed the degradation of aliphatic, indole, and total glucosinolates during postharvest storage. The vitamin C level was remarkably higher in red light treated sprouts on the first and second day after harvest when compared with the control. In addition, red light treatment also enhanced the accumulation of total phenolics and maintained higher level of antioxidant activity than the control. All above results suggested that pre-harvest red light treatment might provide a new strategy to maintain the nutritive value of Chinese kale sprouts during postharvest storage.