UV-A and FR irradiation improves growth and nutritional properties of lettuce grown in an artificial light plant factory

• Published in: Food chemistry Vol. 345; p. 128727
• Main Authors: He, Rui, Zhang, Yiting, Song, Shiwei, Su, Wei, Hao, Yanwei, Liu, Houcheng
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 30.05.2021
• Subjects: 2,2-diphenyl-1-picrylhydrazyl; anthocyanins; antioxidant activity; Antioxidants - analysis; Antioxidants lettuce; ascorbic acid; Ascorbic Acid - analysis; Biomass; chlorophyll; Chlorophyll - analysis; cultivars; Environment, Controlled; Far-red light; Flavonoids - analysis; food chemistry; irradiation; Lactuca - chemistry; Lactuca - growth & development; Lactuca - radiation effects; leaf area; leaf development; lettuce; Light; nitrates; Nitrates - analysis; Nutrients - analysis; Plant Leaves - chemistry; Plant Leaves - growth & development; Plant Leaves - radiation effects; polyphenols; Primary metabolites; Sugars - analysis; Ultraviolet A light; ultraviolet radiation; Far-red light; Primary metabolites; Ultraviolet A light; Antioxidants lettuce
• ISSN: 0308-8146; 1873-7072; 1873-7072
• DOI: 10.1016/j.foodchem.2020.128727

•Ultraviolet A (UV-A) supplementation reduced the leaf area and biomass in lettuce.•UV-A supplementation improved the chlorophyll, soluble protein, soluble sugar, vitamin C contents.•UV-A supplementation improved the flavonoid, polyphenol, and anthocyanin contents and DPPH free radical-scavenging rate.•Far-red (FR) light yielded larger leaf area, but no significant improvement in biomass.•Combined UV-A and FR light improved leaf area and biomass, but reduced phytochemical contents. This study investigated the individual and combined effects of ultraviolet A (UV-A) and far-red (FR) light irradiation on the biomass, phytochemical accumulation, and antioxidant capacity of two lettuce cultivars in an artificial light plant factory. UV-A supplementation yielded a smaller leaf area and reduced biomass and nitrate content. In contrast, it improved the chlorophyll, soluble protein, soluble sugar, vitamin C, flavonoid, polyphenol, and anthocyanin contents and the 2,2-diphenyl-1-picrylhydrazyl radical-scavenging rate. FR irradiation resulted in a larger leaf area, whereas the lettuce biomass remained unchanged. Irradiation with both UV-A and FR light exhibited the most remarkable effect on leaf expansion and biomass, but reduced the phytochemical contents. A significant interaction between the cultivar and supplemented light was observed for most plant parameters.