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Malabar spinach ( Basella alba ), amaranth ( Amaranthus tricolor ), and sweet potato ( Ipomoea batatas ) are leafy vegetables found in Southwest China. The variation of chlorophyll, carotenoids, ascorbic acid, total flavonoids, phenolic compounds, and antioxidant capacity was studied in the leaves and stems of the three vegetables. The content of main health-promoting compounds and the antioxidant capacity in the leaves were higher than that in the stems, indicating that the leaves of the three vegetables possess greater nutritional value. The trend of total flavonoids in all three vegetables was similar to the trend of antioxidant capacity, suggesting that the total flavonoids may be the major antioxidants wihin these vegetables. Eight individual phenolic compounds were detected in three different vegetables. The most abundant levels of individual phenolic compounds in the leaves and stems of malabar spinach, amaranth, and sweet potato were 6'- O -feruloyl-d-sucrose (9.04 and 2.03 mg g -1 DW), hydroxyferulic acid (10.14 and 0.73 mg g -1 DW), and isorhamnetin-7- O -glucoside (34.93 and 6.76 mg g -1 DW), respectively. Sweet potato exhibited a higher total and individual phenolic compound content compared to malabar spinach and amaranth. Overall, the results demonstrate that the three leafy vegetables possess high nutritional value, and could be used not only for consumption but also in various other fields, including medicine and chemistry.

The ability of white, red, and blue irradiation to maintain sensory quality, health-promoting compounds, and antioxidant capacity, and regulate glucosinolate metabolism-related gene expression in post-harvest baby mustard was studied. Irradiation with 80 µmol m -2 s -1 extended the shelf life of post-harvest baby mustard. Irradiation delayed the increase in weight loss and the decrease in sensory parameter scores and the levels of ascorbic acid, total phenolics, glucosinolate, and antioxidant capacity during storage of baby mustard. Irradiation induced the expression of glucosinolate biosynthesis genes and inhibited glucosinolate degradation gene expression. The glucosinolate content and glucosinolate metabolism-related gene expression in post-harvest baby mustard were higher under white and red light irradiation compared with blue light irradiation. These findings indicate that irradiation (80 µmol m -2 s -1 ), especially of white and red light, is an effective technique for maintaining the sensory and nutritional qualities in post-harvest baby mustard stored at 20°C. PRACTICAL APPLICATION: This study was to evaluate the effect of white, red, and blue irradiation on the sensory quality, health-promoting compounds, antioxidant capacity, and glucosinolate metabolism-related gene expression of baby mustard during post-harvest storage, providing an effective and sustainable post-harvest method to extend shelf life and maintain the post-harvest quality of baby mustard under ambient temperature storage. Irradiation (80 µmol m -2 s -1 ), especially of white and red light, is an effective technique for maintaining the sensory and nutritional qualities in post-harvest baby mustard stored at 20°C., (© 2021 Institute of Food Technologists®.)

The effect of light exposure on sensory quality, health-promoting phytochemical contents, and antioxidant capacity in the lateral buds of baby mustard plants was investigated at ambient storage temperature (20 °C). The results showed that light exposure (36 μmol m -2 s -1 ) during post-harvest storage significantly prolonged shelf life (more than 1.75-fold), delayed the weight loss and the decrease of firmness. Light treatments also enhanced chlorophyll and carotenoid contents, and retarded declines in contents of soluble sugars, ascorbic acid, flavonoids and glucosinolates, as well as antioxidant capacity. The quality of baby mustard plants receiving 24 h daily light treatment was superior to those in plants receiving 12 h treatment and constant darkness at 20 °C. These findings indicate that light exposure, especially 24 h treatment, is an effective method of prolonging shelf life and maintaining sensory and nutritional qualities in baby mustard plants stored at ambient temperature., (Copyright © 2020 Elsevier Ltd. All rights reserved.)