Graduate School of Horticulture, Chiba University, Matsudo, Chiba, 271-8510, Japan; Department of Biotechnology, Faculty of Science, Mahidol University, Bangkok, 10400, Thailand.
National Center for Genetic Engineering and Biotechnology, National Science and Technology Development Agency, Thailand Science Park, Pathum Thani, 12120, Thailand.
Plant Physiol Biochem. 2022 Jul 1;182:202-215. doi: 10.1016/j.plaphy.2022.04.003. Epub 2022 Apr 25.
Baby-leaf vegetables are a trade name for leafy vegetables sold as leaves with petioles at the seedling stage. Amaranth (Amaranthus tricolor L.) is a nutritious baby-leaf vegetable containing many bioactive compounds. The effects of short-term ultraviolet B (UV-B) treatments on the growth and quality of baby leaf amaranth were studied, including the conditions of a 24-h recovery period after irradiation, and different irradiation intensities (3.0-9.0 W m), irradiation periods (4-16 h), and cumulative energies (130-170 kJ m). A recovery period experiment was conducted to observe the changes in the growth and quality of leaves at 0 and 24 h after UV-B irradiation. The results showed that the concentrations of phenolic compounds, flavonoids, anthocyanin, and ascorbic acid in the leaves, as well as the leaf antioxidant capacity increased 24 h after UV-B irradiation. Increases in target compound concentrations and antioxidant capacity without negative growth and appearance effects were observed in leaves irradiated with UV-B at 3, 6, and 9 W m for irradiation periods of 12 and 16, 8 and 12, and 4 h, respectively. The highest bioactive compound concentration was found in leaves irradiated with UV-B at 6 W m for 7 h (cumulative energy: 150 kJ m). It was concluded that UV-B irradiation at 6 W m with a cumulative energy of 150 kJ m and a 24 h post-irradiation recovery period could be an appropriate treatment to increase bioactive compounds in baby leaf amaranth without causing appearance abnormalities.
芽苗菜是以带叶柄的幼苗形式出售的叶菜类蔬菜的商品名。苋菜（Amaranthus tricolor L.）是一种营养丰富的芽苗菜，含有许多生物活性化合物。本研究探讨了短期紫外线 B（UV-B）处理对苋菜芽苗菜生长和品质的影响，包括照射后 24 小时恢复期的条件，以及不同的照射强度（3.0-9.0 W m）、照射时间（4-16 h）和累积能量（130-170 kJ m）。进行了恢复期实验，以观察 UV-B 照射后 0 和 24 小时叶片生长和品质的变化。结果表明，UV-B 照射后 24 小时，叶片中酚类化合物、类黄酮、花青素和抗坏血酸的浓度以及叶片抗氧化能力增加。在 3、6 和 9 W m 照射强度下，照射 12 和 16、8 和 12、4 h 时，叶片中目标化合物浓度和抗氧化能力增加，而生长和外观不受影响。在 6 W m 照射强度下，照射 7 小时（累积能量：150 kJ m）时，生物活性化合物浓度最高。结论认为，在 6 W m 累积能量为 150 kJ m 和照射后 24 小时恢复期的 UV-B 照射可能是一种合适的处理方法，可以在不引起外观异常的情况下增加苋菜芽苗菜中的生物活性化合物。
