Antioxidant Capacity of Flavonoid in Soybean Seedlings under the Joint Actions of Rare Earth Element La(III) and Ultraviolet-B Stress

Abstract

The dynamic state of antioxidant capacity of flavonoid was investigated for a further demonstration of alleviating the damage of the ultraviolet (UV)-B radiation in the La-treated soybean seedlings under UV-B stress. Using hydroponics culture, the effects of lanthanum on the contents of flavonoid and its ability of antioxidant under elevated ultraviolet-B radiation (280-320 nm) was studied. The results showed flavonoid content in soybean seedlings with UV-B treatment during the stress and convalescent period was increased initially and then decreased, compared with control. Membrane permeability and MDA contents increase at first (first to fifth day) and then decrease (6th-11th day). A similar change of flavonoid content and clearance of flavonoid scavenging O2- and *OH in soybean seedlings occurred. Flavonoid content and ability of flavonoid scavenging O2- and *OH in soybean seedlings with La(III) + UV-B treatment were higher than those of UV-B treatment. Meanwhile, membrane permeability and MDA contents in soybean seedlings were lower than those of UV-B treatment. Compared with control, phenylalanine content in soybean seedlings with UV-B treatment is depressed, phenylalanine content in soybean seedlings with La(III) treatment was enhanced. However, phenylalanine content in La(III) + UV-B treatment is not decreased but slightly increased, compared with UV-B treatment. It suggested that the regulative effect of La(III) of the optimum concentration on flavonoid improved the metabolism of ROS, diminished the concentration of MDA and maintained normal plasma membrane permeability, and that its protective effect against low UV-B radiation is superior to that of high UV-B radiation. The defensive effect of La(III) on soybean seedlings under UV-B stress is carried out on the layer of defense system.

Responses of Wheat Seedlings to Exogenous Selenium Supply Under Cold Stress

“…Flavonoids, anthocyanins, and phenolic compounds have been proven to have the ability to scavenge free radicals and inhibit membrane lipid peroxidation of seedlings [26][27][28]. In our study, Se treatments significantly increased anthocyanins, flavonoids, and phenolic compounds content (Fig.…”

Antioxidant Responses of Wheat Seedlings to Exogenous Selenium Supply Under Enhanced Ultraviolet-B

“…It is generally accepted that the mechanism of UV-B toxicity mainly involves oxidative damage [4,5]. When plants are exposed to UV-B radiation stress, some protective mechanism can be formed in plants.…”

The effect of anthocyanin-rich bilberry extract on the antioxidant system in roots of barley (Hordeum vulgare L.) cultivars under ionizing radiation

“…Increases or decreases in TP content in irradiated plants have been reported to vary, depending on the level of radiation, plant species, and the vegetative part of the plant . Similar to the effect of phenolics, flavonoids minimize the oxidative damage induced by ionizing irradiation stress in plants (Peng and Zhou 2009;Moghaddam et al 2011). However, TF content increased in the IR group in the roots of radiosensitive cvs, while, in radioresistant cvs, the content was unaffected by the same treatment.…”