The effect of 24-epibrassinolide on the green alga Acutodesmus obliquus (Chlorophyceae).

Brassinosteroids play an important role in the plant growth and development as well as in the adaptation of plants to environmental stresses. Studies have shown the effect of 24-epibrassinolide (EBL) in the range of concentrations 0.0001-10 μM on the green unicellular alga Acutodesmus obliquus (Chlorophyceae) during 7 days of cultivation. EBL is an effective stimulator of algal growth as it causes an increase in the number of cells and the contents of selected metabolites such as proteins, monosaccharides, and photosynthetic pigments (chlorophylls, carotenes, and xanthophylls). Furthermore, EBL inhibits the formation of reactive oxygen species such as hydrogen peroxide and oxidative damage as evidenced by a decrease of the lipid peroxidation. The positive effect of EBL resulting from the cellular oxidative state can be alleviated by antioxidants such as ascorbate peroxidase, catalase, superoxide dismutase, and ascorbate.