Related Experiment Video
Updated: Mar 11, 2026
Author Spotlight: Optimizing Growth Factors for Production of Biotechnologically Relevant Secondary Metabolites
Published on: October 25, 2024
Evaluation of radical scavenging system in two microalgae in response to interactive stresses of UV-B radiation and
Sarah A Al-Rashed1, Mohamed M Ibrahim2, Gehan A El-Gaaly1
1King Saud University, Science College, Botany and Microbiology Department, P.O. Box 2455, Riyadh 11451, Saudi Arabia.
Abstract:
The effects of UV-B radiation and/or deprivation of nitrogen stresses on growth rate, some antioxidant compounds, and activities of some antioxidant enzymes, superoxide dismutase (SOD; EC1.15.1.1), ascorbate peroxidase (APx; EC1.11.1.11), guaiacol peroxidase (GUPx; EC1.11.1.7) and glutathione reductase (GR, EC 1.6.4.2), as well as the levels of total glutathione pool, UV-B absorbing pigments, malondialdehyde (MDA) and H2O2 concentrations were studied in Spirulina platensis and Dunaliella salina. Less damage was observed in response to the combined UV-B and nitrogen deprivation as shown by growth rate and photosynthetic pigments especially in Dunaliella salina. A significant increase in flavonoids and phenolics under dual stress was observed. Conversely, a great reduction in malondialdehyde (MDA) and H2O2 concentrations were recorded under the combined stress compared to the effect of each stress. Furthermore, a significant increase in GSH/GSSG ratio toward the control was recorded in response to combined stresses, whereas a significant reduction in this ratio was observed in both microalgae in response to each stress. Increased activities of antioxidant enzymes were recorded under UV-B and nitrogen deprivation stresses.
