Inhibition of the water splitting system by sodium chloride stress in the green alga Chlorella vulgari

Abstract

The effect of sodium chloride on the photosynthetic electron transport chain was investigated in the freshwater green alga Chlorella vulgaris. It was found that the rate of oxygen evolution under steady state and flash light conditions diminished by increasing salt concentrations. Salt treatment of cells also decreased the fluorescence and delayed luminescence yields. However, the fluorescence yield was almost completely restored by the addition of an artificial electron donor to the NaCl-treated cells. The oscillation pattern of the thermoluminescence B band as a function of flash number indicated that the S2<FONT FACE=Symbol>®</FONT>S3 transition of the water splitting system is inhibited by NaCl treatment.

The Detection of Calcium and Sodium using Green Algae Spirogyra

“…The iontic stress created by Ca might trigger the production of ROS, which would affect the level of the pigments (Sharma et al, 2012). The introduction of Na altered the salinity of the medium, which creates stress to the algae (EL- Sheekh, 2004). The additional Na may lead to the changes of pottasium (K) and Na balance and further According to Xiong et al (2002), plant cells could tolerant the ROS generated by ionic stress through the production of antioxidants (Sharma et al, 2012), thus might cause the "bounce-back" effects as shown in the 24 hours and 48 hours response curves.…”

Effects of Bicarbonate Limitation and Salinity Stress on Growth and Photosynthesis in the Green Alga Picochlorum Oklahomensis

“…Even though the pigments may not be affected, electron flow is interrupted and this may finally affect the dark reactions. El-Sheekh (2004), has reported that elec-tron transfer from Q A to Q B was decreased by salinity stress in the green alga Chlorella vulgaris, a relative of Picochlorum (Henley et al, 2004). Salt stress can inhibit protein synthesis such as the D1 protein which will in turn affect the rates at which damaged D1 proteins are replaced and subsequently affect photosynthesis (Allakhverdiev et al, 2002;Mohanty et al, 2007).…”

“…Picochlorum sp. is classified as belonging to the Domain Eukarya, Kingdom Protista, Division Chlorophyta and Class Trebouxiophyceae (Graham and Wilcox, 2000;Henley et al, 2002;2004). (Henley et al, 2002).…”