Effect of excessive CO2 on physiological functions in coastal diatom

Abstract

Rising dissolution of anthropogenic CO2 in seawater may directly/indirectly cause ocean acidification and desalination. However, little is known about coastal physiological functions sensitivity to these processes. Here we show some links between ocean acidification/desalination and physiological functions in Thalassiosira weissflogii. Cell density (CD), protein, chlorophyll a (Chl a), malonaldehyde (MDA), superoxide dismutase (SOD), and carbonic anhydrase (CAs) were determined for the assessment of algal biomass, nutritional value, photosynthesis and respiration, lipid peroxidation, antioxidant capacity, and carbon sequestration ability. The influence of pH on the algal Chl a and MDA were extremely significant (P < 0.01). Salinity (S) on cell density and acidity (pH) on protein was significant (0.01 < P < 0.05). Additionally, a significant negative-correlation was observed between cell density and CAs. CAs and SOD had negatively correlations with CD, Chl a, protein, and MDA under pH or S influence, but positive correlation between themselves. Coastal physiological functions were affected by increasing order was acidification < acidification + desalination < desalination for Chl a and protein, desalination < acidification + desalination < acidification for SOD and CAs. Thus, the ongoing excessive CO2-driven ocean acidification and desalination should be of high attention when assessing the risks of climate change on coastal phytoplankton.

Antioxidative Properties of Baltic Sea Keystone Macroalgae (Fucus vesiculosus, Phaeophyceae) under Ocean Warming and Acidification in a Seasonally Varying Environment

“…To our knowledge, there are only very few studies dealing with the effect of CO 2 -induced acidification of seawater on the antioxidative potential of micro- and macroalgae. Acidification increased the MDA content of a diatom ( Thalassiosira weissflogii ) and a brown seaweed species ( Sargassum vulgare) , indicating that membrane lipid peroxidation was enhanced [ 98 , 99 ]. Additionally, the induction of SOD in S. vulgare under acidified conditions points to its major role in preventing ·O 2 − overproduction.…”

Stress-induced secondary carotenogenesis in Coelastrella rubescens (Scenedesmaceae, Chlorophyta), a producer of value-added keto-carotenoids

“…A similar effect might take place in the СО 2 over-supplemented cultures. Thus, in Thalassiosira weissflogii cells an abrupt decline in рН triggered a dramatic increase in malonic dialdehyde, the product of lipid peroxidation and a marker of oxidative stress (Liu et al 2016). Still we did not observe the mass death of young cells such as took place in H. pluvialis cul-tent, respectively).…”

Renal Denervation Attenuates Multi-Organ Fibrosis and Improves Vascular Remodeling in Rats with Transverse Aortic Constriction Induced Cardiomyopathy

“…Superoxide dismutase (SOD) plays a major role in antioxidant defense by catalyzing the dismutation process of superoxide anion into oxygen and hydrogen peroxide. Malonaldehyde (MDA), a product of lipid peroxidation, is regarded as an indicator of free radical activity and tissue damage [41]. In the failing heart, the expression of Ang II, TGF-β1 and MDA increases, while the expression of SOD decreases [17,42].…”