Photosynthesis microalgae

Macintyre, H. L., Sharkey, T. D., and Geider, R. J. (1997). Activation and deactivation of ribulose-1,5-bisphosphate carboxylase/oxygenase (rubisco) in three marine microalgae. Photosynthesis Res. 51, 93-106. 

Negoro, M., et al., Carbon Dioxide Fixation by Microalgae Photosynthesis Using Actual Flue Gas Discharged from a Boiler, 14th Symposium on Biotechnology for Fuels and Chemicals, Gatlinburg, TN (May 1992). 

As nonconservative gases, carbon dioxide and oxygen are closely coupled to the organic carbon pool through autotrophic (e.g., photosynthesis) and heterotrophic (e.g., respiration) processes. The dominant primary producers in estuaries and the coastal ocean are benthic and pelagic microalgae (phytoplankton). The average atomic C-to-N-to-P ratio... 

Hewson, 1., O Neil, J. M., Hed, C. A., Bratbak, G., and Dennison, W. C. (2001c). Effects of concentrated natural viral communities on photosynthesis and community composition of co-occuring benthic microalgae and phytoplankton. Aquat. Microb. Ecol. 25, 1—10. 

Aquatic microalgae are characterized by their efficient photosynthesis and their fast proliferation compared with terrestrial C3- and C -plants. Hence, microalgae can be considered as a candidate for biological catalyst in GO2 fixation. 

Since dissolved inorganic carbon, such as free CO2 and bicarbonate, acts as a sole carbon source in photoautotrophic growth of microalgae, the partial pressure of CO2 in the atmosphere or in the supplied gas mixture is an important factor for their growth. Studies on the mechanisms underlying the efficient photosynthesis of microalgae in air level CO concentration (L-COj, 0.036%) will be described. 

Some kinds of higher plants developed a clever system, so-called C, photosynthesis, to attain high productivity under L-COj condition. However, photosynthesis is much more efficient in microalgae than in plants [1],... 

The supply of extremely high concentrations of CO into the cultures of microalgae can cause acidification in both extra- and intracellular environment due to the formation of acidic substances in the course of COj hydration. Many enzymatic reactions in photosynthesis and metabolism may be inhibited under low intracellular pH. Therefore, the ability to maintain intracellular pH stable seems to be one of the important factors for the cells to grow rapidly at the exposure to H-COj. The P-NMR spectroscopy was applied for measuring pH values in different cellular compartments, which were confirmed with the DMO method. The drop in cytoplasmic pH was observed when S. baciUaris cells were exposed to 40% COj, while pH in C. littorale was stable up to 60% CO. This indicates that the growth inhibition by high CD was associated with cytoplasmic acidification [13]. 

We have studied CO2 fixation of the exhaust gas from thermal power stations by microalgal photosynthesis. In order to utilize the resulting large quantities of biomass for fuel, compost, feed and other useful chemical substances, we have screened microalgae which produce lipids or hydrocarbons. In this study, we report the isolation and characterization of a green alga tolerant of the concentration of 10%CO2 at30t . 

The effects of mono- and dinitrophenols as well as aminophenols (APs) on photosynthesis, respiration, and chlorophyll production of the microalga C. pyrenoidosa were analyzed [52], These compounds caused hormesis (dose-response phenomenon characterized by low dose stimulation and high dose inhibition, resulting in either a J-shaped or an inverted U-shaped dose response curve) on chlorophyll production at concentrations of NP, DNP, and AP ranging from 92 to 458 prnolcs L-1. The reader is directed to Chapter 3 of this book for a discussion of hormetic responses of terrestrial receptors to energetic materials. 

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