@article{Shotaro Tadama_Hideaki Shiraishi_2016, title={GROWTH OF THE EDIBLE MICROALGA ARTHROSPIRA PLATENSIS IN RELATION TO BORON SUPPLY}, volume={12}, url={https://geomatejournal.com/geomate/article/view/1238}, abstractNote={<p>Arthrospira (Spirulina) platensis is an edible cyanobacterium that has been consumed <br>worldwide as a nutrient source under the name spirulina. When preparing synthetic media for this microalga, <br>boron is usually added to them. However, whereas boron is necessary for the N2-fixation-dependent growth <br>of heterocystous cyanobacteria, boron requirement by A. platensis, which is non-heterocystous, has not yet <br>been carefully examined. To examine the effect of boron on A. platensis, we prepared a boron-depleted <br>medium in which borate concentration was below a detection limit (0.2 µM), as determined by the <br>spectrophotometric quantitation with H-resorcinol. Using this boron-depleted medium, A. platensis NIES-39 <br>was analyzed for changes in growth, dry biomass weight and the protein, chlorophyll a and C-phycocyanin <br>contents. Experimental results showed that removal of boron from the growth medium had no detectable <br>effect on them. A control experiment with a heterocystous cyanobacterium Anabaena sp. UTEX 2576 <br>showed that the growth of this cyanobacterium was suppressed in a boron-depleted medium. These <br>experiments demonstrated that boron was not required for the growth of A. platensis. Our results indicate that <br>boron supply is not necessary for the propagation of A. platensis even in the regions where boron deficiency <br>in the soil deteriorates the growth of common crops. Use of boron-free media would also be helpful to <br>improve the reproducibility of sensitive physiological experiments such as metabolome analysis, because <br>precipitation of the insoluble salt manganese borate, which may reduce the concentration of Mn2+ in the <br>medium, does not occur in boron-free media.</p>}, number={30}, journal={GEOMATE Journal}, author={Shotaro Tadama and Hideaki Shiraishi}, year={2016}, month={Dec.}, pages={90–95} }