Cryopreservation of the edible alkalophilic cyanobacterium <i>Arthrospira platensis</i>

2016-05-31T10:17:28Z (GMT) by Hideaki Shiraishi
<p>Efficient cryopreservation conditions for the edible alkalophilic cyanobacterium <i>Arthrospira</i> (<i>Spirulina</i>) <i>platensis</i> were investigated using a model strain <i>A. platensis</i> NIES-39. As a result, it was found that more than 60% of cells were viable upon thawing, when they had been frozen at a cooling rate of approximately −1 °C min<sup>−1</sup> in the presence of 10% (v/v) dimethyl sulfoxide. Further examination with other <i>Arthrospira</i> strains showed that many of them had strain-dependent optimal conditions for cryopreservation. For example, the best freezing conditions for <i>A. platensis</i> SAG 21.99 were snap-freezing in liquid nitrogen in the presence of 5% (v/v) dimethyl sulfoxide, while they were slow cooling at approximately −1 °C min<sup>−1</sup> in the presence of 10% (v/v) methanol for <i>A. platensis</i> NIES-46, NIES-2308 and UTEX 1926. The variety of successful cryopreservation conditions presented in this study is useful when attempting to cryopreserve various <i>Arthrospira</i> strains.</p> <p>The conditions for efficient cryopreservation of <i>Arthrospira platensis</i> were determined. They enable genetically stable preservation of many <i>A. platensis</i> strains.</p>