Physiological response of Nannochloropsis sp. to saline stress in laboratory batch cultures

• DOI: 10.1007/s10811-013-0060-1
• Publication Date: 2013-06-12T04:18:20Z
• Authors: A. J. Martínez-Ro...; H. V. Perales-Vela; R. O. Cañizares-V...; G. Torzillo
• Keywords: Photobioreactor

In the present paper, we investigated the physiological response of the marine microalga Nannochloropsis sp. to salt stress (13, 27, 54, and 81 g L-1 NaCl). Increasing the sodium chloride concentration caused up to a 70 % decrease in the chlorophyll a concentration, cell growth, and net photosynthesis rate. The chlorophyll a fluorescence measurements indicated a strong reduction in the effective quantum yield of photosystem II (-60 %) and an increase in nonphotochemical quenching when the cells were exposed to NaCl concentrations greater than 27 g L-1 (control). In contrast, the specific lipid content increased up to 80 % when the sodium chloride concentration was increased from 27 to 54-81 g L-1. These results are relevant for the outdoor cultivation of this microalga using open photobioreactors, in which microalgae are subjected to strong changes in salinity concentration caused by water evaporation.