The Effect of Salt Shock on Growth and Pigment Accumulation of Dunaliella Salina

Mahsa Yazdani; Omid Tavakoli

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arXiv · 1911.11840

The Effect of Salt Shock on Growth and Pigment Accumulation of Dunaliella Salina

Mahsa Yazdani·Omid Tavakoli

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Abstract

Dunaliella Salina is a halotolerant microalga with great pharmaceutical and industrial potential, which commonly exists in hypersaline environments. Moreover, it is the best commercial source of beta-carotene (which has high anti-oxidant properties) in comparison to other microalgae. In this study, we investigated growth and accumulations of chlorophyll a and b, beta-carotene, and carotenoid after salt shock in 1, 1.5, 2, 2.5, 3 M concentrations of NaCl. The highest cell growth rate was observed in 1 M salt shock at 22-25 centigrade with a light intensity of 2.084 (mW.cm)^(-2), a light period of 12-12, and at an initial pH of about 7.1. Although the cell growth was enhanced in 1 and 1.5M, further increase in salt content harmed cell growth. The most considerable beta-carotene quantity was attained after 1M salt shock. According to the experimental observations, it was seen that the salt shock in some concentrations is one of the practical approaches to improve the accumulation of pigments. Keywords: beta-carotene, Dunaliella salina, salt shock, pigment accumulation.

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Mahsa Yazdani, Omid Tavakoli. 2019-11-26. The Effect of Salt Shock on Growth and Pigment Accumulation of Dunaliella Salina. https://arxiv.org/abs/1911.11840

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