EFFECT OF NITROGEN (NITRATE) ON GROWTH, PROTEIN CONTENT, AND ANTIOXIDANT CAPACITY OF THE SPIRULINA SP.

Abstract

Spirulina sp. is a natural product known as a natural source of nutraceuticals and bioactive compounds, responding to the demand of both food and medicinal products. Cultural conditions are the key point to determine the quality of Spirulina’s products. Under the high NaNO₃ concentration supplied Zarrouk medium (5.0 g/L), the dry biomass (0.60 g/L) and the protein content (34.41%) which were higher than those under low NaNO₃ concentration supplied medium (1.25 g/L and 2.5g/L, the antioxidant capacity, protein content, and amino acid profiles were high in both strains of Spirulina sp. from USA and Japan under the cultural condition in which NaNO₃ concentration was of 5.0 g/L. In addition, there was a positive correlation between the total phenolic content and the antioxidant capacity of the two strains of Spirulina sp.