Biomass production and growth performance of Momela Lake’s spirulina (<i>Arthrospira fusiformis</i>) cultured under urea and N: P: K fertilizers as cheaper nitrogen sources

Abstract

Spirulina species are world widely known for their ability to produce high quantities of useful metabolites such as protein, fatty acids and vitamins. One of the major challenges in production of this microalgae is the cost and composition of culture medium. In the present study, effect of two culture media with agricultural fertilizers as nitrogen sources viz. urea containing medium (UM) and N: P: K containing medium (NPKM) on production of a locally found spirulina (Arthrospira fusiformis) was investigated. Zarrouk medium (ZM) was used as a standard, other culture conditions included 67.5 μmol m-2 s-1 radiation, 10 pH and 30 ºC temperature. A. fusiformis was isolated from Momela Lake in Arusha National Park Tanzania. There was no difference (p > 0.05) in mean biomass production (BMmean) and doubling time (DT) between ZM (1.205 g/L, 1.437 days respectively) and UM (1.168 g/L, 1.63 days respectively). Significantly higher (p < 0.05) maximum biomass BMmax production and exponential growth rate (μ) in a sequential order was from ZM (1.844 g/L, 0.483/day respectively), UM (1.6 g/L, 0.425/day respectively) and NPKM (0.57 g/L, 0.273/day). It appeared that the wild-isolated A. fusiformis was able to grow well in less costly UM showing high potential for mass production.© 2019 International Formulae Group. All rights reserved.Keywords: Momela Lake’s spirulina, biomass production, agricultural fertilizers, nitrogen sources