Resumen en español

The supply of agricultural fertilizers as nutrient media, lead to a high growth of microalgae, reflecting as an important and efficient source for the production of crops of these organisms. This study evaluated the population growth of Chlorella minutissima under the incidence of NPK and Remital agricultural fertilizers; a first phase was carried out at the University of Córdoba and a second phase in a sector of the Mocarí neighborhood, Montería-Córdoba. Initially an inoculum was required, for this the solid strain was activated in 10 mL of F/2 Guillard medium, then it was brought to volumes of 350 mL and 1.5 L with this same medium under controlled conditions. The second phase corresponded to the realization of the artisan cultivation system where the volume was maximized to 10 L using NPK and Remital agricultural fertilizers separately, taking into account 1 g/L of fertilizer, this was maintained under ambient conditions and constant aeration; counts were performed every 48 hours from the beginning of the culture until the stationary phase. During the first 96 hours there was no increase in the growth of C. minutissima in both treatments, this being the adaptation phase, later the exponential growth of the organism occurred, which began at 144 hours; the experimental units with NPK reached their stationary phase at 432 hours with a density of 5,680,000 cells/mL and those with Remital at 384 hours with 3,120,000 cells/mL. A sigmoidal type curve, characteristic of discontinuous cultures, was observed as a result. The treatments showed different values in both K and Td variables, however, the NPK fertilizer was the treatment with the shortest doubling time 5.85 div/day-1 and the highest growth rate 0.11 day-1. The two treatments with the fertilizers showed a positive cell growth of C. minutissima in an artisan culture system with a volume of 10 L, under conditions of natural light and room temperature, proving to be a good option as nutritive media. The NPK treatment presented the best response in terms of density, growth rate and doubling time. Therefore, NPK is the most recommended treatment when it comes to producing microalgal biomass, of the commercial fertilizers evaluated.