Avaliação da composição taxônomica de cepas de microalgas coletadas em tanques de psicultura e cultivadas com vinhaça

Abstract

Microalgae are photosynthetic microorganisms that have been outstanding in science because they are nutritional sources. The objective of this work is to identify the taxonomic composition and growth in cultivation of microalgae strains, collected in tilapia breeding tanks, in culture media with different concentrations of sugarcane vinasse. The microalgae strains were collected in a tilapia pond in the municipality of Glória de Dourados, MS and grown in culture medium containing NPK (20-05-20) g L-1 mineral supplement with different concentrations of vinasse: NPK + vinasse (1%), NPK + vinasse (10%) and N.P.K + vinasse (50%). Four strains that showed higher growth during cultivation were chosen: Chlorella sp., Scenedesmus quadricauda, Pediastrum duplex and Chroococcus sp. The data obtained in the different treatments were analyzed in a comparative test of Tukey means at 1% of significance (α = 0,01). Growth rate and generation time were verified. The species Chlorella sp. it showed the highest specific growth rate (0.181 d-1) and shortest generation time (3.82 d-1), followed by Scenedesmus quadricauda, both in the treatments with 10% concentration of vinasse. The species Pediastrum duplex and Chroococcus sp. demonstrated a much lower performance compared to the other two species. The microalgae Chlorella sp. and Scenedesmus quadricauda species showed the highest growth in concentrations of 1% and 10% of vinasse supplementation. Both strains showed expressive cell growth and consequently high biomass production.