Avaliação do crescimento de Limnospira platensis (Espirulina) com o uso de extratos vegetais de Camellia sinensis e Lemna minor

Abstract

With the aim of developing a nutritious and economical culture medium for the production of Limnospira platensis (spirulina), four culture media were prepared: one formulated solely with NPK fertilizer plus salts (medium X), two based on NPK fertilizer plus plant extracts of Lemna minor (Lentil medium) and Camellia sinensis (Green Tea medium), and one base medium (Zarrouk). After analysis, it was observed that all alternative media based on NPK fertilizer were able to sustain the growth of Limnospira platensis at biomass levels similar to or even higher than the standard Zarrouk medium, provided the cultivation period was sufficiently long. At the end of the experiment, it was observed that the Zarrouk medium presented the highest crude protein content, differing significantly from the other media; the media containing plant extracts did not differ from each other, while medium X presented the lowest value. After testing the toxicity of spirulina cultivated in different culture media, it was observed that there was lower survival in the control treatment compared to all treatments containing Limnospira platensis extract, presenting an average of 65.5 ± 18.0%, while the extracts from media X, CV, Z, and L showed average survival rates of 97.1 ± 4.35%, 97.7 ± 4.25%, 97.1 ± 4.35%, and 100.0 ± 0.0%, respectively. Finally, it is concluded that alternative media based on NPK and plant extracts are technically viable and economically advantageous for spirulina production, with a trade-off between growth rate and final productivity defining production strategies adapted to different industrial objectives.