Potential of benthic microalgae of the caribbean sea as food in mariculture

Abstract

-For the development of marine aquaculture in the Caribbean, the availability of local benthic microalgae as food is desirable. In this work, 6 strains of benthic microalgae were isolated and their potential for use in aquaculture was evaluated by analyzing their size, cell density, growth rate, proximal composition, as well as their capacity to produce biomass on plates under culture conditions indoor and outdoor. Three diatoms (Cylindrotheca closterium, Entomoneis alata, and Plagiotropis lepidoptera), two cyanobacteria (Komvophoron crassum and Synechococcus sp.) and one chlorophyte (Tetraselmis chuii) were isolated and described. The cyanobacteria had the smallest cell sizes, while the diatoms had the largest. Under planktonic culture conditions, the highest algal density was presented by Synechococcus sp. while the highest growth rate occurred in E. alata. Higher protein content and protein/energy ratio were present in diatoms, carbohydrates in Tetraselmis chuii and cyanobacteria, while those of lipids and energy were recorded in the diatoms E. alata and P. lepidoptera. Under benthic culture conditions, the highest biomass production and growth rate was obtained in cyanobacteria and P. lepidoptera. Most of the microalgae exhibited higher values of biomass settled in indoor than outdoor conditions, as well as similar growth rates in both sites. In conclusion, given the size, proximal composition, settled biomass and growth rate, all isolated benthic microalgae have the same potential to be used as food in marine aquaculture.