Growth and chemical composition of Spirulina maxima and Spirulina platensis biomass at different temperatures

The influence of temperature on growth and biomass composition of two speci es of Spirulina, S. maxima and S. platensis used for food was studied. A 4L fermenter with temperature and agitation control was used to cultivate bot h species. Under continuous light, maximum cell production of 2.4 g l(-1) w as verified for both cultures studied at temperatures above 25 degrees C: S . maxima (30 degrees C and 35 degrees C) and S. platensis (25 degrees C and 30 degrees C). An accentuated lag phase was observed for all cultures at l ower temperatures (15-20 degrees C), and a maximum biomass production of 1. 5 g l(-1) was achieved. It was also observed that an increase of temperatur e caused a marked decrease in protein content, while carbohydrate synthesis was stimulated. The concentration of gamma-linolenic acid varied from 11-1 6% for S. maxima and from 12-14% for S. platensis, at the optimum growth te mperatures. Greater culture volumes were also studied in order to compare t he performance of glass and plastic containers. At optimum growth temperatu re, S. maxima produced the same cell growth and similar final biomass compo sition.