초록
<P>The goal of this research is the investigation of a way to maximize the production of docosahexaenoic acid (DHA) and β-carotene by optimizing the culture conditions of their sources, microalgae <I>Schizochytrium limacinum</I> and fungus <I>Blakeslea trispora</I> respectively, in a fermentation medium. The influencing factors in the fermentation process for producing DHA and β-carotene have proven to be: the concentration of carbon source (different glycerol crude and pure concentrations) for both of them, and in particular temperature for DHA and pH for β-carotene. Testing the effect of these parameters was determined: biomass, DHA and β-carotene concentration. The highest production by <I>S. limacinum</I> was obtained at 25 °C, while using a quantity of 90 g/L of glycerol (crude or pure) as a carbon source. Temperature was the main factor that influenced the biosynthesis of DHA. The quantification of DHA was made by GC–MS chromatography, followed by a purification process, with the end result of DHA in pure phase. The maximum quantities for β-carotene production were obtained with pH 7 and 60 g/L of crude glycerol. The results highlight the possibility of using crude glycerol as a low-cost substrates for growth of microalgae <I>S. limacinum</I> and of fungus <I>B. trispora</I> in order to obtain the crucial molecules: docosahexaenoic acid and β-carotene.</P>