Corrêa, P.S.Freitas, M.M.A.Caetano, N.2024-03-192024-03-192023Corrêa, P.S., Freitas, M.M.A., & Caetano, N.S. (2023, August 20-26). Experimental design to otpimize Bold's basal medium to increase biomass and pigment production in three microalgae species [Poster]. 8th European Phycological Congress, Brest, Francehttp://hdl.handle.net/10400.22/25198(Introduction) The great biotechnological potential of microalgae has aroused the interest of many industrial sectors. With biomasses rich in pigments, lipids, proteins and several other compounds, these microorganisms are a potential source of bioactive molecules for multiple applications. According to the literature, Chromochloris zofingiensis is an interesting source of carotenoids, specially astaxanthin 1,2 , Koliella longiseta is mainly reported as a rich source of eicosapentaenoic acid (EPA, ω-3) and arachidonic acid (ARA, ω-6) 3, while Schizomeris leibleinii is mainly studied for wastewater treatment 4,5. The imposition of abiotic stress by changing culture conditions (e.g. nutrient concentration in the culture medium, temperature, light irradiance, among others) directly influences growth and is able to modulate biomass composition. An experimental design was proposed to evaluate the effect of salinity and concentration of nitrate, ferrous sulphate and phosphate on growth and production of carotenoids and chlorophylls in these species. Higher salinity and ferrous sulphate concentration increased the final biomass concentration almost threefold in C. zofingiensis and twofold in S. leibleinii when compared to their controls. Meanwhile, K. longiseta was able to double its biomass concentration only by changing nitrate concentration in the medium. Regarding pigment production, higher carotenoids content was found in C. zofingiensis (3.16 mg·g-1) cultivated in unmodified BBM (Bold´s Basal Medium) and S. leibleinii (3.09 mg·g-1) cultivated under nitrogen limitation and with higher salinity and ferrous sulphate concentration. Finally, higher chlorophyll content was observed in K. longiseta (17.77 mg·g-1) cultivated at higher ferrous sulphate concentration and C. zofingiensis (16.24 mg·g-1) cultivated in absence of phosphate and higher ferrous sulphate concentration.engBold's basal mediumBiomass productionPigment productionMicroalgaeconference object