Aim of this study: The major aim of this work was to consistently optimize the production of biomass of the dinoflagellate Karlodinium veneficum and evaluate its extracts biotechnological potential application towards food, nutraceutical or/and pharmaceutical industries.
Methods and results: A successful approach of biomass production of K. veneficum CCMP 2936 was optimized along with the chemical characterization of its metabolite profile. Several temperatures (12, 16, 20, 25, 30°C), L1 nutrient concentrations (0.5×, 2×, 2.5×, 3×) and NaCl concentrations (20, 25, 30, 40 g L-1 ) were tested. The growth rate was maximum at 16°C, 2× nutrient concentration and 40 g L-1 of NaCl; hence, these conditions were chosen for bulk production of biomass. Methanolic extracts were prepared, and pigments, lipids and phenolic compounds were assessed; complemented by antioxidant and anti-inflammatory capacities, and cytotoxicity. Fucoxanthin and derivatives accounted for 0.06% of dry weight, and up to 60% (w/w) of all quantified metabolites were lipids. Said extracts displayed high antioxidant capacity, as towards assessed via the NO•- and ABTS•+ assays (IC50 = 109.09 ± 6.73 and 266.46 ± 2.25 µgE ml-1 , respectively), unlike observed via the O2 •- assay (IC25 reaching 56.06 ± 5.56 µgE ml-1 ). No signs of cytotoxicity were observed.
Conclusions: Karlodinium veneficum biomass production was consistently optimized in terms of temperature, L1 nutrient concentrations and NaCl concentration. In addition, this strain appears promising for eventual biotechnological exploitation.
Significance and impact of the study: This work provides fundamental insights about the growth and potential of value-added compounds of dinoflagellate K. veneficum. Dinoflagellates, as K. veneficum are poorly studied regarding its biomass production and added-value compounds for potential biotechnological exploitation. These organisms are difficult to maintain and grow in the laboratory. Thus, any fundamental contribution is relevant to share with the scientific community.
Keywords: anti-inflammatory; antioxidant compounds; dinoflagellate; methanolic extracts; pigments; sequential optimization.
© 2021 The Society for Applied Microbiology.