The oxidative balance in the hydrophilic medium during development of the microalga Phaeodactylum tricornutum.

CABRERA, J.; GONZÁLEZ PAULA M.; PUNTARULO, S.

Buenos Aires

Otro; Reunión conjunta de sociedades de biociencias; 2017

SAIC, SAIB, SAI, SAA, SAB, SAFE, SAFIS, SAH, SAP

The oxidative status in the hydrophilic medium during the culture under laboratory conditions of the template diatom Phaeodactylum tricornutum was studied. The curve of growth of the microalgae was characterized. The classic three phases of development, LAG, exponential (EXP) and stationary (ST), were identified by cell counting (under optical microscope) and optical density (spectrophotometrically) at room temperature (18ºC). For each phase, ascorbyl radical (A●, measured by electronic paramagnetic resonance, EPR) and ascorbate (AH−, measured by HPLC) content were measured. The A● content was significantly increased by 2.7-fold, as compared to values in LAG phase, in both EXP and ST phases. The AH− content in the EST phase, as compared either to LAG phase (0.108± 0.003 nmol/106 cell) or to the EXP phase (0.11 ± 0.01 nmol/106 cell), was significantly increased by 70%. The A●/AH− index reflects the oxidative condition of the hydrophilic medium in the cells. The obtained values for this index were significantly different among the three phases (p