Gayana: Botanica (Jan 2003)
PRODUCCION DE PIGMENTOS Y PROTEINAS DE LA CIANOBACTERIA ANABAENA PCC 7120 EN RELACION A LA CONCENTRACION DE NITROGENO E IRRADIANCIA PIGMENT AND PROTEIN PRODUCTION OF THE CYANOBACTERIUM ANABAENA PCC 7120 IN RELATION TO NITROGEN CONCENTRATION AND IRRADIANCE
Abstract
Algunas cianobacterias del género Anabaena son productoras de pigmentos de interés comercial. Este artículo documenta el efecto de la concentración de nutrientes en función del NaNO3 a 0, 1, 2, 4 y 8 mM y de la irradiancia a 78, 156 y 238 µmol m-2 s-1, sobre el contenido de proteínas y pigmentos de Anabaena PCC 7120 en cultivos discontinuos. El crecimiento de la cianobacteria fue poco afectado por la concentración de nitrato, sin diferencia significativa entre 1 y 8 mM (p Cyanobacteria of the genus Anabaena produce pigments of commercial value. The present work reports the effect of nitrogen nutrient concentration (0, 1, 2, 4, and 8 mM NaNO3) and irradiance (78, 156 and 238 µmol m-2 s-1 ) on growth, pigment and protein content in Anabaena PCC 7120 in batch cultures. Growth of the cyanobacterium was little affected by nitrate concentration, with no significant differences between 1 and 8 mM (p< 0,05). However, a concentration of 8 mM gave rise to the highest levels of phycocyanin (174 ± 2 µg ml-1), chlorophyll a (17.4 ± 1.2 µg ml-1), protein (563 ± 2 µg ml-1) and carotenoids (4.5 ± 0.3 µg ml-1). Although cell densities were highest (117 (± 11) x10(6) cell ml-1) at 78 µmol m-2 s-1, maximum levels of protein and pigments were achieved at 156 µmol m-2 s-1. The number of heterocystes per trichome decreased with increasing nutrient concentration. Biomass production of Anabaena PCC 7120 enriched with phycocyanin, chlorophyll a, and protein was enhanced in a saturating-nutrient medium and a irradiance between 78 and 156 µmol m-2 s-1
