초록
<P><B>Abstract</B></P> <P>Microalgae have great potential as alternative productive platforms for sustainable production of bioenergy, food, feed and other commodities. Process optimization to realize the claimed potential often comprises strains selection and improvement and also developing of more efficient cultivation, harvesting and downstream processing technology. In this work we show that inoculation with the bacterium <I>Rhizobium</I> strain 10II resulted in increments of up to 30% in chlorophyll, biomass and lipids accumulation of the oleaginous microalgae <I>Ankistrodesmus</I> sp. strain SP2-15. Inoculated cultures have reached a high lipid productivity of up to 112mgL<SUP>−1</SUP> d<SUP>−1</SUP> after optimization. The resulting biomass presented significant levels of Ω3 fatty acids including stearidonic acid, suggesting potential as an alternative land-based source of essential fatty acids.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Bacterial strains were isolated from laboratory-acclimated microalgae cultures. </LI> <LI> <I>Rhizobium</I> strain 10II is likely a general microalgae-growth promoter. </LI> <LI> Growth promotion appears to be mediated by indol 3-acetic acid and B12. </LI> <LI> Microalgae inoculation with strain 10II resulted in up to 30% increment in biomass. </LI> <LI> Oil productivity of up to 0.1gL<SUP>−1</SUP> d<SUP>−1</SUP> was obtained after optimization. </LI> </UL> </P>