What is algae culturing?

We cultivate (grow) algae in sterile, nutrient-enriched culturing medium under controlled light and temperature conditions. To establish an algal culture, we start by isolating a single algal cell from an environmental sample collected from a stream or a lake. Isolation of algae is a long microbiological process that may take several months, until the culture of a single algal species is established in lab conditions. Some algae are very sensitive and challenging to grow in the lab, but we have been successful in isolating green algae and cyanobacteria from streams in California. Below, you will see five glass tubes with algal cultures. Notice the different colors of the algal cultures and the oxygen bubbles the algal photosynthesis produces. Click on each tube to see the cells growing inside and the view of the habitat where the alga was collected. The algae from left to right are:
(1) Palmella (green alga) green cells;
(2) Palmella red cells which contain the additional red pigment carotenoid, which acts as sunscreen and protects the cell from UV light;
(3) Microcoleus filaments (cyanobacterium);
(4) Haematococcus (green alga) red cells which contain astaxanthin, a powerful antioxidant carotenoid;
(5) Anabaena filaments (cyanobacterium). Keep in mind that many cyanobacteria produce toxins, including both species illustrated here.