Differential interference contrast (DIC) light micrograph of the colonial green algae otryococcus braunii? Colonies are held together by a lipid (oily) biofilm as can be seen as oil droplets around the edge of the colony. Typically around 30?0% of the dry weight of a colony is oil. Botryococcus braunii has potential for algaculture because of the hydrocarbons it produces, which can be chemically converted into fuels. Magnification: x475 when printed at 10 centimetres wide at its longest edge.