Spirulina is the name of blue-green algae generally found as mats of microscopical coiled filaments in fresh and brackish waters. Its proteins (60-70 percent of dry mass) consist of 18 different amino acids. Vitamins A, B, E, H are also present, including B12 which is usually found only in animal tissues. Spirulina has a photosynthetic conversion rate of 8 to 10 percent, compared to only 3 percent in land-growing plants such as soybeans. (Enhanced SEM, microscope magnification 800x, image width: 157 micrometers, bar: 20 micrometers)