Lactarius repraesentaneus namely repraesentins B and C. These compounds were shown to promote the radicle elongation of lettuce seedlings by 136%, 118% and 184% at 67 ppm, respectively. Other compounds reported in 2006 are repraesentins D, E, and F. Repraesentin E showed the strongest growth promotion activity, 164% at 3.6 µm, of the three compounds toward the radicle elongation of lettuce seedlings. Lactarius repraesentaneus Lactarius repraesentaneus, commonly known as the northern bearded milkcap, the northern milkcap, or the purple-staining milkcap, is a species of fungus in the Russulaceae family. It has a northerly distribution, and is found in temperate regions of North
Purple bacteria Purple bacteria Purple bacteria or purple photosynthetic bacteria are proteobacteria that are phototrophic, that is, capable of producing their own food via photosynthesis. They are pigmented with bacteriochlorophyll "a" or "b", together with various carotenoids, which give them colours ranging between purple, red, brown, and orange. They may be divided into two groups – purple sulfur bacteria (Chromatiales, in part) and purple non-sulfur bacteria (Rhodospirillaceae). In a 2018 paper, it has been suggested purple bacteria be used as a biorefinery. Purple bacteria are mainly photoautotrophic, but are also known to be chemoautotrophic and photoheterotrophic. They can be mixotrophs, capable of