Richard Martin Willstätter (1872–1942) was a German chemist who received the 1915 Nobel Prize in Chemistry for his work on chlorophyll and on anthocyanins (red, blue, and violet plant pigments). He recognized that there were two major types of chlorophyll in land plants. They differ from each other in details of their molecular structure and absorb slightly different wavelengths of light. The most common type is chlorophyll-a, making up about 75 percent of the chlorophyll in green plants. It is also found in cyanobacteria (formerly known as blue-green algae) and in more complex photosynthetic cells. Chlorophyll-b is an accessory pigment present in plants and other complex photosynthetic cells; it absorbs light energy of a different wavelength and transfers it to chlorophyll-a for ultimate conversion to chemical energy.
- Nobel Foundation. Richard Willstätter – Biography.