clorofilla

Clorofilla, or chlorophyll, is the group of green pigments essential for photosynthesis in plants, algae, and cyanobacteria. The most common forms in green organisms are chlorophyll a and chlorophyll b; other forms such as chlorophyll c, d, and f occur in various algae and bacteria. Chemically, chlorophyll comprises a porphyrin ring with a central magnesium ion and a long hydrophobic phytol tail that anchors it in membranes.

Chlorophyll absorbs light mainly in the blue and red parts of the spectrum and reflects green, giving plants their characteristic color. In photosynthesis, chlorophyll participates in the light-dependent reactions, capturing photons and driving electron transport to produce ATP and NADPH, which fuel the Calvin cycle to fix carbon dioxide into sugars.

Chlorophyll is synthesized in chloroplasts of plants and algae, and in some bacteria. The biosynthetic pathway involves multiple enzymes, beginning with the formation of ALA and ending with insertion of magnesium into protoporphyrin IX.

In industry and food, chlorophyll is used as a green colorant (commonly labeled as E140). A water-soluble derivative, chlorophyllin, is used as a dietary supplement and cosmetic ingredient, though health claims are limited by evidence.

Chlorophyll degrades under light, heat, or acidic conditions, leading to color loss and the autumn change in leaves as other pigments become visible.

Name origin: from Greek chloros “green” and phyllon “leaf.” It was first isolated in 1817 by Pelletier and Caventou.