Plants
Melatonin has been identified in many plants including Feverfew (Tanacetum parthenium), and St John's wort (Hypericum perforatum). The physiological roles of melatonin in plants involve regulation of their response to photoperiod, defense against harsh environments, and the function of an antioxidant. The latter may be the original function of melatonin in organisms with the others being added during evolution. Melatonin also regulates plant growth by its ability to slow root formation, while promoting above ground growth.
Melatonin has been reported in foodstuffs including cherries to about 0.17-13.46 ng/g, bananas and grapes, rice and cereals, herbs, olive oil, wine and beer.
When bird chicks ingest melatonin-rich plant feed, such as rice, the melatonin binds to melatonin receptors in their brains. No food has been found to elevate plasma melatonin levels in humans.
Read more about this topic: Melatonin
Famous quotes containing the word plants:
“Probably if our lives were more conformed to nature, we should not need to defend ourselves against her heats and colds, but find her our constant nurse and friend, as do plants and quadrupeds.”
—Henry David Thoreau (18171862)
“Brute force crushes many plants. Yet the plants rise again. The Pyramids will not last a moment compared with the daisy. And before Buddha or Jesus spoke the nightingale sang, and long after the words of Jesus and Buddha are gone into oblivion the nightingale still will sing. Because it is neither preaching nor commanding nor urging. It is just singing. And in the beginning was not a Word, but a chirrup.”
—D.H. (David Herbert)
“He who plants a tree
Plants a hope.”
—Lucy Larcom (18261893)