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Of these, Co, Cu, Fe, Ni, and Zn are trace elements required in small amounts for enzyme and redox reactions essential in plant development. [2] However, past a certain threshold they become toxic. The other heavy metals listed are considered toxic at any concentration and can bioaccumulate, posing a health hazard to humans if consumed. [6]
A hyperaccumulator is a plant capable of growing in soil or water with high concentrations of metals, absorbing these metals through their roots, and concentrating extremely high levels of metals in their tissues. [1] [2] The metals are concentrated at levels that are toxic to closely related species not adapted to growing on the metalliferous ...
The plant roots must absorb the heavy metal. The plant must chelate the metal to both protect itself and make the metal more mobile (this can also happen before the metal is absorbed). Chelation is a process by which a metal is surrounded and chemically bonded to an organic compound. The plant moves the chelated metal to a place to safely store it.
Plant nutrition is a difficult subject to understand completely, partially because of the variation between different plants and even between different species or individuals of a given clone. Elements present at low levels may cause deficiency symptoms, and toxicity is possible at levels that are too high.
Phytochemicals are chemicals of plant origin. [1] Phytochemicals (from Greek phyto, meaning "plant") are chemicals produced by plants through primary or secondary metabolism. [2] [3] They generally have biological activity in the plant host and play a role in plant growth or defense against competitors, pathogens, or predators. [2]
Oxalic acid and oxalates are present in many plants and in significant amounts particularly in rhubarb, tea, spinach, parsley, and purslane. Oxalates bind to calcium, magnesium and iron, preventing their absorption in the human body. [6] Glucosinolates prevent the uptake of iodine, affecting the function of the thyroid and thus are considered ...
Solanine is a glycoalkaloid poison created by various plants in the genus Solanum, such as the potato plant. When the plant's stem, tubers, or leaves are exposed to sunlight, it stimulates the biosynthesis of solanine and other glycoalkaloids as a defense mechanism so it is not eaten. [12] It is therefore considered to be a natural pesticide.
Toxicity is the degree to which a chemical substance or a particular mixture of substances can damage an organism. [1] Toxicity can refer to the effect on a whole organism, such as an animal, bacterium, or plant, as well as the effect on a substructure of the organism, such as a cell (cytotoxicity) or an organ such as the liver (hepatotoxicity).