Ayolotu Muyiwa | University of Nigeria, Nsukka (original) (raw)

A legume is a plant in the family Fabaceae, or the fruit or seed of such a plant. Legumes are gro... more A legume is a plant in the family Fabaceae, or the fruit or seed of such a plant. Legumes are grown agriculturally, primarily for their food grain seed, for livestock forage and silage, and as soil-enhancing green manure. Research in crops is often difficult because of generation time, size of the plant and complicated genomes. Scientist therefore make use of "model species" that are easier to work with and use their results to improve crops.
Lotus as an example contains two cyanogenic compounds called linamarin and lotaustralin that are produced from the amino acids valine and isoleucine.
Plants try to defend themselves against slugs and insects and larger herbivores that see them as their next meal. An important defense strategy for plants is the use of chemicals that taste bad or are harmful to the animal so that they rather go somewhere else. Literally thousands of chemicals have been developed in a chemical arms race between plants and the animals that eat them.
An evolutionary ancient plant defense mechanism is the use of cyanogenic glucosides found in a percentage of ferns and higher plant species. These are amino acid derived compounds that are linked to a glucose molecule and stored in plant cells. When animals damage plant leaves, these cyanogenic glucosides are released and come in contact with enzymes in the plant called β-glucosidases. These β-glucosidases will remove the glucose and the chemically unstable amino acid derived compound, called a hydroxynitrile, will dissociate and produce toxic hydrogen cyanide gas (HCN).
Detoxification of cyanide can take place in two ways viz. in vivo and in vitro.
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