MOLECULE

lsoprene

Isoprene, also known as 2-methyl-1,3-butadiene, belongs to the class of organic compounds known as branched unsaturated hydrocarbons. These are hydrocarbons that contains one or more unsaturated carbon atoms, and an aliphatic branch. It is a common organic compound with the formula CH2=C(CH3)‚àíCH=CH2. In its pure form it is a colorless volatile liquid. It is produced by many plants and animals (including humans) and its polymers are the main component of natural rubber. C. G. Williams named the compound in 1860 after obtaining it from thermal decomposition (pyrolysis) of natural rubber. He correctly deduced the empirical formula C5H8 (https://doi.org/10.1098/rspl.1859.0101). Isoprene is produced and emitted by many species of trees (major producers are oaks, poplars, eucalyptus, and some legumes). Isoprene is made through the mevalonic acid pathway in the cytosol and also, in eubacteria, green algae and the plastids of superior plants, through the methyl-erythritol 4-phosphate pathway (MEP pathway, also called the non-mevalonate pathway). Isoprene has been detected, but not quantified, in a few different foods, such as carrots, sweet oranges, and wild carrots. Isoprene has also been detected as a volatile component of cannabis samples (PMID: 26657499).