Catechol one of the main natural phenols in argan oil and is a component of castoreum, a substance from the castor gland of beavers, used in perfumery. It is also found in "Agaricus bisporus". Catechol moieties are also found widely within the natural world. Arthropod cuticle consists of chitin linked by a catechol moiety to protein. The cuticle may be strengthened by cross-linking (tanning and sclerotization), in particular, in insects, and of course by biomineralization. Catechols such as DHSA are produced through the metabolism of cholesterol by bacteria such as "Mycobacterium tuberculosis". Urushiols are naturally existing organic compounds that have the
Pith and substance to one of them will deal with the issue. For example, if the provision in question has no relation to the regulatory scheme, the question of its validity may be quickly answered on that ground alone. The pith and substance doctrine as applied in the jurisprudence of the Judicial Committee of the Privy Council, effectively the British Imperial Court of Appeal, has been carried to other Commonwealth federations. It is used in the Indian Constitution. It was also used in Northern Ireland under the Government of Ireland Act 1920. The substance of the doctrine has been cast in statutory form