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
Oily fish seafloor, whereas oily fish are pelagic, living in the water column away from the bottom. Oily fish meat is a good source of vitamins A and D, and is rich in omega-3 fatty acids (white fish also contain these nutrients but at a much lower concentration). For this reason the consumption of oily fish rather than white fish can be more beneficial to humans, particularly concerning cardiovascular diseases; however, oily fish are known to carry higher levels of contaminants (such as mercury or dioxin) than whitefish. Among other benefits, studies suggest that the omega-3 fatty acids in oily fish may