Dry rot species of fungi cause brown rot decay, preferentially removing cellulose and hemicellulose from the timber leaving a brittle matrix of modified lignin. The term "dry rot" is somewhat misleading, as both species of fungi "Serpula lacrymans" and "Meruliporia incrassata" require an elevated moisture content to initiate an attack on timber (28–30%). Once established, the fungi can remain active in timber with a moisture content of more than 20%. At relative humidities below 86 percent, growth of "Serpula lacrymans" is inhibited, but it can stay dormant at relative humidities down to 76 percent. These relative humidities correspond to equilibrium moisture contents
Atromentic acid compound to p-hydroxyphenylacetic acid and oxalic acid. Atromentic acid Atromentic acid is a red-organge pigment found in fungi within the Boletales group. It is the precusor to variegatic acid and xerocomic acid, and is preceded by atromentin. As an example, it is isolated from "Serpula lacrymans". It is soluble in methanol. Variants include homoatromentic acid. This pigment has been studied and elucidated by Wolfgang Steglich and colleagues over decades . When atromentin is oxidised with hydrogen peroxide a yellow product is produced. A sodium hydroxide solution is also yellow, but when this is neutralized with acid the red atromentic acid