What are unusual fatty acids and their types?

Question

What are unusual fatty acids and their types?

Answer 1

Unusual fatty acids with hydroxyl groups in central positions, together with methyl groups and double bonds, have been found in species of fungi, lichens and slime moulds.

For example, 7-hydroxy-8,14-dimethyl-9-hexadecenoic acid, and structurally related fatty acids, were found in fungal species belonging to the Ascomycetes and Basidiomycetes. 9,10,13- and 9,12,13-Trihydroxyoctadecenoic acids found in beer are derived from microbial fermentation of linoleic acid.