Fungi, polyunsaturated fatty acids

Potassium sorbate is a polyunsaturated fatty acid salt. It is used to inhibit molds, yeasts, and fungi in many foods, including cheese, wine, and baked goods. It is the potassium salt of sorbic acid. 

LOXs catalyse the addition of dioxygen to methyl-interrupted cis double bond [(Z,Z)-pentadiene] in a polyunsaturated fatty acid to produce a hydroperoxy fatty acid containing a Z,E conjugated double bond system. Where multiple pentadienes occur in a single molecule such as arachidonic acid, position-specific oxygenation can take place, resulting in the production of 5-, 12- or 15-hydroperoxyeicosa-tetraenoic acids. These hydroperoxy acids may be subsequently converted into other oxylipins by enzymic or non-enzymic reactions [3]. Table 1 shows some examples of LOX products from fungi. 

Figure 9.8 Biosynthetic pathway of polyunsaturated fatty acids in fungi. DS-n = desaturase functioning at the designated C atom EL, elongase. The DS-17 is a desaturase so far only...

Ellenbogen, B.A., Aaronson, S., Goldstein, S. and Belsky, M. (1969) Polyunsaturated fatty acids of aquatic fungi possible phytogenetic significance. Comp. Biochem. Physiol. 29, 805-811. 

Effect of Polyunsaturated Fatty Acids and Enthomopatogenic Fungi... 

The fatty acid compositions of fungi have been extensively reviewed (Shaw, 1966 Wassef, 1977 Weete, 1980). Fungi produce saturated and unsaturated aliphatic acids of 10 to 24 carbons in chain length. Palmitic is the major saturated acid, oleic the main monoenoic acid and linoleic the most common polyunsaturated acid. 

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