Use of common carp waste for pigment production by Monascus purpureus

Fish processing worldwide generates a large amount of waste that has no further use. In this work, we tested the possible biotechnological use of two waste materials from common carp – waste scales and residues from filleting process. Both sources were subjected to alkaline hydrolysis and subsequently used as a source of nitrogen, phosphorus and other elements for the cultivation of the fungus Monascus purpureus, which is known for the production of pigments with potential in pharmaceutics and other sectors of industry. After 14 day-long cultivation of Monascus purpureus in a medium containing hydrolysate as the sole source of all nutrients except carbon, the extraction of pigments and their further analysis were carried out. It was shown that a simple as well as inexpensive alkaline hydrolysis can be used to prepare a complex culture medium suitable for pigment production using fish waste. Moreover, there is a big potential that this medium would also be suitable for many more biotechnological applications.