Characterization of carotenoprotein from different shrimp shell waste for possible use as supplementary nutritive feed ingredient in animal diets

Carotenoproteins from four different shrimp shell wastes Penaeus monodon, Parapenaeopsis stylifera, Metapenaeus affinis and Nematopalemon tenuipes were extracted with the aid of papain enzyme and characterized by their protein, amino acid and carotenoid content of the shell wastes and the antioxidant activities like DPPH, FRAP, ABTS radical scavenging activity and reducing power assay of the carotenoprotein. Higher protein content of 9.8 g 100 g−1 and 9.2 g 100 g−1 was recovered from shell waste of Penaeus monodon and Parapenaeopsis stylifera respectively along with highest carotenoid content of 114 ± 0.02 μg g−1 in Parapenaeopsis stylifera followed by 100.6 ± 0.02 μg g−1 from the shell waste of Metapenaeus affinis. Highest antioxidant activity was found in the carotenoprotein extracted from the shell waste of P. stylifera which suggest that the antioxidant activity of carotenoids followed a concentration dependent pattern. The amino acid profile showed that carotenoprotein is a rich source of essential amino acids such as glutamic acid, aspartic acid, lysine and leucine. Among shell wastes, P.stylifera shell waste was calculated to be superior as it contained higher amount of essential amino acids and exhibited higher antioxidant activity in terms of protein, carotenoid as well as radical scavenging and reducing power and it could serve as a supplementary nutritive feed ingredient in animal diets. This would help in utilization of crustacean (shrimp) shell waste for formulating low cost feed for ornamental fish and also encourage shrimp processing industries to utilize of the same in order to control pollution of land and water.