The Analysis of Nutrient Components of Three Brittle Star Species in the North Yellow Sea

Abstract:

Nutrient components of brittle stars Ophiopholis mirabilis, Stegophiura sladeni and Ophiura sarsii vadicola collected in the North Yellow Sea of China were studied. Alive samples were frozen at −70℃, and then dried in a lyophilizer. The results showed that the moisture content of the brittle stars was less than 50%, and it was 41.61% in S. sladeni that was significantly lower than those in the others (P<0.05). The ash content in S. sladeni was 80.70%, which was higher than those of the others (P<0.05). The total amino acid content in the brittle stars was low, and the highest one was in O. mirabilis with 14.90% (P<0.05). The percentage of essential amino acids to the total amino acids (EAA/TAA) of O. mirabilis, S. sladeni and O. sarsii vadicola was 35.37%, 29.58% and 34.97%, respectively. The essential amino acids and flavour amino acids in O. mirabilis were significantly higher than those in the others (P<0.05). Furthermore, the highest amino acids score, chemical score and essential amino acids index were in O. mirabilis. The unsaturated fatty acids in O. mirabilis, S. sladeni and O. sarsii vadicola were 52.91%, 50.03% and 64.31%, respectively, and the highest one was in O. sarsii vadicola (P<0.05). However, the lowest saturated fatty acid was in O. sarsii vadicola with 13.32% (P<0.05). All species were rich in mineral element. The Ca and Mg contents in O. sarsii vadicola were significantly higher than those in the others (P<0.05), which were 348000 mg/kg and 28500 mg/kg, respectively. The results suggested that these three species are not good protein sources but suitable for developing function food for Ca supplement. The high carbonate content in brittle stars showed that brittle stars are probably important to the ocean carbon sink.