Protein and amino acid contents in the crab, Chionoecetes opilio

Total protein, by the Kjeldahl method, and amino acid content, by HPLC, were determined in crab samples. Proteins were determined in the shell and in the discard meat, separately. C method was used to analyse the amino acids in dried crab shells after derivatization with phenylisothiocyanate. The resulting amino acids were chromatographed on an ODS2 column with UV detection at 254 nm. The mobile phase was a mixture of 0.14 M sodium acetate buffer, pH 6.2, containing 0.05% triethylamine and 60:40 (v/v) acetonitrile–water, at a flow rate of 0.9 ml min−1. The amino acids found at highest concentrations were arginine, lysine, glutamic acid and serine.