抄録
The nutritive quality of the adductor protein of Japanese pearl-oyster, Pinctada fucata, was examined in terms of amino acid composition and digestibility. Results obtained are summarized as follows.
(1) The amino acid composition of the adductor protein was similar to that of fish muscle and short necked clam muscle.
(2) Chemical score and essential amino acid index were derived from the amino acid composition. In reference with whole egg protein, the two values were found 61 and 80 respectively. In reference with HALVER's formula for rainbow trout feed, the two values were 80 and 98 alternatively.
(3) The adductor protein was further examined with respect to digestibility by both in vitro and in vivo tests. There was some 80% of trypsin-susceptible linkage in the protein seen to be cleaved within a 4-5 hour interval at 37°C, whereas only 20 minutes were sufficient for casein to reach the same level. On the other hand, in vivo digestibility estimated on feeding carps was 87%.
(4) Thus, the high digestibility on carp as well as the high essential amono acid index in reference with HALVER's formula for rainbow trout suggests the due consideration of a profitable applicabilitv of the adductor protein to fish feed.
