FN Archimer Export Format PT J TI Development of a brown internal coloration in the scallop shell (Pecten maximus): study of microstructural characteristics and analyses of crystal organic matrices BT AF Larvor, H. Cuif, J.P. DEVAUCHELLE, Nicole Dauphin, Y Denis, A Gautret, P Marin, F AS 1:1;2:2;3:1;4:2;5:2;6:2;7:2; FF 1:;2:;3:PDG-DS;4:;5:;6:;7:; C1 IFREMER Brest, DRV-RA, Laboratoire PMDC, BP 70, F - 29280 Plouzane, France Université de Paris XI, Bat 504, Paléontologie, F - 91405 Or say Cédex, France C2 IFREMER Brest, DRV-RA, Laboratoire PMDC, BP 70, F - 29280 Plouzane, France Université de Paris XI, Bat 504, Paléontologie, F - 91405 Or say Cédex, France SI BREST SE PDG-DS TC 0 UR https://archimer.ifremer.fr/doc/00048/15929/13355.pdf LA English DT Article AB Calcification abnormalities linked to a brown coloration of the internal layer of the valves have been observed on scallops - Pecten maximus - in different rearing sites of Brittany. Scanning electronic microscopic (SEM) observations demonstrate that the brown pigmentation is associated with various modifications of the foliated microstructure of the internal layer of the shell. Very brown shells have been compared to healthy white shells with different methods. According to the amino acid analyses, the production of the soluble organic matrices appears to be preserved in the diseased shells. A small but significant decrease in the aspartic acid content has been observed in the insoluble organic matrix of the brown shells. The Ca content is the same in the two types of shells, but modifications of the Na, Mg, P, S and Zn contents have been noticed. Moreover, the preparative process for the organic matrices study demonstrates that the red brown pigmentation is exclusively located in the insoluble matrices. Finally, even after HCI hydrolysis for amino acid study, a deep brown residual can still be noticed, demonstrating the high chemical resistance of the brown red pigment. More than a disturbance in the calcification process itself, the crystal disturbance within the internal brown layer of shells appears to be due to the production of a brown compound clearly associated with the crystalline envelopes. PY 1996 SO Bulletin de I'lnstitut océanographique PU Musee Oceanographique de Monaco ID 15929 ER EF