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Scallops (Patinopecten yessoensis) are extensively cultured and landed in Japan. During the processing of scallops, large amounts of internal organs and shells are discharged as industrial wastes. To reduce the burden on the environment, effective utilization and disposal methods of the wastes are required. Therefore, we have screened for useful materials in scallop internal organs, and found ultraviolet (UV) absorbing compounds from scallop ovaries. Based on UV absorption, electrospray ionization-mass spectrometry (ESI-MS), ESI-MS/MS, and nuclear magnetic resonance (NMR) spectra, three UV absorbing compounds were identified as mycosporine-like amino acids (MAAs): shinorine, porphyra-334 (P-334), and mycosporine-glycine. To investigate whether MAAs can act as a UV protector for human cells, we examined the protective effects of the three MAAs on human fibroblast cells from UV irradiation. All of the three examined MAAs protected the cells from UV-induced cell death. In particular, mycosporine-glycine had the strongest effect. Further, we found a promotion effect of MAAs on the proliferation of human skin fibroblast cells. From these results, it was found that the three MAAs isolated from scallop ovaries have a protective effect on human cells against UV light. MAAs have potential applications in cosmetics and toiletries as a UV protectors and activators of cell proliferation.

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The fatty acid compositions of lipids from two species of Crinoidea and two species of Ophiuroidea have been investigated with open‐tubular gas chromatography. About 5–10% of tetracosahexaenoic acid was found in total fatty acids from all the samples, and the structure was determined as all‐cis‐6,9,12,15,18,21‐tetracosahexaenoic acid [24∶6(n−3)] by13C‐NMR of the methyl esters and mass spectrometric analyses of the methyl esters, the pyrrolidides and the ozonolysis products. The 24∶6(n−3) was concentrated in the polar lipids rather than neutral lipids. The n−3 hexaenoic structure suggested chain elongation of 22∶6(n−3) as the source.The 5‐olefinic acids (5−18∶1, 5−20∶1, 5,11‐ and 5,13−20∶2) were low in Crinoidea (0.2–1.3%) but were present in higher levels (2.5–5.2%) in Ophiuroidea. Polyunsaturated acids found other than 24∶6(n−3) were 20∶4(n−6), 20∶5(n−3) and 22∶6(n−3) as major components and 16∶3(n−3), 18∶2(n−6), 18∶3(n−6), 18∶3(n−3), 18∶4(n−3), 20∶2(n−9), 20∶2(n−6), 20∶3(n−6), 20∶3(n−3), 21∶5(n−3) and 22∶5(n−3) as minor components in all the samples.

The gel strength of surimi made from Alaska pollock, common carp, grass carp, and silver carp was determined and compared for different incubation temperatures and periods. Gel strength and setting of the 3 freshwater fish species were inferior to that of Alaska pollock. Effects of the protein concentration, heating temperature and heating period on the gel strength were evaluated and compared utilizing the response surface methodology. Models for the breaking force and breaking distance of the surimi of the 4 species were established. Protein concentration was the major factor affecting the gel strength. Effects of heating temperature and heating period had differed somewhat among the surimi of the 4 species.