Effect of Dietary Oyster-Extract By-Product on Serum and Liver Lipid Contents in Rats

Seafood consumption has preventative effects against coronary heart disease according to epidemiological evidence gathered from Greenland Inuit and Japanese fi shing villages. Many other studies have also described that seafood consumption assists in protecting against lifestylerelated diseases, including type 2 diabetes, hypertension, and hyperlipidemia. The various benefi cial eff ects of seafood have primarily been attributed to n-3 polyunsaturated fatty acids (PUFAs), such as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). There has been a great deal of research focused on the effi cacy of EPA and DHA in seafood for human health. However, dietary regimes also include EPA and DHA, and in addition to these components whole seafood provides many additional nutrients. Dietary n-3 PUFAs decrease serum triacylglycerol (TG) content, although a meta-analysis indicated that they do not lower serum cholesterol content. Therefore, there is a possibility that the health functions of seafood are not solely related to EPA and DHA. The benefi cial effect of seafood protein may have been masked by EPA and DHA in seafood intake intervention studies. Seafood protein has benefi cial eff ects such as hypocholesterolemic, anti-hypertensive, stimulation of fi brinolysis, and anti-obesity properties in animal stdies. Oysters (Crassostrea gigas) contain many nutrients and are widely used in Japan. Oyster-extract contains main components including zinc, glycogen, and taurine, and oyster-extract powder is marketed as a supplement. Several studies have suggested that oyster-extract powder suppresses the initiator action of carcinogens in mice and promotes the recovery of proximal tubular epithelial cell function in p-aminophenol-induced nephrotoxicity in rats . Recently, the matter of food by-product disposal had become a concern. Thereafter, it is also expected that the effective usage of Original Article