Genotoxicity evaluation of oil prepared from the internal organs of the Japanese giant scallop (<i>Patinopecten yessoensis</i>)

Abstract

Discarded scallop internal organs, especially the hepatopancreas, are rich in n-3 polyunsaturated fatty acids such as eicosapentaenoic acid and docosahexaenoic acid. However, they have not been utilized because of their contamination with toxic substances, such as cadmium (Cd), and the occurrence of diarrheic shellfish toxins (DST). We have successfully prepared a high-quality scallop oil (SCO) from the internal organs of the Japanese giant scallop (Patinopecten yessoensis), including the hepatopancreas without Cd and DST. These pollutants were removed by liquid-liquid partitioning followed by adsorption to active carbon of fine particle size with high pore surface volume. In this study, we prepared SCO from scallop internal organs obtained from two different processing areas (Mutsu and Uchiura bays, Japan), and referred to them as SCO-M and SCO-U, respectively. Genotoxicity of SCO-M and SCO-U was evaluated by the in vitro bacterial reverse mutation test (Ames test) and in vivo micronucleus test in accordance with the Organisation for Economic Cooperation and Development guidelines. SCO-M and SCO-U showed negative results in the Ames test in the presence or absence of metabolic activation with S9 mix. In addition, no genotoxic effects of SCO-M and SCO-U were observed at all tested doses in the micronucleus test. Based on the results of the present study, it can be concluded that SCO-M and SCO-U are safe products in terms of genotoxicity under these experimental conditions.

Single and Repeated Dose 28-Day and 13-Week Toxicity Studies of Oil Prepared from the Internal Organs of the Japanese Giant Scallop (Patinopecten yessoensis) in Mice

“…In contrast, the internal organs of Uchiura bay scallops included hepatopancreas, gonads, gills, and mantles that were collected between August 2017 and September 2017. SCO-M and SCO-U were prepared according to the method described previously [ 22 ]. Soybean oil was obtained from Merck KGaA (Darmstadt, Germany).…”

“…Our previous study showed that administration of SCO-M and SCO-U at a dose of 2000 mg/kg body weight (BW)/day, which is the upper limit dose specified by the OECD Guideline for the Testing of Chemicals No. 474 [ 30 ], did not induce clinical signs or BW changes in ICR mice [ 22 ]. Therefore, 5000 mg/kg BW/day was set as the dose of SCO-M and SCO-U for the single oral dose toxicity study.…”

“…For this reason, the scallop internal organs have not been utilized as sources of EPA and DHA. Recently, we successfully prepared high-quality scallop oil (SCO) that satisfies the specifications for use as food from the scallop internal organs, by removing toxic components, including As compounds, Cd, and DST [ 22 ]. Omega-3 PUFA accounts for 40% of the fatty acid composition of SCO, which is much higher than that of fish oil and krill oil.…”

“…Omega-3 PUFA accounts for 40% of the fatty acid composition of SCO, which is much higher than that of fish oil and krill oil. In this study, we prepared SCO using the previously described method [ 22 ] from the scallop internal organs obtained from two different processing areas and referred to them as SCO-M (SCO from Mutsu bay, Aomori, Japan) and SCO-U (SCO from Uchiura bay, Hokkaido, Japan). Although SCO-M and SCO-U are novel alternative sources of EPA and DHA, the safeties of SCO-M and SCO-U are uncertain due to the presence of toxic substances in hepatopancreas.…”

“…Although SCO-M and SCO-U are novel alternative sources of EPA and DHA, the safeties of SCO-M and SCO-U are uncertain due to the presence of toxic substances in hepatopancreas. Our previous study demonstrated that SCO-M and SCO-U did not exhibit genotoxicity in in vitro (Ames test) and in vivo (micronucleus test) studies [ 22 ]. However, no acute and sub-acute toxicity studies have been carried out in animal models.…”