어류의 carotenoid에 관한 비교 생화학적 연구의 일환으로서 잉어아과에 속하는 칼납자루 표피의 carotenoid 조성을 분석 비교하고, 칼납자루에 대한 사료 carotenoid의 체내 대사와 체색 개선에 미치는 영향을 검토하기 위하여, lutein, cynthiaxanthin 및 astaxanthin을 각각 첨가한 사료로써 4주간 사육한 결과는 다음과 같다. 칼납자루 표피의 carotenoids의 조성비는 자연산에는 zeaxanthin 47.2%, lutein epoxide 11.4%, diatoxanthin 11.0%, lutein 9.7% 및 zeaxanthin epoxide 8.3%가, 2주간 순치후에는 α-cynptoxanthin 29.9%, zeaxanthin 19.3%, lutein epoxide 13.1%, diatoxanthin 12.0% 및 zeaxanthin epoxide 8.8%가 주성분으로 함유하여 칼납자루에는 zeaxanthin, diatoxanthin, lutein epoxide 및 zeaxanthin epoxide의 대사가 활발하다는 것을 알 수 있었다. 칼납자루 표피의 총 carotenoids 함량은 자연산 1.72㎎%, 2주간 순치후 2.08㎎%로 나타났고, 사육 시험 2주후에는 control구 2.10㎎%에 비하여 lutein 첨가구 2.23㎎%, cynthiaxanthin 첨가구 2.36㎎% 및 astaxanthin 첨가구 2.49㎎%로 carotenoid 첨가구에서 모두 높게 나타났으며, 사육 시험 4주후에는 control구 1.76㎎%, lutein 첨가구 1.95㎎%, cynthiaxanthin 첨가구 1.74㎎% 및 astaxanthin 첨가구 1.72㎎%로 감소하여, carotenoids는 신속하게 축적, 그리고 대사된다는 것을 알 수 있었다. 칼납자루 표피에서의 carotenoids 축적률은 astaxanthin 첨가구가 가장 높게 나타나서 체색 선명화 효과가 컸으며, cynthiaxanthin, lutein 첨가구의 순으로 나타났다. 사육 시험후, 각 carotenoid 첨가구의 총 carotenoids 함량과 조성의 변화에 의한 칼납자루 표피에서의 carotenoids 대사 경로는 lutein이 α-doradexanthin(4-ketolutein)과 β-doradexanthin(4-ketozeaxanthin)을 경유하여 astaxanthin으로 변화하는 산화적 대사과정이 있고, 또한, zeaxanthin을 경유하여 zeaxanthin epoxide로 변화되는 산화적 대사과정이 존재한다. cynthiaxanthin은 diatoxanthin과 zeaxanthin으로 변화하는 환원적 대사과정를 경유하여 zeaxanthin epoxide로 변화하는 산화적 대사과정이 있고, 또한, diatoxanthin, zeaxanthin 및 β-doradexanthin을 경유하여 astaxanthin으로 변화하는 산화적 대사과정이 존재한다. 그리고 astaxanthin은 β-doradexanthin과 zeaxanthin으로 변화하는 환원적 대사과정을 경유한 후 zeaxanthin epoxide로 변화하는 산화적 대사과정이 존재한다. 일반적으로 담수어에는 산화적 대사가 주된 대사이나 환원적 대사도 함께 존재함을 알 수 있었다.
Effects of dietary carotenoids were investigated on metabolism of the carotenoids, and body pigmentation in oily bittering, Acheilognathus koreensis. Two weeks later after depletion, oily bitterings were fed the diets supplemented with either lutein, cynthiaxanthin and astaxathin for 4 weeks. Carotenoids distributed to and metabolized in integument were analyed. The carotenoid isolated from the integument of wild oily bittering, composed of 47.2% zeaxanthin, 11.4% lutein epoxide, 11.0% diatoxanthin, 9.7% lutein and 8.3% zeaxanthin epoxide. Meanwhile, two weeks later after depletion, the carotenoid composed of 29.9% α-crytoxanthin, 19.3% zeaxanthin, 13.2% lutein epoxide, 12.0% diatoxanthin and 8.8% zeaxanthin epoxide. These indicated that zeaxanthin, diatoxanthin. lutein epoxide and zeaxanthin epoxide were actively metabolized in oily bittering. compared to that of other fresh water fish. Total carotenoid content in the integument of wild oily bittering and oily bittering depleted for two weeks was found to be 1.72㎎% and 2.08㎎%, respectively. Two weeks later after treatment of experimental diet, total carotenoids content was increased to 2.23㎎% in lutein. 2.36㎎% in cynthiaxanthin and 2.49㎎% in astaxanthin supplemented group. which were relatively higher than 2.10㎎% in control group. Meanwhile, 4 weeks later, total carotenoids content was decreased to 1.76㎎% in control, 1.95㎎% in lutein. 1.74㎎% in cynthiaxanthin and 1.72㎎% in astaxanthin supplemented groups. These result indicate that dietary carotenoids were rapidly accumulated and then metabolized to certain metabolites shortly after feeding. Body pigmentation effects of the carotenoids due to accumulation of carotenoids in the integument of oily bittering was the most effectively shown in the astaxanthin supplemented group, followed by cynthiaxanthin and lutein supplemented groups. In the integument of oily bittering, dietary carotenoids were presumably biotransformed via either oxidative or reductive pathways as presumed the variation of total carotenoid content and carotenoid composition in all experimental groups. The lutein was oxidized either to astaxanthin via α-doradexanthin and β-doradexanthin, or to zeaxanthin epoxide via zeaxanthin by oxidative pathway. Cynthiaxanthin was converted either to diatoxanthin and zeaxanthin by reductive pathway and then to zeaxanthin epoxide by oxidative pathway, or it was converted to astaxanthin via diatoxanthin. zeaxanthin and β-doradexanthin by oxidative pathway. Astaxanthin was converted to β-doradexanthin and zeaxanthin by reductive pathway and then to zeaxanthin epoxide by oxidative pathway. These results suggest that, oxidative pathway of carotenoids was major metabolic pathway along with reductive pathway in fresh water fish.