We explored the frequency response of krill target strength (TS) to understand the Antarctic krill (Euphausia superba) and ice krill (Euphausia crystallorophias) using the stochastic distorted-wave Born approximation (SDWBA) model. The results showed that the distribution of orientation and the fatness factor could significantly impact on the frequency response of TS. Krill TS is clearly depended on acoustic properties, which could affect to estimate the biomass of two krill species. The results provide insight into the importance of understanding TS variation to estimate the Antarctic krill and ice krill biomass, and their ecology related to the environmental features in the Southern Ocean.

본 연구는 동결 건조한 krill (Euphausia superba) meal을 함량별 섭취시켰을 때 7주령된 Sprague Dawley계 수컷 흰쥐의 혈청 중 alkaline phosphatase (ALP), aminotransferase (AST, ALT) 및 lactate dehydrogenase (LDH) 등 혈청 간 기능 효소활성과 장기 조직의 불소 함량에 미치는 영향을 확인하였다. 기본식이를 급여한 대조군인 CG군을 비롯하여 10%, 20%, 30%의 krill meal을 첨가한 급여군을 각각 KM10군, KM20군, KM30군으로 구분하여 4군의 급여군으로 나누어 5주간 실험 사육한 결과는 다음과 같다. 혈청 중 alkaline phosphatase (ALP), aminotransferase (AST, ALT) 및 lactate dehydrogenase(LDH)의 효소 활성은 대조군인 CG군 보다 krill meal을 함량별 첨가 급여군에서 감소되는 것으로 나타났다. 흰쥐의 혈청 및 장기조직(간, 뇌, 심장, 신장)의 불소 함량은 krill meal의 함량에 따라 불소 함량도 증가되는 것으로 나타났다.

The purpose of this study was to probe the influences of krill (Euphausia superba) meal with NaF oral administration on a dose-effect relationship between fluoride levels of krill meal and serum enzyme activity such as alkaline phosphatase (ALP), aspartate aminotransferase (AST), alanine aminotransferase (ALT), and lactate dehydrogenase (LDH) in rats fed experimental diets for 5 weeks. There were no significant decreases in the activities of ALP, AST, ALT, and LDH in sera among krill meal diet groups (KF10, KF20, KF30). However, these groups were significantly (p<0.05) lower enzyme activities than normal diet (ND) plus NaF 10 mg group (NF). The fluoride levels of serum and organ tissues (liver, brain, heart, lung, kidney) in NaF 10 mg groups (NF, KF10, KF20, KF30) were significantly increased by adding krill meal in comparison with normal diet group. The results indicate that a difficult to found toxicity to the tissues from krill meal diet groups.

The aim of the study were to investigate the influences of krill (Euphausia superba) meal on the body weight, lipid metabolism functional improvement, blood glucose level, protein component in the sera of rats which fed experimental diets for 5 weeks. Serum concentrations of total cholesterol, Low-Density Lipoprotein (LDL)-cholesterol, free cholesterol, triglyceride (TG), phospholipid (PL) and blood glucose were higher in the control diet group (G1 group) than the control diet plus 10% krill meal group (G2 group), the control diet plus 20% krill meal group (G3 group), the control diet plus 30% krill meal group (G4 group), and a general dose and time independent one-way analysis of variance was performed to assess efficacy. Conversely depending on the content of krill meal for the High-Density Lipoprotein (HDL)-cholesterol level, it showed higher results. The concentrations of total protein, albumin and globulin in sera, there were not significant difference among the groups (p<0.05). The results indicate that a krill meal diet effectively inhibited increases in lipid elevation, blood glucose level in the sera of rats.

Antarctic krill (Euphausia superba) is typical of a enormous biomass of marine zooplankton that could provide good nutrition in human body. This study was conducted to identify the nutrition of krill, a live in Antarctic Ocean. The analysis result of fatty acids of krill meal was as follow. The compositions of fatty acid were saturated fatty (SFA) acid 41.41%, monounsaturated fatty acid (MUFA) 21.69%, polyunsaturated fatty acid (PUFA) 36.89%, and p/s ratio was 0.89. The major fatty acids in all parts were eicosapentaenoic acid (EPA, 21.54%), palmitic acid (27.51%), oleic acid (13.35%) and docosahexaenoic acid (DHA, 12.42%). Especially, EPA and DHA were occupied 33.96% of polyunsaturated fatty acid. The mineral contents of krill meal were calcium 24477.21 mg kg-1, sodium 14728.69 mg kg-1, magnesium 6973.49 mg kg-1, potassium 3981.67 mg kg-1, iron 395.33 mg kg-1 and manganese 5.74 mg kg-1. The contents of major vitamin were retinol 86717.37 μg RE, β-carotene 44.87 μg RE, tocopherol 2.60 mg, pantothenic acid 1.61 mg, indicating that krill meal contains large amount of retinol and β-carotene.