• Preventive Nutrition and Food Science
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• 제11권2호
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• pp.120-126
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• 2006

Fish backbone, a major by-product in the fish processing industry, accounts for about 15% of whole fish weight. In this study, recovery of bioavailable calcium from Alaska pollack (Theragra chalcogramma) backbone by-products using enzymatic hydrolysis was investigated. Finely ground fish backbones were hydrolyzed with two proteolytic enzymes (pepsin and protease) to obtain soluble calcium from the by-products. The pepsin digest had a higher degradation efficiency (88%) than protease. Four different concentrations of the fish backbone calcium (100, 250, 500 and 1000 mg/L) prepared by the pepsin digest were treated with $Na_2HPO_4$ at a concentration gradient (0, 1, 2, 4, 8, 10, 15 and 20 mM) to evaluate their solubility, revealing that solubilities of the fish backbone calcium were superior to those of $CaCl_2$ at all the calcium and $Na_2HPO_4$ concentrations. Among the tested concentrations the highest solubility was found in the pepsin digest containing a calcium concentration of 1000 mg/L. Thus, hydrolyzing with pepsin is an effective mode of recovering bioavailable calcium from Alaska pollack fish backbones.

• 한국동물학회지
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• 제32권3호
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• pp.281-289
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• 1989

포유동물의 생식주기중 대부분의 여포는 폐쇄되고 극히 일부만 배란된다. 돼지의 폐쇄여포액내에는 다량의 androgen이 존재하며 이들이 폐쇄의 한 요인이라는 결과로 보아 폐쇄여포액내에는 다량의 활성적 testosterone이 존재할 것으로 추론하고 이를 정량하고져 하였다. 사람의 여포액내 progesterone, testosterone, estradiol, androstenedion과 dihydrotestosterone의 농도를 본 연구에서 정립된 섬광면역측정법 및 방사면역측정법으로 측정한 결과는 다음과 같았다. 사람의 폐쇄된 여표액내 T,A.DHT의 농도는 소, 중, 대 여포 공히 정상의 여포액내 이들 스테로이드의 농도보다 현저히 증가되어 있었다. 그러나 소여포의 경우 폐쇄여포액내 A의 농도는 정상에 비하여 현저히 낮은 농도를 나타내었다. 반면 P와 E의 폐쇄여포액내 농도는 정상에 비해 현저히 낮은 농도를 나타내었다. 돼지의 소, 중, 대의 폐쇄여포액내 P의 농도는 정상과 통계적으로 유의한 차이가 없었다. T의 경우 역시 각 각의 크기를 가진 폐쇄여포액에서 정상 여포액 농도보다 높게 나타났으나 통계적인 유의성은 없었다. 그러나 E의 경우는 폐쇄여포액내 농도가 정상에 비해 편저히 낮게 나타났다. 한편 여포액내 활성적 T의 점유율은 혈청에 비해 현저히 높았다. 즉 bioavailable T는 정상과 폐쇄여포액내에서 각기 90% 이상을 나타내었다. 위의 결과를 종합해 볼 때 동물중, 크기에 따라 폐쇄의 요인은 다른 것으로 사료되며 폐쇄여포액내 활성적 androgen의 농도는 정상에 비해 높고 또한 E의 농도는 현저히 낮은 것으로 나타났다. 또한 여포액내 대부분의 스테로이드는 활성형의 상태로 존재하며 활성적 T는 폐쇄여포의 판정에 주요기준이 될 수 있을 것으로 판단된다.

• 한국토양비료학회지
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• 제49권1호
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• pp.75-80
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• 2016

This study was conducted to evaluate effect of chemical amendments on reducing bioavailable fraction of heavy metals in soil along with ecotoxicological effect on earthworms, Eisenia fetida. Three different chemical amendments, lime (L), steel slag (SS), and acid mine drainage sludge (AMDS), were applied with varied application ratio (1, 3, 5%). Heavy metal contaminated soil was mixed with chemical amedments and earthworms, Eisenia fetida, were cultivated for 28 days. Bioavailable fraction of heavy metals (Cd, Cu, Pb, and Zn) extracted with 0.1N HCl was monitored and also, mortality, growth, and metal concentration in earthworm were assessed. Result showed that all three amendments had high efficiency to reduce bioavailable fraction of heavy metals in soil. In particular, lime showed the highest reduction rate of Cu (63.9-87.7%), Pb (7.90-24.65%), and Zn (40.83-77.60%) among three amendments. No mortality of earthworm was observed during experimental period except 3% and 5% AMDS treatment indicating that application of chemical amendments is safe in terms of ecotoxicological aspect. However, no positive correlation was observed between reduction of bioavaialble fraction of heavy metals in soil and earthworms. Overall, application of chemical amendments in agricultural field can be adapted for reducing bioavailable fraction of heavy metals and detoxification in soil.

• 생태와환경
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• 제41권1호
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• pp.66-72
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• 2008

대도시의 기본 생활수준 향상을 위해 건립된 인공호는 지역적 환경요인에 의한 퇴적물 중금속 오염이 우려된다. 본 연구의 퇴적물 조사대상인 도심의 소형인공호들은 저수용량이 적고, 체류시간이 길며, 도시대기오염으로 인한 침적물낙하와 함께 호수에 유입될 수 있는 중금속이 최종적으로 퇴적물에 축적된다. 본 연구에서는 도시지역에 조성된 인공호를 대상으로 퇴적물매체에 축적된 총중금속, 용존중금속, 그리고 생물이용성 중금속의 상호연관성을 규명하고자 시도하였다. 생물이용량은 약전해질추출법(Weak-Electrolyte Extraction, WEE)에 의해 측정하였다. 도심인공호 전체 조사지역에 대한 퇴적물의 총중금속 검출빈도는 아연, 구리, 크롬, 니켈, 비소, 카드뮴 순으로 확인되었고, 총량에 대한 검출은 아연이 가장 높은 수치를 나타내었다. 총중금속에 대한 생물이용성 중금속의 비율은 중금속별, 측정지역별로 매우 상이하였으며 전반적으로 중금속의 생물이용성은 구리 (Cu)가 높은 것으로 나타났다. 높은 생물이용성을 나타낸 구리의 경우 기존독성연구 결과와 비교한 결과 높은 생태독성을 나타내고 있어 본 연구에서 예측한 현상을 지지하고 있으나, 차후 생물검정법(Bioassay)을 통한 검증이 필요할 것으로 사료된다.

• 동아시아식생활학회지
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• 제16권1호
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• pp.93-98
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• 2006

This study examined whether or not the iron that is accumulated in the recombinant microbes that produce ferritin is bioavailable to rats with iron deficiency. Rats induced with iron deficiency were treated with iron preparations of $Fe(NH_4)_2(SO_4)_2$, horse spleen ferritin, control yeast, and ferritin-producing recombinant yeast for 14 days. The bioavailability of iron was examined by measuring hemoglobin concentration, hematocrit value, and tissue iron stores. Differences between dietary groups were determined by one-way ANOVA, at the level of significance p<0.05. Based on hemoglobin concentration and hematocrit value, iron in $Fe(NH_4)_2(SO_4)_2$, horse spleen ferritin, and ferritin-producing yeast were bioavailable in rats and cured iron deficiency. The efficacy of ferritin and ferritin-producing yeast was confirmed in establishing tissue iron stores after the induction of iron deficiency. The iron sources of ferritin and the ferritin-producing yeast seemed to be as effective for the recovery from iron deficiency as the iron compounds of ferric citrate and ferrous ammonium sulfate. The results suggest that the iron stored in ferritin of the recombinant yeast is bioavailable, and that the recombinant yeast may contribute widely as a source of iron to resolve the global problem of iron deficiency.

• Journal of the korean society of oceanography
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• 제39권4호
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• pp.243-250
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• 2004

Sediment microcosm experiments were conducted for 14 and 28 days using Zn spiked sediment to examine the changing distribution of bioavailab1e sediment-bound Zn at different SEM (simultaneously extracted metal)-Zn/ AVS (acid volatile sulfide) mole ratios as a function of time and amphipod density. In surficial sediments (0-1cm), AVS concentrations significantly decreased due to bioturbation and oxidation, while SEM-Zn concentrations remained unchanged. As a result, SEM-Zn/AVS ratios in the surface sediment were greater one although the ratios were designed as less than one initially. With increasing SEM-Zn/AVS ratios in surficial sediments, concentrations of potentially bioavailable $MgCl_2$extractable-Zn, NaOAc extractable-Zn and pore water-Zn significantly increased, while concentrations of SEM-Zn were not significantly varied. Results suggested that as AVS concentrations decreased, AVS bound Zn was partitioned to other sediment fractions (i.e. $MgCl_2$ and NaOAc extractable) and the pore water, resulting in changes in Zn bioavailability in surficial sediments. Concentrations of AVS, SEM-Zn and pore water-Zn remained unchanged in the deeper layers (>1 cm) of the sediment.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 1998년도 공동 심포지엄 및 추계학술발표회
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• pp.137-141
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• 1998

A chemical has been aging in soil environment is more less bioavailable than freshly added chemical. The amount of bioavailability of the aged chemical is different by bacterial strains. The difference could be depend on physiochemical properties of each strain. Phenanthrene was employed as an aged chemical. Seven bacteria were isolated from activated sludge and petroleum disposed soil. These strains were able to degrade phenanthrene and to grow using phenanthrene as a sole carbon source. According to the result of materialization and chemical extraction experiment, the bioavailable amount of aged phenanthrene which has been aged in Lima loam is different by each bacteria. Several physiochemical properties of each strain were tested to certify correlation with their different amount of bioavailability.

• Asian-Australasian Journal of Animal Sciences
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• 제14권11호
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• pp.1645-1646
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• 2001

The objective of this study was to develop an in vitro digestion technique to estimate bioavailable energy values of different corn hybrids in swine and poultry. A total of 21 samples were investigated; 18 normal corn (NC) and 3 high-oil corn (HOC) hybrids. One step-two enzymes digestion system was introduced to develop the in vitro technique. The gross energy (GE) values of NC hybrids were correlated with the in vitro disappearing energy values (IVE; r=0.85, p<0.01), the in vitro energy digestibilities (IVED; r=0.70, p<0.01), and the in vitro DM digestibilities (IVDM; r=0.55, p<0.05). It appears, however, that IVE values of NC and HOC hybrids were not significantly different according to the one step-two enzyme digestion system. Results of in vivo and in vitro estimates suggested that there was no significant correlation between them in poultry. The IVE value was regressed linearly with ME and DE values in swine with low regression coefficient (34 and 41%, respectively).

• 대한약학회:학술대회논문집
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• 대한약학회 2000년도 춘계총회 및 학술대회
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• pp.98.2-98.2
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• 2000

• 한국해양학회지:바다
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• 제24권2호
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• pp.249-265
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• 2019

수동형채집기(passive sampler)는 해수나 퇴적물 내 공극수에서의 자유용존상 농도 (freely dissolved and bioavailable concentration, $C_{free}$)를 쉽고 보다 정확히 예측할 수 있는 유망한 방법 중 하나이다. 유럽이나 미국에서는 보다 정확한 위해도 평가를 위해 해양환경 모니터링에 수동형채집기를 적극적으로 사용하는 추세이지만, 현장 적용 시 노출시간이 길어짐에 따라 수동형채집기의 생물부착으로 인한 문제점으로 국내에서의 활용도는 매우 낮다. 따라서 본 연구에서는 난분해성 유기오염물질을 대상으로 하는 수동형채집기의 원리 및 기본적인 특징을 파악하고, 수동형채집기의 현장 적용을 위한 다양한 개선 사례를 조사함으로써 국내에서의 수동형채집기의 활용도를 높이기 위한 방안을 제시하였다.