• 한국지하수토양환경학회지:지하수토양환경
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• 제21권6호
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• pp.56-66
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• 2016

Generally, the contribution of crop-intake pathway (CIP) is remarkable in human health assessment (HHA) of heavy metal contamination. Although the crop exposure concentrations (Cp) should directly be used for calculating the average daily dose (ADD) of CIP, the soil exposure concentration (Cs) multiplied by soil-crop bio-concentration factor (BCF) has frequently been used instead of using Cp values. Thus, the BCF values are significant in the HHA, and care should be taken to ensure the reasonable acquisition of BCF values. Meanwhile, the BCF values are known to be significantly affected by analytical methods. Nevertheless, they have been calculated from the concentrations of soil and crop analyzed by only one method: total digestion (aqua regia extraction). For this reason, this study was initiated to seek appropriate soil analysis methods for effective computation of the ADD of CIP. The concentrations of 5 metal contaminants (As, Cd, Cu, Pb, and Zn) in 127 soil samples obtained from 4 abandoned metal mine areas were analyzed by several methods including total digestion and partial digestions using 0.1/1 N HCl, 1M $NH_4NO_3$, 0.1 M $NaNO_3$, and 0.01M $CaCl_2$. The heavy metal concentrations in 127 crop samples (rice grains) were analyzed by total digestion as well. Using the concentrations of soils and crops, the BCF values of each contaminant were calculated according to the kind of soil extraction methods applied. Finally, the errors between Cp and $C_s{\times}BCF$ were computed to evaluate the relevance of each method. The results indicate that the partial extraction using 0.1 N and 1 N HCl was superior or equivalent to total digestion. In addition, the 0.1M $NaNO_3$ method combined with total digestion is recommended for improving the reliability of BCF values.

• 유기물자원화
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• 제28권3호
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• pp.15-26
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• 2020

하수슬러지 소각재에서 인(P)을 회수하기 위해 소각재를 황산 용액으로 추출한 후, 알칼리 물질로 pH를 높이면서 회수되는 인(P)과 불순물인 중금속 함량을 비교하여 최적의 인(P) 회수 조건을 실험하였으며, 이때 산추출액을 재사용하거나, 소각재를 입자크기 별로 구분하였을 때 인(P) 회수효율을 비교하였다. 하수슬러지 소각재로부터 인(P)을 회수하기 위한 조건은 1N 황산 용액으로 L/S비 10, 추출시간 30분으로 하는 것이 최적이었다. 인(P)을 회수하기 위한 적정 pH는 알칼리 물질 첨가량, 회수되는 침전물 내의 중금속 함량 등을 고려하였을 때 pH 5 이전에 생성되는 침전물에서 인(P)을 회수하는 것이 유리한 것으로 판단된다. 소각재 추출액의 재사용율(100, 50%)에 따라 인(P)의 회수율을 각각 14, 21% 증가시켰으나, Zn 함량이 각각 33, 21%, Cu의 함량이 각각 35, 20% 증가되었다. 하수슬러지 소각재를 입자크기별로 4개 구간으로 나누어 실험한 결과 특정 크기 구간의 소각재 만을 인(P) 추출하는데 따른 장점은 없었다. EDTA와 양이온 교환수지 등을 통한 추출액 중의 중금속 제거 효과는 크지 않았다.

• Journal of Nutrition and Health
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• 제38권1호
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• pp.20-29
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• 2005

This study is conducted to determine the effects of dietary levels of corn and tuna oils on the formation of preneoplastic lesions in die-thylnitrosamine (DEN) induced rat hepatocarcinogenesis. Weanling male Sprague-Dawley rats were fed 2.5, 5, 15, 25% (w/w) corn or tuna oils. Hepatocellular carcinogenesis was induced by DEN (200 mg/kg body weight) and two-thirds partial hepactectomy was carried out 3 weeks later and were sacrificed 8 weeks after DEN initiation. Tuna oil group showed smaller area of placental glutathione S-transferase (GST-P) positive foci than com oil group. Com oil group of 25% (w/w) showed the widest area of GST -P positive foci, and tuna oil group showed significantly smaller area of GST-P positive foci than com oil in 25% (w/w) level but had no differences between oil levels. Thio-barbituric acid reactive substances (TBARS) content was the highest in 25% (w/w) level of tuna oil group fed long chain and highly polyunsaturated fatty acids. Also serum ${\gamma}$ -glutamyltranspeptidase (GGT) activities in 25% level of tuna oil group were significantly higher than by other levels. As oil contents increased, glucose 6-phosphatase (G6Pase) seems to decrease in com oil groups but remained the same in tuna oil groups. Glutathione reductase (GR) activities were significantly higher in tuna oil group, and the higher the level of tuna oil, the higher GR activities. But Cu/Zn superoxide dismutase (SOD) and glutathione peroxidase (GPx) activities didn't seem to be influenced by levels and kind of dietary fats. Therefore, as oil levels increased, com oil rich in n-6 fatty acids promoted carcinogenesis but tuna oil rich in eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) of n-3 fatty acids suppressed. Although lipid peroxidation products were elevated in 25% (w/w) tuna oil group, GST-P positive foci didn't increase. Therefore pre-neoplastic lesions might be reduced through mediation of a lipid peroxidation process in tuna oil. As fat contents of tuna oil increased, elevated GR activities may give a rise to produce more reduced glutathione in order to protect against free radical attack, and high G6Pase activities remained the same and they contributed to membrane stability. So tuna oil diet seems to protect hepatocarcinogenesis.

• 한국토양환경학회지
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• 제2권3호
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• pp.69-80
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• 1997

오염된 토양을 복원하기 위해서는 주변 환경에 있어서 오염원의 분포 특성과 오염원에 의한 피해 정도를 조사하는 것이 필요하다. 본 조사는 폐금속 광산으로부터 발생된 중금속 오염 현황에 대한 정보를 얻기 위하여 광미와 농경지 토양의 물리화학적 특성을 조사하였으며 광미와 농경지 토양, 그리고 하천 침전물의 시안, 카드뮴, 구리 , 납, 아연, 비소, 크롬, 그리고 수은의 함량을 조사하였다. 농경지 토양과 광미의 pH는 각각 5.4, 8.4이었다. 광미중 시안, 납, 카드뮴, 그리고 비소의 함량은 99.98, 1,752.12, 31.88, 298.50 mg/kg이었다. 이들 중금속의 함량은 공장 산업지역의 대책 기준치보다 높은 함량이었으며 농경지 토양에서 시안과 중금속의 평균량은 광산 주변 비오염지역보다 높았다. 특히, 하천 주변 농경지 토양의 중금속 함량은 다른 주변 농경지보다 높게 나타났다. 광미장 하부 하천의 시안과 중금속의 함량은 광미장의 함량과 비슷하였으나 광미장으로부터 거리에 멀어짐에 따라 하천에 잔존하는 시안과 중금속의 함량은 감소하는 경향을 보였다.

• Journal of Microbiology and Biotechnology
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• 제20권3호
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• pp.518-524
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• 2010

A mannanase gene (man26B) was obtained from a sea bacterium, Paenibacillus sp. BME-14, through the constructed genomic library and inverse PCR. The gene of man26B had an open reading frame of 1,428 bp that encoded a peptide of 475- amino acid residues with a calculated molecular mass of 53 kDa. Man26B possessed two domains, a carbohydrate binding module (CBM) belonging to family 6 and a family 26 catalytic domain (CD) of glycosyl hydrolases, which showed the highest homology to Cel44C of P. polymyxa (60% identity). The optimum pH and temperature for enzymatic activity of Man26B were 4.5 and $60^{\circ}C$, respectively. The activity of Man26B was not affected by $Mg^{2+}$ and $Co^{2+}$, but was inhibited by $Hg^{2+},\;Ca^{2+},\;Cu^{2+},\;Mn^{2+},\;K^+,\;Na^+$, and $\beta$-mercaptoethanol, and slightly enhanced by $Pb^{2+}$ and $Zn^{2+}$. EDTA did not affect the activity of Man26B, which indicates that it does not require divalent ions to function. Man26B showed a high specific activity for LBG and konjac glucomannan, with $K_m,\;V_{max}$, and $k_{cat}$ values of 3.80 mg/ml, 91.70 ${\mu}mol$/min/mg protein, and 77.08/s, respectively, being observed when LBG was the substrate. Furthermore, deletion of the CBM6 domain increased the enzyme stability while enabling it to retain 80% and 60% of its initial activity after treatment at $80^{\circ}C$ and $90^{\circ}C$ for 30 min, respectively. This finding will be useful in industrial applications of Man26B, because of the harsh circumstances associated with such processes.

• 원예과학기술지
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• 제35권3호
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• pp.289-299
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• 2017

The objective of this study was to determine the effect of replacing perlite (PL) with pellets processed with poultry feather fiber as an inert material to prepare growing medium. The growth and flowering of Salvia splendens 'Vista Red' grown in individual growing medium $Biosangto^{(R)}$, peat moss (PM), PL, and two pellets (P45-1 and P45-2) were evaluated. Peat moss was mixed with PL, P45-1, or P45-2 at various ratios (1:0 to 1:3 or 3:1 by volume) to investigate the feasibility of replacing PL with pellets. Nutrient composition of the growing medium and leaf tissues was analyzed. The number of florets, inflorescence length, plant height, and fresh weight of plants grown in media containing P45-1 or P45-2 were reduced compared to those grown in individual growing medium PM or PL. As the mixing ratio of P45-1 or P45-2 to PM was higher, the growth of salvia, such as inflorescence length, plant height, number of leaves, and fresh weight was inhibited. Our results indicate that mixing three parts PM with one part of P45-1 (PM/P45-1/3:1) or P45-2 (PM/P45-2/3:1) accelerated flowering and increased the number of florets and leaves compared to other mixing ratios of PM and pellets media. The concentrations of phosphorus (P), calcium (Ca), boron (B), iron (Fe), and copper (Cu) in individual growing medium PL, P45-1, and P45-2 were significantly lower than those in PM. The concentration of N was the highest in leaves of plants grown in P45-1 or P45-2 amended media, and the concentrations of P, Ca, and zinc (Zn) in leaves were lower in individual growing medium P45-1 or P45-2 than in PM and PL. The pH of PM/P45-1/3:1 or PM/P45-2/3:1 media was maintained at optimal level (5.8-5.9) and the concentrations of macro- and micro-elements in the media and leaves were considered to be optimal levels. Therefore, mixing three parts PM with one part P45-1(PM:P45-1/3:1) or P45-2 (PM:P45-2/3:1) is recommended for improved growth and flowering in salvia. This suggests that P45-1 or P45-2 can replace PL as an inert material to prepare growing medium.

• 한국식품과학회지
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• 제30권1호
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• pp.82-89
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• 1998

새우젓에서 protease를 추출, 정제하여 이의 효소학적 특성을 조사하였다. 새우젓 protease를 추출, 전기투석으로 탈염, ammonium sulfate로 단백질을 분획 시킨 후 Sephadex G-100 column chromatography와 DEAE-cellulose column chromatography를 행하여 정제하였으며 정제 효소는 전기영동상 단일 band로 나타났으며 분자량은 24 kDa, 수율은 14%, 비활성역가는 8.4 unit/mg, 정제배수는 9.8이었다. 정제효소의 최적 pH는 8.0이었고 $pH\;7.0{\sim}10.0$의 범위에서 안정하였다. 단백질 분해 효소 활성의 최적 온도는 $40^{\circ}C$이었고 $30{\sim}60^{\circ}C$의 온도 범위에서 안정성을 나타내었다. 기질에 대한 특이성으로 합성기질인 BAPNA, TAME에는 활성을 보였으며 hammersten casein을 기질로 사용하였을때의 Km값은 $5.1{\times}10^{-7}\;M$이었다. 금속 이온의 영향으로는 $M^{++}$만이 활성이 증가되었고 다른 금속 이온들에 의해서는 저해되었다. 저해제의 효과에서는 STI차 TLCK에 의해 현저하게 저해되었다. 이상의 성질에서 새우젓에서 분리된 protease는 serine계의 trypsin-like enzyme으로 추정되었다.

• 한국지구과학회지
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• 제24권4호
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• pp.290-302
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• 2003

광주광역시의 풍암매립지 주변에 분포하는 하상퇴적물, 주변토양, 침출수의 배수관 내에서 채취한 슬러지 그리고 물(하천수, 침출수, 지하수)의 지구화학적 특성을 연구하였다. 하상퇴적물에서 상류에서 하류 쪽으로 규칙적인 함량변화는 나타나지 않는다. 하상퇴적물에서 가장 풍부하게 산출되는 주원소는 Fe(7.08wt.%)이다. 하상퇴적물 GJ-23, 34는 중금속을 다량으로 포함하고 있지만, 심각한 환경 피해를 일으킬 수 있는 농도는 아니다. 주변 토양 중에서 침출수 저장고와 인접한 토양(GJ-8)에서의 철 함량은 35.1wt.%, 비소 함량은 38.8ppm으로 가장 높다. 침출수구에서 채취한 슬러지 시료 GJ-7의 Cr함량은 .45.6ppm으로 토양오염 우려기준을 훨씬 초과한다. 침출수는 총용존물질(2210, 2470mg/L)과 전기전도도(468, 530ms/cm)가 높고, 양이온에서 Na, K가, 음이온에서 HCO$_3$가 우세하다. 침출수인 PK-3은 Cl함량이 비교적 높아 파이퍼도에서 Na-Cl 영역에 점시된다. 지하수와 하천수는 질산성질소의 함량이 음용수 기준을 훨씬 넘어서 식수로 사용하기에는 부적절한 것으로 나타났다.

• 한국환경보건학회지
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• 제35권6호
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• pp.517-525
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• 2009

The water quality of Lake Shihwa had been rapidly deteriorating since 1994 due to wastewater input from the watersheds, limited water circulation and the lack of a wastewater treatment policy. In 2000, the government decided to open the tidal embankment and make a comprehensive management plan to improve the water quality, especially inflowing stream water around Shihwa and Banwol industrial complex. However, the water quality and microbial community have not as yet been fully evaluated. The purpose of this study is to investigate the influent water quality around the industrial area based on chemical and biological analysis, and collected surface water sample from the Siheung Stream, up-stream to down-stream through the industrial complex, Samples were collected in July 2009. The results show that the downstream site near the industrial complex had higher concentrations of heavy metals (Cu, Mn, Fe, Mg, and Zn) and organic matter than upstream sites. A combination of DGGE (Denaturing Gradient Gel Electrophoresis) gels, lists of K-WQI (Korean Water Quality Index), cluster analysis, MDS (Multi-Dimensional Scaling) and PCA (Principal Component Analysis) has demonstrated clear clustering between Siheung stream 3 and 4 and with a high similarity and detected metal reducing bacteria (Shewanella spp.) and biodegrading bacteria (Acinetobacter spp.). These results suggest that use of both chemical and microbiological marker would be useful to fully evaluate the water quality.

• 한국식품과학회지
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• 제37권4호
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• pp.542-548
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• 2005

대나루(왕대)를 여러 가지 방법으로 추출하고 그 추출액의 화학 성분을 분석하였다. 대나무 추출액의 pH는 5.0-5.5였고, 가용성고형분과 총페놀 함량은 알코올 추출액이 각각 $13.7^{\circ}Brix$와 0.42%로 가장 높았으며, 증발잔사는 직접가열 추출액이 3.8%로 가장 높았다. 무기성분은 K이 가장 높은 함량을 보였으며, 추출방법에 따라서는 간접가열이 가장 높은 무기물 함량을 나타내었다. 중금속은 Al, Cr, Cu, Mn, Ni, Pb, Zn, 등이 검출되었으며, 유해중금속 중 As, Cd, Hg는 검출되지 않았고 Cr, Pb는 극미량 검출되었다. 폴리페놀은 catechin, chlorogenic acid, caffeic acid, 3-hydroxy benzoic acid, ferulic acid등 5종이 확인되었으며 이중 3-hydroxy benzoic acid와 catechin이 주종을 이루는 것으로 나타났다. 유리당은 galactose, glucose, fructose 및 sucrose가 검출되었으며 glucose와 sucrose의 함량이 가장 높았다. 유기산은 citric acid, tartaric acid, malic acid, succinic acid, acetic acid 등이 검출되었으나 직접가열 추출액은 tartaric acid가, 물 추출액과 알코올 추출액은 citric acid, tartaric acid 및 succinic acid가 검출되지 않았다. 항산화 활성은 간접가열 추출액과 알코올 추출액이 상업용 항산화제인 BHA와 ${\delta}-tocopherol$ 보다 우수하였다. 아질산염소거능은 pH 1.2와 3.0에서 효과가 우수하였으나 pH 6.0에서는 급격히 감소하였다. Tyrosinase 저해활성은 물 추출액이 가장 높았으며, SOD 유사활성과 ACE 저해활성은 간접가열 추출액이 가장 높았다. 식품 부패균에 대한 항균활성은 Bacillus subtilis, E. coli O157, Staphylococcus aureus에 대하여 높은 것으로 나타났다.