• Environmental Engineering Research
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• 제22권2호
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• pp.186-192
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• 2017

The carbon paste electrode (CPE) was modified with the pristine bentonite and hybrid material (HDTMA-modified bentonite). The modified-CPEs are then employed as working electrode in an electrochemical detection of As(V) from aqueous solutions using the cyclic voltammetric measurements. Cyclic voltammograms revealed that As(V) showed reversible behavior onto the working electrode. The hybrid material-modified carbon paste electrode showed significantly enhanced electrochemical signal which was then utilized in the low level detection of As(V). Moreover, the studies were conducted at neutral pH conditions. The electrochemical studies were conducted with scan rates (20 to 200 mV/s) to deduce the mechanism of redox processes involved at the electrode surface. The anodic current was linearly increased, increasing the concentration of As(V) from 5.0 to $35.0{\mu}g/g$ using the hybrid material-modified electrode. This provided fairly a good calibration line for As(V) detection. The presence of varied concentrations of As(III) in the determination of total arsenic was studied. The influence of several cations and anions viz., Cu(II), Mn(II), Zn(II), Pb(II), Cd(II), Fe(III), $Cl^-$, $NO_3{^-}$, $PO_4{^{3-}}$, EDTA and glycine in the detection of As(V) from aqueous solution was also studied. Further, in an attempt to simulate the real matrix analysis, the tap water sample was spiked with As(V) and subjected for As(V) detection using the modified-CPE.

• 한국수산과학회지
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• 제44권6호
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• pp.759-771
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• 2011

We evaluated the pollution levels of organic matter and metallic element (Fe, Cu, Pb, Zn, Cd, Ni, Cr, Mn, As, and Hg) in the intertidal surface sediments of Aphae Island using several sediment quality guidelines (SQGs) and assessment techniques for sediment pollution. Based on the textural composition of sediment, the surface sediments were classified into two main sedimentary facies: slightly gravelly mud and silt. The concentrations of chemical oxygen demand (COD) and acid volatile sulfide (AVS) in the sediments ranged from 4.6-9.9 (mean $7.4{\pm}1.1$) $mgO_2/g{\cdot}dry$ and from ND-0.53 (mean $0.04{\pm}0.10$) mgS/$g{\cdot}dry$, respectively. These values were considerably lower than those reported from a farming area in a semi-enclosed bay of Korea and for SQGs in Japan. The metallic element concentrations in the sediments varied widely with the mean grain size and organic matter content, implying that the concentrations of metallic elements are influenced mainly by secondary factors, such as bioturbation, the resuspension of sediment, and anthropogenic input. The overall results for the comparison with SQGs, enrichment factor (EF), and geoaccumulation index ($I_{geo}$) indicate that the surface sediments are slightly polluted by Cr and Ni, and moderately polluted by As. Our results suggest that the intertidal surface sediments of Aphae Island are not polluted by organic matter or metallic elements and the benthic conditions are suitable for healthy organisms.

• 한국환경보건학회지
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• 제10권2호
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• pp.41-51
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• 1984

This study was performed using samples collected at Myungryundong and at Reservoirs. The purpose of this study was to investigate the differences of water quality between tap and raw water, and to analyse drinking water quality by Fe, Zn from corroded galvanized steel pipe. Results were as follows 1. The older the pipe was, the higher the concentration of Ferrum and Zinc was (t-test : p<0.05). Ferrum and Zinc also exceeded the limits in the older galvanized steel pipe. I think that this comes from the corrosion of pipe. 2. Mercury, Arsenic, Cadmium, Lead, Chomium, Argentum and Aurum not detected in raw water were not detected in tap water. Cobalt, Bismuth and Molybudenum detected in raw water were not detected in tap water. I think that this comes from the quality of raw water, the result of water treatment and the improbability of detection of above metals in water delivery system. 3. Silicon measured 2.4698ppm in raw water, but it ranged from 0.4769ppm to 1.982 ppm in tap water. Manganese measured 0.0638ppm in raw water, but it ranged from 0.0026ppm to 0.0198ppm in 17cases(31%) out of 55samples in tap water. I think that this comes from the water treatment. 4. Aluminium not detected in raw water was found in 17 cases (31%) out of the samples (55cases). It may be considered as the use of coagulants $Al_2(SO_4)_3$. $18H_2O$ and PAC (Poly Aluminium Chloride). The concentration of copper in tap water was much higher in 2 cases(3.6%) out of the samples(55) than that of copper in raw water. I think that this may come from the use of ${CuSO}_4$, the preventive of algae growth, and the result of chlorination, but further study must be necoessary to support the proof.

• Preventive Nutrition and Food Science
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• 제18권4호
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• pp.273-279
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• 2013

Protease widely exists in the digestive tract of animals and humans, playing a very important role in protein digestion and absorption. In this study, a high protease-producing strain Planomicrobium sp. L-2 was isolated and identified from the digestive tract of Octopus variabilis. The strain was identified by physiological and biochemical experiments and 16S rDNA sequences analysis. A protease was obtained from the strain Planomicrobium sp. L-2 through ammonium sulfate precipitation, dialysis and enrichment, DEAE-Sephadex A50 anion-exchange chromatography, and Sephadex G-100 gel chromatography. The molecular weight and properties of the protease were characterized, including optimum temperature and pH, thermal stability, protease inhibitions and metal ions. According to our results, the protease from Planomicrobium sp. L-2 strain designated as F1-1 was obtained by three-step separation and purification from crude enzyme. The molecular weight of the protease was 61.4 kDa and its optimum temperature was $40^{\circ}C$. The protease F1-1 showed a broad pH profile for casein hydrolysis between 5.0~11.0. No residual activity was observed after incubation for 40 min at $60^{\circ}C$ and 60 min at $50^{\circ}C$. F1-1 protease was inhibited by $Mn^{2+}$, $Hg^{2+}$, $Pb^{2+}$, $Zn^{2+}$, and $Cu^{2+}$ ions, as well as PMSF, indicating that the protease F1-1 was a serine protease. Additionally, research basis provided by this study could be considered for industrial application of octopus intestinal proteases.

• Journal of Microbiology and Biotechnology
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• 제22권10호
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• pp.1388-1394
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• 2012

A xylanase-producing thermophilic strain, Geobacillus sp. TC-W7, was isolated from a hot spring in Yongtai (Fuzhou, China). Subsequently, the xylanase gene that encoded 407 amino acids was cloned and expressed. The recombinant xylanase was purified by GST affinity chromatography and exhibited maximum activity at $75^{\circ}C$ and a pH of 8.2. The enzyme was active up to $95^{\circ}C$ and showed activity over a wide pH range of 5.2 to 10.2. Additionally, the recombinant xylanase showed high thermostability and pH stability. More than 85% of the enzyme's activity was retained after incubation at $70^{\circ}C$ for 90 min at a pH of 8.2. The activity of the recombinant xylanase was enhanced by treatment with 10 mM enzyme inhibitors (DDT, Tween-20, 2-Me, or TritonX-100) and was inhibited by EDTA or PMSF. Its functionality was stable in the presence of $Li^+$, $Na^+$, and $K^+$, but inhibited by $Hg^{2+}$, $Ni^{2+}$, $Co^{2+}$, $Cu^{2+}$, $Zn^{2+}$, $Pb^{2+}$, $Fe^{3+}$, and $Al^{3+}$. The functionality of the crude xylanase had similar properties to the recombinant xylanase except for when it was treated with $Al^{2+}$ or $Fe^{2+}$. The enzyme might be a promising candidate for various industrial applications such as the biofuel, food, and paper and pulp industries.

• Journal of Nutrition and Health
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• 제54권1호
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• pp.1-9
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• 2021

This review describes the risk factors of the nutrition crisis in coronavirus disease 2019 (COVID-19) infections and suggests precision nutrition against long-term psychological and physiological stress. The mandatory quarantine and the social distancing are associated with an interruption of the lifestyle routine, resulting in psychological (i.e., boredom) and physiological stress. The stress with multiple causes and forms induces over-compensation of energy-dense food, such as sugary comfort food, and is defined as "food craving" because carbohydrates positively affect the psychological stability with serotonin secretion. The consumption of foods that promote an immune response against viral infections (vitamins & minerals; Cu, folate, Fe, Se, Zn, and Vit A, B6, B12, C, and D), reduce inflammatory cytokines (w-3 fatty acids, Vit D, fibers, and Mg), contain antioxidants (beta-carotene, Vit E, C, Se, and phenolics), and sleep-inducing proteins (serotonin, melatonin, and milk products) is essential. In addition, a reduced Vit D deficiency in winter due to less time spent outdoors under quarantine has been reported to be associated with viral infections. The case fatality rate of COVID-19 was significantly dependent on age, sex, race, and underlying health condition. To prevent malnutrition and cachexia in elderly people, weight loss and muscle wasting should be monitored and controlled. Inadequate protein intake, sedentary lifestyle, and inflammation are significant risk factors for sarcopenia. Moreover, relatively high intakes of fat or carbohydrate compared to low protein intake result in abdominal obesity, which is defined as "sarcopenic obesity." Keeping the food-safety guidelines of COVID-19, this study recommends the consumption of fresh and healthy foods and avoiding sugar, fat, salt, alcohol, and commercially frozen foods.

• Journal of Microbiology and Biotechnology
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• 제33권2호
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• pp.195-202
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• 2023

Protease is a widely used enzyme particularly in the detergent industry. In this research, we aimed to isolate alkaline protease-producing bacteria for characterization as a laundry detergent additive. The screening of alkaline protease production was investigated on basal medium agar plus 1% skim milk at pH 11, with incubation at 30℃. The highest alkaline protease-producing bacterium was 6BS15-4 strain, identified as Bacillus gibsonii by 16S rRNA gene sequencing. While the optimum pH was 12.0, the strain was stable at pH range 7.0-12.0 when incubated at 45℃ for 60 min. The alkaline protease produced by B. gibsonii 6BS15-4 using dairy effluent was characterized. The optimum temperature was 60℃ and the enzyme was stable at 55℃ when incubated at pH 11.0 for 60 min. Metal ions K⁺, Mg²⁺, Cu²⁺, Na⁺, and Zn²⁺ exhibited a slightly stimulatory effect on enzyme activity. The enzyme retained over 80% of its activity in the presence of Ca²⁺, Ba²⁺, and Mn²⁺. Thiol reagent and ethylenediaminetetraacetic acid did not inhibit the enzyme activity, whereas phenylmethylsulfonyl fluoride significantly inhibited the protease activity. The alkaline protease from B. gibsonii 6BS15-4 demonstrated efficiency in blood stain removal and could therefore be used as a detergent additive, with potential for various other industrial applications.

• 한국환경농학회지
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• 제5권2호
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• pp.101-105
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• 1986

폐수중(廢水中) cadmium의 제거(除去)를 위한 목적(目的)으로 천연(天然) Zeolite의 이용가능성(利用可能性)을 조사(調査)한 결과(結果)는 다음과 같았다. Freundlich 흡착상수(吸着常數) $\frac{1}{n}$값이 $0.4{\sim}1.1$인 것으로 보아 천연(天然) zeolite는 효과적(效果的)인 흡착제(吸着劑)였다. 용액중(溶液中) cadmium의 농도(濃度)가 증가(增加)할수록 흡착량(吸着量)은 증가(增加)하였으며 포화(飽和)된 각(各) 양(陽) ion의 종류별(種類別) 흡착량(吸着量)은 Ca-<무처리(無處理)$-<H-{\leqq}Al-<Nazeolite$의 순(順)이었다. 또 천연(天然) Zeolite에 의한 cadmium의 흡착반응(吸着反應) 용액중(溶液中) 공존(共存)하는 Cu와 Zu에 의하여 저해(沮害)되었으며, pH $5{\sim}6$의 범위에서 흡착제거솔(吸着除去率)이 가장 좋았다. 흡착(吸着)된 cadmium을 4종(種)의 염용액(鹽溶液)으로 탈착(脫着)시켜본 결과(結果), 농도(濃度)가 높을수록 많은 양의 cadmium이 탈착(脫着)되었으며, 각(各) 염용액(鹽溶液)의 cadmium 탈착정도(脫着程度)는 $Nacl<CaCl_2<AlCl_3<HCl$의 순(順)이었다.

• 생명과학회지
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• 제20권9호
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• pp.1385-1393
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• 2010

국내산 참당귀의 생리활성 물질을 이용한 건강 기능성 식품 또는 화장품 소재 개발을 위한 기초연구의 일환으로 참당귀 뿌리를 3종류의 곰팡이 균주, A. oryzae, A. kawachii 및 M. purpureus 균주로 발효시켜 polyphenolic compounds, flavonoids, minerals, decursin 및 decursinol angelate 함량 분석과 항산화, 환원력 및 tyrosinase 활성을 측정 하였다. 참당귀 뿌리의 decursin과 decursinol angelate의 총 면적에 대한 함량 비율은 각각 44.0 및 27.3% 였으며, 한편 A. oryzae, A. kawachii 및 M. purpureus에 의한 발효 당귀의 decursin 함량 비율은 각각 52.0, 54.4 및 53.7% 였다. 참당귀 뿌리의 polyphenolic compounds 함량은 2.78% 였으나 발효 당귀에서 모두 약간씩 감소하였고, flavonoid 함량은 1.03% 함유되었으나 M. purpureus 발효 당귀에서 1.18%로 약간 증가하였다. 참당귀 뿌리의 미네랄 조성은 K, Mg, Fe, Ca, Na, Mn, Zn 순이였으며, 발효당귀에서 Na은 감소하고 나머지는 모두 증가하였다. 참당귀 뿌리의 항산화 활성 19%에 비해 A. oryzae, A. kawachii 및 M. purpureus 발효 당귀에서 각각 46, 49 및 56%로 모두 2배 이상 증가하였다. Fe- 및 Cu-환원력은 참당귀 뿌리보다 발효 당귀에서 모두 낮아지는 경향을 보였다. Tyrosinase 저해 활성은 당귀 뿌리의 18%에 비해 A. oryzae, A. kawachii 및 M. purpureus 발효 당귀에서 각각 34, 37 및 45%로 발효에 의해 2배 이상 증가하였다. 이상의 실험결과 발효 당귀에서 대표적인 화합물인 decursin과 decursinol angelate 함량이 증가하고, 항산화 활성 및 tyrosinase 저해 활성이 증가됨으로서 이를 활용한 건강기능 제품 개발 가능성이 높아졌으며, 이러한 제품 개발에 필요한 기초 자료를 제공해주는데 유용하게 사용될 것이다.

• 한국산업보건학회지
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• 제17권3호
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• pp.245-253
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• 2007

This research was performed to evaluate the airborne personal concentration of hazardouse materials during the process of ship construction and surveyed from May 23 to June 30, 2007 in Kyungnam West Distirct, Korea. The subject was 94 ship construction workers exposed to welding fume and respirable particulate. The airborne concentrations of those were compared to Permissible Exposure Limit(PEL) from the Ministry of Labor in Korea. The airborne concentration of 23 samples(48.9%) of welding fumes was less than $5mg/m^3$, that of 16 (34.0%) was between 5 and $10mg/m^3$, and that of 8 (17.0%) was greater than $10mg/m^3$. The airborne concentration of 27 (57.4%) of respirable particulate masses was less than $5mg/m^3$ and the othere are greater than $5mg/m^3$. The welding fumes were identified containing the heavy metasl such as Fe, Mn, Zn, Mg, Ca, and Cu. The respirable particulates has similiar tendency with welding fumes in the component of heavy metals. But the concentration of Ca, Cu, Cr, and Ni turned out to be higher in welding fumes. Twenty (42.6%) of the 47 samples of welding fumes were exceeded PEL. In the heavy metals in welding fumes, ten (21.3%) of the 47 samples of Mn were exceeded PEL. Based on the results, the higher airborne hazardous materials were still exposed to wokers in ship construction process. It is suggested that the appropriate engineering control be applied to minimize the exposed cocnetration in ship building processes.