• Advances in environmental research
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• 제2권3호
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• pp.245-260
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• 2013

Biosorption represents a technological innovation as well as a cost effective excellent remediation technology for cleaning up radionuclides from aqueous environment. In the present study, a bacteria strain FB12 with high adsorption rate of uranium ion was isolated from the vicinity of the nuclear power plant. It was tentatively identified as Bacillus sp.FB12 according to the 16S rDNA sequencing. Efforts were made to further improve the adsorption rate and genetic stability by UV irradiation and UV-LiCl cooperative mutagenesis. The improved strain named Bacillus sp.UV32 obtains excellent genetic stability and a high adsorption rate of 95.9%. The adsorption of uranium U (VI) by Bacillus sp.UV32 from aqueous solution was examined as a function of metal ion concentration, cell concentration, adsorption time, pH, temperature, and the presence of some foreign ions. The adsorption process of U (VI) was found to follow the pseudo-second-order kinetic equation. The adsorption isotherm study indicated that it preferably followed the Langmuir adsorption isotherm. The thermodynamic parameters values calculated clearly indicated that the adsorption process was feasible, spontaneous and endothermic in nature. These properties show that Bacillus sp.UV32 has potential application in the removal of uranium (VI) from the radioactive wastewater.

• Journal of Microbiology and Biotechnology
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• 제14권1호
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• pp.29-34
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• 2004

Biosorption technology is recognized as an economically feasible alternative for the removal and/or recovery of metal ions from industrial wastewater sources. However, the structure of biosorbents is quite complex when compared with synthetic ion-exchange resins, which makes it difficult to quantify the ion-binding sites. Accordingly, this report describes a well-defined method to characterize the pK values and numbers of biomass functional groups from potentiometric titration data. When the proposed method was applied to Sargassum polycystum biomass as a model biosorbent, it was found that the biomass contained three types of functional groups. In addition, the carboxyl group (pK=$3.7{\pm}0.09$) was found to be the major binding sites ($2.57{\pm}0.06 mmol/g$) for positively-charged heavy-metal ions.

• 대한환경공학회지
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• 제22권12호
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• pp.2163-2173
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• 2000

메탄자화균에 의한 코발트 제거의 최적 pH 영역은 6.0~12.0이었으나 메탄자화균을 넣지 않은 blank는 10.5~11.5이었다. 코발트의 제거능은 pH에 크게 의존하였으나 blank보다는 민감하지 않았다. 초기 pH 6.0에서 1.0 g/L의 메탄자화균을 투입했을 때 170 mg Co/g biomass가 제거되었다. SEM 분석 결과에 의하면 코발트는 메탄자확균의 표면이나 세포의 분비 고분자에 흡착되어 제거된 것으로 사료된다. 초기 pH 6.0, 400 mg Co/L에서 메탄자화균의 최적의 투입량은 1.0 g/L이었다. 2.0 M NaCl과 $NaNO_3$의 높은 이온강도 하에서도 코발트 제거능은 그다지 영향을 받지 않았다.

• 한국환경과학회지
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• 제4권5호
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• pp.141-141
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• 1995

The waste biomass of Sacchromyces uvarum, used in fermentation industries to produce ethanol, were studied for their ability to absorb various heavy metal ions. Heavy metal ions studied in this research were Cd, Co, Cr, Cu, Ni and Pb. The order of the sorption capacity was Pb>Cu>Co=Cr=Cd>Ni. The living Sacchromyces uvarum exhibited higher metal-uptake capacity than the dead Sacchromyces uvarum. After we compare the uptake capacity of the Sacchromyces uvarum for individual metal ions with for a mixture of them, the following was observed: in the mixed heavy metal solution the uptake capacity was decreased than the one heavy metal solution. The selective uptake was observed when all . the heavy metal ions were dissolved in a mixed solution. The adsorption isotherm modelling was decribed with the Langmuir and Freundlich model. The results were in good agreement with the Langmuir model.

• 한국축산식품학회지
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• 제42권1호
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• pp.34-45
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• 2022

Spirulina platensis was included at 2.5%, 5%, and 7.5% of the diet as a phytobiotic either as a crude preparation or after enrichment by a biosorption process and fed to 126 Japanese quail and the eggs collected and examined for 6 weeks. Assessments were made of physical and chemical characteristics of the eggs. All treatments with added Spirulina increased unsaturated fatty acids and decreased saturated fatty acids with the largest responses for linolenic (omega 3) and oleic (omega 9) acids. The changes in fatty acids were greater with enriched than crude Spirulina. These results suggest that eggs from quail fed with Spirulina may have positive effects on human health.

• 대한환경공학회지
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• 제28권7호
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• pp.738-745
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• 2006

본 연구에서는 염색폐수의 색도제거 기전을 미생물 floc에의 물리 화학적 흡착과 미생물의 대사에 의한 생물학적 제거의 두 가지로 분류하였다. 색도제거의 반응 조건, 즉 혐기/호기 조건, cosubstrate의 종류와 주입량 등을 회분식 실험에 의해 규명하고, 활성슬러지와 비활성슬러지의 biosorption 실험을 통하여 색도제거 기전을 확인하였다. 염색폐수의 색도는 호기조건과 혐기조건에서 각각 102 ${\Delta}$unit/g MLSS, 123 ${\Delta}$unit/g MLSS가 제거되어 혐기조건에서의 제거율이 높았으며, 유기물은 호기조건에서 82 $mg{\Delta}$COD/gMLSS, 혐기조건에서 75 $mg{\Delta}$COD/gMLSS 제거되어 호기조건에서 제거율이 더 높게 나타났다. Cosubstrate로서 실폐수인 가정하수와 acetate를 이용하여 주입량에 따른 염색폐수의 제거능을 분석한 결과, cosubsrate의 주입에 따라 색도 및 유기물 제거량이 증가함을 확인하였으며 가정하수보다는 acetate가 색도제거에 있어서 더 효율적인 cosubstrate임을 알 수 있었다. 활성슬러지와 멸균된 비활성슬러지를 이용한 색도제거 실험 결과. 비활성슬러지의 색도제거량은 가정하수의 주입에 따라 $20.3{\sim}37.3$ ${\Delta}$unit/g MLSS, 활성슬러지는 $102.0{\sim}159.0$ ${\Delta}$unit/g MLSS로 나타났다. 또한 반응 초기에는 물리 화학적 흡착이 우세하였으나 시간이 지나면서 생물대사 작용에 의한 제거가 증가하는 경향을 보였으며, cosubstrate의 주입에 따른 미생물의 대사에 의한 제거분율이 증가하는 것으로 분석되었고, 이는 호흡율 측정결과와도 그 경향이 일치하였다.

• Korean Chemical Engineering Research
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• 제58권2호
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• pp.301-306
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• 2020

We investigated the individual biosorption removal of lead, copper, and nickel ions from aqueous solutions using Chara sp. algae powder in a batch mode. The impact of several parameters, such as initial concentration of the metal ions, contacting time, sorbent dose, and pH on the removal efficiency, was investigated. The maximum removal efficiency at optimum conditions was found to be 98% for Pb(II) at pH = 4, 90% for Cu(II) at pH = 5, and 80% for Ni(II) at pH = 5. The isotherm study was done under the optimum conditions for each metal by applying the experimental results onto the well-known Freundlich and Langmuir models. The results show that the Langmuir is better in describing the isotherm adsorption of Pb(II) and Ni(II), while the Freundlich is a better fit in the case of Cu(II). Similarly, a kinetic study was performed by using the pseudo-first and second-order equations. Our results show that the pseudo-second-order is better in representing the kinetic adsorption of the three metal ions.

• 환경생물
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• 제19권2호
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• pp.93-99
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• 2001

중금속을 처리하는 방법에는 일반적으로 화학적, 물리적 그리고 생물학적 처리방법 등이 있다. 이중 생물학적 처리방법은 미생물들의 자연 생체기작을 이용하는 방법으로, 생체축적 (biosorption & bioaccumulation), 산화환원반응 (oxidation & reduction), 메칠화 및 탈메칠화반응 (methylation & demethylation), 금속 유기물질 복합반응 (metal-organic complexation)과 비용해성 복합체형성 (insoluble complex formation) 등의 기작을 이용한 방법이다. 이런 중금속에 대한 생물학적 기작들은 중금속으로 오염된 환경을 복원시키는 데에 중요한 기술기반을 제공한다. 최근 금속의 종류와 미생물균주의 종류와 조건 그리고 오염환경에 따른 다양한 방법의 중금속 처리들이 제시되었고, 이는 주로 곰팡이, 박테리아, 조류(algae) 등을 이용한 방법들이다. 또한 분자생물학의 발전과 더불어 중금속 제거능력을 배가시킨 균주의 최근 개발시도는 기존의 생물학적 처리방법을 개량 발전시킬 수 있는 가능성을 제시하고 있다.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2005년도 INTERNATIONAL SYMPOSIUM ON SOIL & GROUNDWATER ENVIRONMENT
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• pp.143-144
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• 2005

• Environmental Engineering Research
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• 제20권1호
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• pp.41-50
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• 2015

The cyanobacterium Anabaena doliolum Ind1 isolated from a coal mining site was tested for removal of cadmium at optimum pH 7.0 and temperature $25^{\circ}C$. The organism recorded high percentage of metal removal (92-69%) within seven days of exposure to 0.5-2.0 ppm cadmium. Biosorption onto the cell surface was the primary mode of metal removal. Fourier transform infrared spectroscopy (FTIR) established hydroxyl, amides, carboxyl, sulphate and carbonyl groups to be the major functional groups on the cell surface involved in cadmium binding. Cellular ultrastructure and a range of vital physiological processes (i.e., photosynthetic pigments, respiration, photosynthesis, heterocyst frequency and nitrogenase activity) remained unaffected upon 0.5 ppm treatment; higher concentrations of cadmium exerted visible adverse effects. Amongst the five photosynthetic pigments tested, phycocyanin was the most targeted pigment (inhibition was 15-89%). Both respiration and photosynthetic activities were inhibited by cadmium with more severe effect seen on respiration. 2.0 ppm cadmium exposure also had drastic negative effect on nitrogenase activity (87% decreased).