• Applied Biological Chemistry
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• 제38권5호
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• pp.376-381
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• 1995

내열성 alkaline phosphatase의 탐색을 위해 극도호열균중에서 Thermus caldophilus GK24 균주를 선정하였다. 이 균주를 이용하여 basal salts에 sodium glutamate, bactotryptone, glucose 및 yeast extract를 첨가시킨 배지에서 alkaline phosphatase 생산을 검토하였다. 그 결과 sodium glutamate가 alkaline phosphatase 유도에 효과적인 것으로 판명되었다. Alkaline phosphatase 생산을 위한 최적유도용 배지는 basal salts에 0.3% sodium glutamate, 0.2% bactotryptone, 0.5% glucose를 첨가한 것으로 효소활성은 기본배지보다 약 6배, 표준배지 보다는 약 27.5배 증가하였다. T. caldophilus GK24 alkaline phosphatase는 유도효소로 판명되었다. 무기인산 결핍시에 효소가 생산되며, 생육배지에 무기인산을 첨가하면 효소합성에 저해효과가 있었다.

• Korean Chemical Engineering Research
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• 제54권1호
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• pp.135-139
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• 2016

본 연구에서는 무기염을 첨가한 액-액 추출에 의해 식물세포인 바이오매스로부터 파클리탁셀 회수 방법을 획기적으로 개선하고자 하였다. 다양한 무기염(NaCl, KCl, $K_2HPO_4$, $NaH_2PO_4$, $NaH_2PO_4{\cdot}2H_2O$)을 이용하여 추출효율을 조사한 결과, NaCl에서 가장 낮은 분배계수(0.053)로 가장 높은 파클리탁셀 수율(~96%)을 얻을 수 있었다. NaCl을 이용한 액-액 추출에서 최적의 NaCl/용매 비와 메틸렌 클로라이드/메탄올 비는 각각 1%(w/v)와 26%(v/v)이었다. 또한 최적의 NaCl/용매 비와 메틸렌 클로라이드/메탄올 비에서 파클리탁셀 함량에 따른 영향을 조사한 결과, 순수 파클리탁셀 함량 0.066%(w/v)에서 가장 낮은 분배계수(0.053)로 가장 높은 수율(~96%)을 얻을 수 있었다. 기존 액-액 추출의 경우 총 3회의 추출로 파클리탁셀을 95% 정도 회수 가능한 반면 무기염을 이용한 방법의 경우 단 1회 추출로 대부분의 파클리탁셀을 회수(~96%) 가능하였다.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2007년도 학술발표회 논문집
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• pp.46-52
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• 2007

As flue gas desulfurization (FGD) wastewater contains high concentrations of nitrate and is very low in organic carbon, the feasibility of nitrate removal by autotrophic denitrification using Thiobacillus denitrificans was studied. This autotrophic bacteria oxidizes elemental sulfur to sulfate while reducing nitrate to elemental nitrogen gas, thereby eliminating the need for addition of organic compounds such as methanol. Owing to the unusually high concentrations of dissolved salts $(Ca^{2+},\;Mg^{2+},\;Na^+,\;K^+,\;B^+,\;SO_4^{2-},\;Cl^-,\;F^-,)$ in the FGD wastewater, extensive laboratory-scale and pilot-scale tests were carried out in sulfur-limestone reactors (1) to determine the effect of salinity on autotrophic denitrification, (2) to evaluate the use of limestone for pH control and as source of inorganic carbon for microbial growth, and, (3) to find the optimum environmental and operational conditions for autotrophic denitrification of FGD wastewater. The experimental results demonstrated that (1) autotrophic denitrification is not inhibited up to 1.8 mol total dissolved salt content; (2) inorganic carbon and inorganic phosphorus must be present in sufficiently high concentrations; (3) limestone can supply effective buffering capacity and inorganic carbon; (4) the high calcium concentration may interfere with pH control, phosphorus solubility and limestone dissolution, hence requiring pretreatment of the FGD wastewater; and, 5) under optimum conditions, complete autotrophic denitrification of FGD wastewater was obtained in a sulfur-limestone packed bed reactor with a sulfur:limestone volume ratio of 2:1 for volumetric loading rates up to 400g $NO_{3^-}N/m^3.d$. The interesting interactions between autotrophic denitrification, pH, alkalinity, and the unusually high calcium and boron content of the FGD wastewater are highlighted. The engineering significance of the results is discussed.

• 한국균학회지
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• 제48권3호
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• pp.273-284
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• 2020

본 연구에서는C. indica 자실체의 안정적인 대량생산에 기반이 되는 필수적인 균사체 생산을 위한 최적 배양조건을 구명 하고자하였다. C. indica 균사체의 효율적 배양을 위한 조건은 최적 배양 온도 30-32℃, pH 6.0, 탄소원 maltose 2%, 유기질소원 yeast extract 1%, 무기질소원 NaNO₃ 0.1%, 아미노산 asparagine 0.7%, 유기산 acetic acid 0.1%, 무기염류 MnSO₄ 0.7 mM가 최적 배양조건 이었다. 새로이 MYNA로 명명한 C. indica의 최적 배지는 기존의 PDA 배지보다 균사의 생장이 균일하고, PDA 배지의 배양기간과 비교하였을 때 10.5% 단축하는 효과가 있었다. MYNA 배지는 추후 C. indica의 재배에 널리 활용될 수 있을 것으로 판단된다.

• 융복합기술연구소 논문집
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• 제4권2호
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• pp.23-26
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• 2014

As an effective separation method for biomolecules, aqueous two-phase systems based on ionic liquids were suggested. Hydrophobic ionic liquids are more expensive and viscous in spite of their usage in the ionic liquid/water biphasic extraction compared with hydrophilic ionic liquids. In case of aqueous two-phase systems using hydrophilic ionic liquids, they can be diluted in aqueous phase. Experimental results show that aqueous two phase systems can be formed by adding appropriate amount of ionic liquids to aqueous salts solutions. The viscosity of ionic liquid aqueous phase is proportional to the cation chain length in ionic liquids. It is founded that the ionic liquid based aqueous two phase systems are effective for the separation of biomolecules such as acrylic acid.

• Preventive Nutrition and Food Science
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• 제13권4호
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• pp.354-361
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• 2008

A novel bacterium isolated from Cheonggukjang was identified as a glutamate-dependent Bacillus subtilis HA with 98.3% similarity to Bacillus subtilis Z99104. Optimization of poly-$\gamma$-glutamic acid ($\gamma$-PGA) production by modulating fermentation factors including carbon sources, nitrogen sources, inorganic salts and fermentation time was investigated. Optimum culture broth for $\gamma$-PGA production consisted of 3% glutamate, 3% glucose and various salts, resulting in the PGA production of 22.5 g/L by shaking culture for 72 hr at $37^{\circ}C$. Average molecular weight of $\gamma$-PGA was determined to be 1,220 kDa through MALLS analysis. The $\gamma$-PGA solution showed a typical pseudoplastic flow behavior, and a great decrease in consistency below pH 6.0 regardless of the same molecular weight of $\gamma$-PGA. The molecular weights of isolated $\gamma$-PGA were drastically decreased by heat treatment in various acidic conditions, resulting in different hydrolysis of $\gamma$-PGA. The consistency of $\gamma$-PGA solution was greatly decreased with increase heating time in acidic conditions.

• 공업화학
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• 제18권6호
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• pp.630-635
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• 2007

구조중에 1개의 tert-부틸기를 가진 새로운 형태의 키랄살렌 착체를 합성하여 비대칭반응 촉매로서 활용하였다. 알루미늄족의 금속염을 소유한 이량체형의 키랄 살렌 촉매는 에폭사이드의 산소고리를 페놀류로 여는 비대칭반응에서 매우 높은 활성과 선택성을 나타내었다. 또한 무기담체에 고정화된 살렌 착체도 이 반응에 대하여 효과적인 촉매로 사용할 수 있었다. 새로운 키랄 살렌촉매 중에 존재하는 금속염의 종류는 광학선택적 반응에서 중요한 영향을 나타내었다.

• 한국염색가공학회지
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• 제24권4호
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• pp.247-252
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• 2012

The objective of this study was to find an appropriate method and process for protecting the green color in bamboo leaves and subsequent extraction of the green colorants, chlorophyll. Various inorganic salts including cupric sulfate, ferric sulfate, and zinc chloride were employed as green color protectors. Accordingly, the effects of metal salts and treatment conditions on color protection were investigated to find appropriate protector and conditions. And also, the efficacy of bamboo colorants as a natural green dye was evaluated through dyeing and colorfastness tests. Antimicrobial activity of dyed fabrics was measured by shake flask method in terms of bacterial reduction rate using Staphylococcus aureus(ATCC 6538). On the basis of experimental results for stabilizing bamboo leaves colorants, it was confirmed that Cu was the most appropriate metal type considering dye uptake, photostability and light fastness, and its optimum concentration was 0.025%. After the stabilization, the colorants were extracted efficiently at NaOH aqueous solution of 1.00%. It was concluded that bamboo leave has a high potentiality as new resources to produce a natural green dye with antimicrobial functionality.

• 미생물학회지
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• 제29권5호
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• pp.329-338
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• 1991

From July 1985 to December 1986, 28 variables of phycal-chemical factors, bacteria and heterotrophic activity were investigated 17 times at 3 stations in the estuary of Naktong River and the influences of environmental factors to bacterial population and heterotrophic activity were analyzed through multiple regression. The results of multiple regression were as follows. At station 1, total bacteria and heterotrophic bacteria(Z-25) could explain 57% of the variation of maximum uptake velocity for glucose and 54% of turnover time for glucose was explained by total coliform bacteria and MBOD, Sixty four percent of the variation of Kt+SN was accounted for salinity, MBOD-N and inorganic phosphate. Turnover rate for acetate was also accounted for the change of MBOD-P by 56%. At station 2 maximum uptake velocity for glucose depends on MBOD-N by 81%; turnover time on bacteria by 50%; Kt+Sn on avilable nutrient by 61%. More than 50% of maximum uptake velocity and turnover time for glucose were influenced by bacteria and that of Kt+Sn by the change of nutrient in the surface water of station 3. In the bottom water of station 3, the change of maximumuptake velocity, turnover time and Kt+Sn for glucose was controlled by total bacteria and available nutrient, bacteria, the change of nutrient salts respectively. On the whole, more than 50% of maximum uptake velocity and turnover time for glucose could be due to the change in the number of bacetria and the value of Kt+Sn was affected by the change of nutrient salts. Turnover rate for acetate was controlled by available phosphate at station 1 and by bacteria at station 2 and 3, which showed a distinct difference between the environmental factors which govern the rate of glucose and acetate uptake in the Naktong esturine ecosystem. And bacterial communities were controlled by available nutrients at station 1, by nutrient salts and salinity at station 2 and in the surface water of station 3 and by salinity in the bottom water of station 3.

• 한국식품과학회지
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• 제31권5호
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• pp.1211-1215
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• 1999

마늘을 물로 추출할 때 효소분해와 pH, 그리고 유기산, 유기 또는 무기염의 첨가가 추출액의 고형분 수율과 색에 미치는 영향을 조사하였다. 그 결과 상업적다당류 분해효소에 의한 가수분해는 고형분 수율을 $15{\sim}20%$ 증가시켰으나 녹변현상이 더 발생하였고 노란색과 밝기가 감소되었다. 추출시 pH의 조정은 수율에는 큰 영향이 없었지만, $4.4{\sim}5.0$의 범위에서 녹색의 강도가 증가되어 적절치 않았다. 여러가지의 염과 유기산의 첨가 결과, $CaCl_2$와 sodium oxalate, tartaric acid, phosphoric acid가 수율 향상에 효과적이었으며, $K_{4}P_{2}O_{7}$은 수율향상과 녹변방지에 효과가 있었다.