• Asian-Australasian Journal of Animal Sciences
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• 제14권3호
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• pp.351-357
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• 2001

The rapid formation of a cream line cannot be observed in raw goat's milk standing at a low temperature. Although the poor creaming ability of goat's milk has been considered to be due to the small size of milk fat globules and the lack of euglobulin capable of being adsorbed on milk fat globules, there is much left to study. The present work attempted to elucidate a factor for poor creaming ability of goat's milk. The creaming ability of the experimental milks reconstituted from creams and skim milks separated from cow's milk or goat's milk was measured by the volume of the cream layer and the fat content of bottom layer. The polypeptides composition of the P1 the fraction (i.e., the high molecular weight fraction eluted near the void volume obtained by the gel filtration of whey) and milk fat globule membrane prepared from both milks were compared. It was found that the promotion of creaming originated from goat's skim milk was lower than that from cow's skim milk. The P1 fraction in goat's skim milk was less than that in cow's skim milk. The polypeptide (M.W. $4.3{\times}10^4$), found in the P1 fraction of cow's milk was not found in the P1 fraction of goat's milk. It is suggested that the poor creaming ability of goat milk is caused mainly by the difference from cow milk in the amount and the composition of the P1 fraction.

• 한국식품과학회지
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• 제29권2호
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• pp.337-342
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• 1997

벌꿀발효주인 mead 와 melomel의 제조방법을 비교하기 위하여, 천연벌꿀을 희석하여 제조한 mead와 벌꿀로 삼투압추출법에 의해 얻은 매실쥬스를 희석하여 제조한 매실 melomel의 발효 중 알코올함량, 환원당, 가용성고형분, pH 및 총산도의 변화를 조사하였다. 전반적으로 발효 속도는 mead보다 melomel이 훨씬 빨랐다. 환원당과 가용성 고형분(Brix)은 발효시작 후 16일까지 점차적으로 감소하였으며, 이 기간 동안에 알코올함량은 점차적으로 증가하였다. mead의 경우는 초기 5일까지는 환원 당량의 감소속도와 알코올 생성속도가 다소 지연되는 양상을 나타냈다. 발효 21일 후에는 mead의 알코올함량은 7.6%에 이르렀으며, 매실 melomel은 12.4%에 도달하였다. pH와 총산도는 발효 초기의 변화 외에는 전 발효기간 중 큰 변화를 보이지 않았다. 발효가 끝난 mead와 매실 melomel은 미세여과를 통하여 광투과도가 99.4%인 밝고 투명한 제품을 얻을 수 있었다. 결론적으로 벌꿀을 사용하여 삼투압법으로 추출한 과실을 사용하여 벌꿀발효주를 만드는 melomel의 제조법이 단순히 벌꿀만을 사용하는 mead의 제조법에 비해 장점을 갖음을 알 수 있었다.

• 대한세포병리학회지
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• 제15권1호
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• pp.33-39
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• 2004

We compared the diagnostic accuracy of liquid-based cervicovaginal cytology using $MonoPrep2^{TM}$ system (Monogen, Herndon, Virginia, USA), a manual system based on membrane filtration method, with conventional Pap smear. Study population included 92 patients visiting the gynecologic department under the suspicion of uterine cervical disease. In thirty of them, surgical biopsy was performed. $MonoPrep2^{TM}$ system provided well-preserved monolayer specimen with good nuclear morphology. However, about 19% of specimens were inadequate to interpret due to low cellularity. The detection rate of abnormal cells more than ASCUS (atypical squamous cells of unknown significance) was 23.9% and higher than 19.4 % of conventional Pap smear. Diagnostic concordance rate with conventional Pap smear was 81%, and severe discordance rate influencing on the management of patient was 7.6 %. Among these seven cases, $MonoPrep2^{TM}$ system was more diagnostic only in four. In comparison with histology, the sensitivity of diagnosis of $MonoPrep2^{TM}$ system was 78.9% and slightly higher than 73.5% of conventional Pap smear. However, the specificity was 81.1% and lower than 90.9% of Pap smear. In conclusion, $MonoPrep2^{TM}$ system provided diagnostic accuracies similar to the conventional Pap smear. The inexpertness of slide preparation and the low cellularity were considered to endow a limitation in more accurate evaluation.

• 미생물학회지
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• 제40권2호
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• pp.127-132
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• 2004

활성 오니법에 의한 하수처리장 포기조에서 슬러지를 채취하여 황화물계 악취제거 균주인 Thiobacillus속의 선별 배지로 50개 균주를 분리하였다. 분리한 50개 균주의 동정 결과 7개 균주는 Thiobaecillus neapolitanus, 4개 균주는 Thiobacillus tepidarius, 5개 균주는 Thiobacillus denitrificans, 23개 균주는 Thiobacillus versutus, 2개 균주는 Thiobacillus intetmedius, 9개 균주는 Thiobacillus perometabolis로 동정되었다. 분리 동정한 균주들로 고효율 황화물계 악취(황화수소, dimethyl sulfide, methyl disulfide)제거 균주 스크린을 하였다. 그 결과 황화수소, dimethyl sulfide에 대하여 KT5l(Thiobacillus versutus)균주가 각각 l00％, 85％로 가장 높은 제거율을 보였다. Dimethyl disulfide의 경우에는 전체 균주가 다른 악취성분에 비해 제거율이 낮았는데 KT8l균주가 26％로 가장 높은 제거율을 보였다. 스크린 결과 KT5l균주를 선별하였으며, 선별된 KT51균주를 밀폐된 모형 생물학적 처리 반응기에 적용하여 황 화합물의 제거 효율을 비교한 결과, 황화수소의 경우, 100 ppm을 주입 후 균주 적용전의 운전 결과는 30분 이후에 0.02 ppm 미만(99.8％)으로 제거한 반면, 균주 적용 시의 운전 결과는 15분에 황화수소를 0.02 ppm 미만(99.8％)으로 처리하였다.

• BMB Reports
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• 제34권3호
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• pp.219-224
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• 2001

To identify the antioxidative peptides in the gelatin hydrolysate of bovine skin, the gelatin was hydrolyzed with serial digestions in the order of Alcalase, pronase E, and collagenase using a three-step recycling membrane reactor. The second enzymatic hydrolysate (hydrolyzed with pronase E) was composed of peptides ranging from 1.5 to 4.5 kDa, and showed the highest antioxidative activity, as determined by the thiobarbituric acid method. Three different peptides were purified from the second hydrolysate using consecutive chromatographic methods. This included gel filtration on a Sephadex G-25 column, ion-exchange chromatography on a SP-Sephadex C-25 column, and high-performance liquid chromatography on an octadecylsilane chloride column. The isolated peptides were composed of 9 or 10 amino acid residues. They are: Gly-Glu-Hyp-Gly-Pro-Hyp-Gly-Ala-Hyp (PI), Gly-ProHyp-Gly-Pro-Hyp-Gly-Pro-Hyp-Gly (PII), and Gly-ProHyp-Gly-Pro-Hyp-Gly-Pro-Hyp (PIII), as characterized by Edman degradation and fast-atom bombardment mass spectrometry. The antioxidative activities of the purified peptides were measured using the thiobarbituric acid method, and the cell viability with a methylthiazol tetrazolium assay The results showed that PII had potent antioxidative activity on peroxidation of linoleic acid. Moreover, the cell viability of cultured liver cells was significantly enhanced by the addition of the peptide. These results suggest that the purified peptide, PII, from the gelatin hydrolysate of bovine skin is a natural antioxidant, which has potent antioxidative activity.

• 한국염색가공학회:학술대회논문집
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• 한국염색가공학회 2012년도 제46차 학술발표회
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• pp.119-119
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• 2012

섬유염색산업 중 면섬유의 염색과정에서 발생되는 머서라이징 폐액은 폐수처리장의 pH(수소이온농도)를 올리는 주원인이 되고 있어, 높은 pH에 따른 폐수처리 부과금이나 황산을 이용한 폐수 중화에 사용되는 약품비용이 과다하게 소요되고 있으며, 머서라이징공정에 사용되는 약품인 가성소다 비용이 계속 증가하고 있어, 기업의 환경처리비용 및 약품소모비용에 대한 부담이 매우 큰 실정이다. 본 기술은 머서라이징 폐액에 멤브레인 공정에 적용하여 폐가성소다로부터 가성소다를 회수할 뿐만 아니라, 회수된 가성소다를 다시 머서라이징 공정에 재이용할 수 있도록 하여 약품 절감효과 뿐만 아니라 폐수의 발생량과 오염물질의 농도의 획기적인 저감이 가능한 것이다. 본 연구에서는 서로 다른 기공크기를 갖는 막을 적용하여 투과플럭스, 부피회수율, 부유물질 및 유기물 제거율, 가성소다회수율, 파울링지수 등을 고려하여 폐수 특성에 맞는 가장 적합한 막을 선정하고, 각각의 막에 대하여 온도조건, 압력조건, 화학세정 등의 운전변수를 최적화, 고효율 폐알카리 회수 장치의 경제성 및 기술적 타당성 평가를 통한 가성소다 회수공정을 구성하였다.

• 한국분말재료학회지
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• 제16권1호
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• pp.22-27
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• 2009

To improve the filtration efficiency of porous materials used in filters, an extensive specific surface area is required to serve as a site for adsorption of impurities. In this paper, a method for creating a hybridized porous alloy using a powder metallurgical technique to build macropores in an Al-4 wt.% Cu alloy and subsequent surface modification for a microporous surface with a considerably increased specific surface area is suggested. The macropore structure was controlled by granulation, compacting pressure, and sintering; the micropore structure was obtained by a surface modification using a dilute NaOH solution. The specific surface area of surface-modified specimen increased about 10 times compare to as-sintered specimen that comprised of the macropore structure. Also, the surface-modified specimens showed a remarkable increase in micropores larger than 10 nm. Such a hybridized porous structure has potential for application in water and air purification filters, as well as membrane pre-treatment and catalysis.

• 한국수산과학회지
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• 제47권4호
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• pp.370-375
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• 2014

BACE2 is a membrane-bound aspartic protease that is highly homologous with BACE1. While BACE1 processes the amyloid precursor protein (APP) at a key step in generating ${\beta}$-amyloid peptide and presumably causes Alzheimer's disease (AD), BACE2 has not been demonstrated to be involved in APP processing directly, and its physiological functions are unknown. To determine its function and to develop inhibitors from marine sources, we constructed an overexpression vector for producing BACE2. The gene encoding human BACE2 protease was amplified using the polymerase chain reaction and cloned into the pET11a expression vector, resulting in pET11a/BACE2. Recombinant BACE2 protease was overexpressed successfully in E. coli as inclusion bodies, refolded using the rapid-dilution method, and purified via two-step fast protein liquid chromatography using Sephacryl S-300 gel filtration and Resource-Q column chromatography. The BACE2 protease produced was an active form. This study provides an efficient method not only for studying the basic properties of BACE2, but also for developing inhibitors from natural marine sources.

• 한국물환경학회지
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• 제21권5호
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• pp.464-469
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• 2005

In the nonwoven fabric filter bioreactor (NFBR), both the construction and the operation costs could be saved because a high concentration of microorganism can be maintained in the reactor as in the membrane bioreactor. However, the NFBR process has been investigated only under aerobic and/or anoxic conditions, In this research, a basic anaerobic treatment experiment was performed at $35^{\circ}C$ by feeding an airtight NFBR with a concentrated synthetic organic wastewater. The organic loading rate (OLR) of the NFBR was increased stepwise from $0.25kg\;COD/m^3-day$ to $0.77kg\;COD/m^3-day$ by gradually decreasing the hydraulic retention time from 20 days to 13 days. The results of the research showed that the best COD removal efficiency achieved at the OLR of $0.67kg\;COD/m^3-day$ with a value of 99.3%. The methane content of the produced gas was highest with a value of 61.2% at the OLR of $0.33g\;COD/m^3-day$. The highest methane production rate was $0.89g\;COD/m^3-day$ at the same OLR. The operation was terminated at the OLR of $0.77kg\;COD/m^3-day$ because of the deterioration in COD removal efficiency, gas production rate, and the methane content of the gas. Further researches are recommended for the NFBR to be employed for anaerobic treatment of organic wastewaters.

• 청정기술
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• 제23권1호
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• pp.1-14
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• 2017

높은 농도의 질산염을 포함하는 물은 인간의 건강을 위협하고 부영양화의 원인이 되기 때문에 제한 농도 이하로 처리되어야 한다. 그러나 질산염은 수용액에서의 높은 용해도로 인해 응집, 여과 및 침전과 같은 일반적인 처리공정으로는 제거가 거의 불가능하다. 따라서 흡착, 이온교환, 역삼투, 탈질과 전기투석과 같은 다른 기술이 질산염의 효과적인 제거를 위해 요구된다. 이들 각 기술은 비용, 수질 개선 정도, 잔류물 처리와 전처리 요구와 같은 인자의 비중에 따라 장점과 단점과 가능성을 가지고 있다. 흡착은 가격 효율성, 운전의 용이성과 설계의 간편성으로 가장 보편적으로 사용되는 공정이다. 흡착제의 표면개질은 질산이온 흡착능력을 개선하였다. 역전 전기투석과 역삼투의 질산-선택 멤브레인 공정은 수용액 중의 질산이온 제거에 오랜 동안 많은 지역에서 효과적임이 증명되었다. 두 기술은 높은 농도의 폐기물을 생성하고 이것의 신중한 처분이 필요하다.