• 상하수도학회지
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• 제17권4호
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• pp.471-478
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• 2003

• Journal of Microbiology and Biotechnology
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• 제9권1호
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• pp.32-38
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• 1999

A biosurfactant produced by Tsukamurella sp. 26A was purified by procedures including acid precipitation, ethylacetate extraction, and adsorption chromatography. The purified biosurfactant reduced the surface tension of water from 72 mN/m to 30 mN/m at a concentration of 250 mg/l, whereas the minimum interfacial tension against n-hexadecane was lowered to 1.5 mN/m at a concentration of 40 mg/i. The compound stabilized oil-in-water emulsions with a variety of commercial oils and had strong emulsification and stabilization activities when compared to those of commercial emulsifiers and stabilizers. Surface tension was stable over a broad range of pH (2-12) and temperature ($100^{\circ}C$, 3h). The biosurfactant was identified as glycolipid having a hydrophilic moiety of trehalose.

• 한국식품영양과학회지
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• 제23권3호
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• pp.496-501
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• 1994

The synthesis of lauryl palmitate from palmitic acid and lauryl alcohol was investigated in organic solvents using lipase. Water-immiscible organic solvent such as hexane, toluenem cyclohexane, and isooctane were found to be suitable of ester synthesis . The effect of water content on the initial rate of conversion was examined . As the content increased, the reaction rate increased. But addition of water in organic solvent decreased therostability of enzyme . The best lauryl palmitate synthesis was achieved with water content of 0.2-0.4% reaction temperature of 4$0^{\circ}C$ and 45$^{\circ}C$ for Candida cylindracea lipase porcine, pancreatic lipase, respectively. when ester synthesis was carried out under the optimum conditions, the conversion yield of palmitate into lauryl palmitate after 70hrs reached 85% and 69 % for the Candida cylindracea lipase and porcine opancreatic lipase, respectivley.

• 한국물환경학회지
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• 제25권1호
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• pp.136-141
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• 2009

Inactivation rates between enterococci and total coliforms were compared in order to find the suitability of enterococci as an indicator microorganism under various experiment conditions - freshwater and/or seawater, indoor and/or outdoor conditions. In case of indoor laboratory experiments, inactivation rates of enterococci ($k_D$: 0.050~0.082) were faster than those of total coliforms ($k_D$: 0.034~0.045) in freshwater matrix. In seawater matrix, however, survival rate of enterococci was longer than that of total coliforms at two out of three experiments in indoor condition. When incubated in outdoor conditions, enterococci were inactivated significantly more rapidly than total coliforms both in freshwater and seawater matrices. With these results, enterococci appear to be less suitable than total coliforms in terms of inactivation rates.

• Journal of Microbiology and Biotechnology
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• 제17권9호
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• pp.1558-1562
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• 2007

To elucidate the influence of pipe materials on the VBNC (viable but nonculturable) state and bacterial numbers in drinking water, biofilm and effluent from stainless steel, galvanized iron, and polyvinyl chloride pipe wafers were analyzed. Although no HPC (heterotrophic plate count) was detected in the chlorinated influent of the model system, a DVC (direct viable count) still existed in the range between 3- and 4-log cells/ml. Significantly high numbers of HPC and DVC were found both in biofilm and in the effluent of the model system. The pipe material, exposure time, and the season were all relevant to the concentrations of VBNC and HPC bacteria detected. These findings indicate the importance of determining the number of VBNC cells and the type of pipe materials to estimate the HPC concentration in water distribution systems and thus the need of determining a DVC in evaluating disinfection efficiency.

• 미생물학회지
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• 제41권2호
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• pp.135-139
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• 2005

Monascus purpureue KCCM 60016으로부터 색소생성 이 우수한 변이주 P-57이 생성한 홍국색소의 항산화 활성을 조사하였다. 홍국색소는 chloroform에 아주 잘 추출되며, 특히 hexane에서는 황색색소가 특이적으로 높게 추출되었다. DPPH radical소거 효과는 hexane분획, chloroform 분획, ethyl acetate분획, butanol 분획, water 분획의 순으로 높게 나타났다. Xanthine oxidase저해효과는 hexane분획, chloroform분획, ethyl acetate 분획의 순으로 높게 나타났으며, hexane 분획물의 경우 5 ppm에서 $41.2\%$, 50 ppm에서 $82.4\%$로 높은 저해율을 보였으며, 저해기작은 비경쟁적 저해였다.

• Journal of Microbiology
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• 제33권3호
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• pp.178-183
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• 1995

The recombinant plasmid of pCU103 constructed by cloning pcbCD genes in pBluescript SK(+) was studied for the effect of temperature on its persistence in different waters by the methods of electrophoresis, Southern hybridization, quantification, and transformation. The plasmid was very rapidly degraded out in non-sterile FW water without regards to water temperature, probably due to the effect of biochemical factor such as nucleases. The pCU103 was most persistent at 4$^{\circ}C$ in any water environments, moderately persistant at 15$^{\circ}C$ but least stable at 3$0^{\circ}C$ such results could be explained by the facts that hydrogen bonds in double-stranded plasmid DNAs become unstable and that nucleases are activated by increasing temperature. The intact structure of pCU1-3 was generally observed by gel electrophoresis under the conditions which the plasmid should be 2.0 ng/$\mu\textrm{l}$ or higher in concentration and that about 10$^2$ CFU/ml or more transformant cells should be recovered.

• 한국수산과학회지
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• 제21권5호
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• pp.288-291
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• 1988

마비성패류독으로 독화된 진주담치를 시료로 하여 축양 또는 가공방법에 따른 제독실험을 한 결과를 요약하면 다음과 같다. 1. 독화된 진주담치를 순환수조에서 축양하였을 때는 유의할 만한 제독효과는 나타나지 않았으나 유수수조에서 축양한 경우는 5일만에 약 $94\%$가 감소하였다. 2. PSP를 0.1N HCl 용액으로 유출하였을 때가 증류수로 추출하였을 때 보다 그 독성이 약 2-5배 높았다. 3. PSP가 $100\~150{\mu}g/100g$ 정도로 독화된 진주담치를 수도수에서 30분간 자숙하였을 때 그 독성은 동물실험결과 검출되지 않았다. 4. PSP가 $175{\mu}g/100g$ of digestive gland인 진주담치를 $116^{\circ}C$에서 65분간 가압살균하였을 때는 동물 실험결과 독성이 검출되지 않았으나 독소함양이 $9539{\mu}g/100g$ of digestive gland인 고독력의 진주담치는 같은 조건에서 가압살균하여도 $171{\mu}g$의 독력이 잔존하였다.

• 한국수산과학회지
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• 제21권5호
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• pp.297-302
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• 1988

마비성패류독으로 독화된 진주담치를 시료로 하여 축양 또는 가공방법에 따른 제독실험을 한 결과를 요약하면 다음과 같다. 1. 독화된 진주담치를 순환수조에서 축양하였을 때는 유의할 만한 제독효과는 나타나지 않았으나 유수수조에서 축양한 경우는 5일만에 약 $94\%$가 감소하였다. 2. PSP를 0.1N HCl 용액으로 유출하였을 때가 증류수로 추출하였을 때 보다 그 독성이 약 2-5배 높았다. 3. PSP가 $100\~150{\mu}g/100g$ 정도로 독화된 진주담치를 수도수에서 30분간 자숙하였을 때 그 독성은 동물실험결과 검출되지 않았다. 4. PSP가 $175{\mu}g/100g$ of digestive gland인 진주담치를 $116^{\circ}C$에서 65분간 가압살균하였을 때는 동물 실험결과 독성이 검출되지 않았으나 독소함양이 $9539{\mu}g/100g$ of digestive gland인 고독력의 진주담치는 같은 조건에서 가압살균하여도 $171{\mu}g$의 독력이 잔존하였다.

• 한국미생물·생명공학회지
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• 제51권3호
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• pp.268-279
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• 2023

The pharmaceutical industry in Bangladesh produces a diverse range of antibiotics for human and animal use, however, waste disposal management is inadequate. This results in substantial quantities of antibiotics being discharged into water bodies, which provide suitable environment for the growth of antibiotic-resistant bacteria, capable of spreading resistance genes. This study intended for exploring the bacterial antibiotic resistance profile in adjoining aquatic environmental sources of pharmaceutical manufacturing facilities in Bangladesh. Seven surface water samples were collected from the vicinity of two pharmaceutical industries located in the Savar area and 51 Escherichia coli isolates were identified using both phenotypic and genotypic methods. Antibiotic susceptibility tests revealed the highest percentage of resistance against ampicillin, azithromycin, and nalidixic acid (100%) and the lowest resistance against meropenem (1.96%) out of sixteen different antibiotics tested. 100% of the study E. coli isolates were observed with Multidrug resistance phenotypes, with the Multiple Antibiotic Resistance (MAR) value ranging from 0.6-1.0. Furthermore, 69% of the isolates were Extended Spectrum Beta-Lactamases (ESBL) positive as per the Double Disk Diffusion Synergy Test (DDST). ESBL resistance genes bla_TEM, bla_CTX-M-13, bla_CTX-M-15, and bla_SHV were detected in 70.6% (n = 36), 60.8% (n = 32), 54.9% (n = 28), and 1.96% (n = 1) of the isolates, respectively, by Polymerase Chain Reaction (PCR). Additionally, 15.68% (n = 8) of the isolates were positive for E. coli specific virulence genes in PCR. These findings suggest that pharmaceutical wastewater, if not properly treated, could be a formidable source of antibiotic resistance spread in the surrounding aquatic environment. Therefore, continued surveillance for drug resistance among bacterial populations around drug manufacturing facilities in Bangladesh is necessary, along with proper waste disposal management.