• 한국물환경학회지
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• 제33권4호
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• pp.409-415
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• 2017

This study aims to evaluate the effect of capping materials on blocking pollutant elution from contaminated sediment to water body. Experiments were carried out under conditions in which the elution rate was intensified artificially using compost with high concentration of organic compound and nutrient salts instead of sediments. Activated carbon (AC), modified activated carbon (MAC), P. putida immobilized activated carbon (PBAC) and effective microorganisms immobilized activated carbon (EBAC) were used as capping materials. Zeolite (ZT) and two kinds of commercially available microorganisms immobilized zeolite products (ZC, ZN) were used for comparison experiment. The elution rate of organic compound, nitrogen and phosphorus were compared with that of control experiment. The experiments were conducted for 56 days. Concentrations of chemical oxygen demand, total nitrogen, and total phosphorus were measured to use the comparison of release rate of organic compound, nitrogen and phosphorus. From the experimental results, AC based materials showed better performance to block the elution of organic compound and nitrogen than ZT based materials. Although ZT based materials were more effective than AC and PBAC to block phosphorus, MAC and EBAC showed the best performance of phosphorus elution blocking among the all candidate materials. In conclusion, EBAC is considered as the most effective capping materials, because organic compound, nitrogen and phosphorus will be degraded continuously by EM in the long term.

• The Plant Pathology Journal
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• 제17권3호
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• pp.174-179
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• 2001

The plant growth-promoting Pseudomonas strains, WR8-3 (Pseudomonas fluorescens), WR9-11 (Pseudomonas sp.) and WR9-16 (P.putida), which induced resistance systematically in watermelon to gummy stem rot were investigated on their induced systemic resistance(ISR)-related characteristics. The pyoverdine production was repressed in the standard succinate medium by increasing the concentration of $\textrm{FeCL}_3$. But the iron-binding ability on chrome azurol S agar media (CAS) was observed only in the strains, WR8-3 and WR9-16. When the two strains were mutated, the resulting iron-binding siderophore-negative mutants, WR8-3m and WR 9-16m, failed to promote the growth of watermelon and to induce resistance. The strains, WR8-3 and WR 9-16, slightly inhibited the growth of Didymella bryoniae at a low concentration of $\textrm{FeCL}_3$ on Kong's medium B, but not to exert control dffect. The strain WR9-11 showed antagonism in the concentration of $\textrm{FeCL}_3$ from 0 to $1,000\mu\textrm{M}$. When the crude lipoplysaccharide of each strain was treated in the rhizosphere of watermelon, mean lesion area was similar to that of the untreated control. The strains, WR9-11 and WR9-16 produced some level of hydrogen cyanide (HCN). Salicylic acid production was not detected in all of the strains.

• Journal of Microbiology and Biotechnology
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• 제12권4호
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• pp.569-575
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• 2002

Two bacterial strains capable of degrading trichloroethylene (TCE), isolated form soils contaminated with various chlorinated alkenes, were identified as Alcaligenes odorous N6 and Nocardia sp. Hl7. In addition, four KCTC strains, including three strains of Pseudomonas putida and one strain of Sphingomonas chlorophenolica, exhibited an ability to degrade toluene. A. odorans N6 and Nocardia sp. H17 degraded 84% of the initial amount of TCE in a basal salts medium (BSM), containing 0.2 mM TCE as the sole source of carbon and energy, in a day. The optimal pH for growth was within a range of 7.0-8.0. A mixed culture of the four toluene-degrading isolates degraded 95% of 0.2 mM TCE with 1.5 mM toluene as an inducer, whereas no TCE was degraded by the same mixture without an inducer. When a mixed culture of all 6 isolates was used, the degradation efficiency of 0.2 mM TCE was 72% without an inducer, in a day, and 82% with toluene as an inducer. In a continuous treatment, 1,000 mg/1 of TCE in an artificial wastewater was completely removed within 18 h when an activated sludge was used along with the microbial mixture, which was 27 h laster than when only an activated sludge was used. Accordingly, it would appear that such a microbial mixture could be effectively applied to the biological treatment of wastewater containing TCE with or without an inducer.

• 상하수도학회지
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• 제35권3호
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• pp.227-235
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• 2021

This study examined the effect of ultraviolet (UV) application on bacterial disinfection in a commercialized humidifier using ultrasonic wave (UW). To accurately examine disinfection kinetics in tap-water condition, tap-water was sterilized using a filter, and then inoculated with pure cultures of E. coli and P. putida with known viable counts. The disinfection kinetic characteristics were experimentally compared when UV alone, UW alone, and UW+UV together were applied in disinfecting the added bacteria in the commercialized humidifier. When UV alone was applied, bacterial disinfection kinetics followed a first-order decay reaction, and showed an approximately 10-time weaker disinfection compared to the typical UV disinfection in water treatment or wastewater treatment. When UW alone was applied, bacterial disinfection kinetics followed a second-order decay reaction with a low disinfection rate constant of 0.0002 min^-1(CFU/mL)^-1. When UV and UW were applied together, however and interestingly, the disinfection rate constant (0.0211 min^-1(CFU/mL)^-1) was approximately 100 times increased than that for the UW alone case. These results revealed that the co-use of UV and UW can provide synergistic effect on bacterial disinfection in a tap-water condition in household humidifiers.

• The Plant Pathology Journal
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• 제38권6호
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• pp.646-655
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• 2022

Pepper mild mottle virus (PMMoV), one of the most prevalent viruses in chili pepper (Capsicum annuum L.) is a non-enveloped, rod-shaped, single-stranded positive-sense RNA virus classified in the genus Tobamovirus. The supernatants of five bacterial cultures (Pseudomonas putida [PP], Bacillus licheniformis [BLI], P. fluorescens [PF], Serratia marcescens [SER], and B. amyloliquifaciens [BA]) were analyzed to find novel antiviral agents to PMMoV in chili pepper. Foliar spraying with supernatants (1:1, v/v) obtained from Luria-Bertani broth cultures of PP, BLI, PF, SER, and BA inhibited PMMoV infection of chili pepper if applied before the PMMoV inoculation. Double-antibody sandwich enzyme-linked immunosorbent assay showed that treatments of five supernatants resulted in 51-66% reductions in PMMoV accumulation in the treated chili pepper. To identify key compounds in supernatants of PP, BLI, PF, SER, and BA, the supernatants were subjected to gas chromatography-mass spectrometry. The 24 different types of compounds were identified from the supernatants of PP, BLI, PF, SER, and BA. The compounds vary from supernatants of one bacterial culture to another which includes simple compounds-alkanes, ketones, alcohols, and an aromatic ring containing compounds. The compounds triggered the inhibitory effect on PMMoV propagation in chili pepper plants. In conclusion, the cultures could be used to further conduct tissue culture and field trial experiments as potential bio-control agents.

• 한국환경농학회지
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• 제16권2호
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• pp.142-148
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• 1997

중금속오염폐수처리에의 미생물 이용 가능성을 검토하기 위하여 중금속에 강한 내성을 지님과 동시에 균체내 중금속 축적능력이 우수한 중금속 내성균을 분리하여 competing ion, 대사저해제 등과 같은 외부 요인에 따른 균체내 중금속 축적변화를 조사한 결과는 다음과 같다. 중금속을 처리한 용액중 양이온인 $Al^{3+}$이온과 음이온인 $CO_3\;^{2-}$ 및 $PO_4\;^{2-}$이온이 competing ion으로 존재할 경우 중금속 내성균의 균체내 중금속 축적은 크게 감소되었으나, 그외 다른 양이온들과 음이온들에 대해서는 거의 영향을 받지 않았다. Cd, Zn 및 Cu 내성균주의 Cd, Zn 및 Cu 축적은 대사저해제에 의하여 크게 감소되었으나, Pb 내성균주에 의한 Pb 축적은 거의 영향을 받지 않는 것으로 나타나 Cd, Zn 및 Cu 내성균주의 Cd, Zn 및 Cu 축적은 에너지 의존적인 과정으로서 물질대사와 관련되어 있는 것으로 생각되었으며, Pb 내성균주의 Pb 축적은 에너지 비의존적인 과정으로서 물질대사와 관련이 별로 없는 물리적인 과정에 의하여 축적되는 것으로 생각되었다. 각 중금속 내성균주들은 해당 중금속 축적능력에 비하여 낮았으나 타 중금속들의 축적능력도 있었으며, 여러가지 중금속들을 동일 농도로 복합처리 하였을 경우 해당 중금속들의 축적능력이 타 중금속들에 비하여 매우 높게 나타나 각 중금속 내성균주들의 해당 중금속 축적은 선택적인 과정에 의하여 축적되는 것으로 생각되었다.

• Asian-Australasian Journal of Animal Sciences
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• 제31권4호
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• pp.585-594
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• 2018

Objective: This study was to determine the bacterial diversity and monitor the community dynamic changes during storage of vacuum-packaged sliced raw beef as affected by Lactobacillus sakei and Lactobacillus curvatus. Methods: L. sakei and L. curvatus were separately incubated in vacuumed-packaged raw beef as bio-protective cultures to inhibit the naturally contaminating microbial load. Dynamic changes of the microbial diversity of inoculated or non-inoculated (control) samples were monitored at $4^{\circ}C$ for 0 to 38 days, using polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE). Results: The DGGE profiles of DNA directly extracted from non-inoculated control samples highlighted the order of appearance of spoilage bacteria during storage, showing that Enterbacteriaceae and Pseudomonas fragi emerged early, then Brochothrix thermosphacta shared the dominant position, and finally, Pseudomonas putida showed up became predominant. Compared with control, the inoculation of either L. sakei or L. curvatus significantly lowered the complexity of microbial diversity and inhibited the growth of spoilage bacteria (p<0.05). Interestingly, we also found that the dominant position of L. curvatus was replaced by indigenous L. sakei after 13 d for L. curvatus-inoculated samples. Plate counts on selective agars further showed that inoculation with L. sakei or L. curvatus obviously reduced the viable counts of Enterbacteraceae, Pseudomonas spp. and B. thermosphacta during later storage (p<0.05), with L. sakei exerting greater inhibitory effect. Inoculation with both bio-protective cultures also significantly decreased the total volatile basic nitrogen values of stored samples (p<0.05). Conclusion: Taken together, the results proved the benefits of inoculation with lactic acid bacteria especially L. sakei as a potential way to inhibit growth of spoilage-related bacteria and improve the shelf life of vacuum-packaged raw beef.

• Journal of Animal Science and Technology
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• 제45권4호
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• pp.559-568
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• 2003

본 연구는 유산균류 2종(Lactobacillus acidophilus, Lactobacillus bulgaricus)에 효모(Saccharomyces cerevisiae), 곰팡이 2종(Trichoderma, Rhizopus) 및 일반세균류 2종(Bacillus subitilis, Pseudomonas putida)이 혼합된 복합생균제를 육계사료에 0.1%, 0.3% 및 0.5% 수준으로 첨가하여 급여하였을 때 생산성, 영양소소화율, 유해가스 발생량 및 장내균총에 미치는 효과와 적정 첨가 수준을 구명하기 위하여 4처리, 3반복, 반복당 10씩 총 120수 공시하여 5주간의 사양시험과 5일간의 소화시험을 실시하였다. 3${\sim}$4주령의 증체량과 사료요구율은 생균제 0.1%와 0.3% 첨가구가 대조구와 생균제 0.5% 첨가구에 비하여 개선되었다(p<0.05). 5${\sim}$6주령의 증체량과 사료요구율은 생균제 0.3% 첨가구가 대조구에 비해 개선되었다(p<0.05). 사양시험 전기간(2${\sim}$6주)의 증체량과 사료요구율은 생균제 0.1%와 0.3% 첨가구가 대조구와 생균제 0.5% 첨가구에 비해 높았다(p<0.05). 건물소화율은 생균제 0.3% 첨가구가 대조구와 생균제 0.5% 첨가구에 비해 높았다(p<0.05). 6주령의 $NH_3$가스와 $H_2S$가스는 생균제를 첨가함으로써 대조구에 비하여 감소(p<0.05)하였으나, 4주령에는 대조구를 포함한 모든 처리구에서 유의차는 없었다. 맹장내 Lactobacillus sp.는 생균제 첨가구들이 대조구에 비해 증가되었으나, Coliforms은 생균제 첨가구들이 대조구에 비해 감소하였다. 이상의 결과를 종합하면, 증체량, 사료요구율, 영양소 소화율, NH3와 H2S 발생량 및 맹장내 균총은 복합생균제를 0.1${\sim}$0.3% 수준으로 첨가하여 급여하는 것이 가장 효과적인 것으로 사료된다.

• 동의생리병리학회지
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• 제16권2호
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• pp.348-352
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• 2002

This study was carried out to evaluate cytotoxic effects of Atractylodes macrocephala Koidz. (A. macrocephala Koidz.) extract on NIH 3T3 fibloblast. SK-MEL-3 (HBT 69) and KB (ATCC No, OCL 17) cell lines. Disruptions in cell organelles were determined by 3-(4,5-dimethylthiazol-2-y1)-2,5-diphenyl-2H-tetrazoliumbromide (MTT) assay. 10.2 mg/ml Concentration of A. macrocephala Koidz. extracts in SK-MEL-3 showed that their susceptibility (sensitivity) to these compounds decreased in the following order ; adriamycin > H₂O > ethyl acetate > ethyl alcohol > chloroform > n-hexane in SK-MEL-3 cell lines ; 5-FU > H₂O > n-hexane > ethyl acetate > ethyl alcohol > chloroform in KB cell lines. In order to develop an antimicrobial agent, A. macrocephala Koidz. was extracted with solvents. The minimal inhibitory concentrations (MICs) of each solvent extract of A. macrocephala Koidz. against microogranisms were also examined. Antimicrobial activities of ampicillin and ketoconazole as references were compared to those of each solvent extract of A. macrocephala Koidz. The antimicrobial activity of the ethyl acetate soluble extract of A. macrocephala Koidz. had growth inhibition activity against S. mutans and P. putida (MICs. 500 ㎍/ml). These results suggest that the ethyl acetate soluble extract of A. macrocephala Koidz. possessed antitumorous and antimicrobial agents

• 한국토양비료학회지
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• 제30권2호
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• pp.196-199
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• 1997

식물생장촉진 효과가 있는 Micrococcus sp., Bacillus subtilis, Enterobacter agglomerans, Bacillus megaterium, Pseudomonas putide, Pseudomans fluorescens, Cellulomonas sp., Staphylococcus xylosus등 8종의 혼합균주 배양액을 오이에 처리하였을때 작물에 미치는 영향을 조사한 결과는 다음과 같다. 1. 균처리구는 대조구에 비해 수량은 18% 증수되었으며, 주당 수확과수는 평균 5.1개 정도 많았다. 2. 만장, 엽장, 엽폭은 균처리구와 대조구간에 차이가 없었지만 줄기의 굵기, 2차측지 발생율, 유인 측지절수, 절성성은 균처리구가 대조구에 비해 양호하였다. 3. 토양의 물리성중 가밀도, 공극률은 차이가 없었으나 수분율은 균처리구가 대조구에 비해 높은 경향이었으며, 토양 화학성은 균처리구가 대조구에 비해 EC, 유기물, Ca, $NO_3-N$ 함량은 낮아졌으며, 그외 성분은 높은 경향이었다.