• 한국식품영양학회지
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• 제17권4호
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• pp.436-441
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• 2004

소비자의 수요 변화에 부응한 고품질$.$안전 농산물 생산 요구가 증대되고 있는 현실에서, 생산자와 소비자가 신뢰할 수 있는 미생물 안전성이 확보된 안전 농산물 생산을 위한 기술 개발 및 연구가 필요한 실정이다. 본 연구에서는 주로 생식으로 섭취되는 엽채류 중에서 상추에 잔류하는 미생물을 경감시키기 위한 살균액 처리방법들 중에서 농민들이 생산 단계에서 쉽게 이용할 수 있고 90% 이상(1/10 수준으로)의 효과적인 미생물 경감 효과를 보이는 3% 과산화수소수 용액에서 1분 이상 침지하는 방법을 최적의 미생물 경감 방법으로 선정하였다. 이를 농산물 생산단계에서 농민들이 이용한다면 농산물의 안전성 증진 및 부가가치 향상에 크게 기여할 뿐만 아니라 최소가공기술을 이용한 신선 농산물의 가공 연구에도 유용하게 쓰일 수 있을 것으로 판단된다.

• 유기물자원화
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• 제16권1호
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• pp.53-61
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• 2008

07년 1월부터 11월까지 하수처리장별로 각각의 세균에 대한 계절별 분포도를 조시하였다. 조사에 사용된 미생물은 호기성 및 통성혐기성 종속영양세균으로 대표되는 총 세균과 지표생물군인 대장균, 대장균군, 장내세균군 및 포도상규군과 효모/곰팡이로 구성하였다. 총 세균 및 대장균 대장균군, 장내세균군 등의 지표생물군의 경우엔 대체로 온도가 높은 하절기에 균체수가 증가하고 있는 것으로 나타난 반면, 식중독의 원인균인 황색포도상구균의 경우, 대부분의 하수처리장에서 오히려 11월과 1월에 균체수가 증가하는 등, 계절과 관계없이 출현하는 양상을 나타냈다. 한편, 방류수의 소독처리방법과 균체생성은 큰 상관관계가 없는 것으로 나타났으나, 작은규모의 마을하수의 경우 도시하수와 비교하여 균체수가 감소하고 있는 것으로 조사되었다.

• 한국식품저장유통학회지
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• 제3권2호
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• pp.149-154
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• 1996

In order to develovpment of new sterilizing method applied to food industry, effects of ozone treatment on microorganisms, associated with food hygiene were investigated. Microorganisms were immersed in water and sparged with ozonised air(ozone concentration, 3mg liter-1) at an air flow rate of 5 liter min-1. When organisms were treated with benzoic acid and sorbic acid of 0.4∼1.0g/$\ell$, respectively, they were not dectable perfectly. Sodium benzoate had an effect on Penicillium islandicum. When bacteria were sparged with ozonised air, Pseudomonas aeruginosa completely inhibited at 60 minutes, and the killing Aspergillus flavus and Penicillium islandicum. Also, all of bacteria were inactivated after immersed with ozonated water for 10minutes, but two fungal species were not effective.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2000년도 추계학술대회
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• pp.196-201
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• 2000

The influence of adsorption on cadmium toxicity to soil microorganisms in smectite-rich soils and sediments was quantified as a function of solution and sorbent characteristics. Adsorption and surface complexation experiments were conducted to infer Cd sorption mechanisms to a reference smectite and three fractions of a Veritsol soil, and to elucidate the effects of the surface complexation on Cd bioavailability and toxicity in soils and sediments. Cadmium adsorption isotherms conformed to the Langmuir adsorption model, with adsorptive capacities of the different samples dependent on their characteristics. Equilibrium geochemical modeling (MINTEQA2) was used to predict the speciation of Cd in the soil suspensions using Langmuir and Triple Layer surface complexation models. The influence of adsorption and surface complexation on cadmium toxicity to soil microorganisms was assessed indirectly through the relative change in microbial hydrolysis of fluorescein diacetate (FDA) as a function of total Cd concentration and sorbent characteristics. Adsorption decreased the toxicity of Cd to soil microorganisms. Inner-sphere complexation is more effective than outer-sphere complexation in reducing the bioavailability and toxicity of heavy metals in soils and sediments.

• 한국축산식품학회:학술대회논문집
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• 한국축산식품학회 2006년도 정기총회 및 제37차 춘계 국제학술발표대회
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• pp.277-280
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• 2006

This study was carried out to investigate the effect of HPLT on the inactivation rates of microorganisms in raw milk depending on the pressurization time and temperature. Raw milk samples were submitted to HPLT of 200 MPa at -4, 4, 12 and $20^{\circ}C$, respectively. Inactivation increased with pressurization time and HPLT of microorganisms at 200 MPa was time dependent at any temperature. At sub-zero temperature of $-4^{\circ}C$, high pressure pasteurization was the most effective in inactivating microorganisms.

• Environmental Engineering Research
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• 제10권1호
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• pp.1-6
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• 2005

Hexavalent chromium in aqueous solutions was successfully removed via sorption and reduction in the presence of waste leaves. Cr(VI) removal followed a first-order reaction, and removal rates were proportional to the amount of waste leaves used in the tests. Most of Cr(VI) were removed via sorption in early stages of the tests, but the reduction reaction played a significant role in Cr(VI) removal later. Solution pHs were continuously decreased due to the microbial activity, which was induced from the microorganisms attached on waste leaves. The decreased solution pHs further enhanced the sorption and reduction of Cr(VI). To characterize the microorganisms found in the tests, a denaturing gradient gel electrophoresis (DGGE) method was used. The majority of microorganisms were composed of Bacillus sp. which can reduce Cr(VI). Thus, waste leaves can be effective reactive media for the treatment of Cr(VI) in the subsurface.

• 한국유기농업학회지
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• 제12권4호
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• pp.427-436
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• 2004

This study was conducted to investigate the effect of microbial product on microorganisms in soil and the growth of leaf lettuce. The test material were treated with chitosan, wood vinegar and EM activity liquid, and treatment concentration was 50 times solution and 100 times solution level with foliar application. The results were summarized as follows : Among foliar application of microorganisms treatments diluted by chitosan 100 times solution level was effective considering growth of leaf lettuce as compared other dilutions and control plot. Change of microorganism number in the soil for cultivation of chinese cabbages and leaf lettuce was increased with microorganism treatment plot as compared with control plot. Specially chitosan 100 times solution level showes the most significant effect.

• 대한화장품학회지
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• 제23권3호
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• pp.122-127
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• 1997

Chitin and chitosan have been almost neglected until 1960's although they second largest biomass on earth. Chitosan is a partially deacetylated chitin and belongs to the class of cationic biopolymers. We investigated the antimicrobial activity of chitosan as natural preservatives in cosmetic products. Antimicrobial activity of chitosan against some microorganisms was investigated. The results indicated that chitosan had an effectiveness against some bacteria. We found that chitosan had minimum inhibitory concentataions as low as 100 ppm to S. aureus ATCC 6538, E. coli ATCC 1634 and P. aeruginosa KCTC 2004. But there was not effects to Asp. Niger ATCC 1374 at 1,000 ppm. Also, formuias preserved with chitosan have been subjected to preservative efficacy tests to some microorganisms. Formla preserved with 0.5% chitosan had an effective antimicrobial activity against the Gram (+) and Gram (-) bacteria but not fungi. It is possible to dertermine the formulas with chitosan, which would be effective to reduce the artificial preservatives.

• 한국유기농업학회지
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• 제6권1호
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• pp.35-43
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• 1997

For the purpose of acquiring microbial agents that can be utilized to billogically control the major airborne disease to apple trees, such as canker(Valsa ceratosperma), the effective microorgaisms were isolated, tested for antagonistic activity to the pathogen causing major disease to apple trees and identifed. Screening of more than 3, 000 species of microorganisms collected in nature for them antagonistic action to the pathogen, Valsa ceratosperma causing disease to apple tree resulted in selection of effective species. Out of the 11 species, one species designated as CAP141 demonstrated outstanding activity. The bacterial strain, CAP141 exerted antagonistic efficiency of 65% on Valsa ceratosperma. The CAP141 was identified as a bacterial strain to Bacillus subtilis based on morphology, culture conditions, and physio-biochemical characteristics.

• Journal of Microbiology and Biotechnology
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• 제22권7호
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• pp.1015-1020
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• 2012

Antifungal cement mortar or microbiological calcium carbonate precipitation on cement surface has been investigated as functional concrete research. However, these research concepts have never been fused with each other. In this study, we introduced the antifungal calcite-forming bacteria (CFB) Bacillus aryabhattai KNUC205, isolated from an urban tunnel (Daegu, South Korea). The major fungal deteriogens in urban tunnel, Cladosporium sphaerospermum KNUC253, was used as a sensitive fungal strain. B. aryabhattai KNUC205 showed $CaCO_3$ precipitation on B4 medium. Cracked cement mortar pastes were made and neutralized by modified methods. Subsequently, the mixture of B. aryabhattai KNUC205, conidiospore of C. sphaerospermum KNUC253, and B4 agar was applied to cement cracks and incubated at $18^{\circ}C$ for 16 days. B. aryabhattai KNUC205 showed fungal growth inhibition against C. sphaerospermum. Furthermore, B. aryabhattai KNUC205 showed crack remediation ability and water permeability reduction of cement mortar pastes. Taken together, these results suggest that the $CaCO_3$ precipitation and antifungal properties of B. aryabhattai KNUC205 could be used as an effective sealing or coating material that can also prevent deteriorative fungal growth. This study is the first application and evaluation research that incorporates calcite formation with antifungal capabilities of microorganisms for an environment-friendly and more effective protection of cement materials. In this research, the conception of microbial construction materials was expanded.