• 한국식품영양과학회지
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• 제30권4호
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• pp.641-645
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• 2001

골뱅이의 가공 부산물인 내장의 효율적인 이용을 위하여 단백질 가수분해효소인 bromelain을 함유하는 파인애플과 actinidin을 함유하는 참다래의 과즙 첨가하여 젓가을 제조하였다. 파인애플 과즙과 참다래 과즙은 각각 52unit/mL, 248 unit/mL의 단백질 가수분해 효소활성을 나타내었다. 마쇄한 골뱅이의 내장을 염농도 12.5%와 과즙 25, 50, 100 mL 첨가하여 1$0^{\circ}C$에서 숙성하였다. 파인애플 과즙을 첨가한 젓갈에서 참다래를 첨가한 경우보다 숙성 중 pH의 변화가 다소 많으며 아미노 질소가 많이 생성되었고 총질소함량과 총균수는 숙성기간이 연장도리수록 증가하는 경향을 보이고 있으나, 첨가한 과즙의 종류와 양에 따른 연관성은 발견하지 못하였다. 한편, 젓갈의 숙성 중의 안전성을 확인하기 위하여 측정한 대장균군 시험에서는 본 연구에서 제조된 모든 젓갈에서 음성으로 확인되어 위생적으로 적합한 것으로 판정되었다.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제27권6호
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• pp.523-527
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• 2005

Allograft donations are commonly found to be contaminated. The most of tissue banks has promoted the use of ionizing radiation for the sterilization of biological tissues. The potential for transmission of human infectious diseases and contamination of microorganism has created serious concern for the continued clinical use of hard and soft-tissue allografts. Tissue banks have employed 15-25kGy for sterilization of hard and tendon allografts, which, according to the national standards, approaches the level at which the tissue quality is adversely affected for transplantation. The donations of allogeneic tissues to the Korea Tissue Bank over a 2-year period were reviewed, and the incidence and bacteriology of contamination were detailed. Clinical outcomes were determined for donors who had positive cultures at the time of retrieval and during the processing and they were compared with those of post sterilization. After exposure of the frozen block bone to 25kGy and the processed tissues to 15kGy of gamma irradiation, the authors were able to demonstrate complete inactivation of the bacteria. The aim of this study was to obtain the effects of gamma irradiation and the irradiation dose according to the type of tissue, through conventional microbiologic test without on influence of biocompatibility in allografts. The contamination rate after the final irradiation sterilization is 0% in the processed allografts. This may be due to the fact that the gamma radiation and processing steps are effective to control contamination.

• 한국식품저장유통학회지
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• 제10권3호
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• pp.278-283
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• 2003

김치 제조시 위생적 품질 개선을 위하여 ethanol과 천연항균물질인 polylysine의 복합 첨가를 검토하였다. Ethanol 농도를 0.3, 0.6 및 0.9%로 첨가하여 김치를 제조한 후 1$0^{\circ}C$에 저장하면서 3일 간격으로 총균수, 대장균군, 젖산균, 곰팡이 및 효모 등을 비교 측정한 결과, ethanol의 첨가는 대장균군과 젖산균의 생육 억제에 있어 보다 효과적인 것으로 나타났으며, ethanol 농도 0.6% 첨가시부터 미생물 생육 억제 효과가 뚜렷하게 나타났다. 또한 ethanol 0.6%를 첨가하여 담근 김치는 저장중 pH 저하 및 산도 상승에 대한 지연효과를 보여주었고, 저장중 관능특성의 변화에서도 신냄새, 이취, 신맛, 이미, 조직감 및 종합적 기호도의 모든 항목에서 가장 우수한 것으로 평가되었다. Polylysine은 단일 사용시보다는 0.6% ethanol과 복합 첨가했을 경우 미생물 생육 억제에 상승효과를 보였으나 관능평가에서 이미 및 이취를 느끼는 것으로 평가되어 0.6% ethanol 단일 첨가가 미생물 증식 억제 및 발효 지연에 가장 효과적인 것으로 나타났다.

• 한국식품과학회지
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• 제37권5호
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• pp.844-849
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• 2005

본 연구에서는 천연물질유래 살균소독제인 CaO가 깻잎 중 존재하는 자연균총, E. coli, L. monocytogenes, S. typhimurium에 미치는 저해효과를 알아보았고 chlorine, ethanol, hydrogen peroxide 등과 같은 주요 chemical sanitizer와 비교하였다. CaO를 농도별(0.05-0.2%), 시간별(2-10분) 처리했을 때 총호기성균은 $0.55-1.49\;log_{10}CFU/g$, 대장균은 $0.85-2.56\;log_{10}CFU/g$, E. coli는 $0.16-1.08\;log_{10}CFU/g$, L. monocytogenes는 $0.30-1.14\;log_{10}CFU/g$, S. typhimurium은 $0.19-1.07\;log_{10}CFU/g$의 감소를 보였으며, 특히 0.2%에서는 일반적으로 사용되는 100 ppm의 chlorine, 20% 이내의 ethanol, 1%의 hydrogen peroxide만큼 우수한 살균효과를 보였다. 본 연구에 따라 CaO는 기존의 화학적 살균제를 대체할 수 있는 좋은 천연물질유래 살균소독제로 활용될 수 있을 것이다.

• 한국식품과학회지
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• 제38권2호
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• pp.262-267
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• 2006

본 논문은 새로운 항암소재를 검색하기 위하여 식품으로부터 곰팡이를 분리하고 그 대사산물을 이용하여 수종의 암세포주의 생육을 대한 억제 물질을 탐색하고자 하며, 이를 바탕으로 새로운 항생물질 연구의 기초자료를 확보하고 결과물의 응용도를 모색하고자 실험을 수행하였다. 식품으로부터 총 72종의 곰팡이를 분리 하였고, 전면 및 후면의 색, 모양. 성장속도에 따라 4가지 group로 나누어 실험에 사용하였다. 그리고 그 대사산물(배양무, 균체)을 ethly acetate로 추출하여, 총 6종의 암세포주에 대하여 MTT assay을 실험하였다. 그 ruf과 A, B, C, D group 중 D group에서 가장 높은 증식 억제를 확인 하였으며, D4의 증식억제 효과가 가장 높음을 확인하였다. 위암 세포주인 KATO III, AGS, SUN-668에 대한 증식억제 효과는 30-98%로 나타났으며, 간암 세포주인 Hepa1c1c7, HepG2에는 10-98%, 유방암 세포주인 MDA-MB-231에 대해서는 25-90%의 증식억제 효과를 확인하였다. 배양물과 균체의 항암성은 개체에 따라 약간의 차이는 있으나, 배양물이 대부분 우수한 것으로 확인되었다.

• 펄프종이기술
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• 제33권5호
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• pp.1-11
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• 2001

In the past, abundant and clean water was available for paper mills'use. However, the growth of population and industry made water less available nowadays. Also, environmental regulation limits wastewater discharge, which affects mill operation cost. Therefore, paper mills are under pressure to use more recycled water and mill system closure. As a result, chemical and physical parameters of water are changing and new environment if being created for microorganisms in paper mill system as well. The more soluble or suspended organic materials are increased as more water is recycled and less or scarce dissolved oxygen is available, depending on the degree of recycled water usage. Microorganism flora ill paper mill system will be a1so shifted according to the environmental change of mill system. Anaerobic bacteria, including sulfate reducing bacteria (SRB), will be dominant in the system as very low or almost no oxygen available in the system. Nevertheless, it is common in domestic paper mills that employ the same and old biocides as a means of microbial control, and microbiological control is often less recognized or even neglected. The right biocide selection for increased reductive environment of mills is critical for operation and estimated loss from paper quality defects such as sheet break, holes due to microbiological cause is tremendous compared to the microbiological control cost. It is imperative to investigate and diagnosis the environmental change of mills for right control of cumbersome microorganisms. Several useful diagnosis tools, including new technology employing OFM(Optical Fouling Monitor) in situ, are illustrated.

• Restorative Dentistry and Endodontics
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• 제21권2호
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• pp.470-488
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• 1996

The end products of the metabolism of the oral microorganism, organic acids, are an element that produces dental caries. Four organic acids in plaque fluid, lactic acid, acetic acid, succinic acid, propionic acid which take the important role in producing dental caries, were chosen to evaluate the effect of acid type and concentration. The subject, $100{\mu}m$ in thickness, were immersed in acid-buffer solution which has the different acid concentration of 10mM, 25mM, 50mM, 100mM and pH 4.3 and degree of saturation was $0.153{\pm}0.003$ kept in constant and were operated to produce artificial caries under different demineralization time (1, 2, 3 day) at x25. The results were obtained by observing under polarizing microscope at x25. 1. The subsurface lesion, specific finding of incipient enamel caries, showed positive birefringence. but surface zone and sound enamel showed negative birefringence. 2. The demineralization rate of enamel was increased as the acid concentration increased. 3. The subsurface lesion showed increasing depth in the order of lactic, acetic, propionic acid, succinic acid. 4. The concentration of organic acid in artificial caries system had an independent effect on demineralization rate in enamel under the constant pH and degree of saturation. The result of this study showed that not only pH and the acid strength but the concentration of organic acid had an independent effect on demineralization rate in early enamel caries. And through the further research on the factors influencing enamel demineralization, it will be necessary to develop an effective caries preventive therapy.

• 한국토양비료학회지
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• 제48권6호
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• pp.634-640
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• 2015

Chelating agents have been proposed to improve the efficiency of phytoextraction of heavy metal hyperaccumulator. However, little studies to elucidate mechanism of chelating agents to increase cadmium (Cd) extractability have been conducted. The objectives of this study were to evaluate effect of different chelating agents on Cd extractability and to determine mechanism of Cd mobilization affected by these agents. An arable soil was spiked with inorganic Cd ($CdCl_2$) to give a total Cd concentration of $20mgCdkg^{-1}$. Ethylenediaminetetraacetic acid (EDTA) and citric acid (CA) were selected and mixed with the arable soil at the rates of 0 and $5mmolkg^{-1}$. The mixture soils were incubated at $25^{\circ}C$ for 4 weeks in dark condition. Concentration of F1 Cd fractions (water soluble) significantly increased with addition of EDTA but did not changed with addition of CA. Especially; concentration of F5 Cd fractions (residual) significantly increased with addition of CA. Increase in water soluble with EDTA might be attributed to complexation of Cd and EDTA. Dissolved organic carbon concentration significantly increased with EDTA addition, but did not with CA implying that considerable amount of CA was decomposed to inorganic carbon by microorganism. Log activity of carbonate ($CO_3{^{2-}}$) which might be generated from CA increased with addition of CA. Increase in residual Cd fraction might be due to precipitation of Cd as $CdCO_3$. As a result, EDTA was effective in increasing Cd extractability, by contrast CA had significant effect in reducing Cd extractability.

• 한국지하수토양환경학회지:지하수토양환경
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• 제24권4호
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• pp.1-10
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• 2019

Recently, groundwater contamination by mixed occurrence of arsenic (As) and nitrate ($NO_3{^-}$) has been a serious environmental issue all around world. In this study, we investigated the microbial As(III) oxidation characteristic under denitrification process to examine the feasibility of the microbial consortia in wetland sediment to simultaneously treat these two contaminants. The detail objectives of this study were to investigate the effects of $NO_3{^-}$ on the oxidation of As(III) in anaerobic environments and observe the microbial community change during the As oxidation under denitrification process. Results showed that the As(III) was completely and simultaneously oxidized to As(V) under denitrification process, however, it occurred to a much less extent in the absence of sediment or $NO_3{^-}$. In addition, the significant increase of As(III) oxidation rate in the presence of $NO_3{^-}$ suggested the potential of As oxidation under denitrification by indigenous microorganisms in wetland sediment. Genera Pseudogulbenkiania, and Flavisolibacter were identified as predominant microbial species driving the redox process. Conclusively, this study can provide useful information on As(III) oxidation under denitrifying environment and contribute to develop an effective technology for simultaneous removal of As(III) and $NO_3{^-}$ in groundwater.

• 한국환경과학회지
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• 제30권11호
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• pp.945-956
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• 2021

In this study, the effects of single and binary heavy metals toxicity on the growth and phosphorus removal ability of Bacillus sp.. known as be a phosphorus-removing microorganism, were quantitatively evaluated. Cd, Cu, Zn, Pb, Ni were used as heavy metals. As a result of analysis of variance of the half of inhibition concentration and half of effective concentration for each single heavy metal treatment group, the inhibitory effect on the growth of Bacillus sp. was Ni < Pb < Zn < Cu < Cd. And the inhibitory effect on phosphorus removal by Bacillus sp. was Ni < Pb < Zn < Cu < Cd. When analyzing the correlation between growth inhibition and phosphorus removal efficiency of a single heavy metal treatment group, a negative correlation was found (R² = 0.815), and a positive correlation was found when the correlation between IC₅₀ and EC₅₀ was analyzed (R² = 0.959). In all binary heavy metal treatment groups, the interaction was an antagonistic effect when evaluated using the additive toxicity index method. This paper is considered to be basic data on the toxic effects of heavy metals when phosphorus is removed using phosphorus removal microorganisms in wastewater.