• International Journal of Oral Biology
• /
• 제43권4호
• /
• pp.193-200
• /
• 2018

The purpose of this study is to determine if natural extracts could be used as an additive in oral health food made with Weissella cibaria CMU (oraCMU). Natural extracts of green tea, mulberry leaf, licorice, and propolis, which are reported to have antimicrobial activities, were selected and used in this study. The minimum inhibitory concentrations (MIC) of extracts on periodontal pathogens such as Fusobacterium nucleatum and Porphyromonas gingivalis and their synergy effects with oraCMU by the fractional inhibitory concentrations methods were measured. From the results obtained, all the extracts showed no effect on the growth of oraCMU. Green tea extract showed the best antibacterial activity with MIC of 1.8 mg/ml against both F. nucleatum and P. gingivalis. In addition, green tea extract had a synergistic effect with oraCMU against F. nucleatum. Therefore, these results suggested that green tea extract is available as an additive in oral health food made with oraCMU.

• 대한가정학회지
• /
• 제29권2호
• /
• pp.47-53
• /
• 1991

A. niger H-18 and A. fumigatus E-29 wrer selected for their strong abilities to produce cellulase. The λd numerical values of the cotton fabrics inoculated with A. niger H-18 and A. fumigatus E-29 were 580 nm for the both strains of molds. By the growth of molds, lightness, original color scale, and grey scale of the fabrics gradually decreased while chroma increased. The minimum inhibitory concentrations of mold-proofing agents, such as Leperon WL, 8-hydroxyquinoline copper acetate, trimethylol melamine and dimethyl ethylene urea was 50 ppm. Glycoxale was not effective at the above mentioned concentration. Since Leperon WL, trimethylol melamine and dimethyl ethylene urea effectively inhibited the growth of A. niger H-18 and A. fumigatus E-29, tensile strength and elongation of the fabrics were not changed. however, cotton fabrics treated with glycoxale of the fabrics were not changed. However, cotton fabrics treated with glycoxale and inoculated with A. niger H-18 and A. fumigatus E-29 showed decreased in tensile strength by 31.1% and 33.9%, respectively.

• 대한가정학회지
• /
• 제31권2호
• /
• pp.213-219
• /
• 1993

Aspergillus fumigatus(AF) and Penicillum citrinum(PC) were selected for their strong abilities to produce protease. The result are summarized as follows; 1. The λd numerical values of the silk fabrics with AF and PC were 560 and 580 nm for the both stains of molds. 2. By the growth of molds, lightness, original color scale, and grey scale of the fabrics gradually decreased while chroma increased. 3. The minimum inhibitory concentrations of mold proofing agents, such as Leperon WL, 8-hydroxyquinoline copper acetates, trimethylol melamine and dimethly ethylene urea was 50 ppm. 4. Glycoxale was not effective at the abovely concentration. Since Leperon WL, dimethyl ethylene urea effectively inhibited the growth of PC silk, tensile strengh and elongation of the fabrics were not changed.

• Journal of Nutrition and Health
• /
• 제36권2호
• /
• pp.147-153
• /
• 2003

In this study, Artemisia capillaries, which has been used as a folk remedy, was investigated for its antimicrobial activity. First, the Aremisia capillaris was extracted with methanol at room temperature, and fractionation of the methanol extracts from Artemisia capillaris was carried out using petroleum ether, chloroform, and ethyl acetate. Second, the antimicrobial activity of the Artemisia capillaris extracts was determined using a paper disc method and minimum inhibitory concentration of ethyl acetate extracts from Artemisia capillaris against food-borne pathogens and food spoilage bacteria was measured. Finally, the growth inhibition curve was determined using ethyl acetate extracts of Artemisia capillaris against Staphylococcus aureus and Salmonella typhimurium. The ethyl acetate extract of Artemisia capillaris showed strong antimicrobial activity against S. typhimurium at a concentration of 1,000 ppm. The 3,000 ppm of ethyl acetate extract from Artemisia capillaris retarded the growth of S. aureus and S. typhimurium for up to 6 hours.

• Journal of Microbiology and Biotechnology
• /
• 제22권6호
• /
• pp.872-881
• /
• 2012

The inhibitory effect of the Klebsiella pneumoniae ATCC 13883 strain caused by the hexane extract of Halimeda discoidea (Nor Afifah et al., 2010) was further evaluated by means of the microscopy view and its growth curves. The morphological changes of the K. pneumoniae ATCC 13883 cells were observed under the scanning electron microscope (SEM) and transmission electron microscope (TEM) after they were treated at minimum inhibitory concentration (MIC; 0.50 mg/ml) (Nor Afifah et al., 2010) for 12, 24, and 36 h. The results showed the severity of the morphological deteriorations experienced by the treated cells. The killing curve assay was performed for 48 h at three different extract concentrations (1/2 MIC, MIC, and 2 MIC). An increase in the extract concentration of up to 2 MIC value did significantly reduce the number of cells by approximately 1.9 $log_{10}$, as compared with the control. Identification of the potential compounds of the extract responsible for the antibacterial activity was carried out through the gas chromatography-mass spectrum (GC-MS) analysis of the active subfraction, and the compound E-15-heptadecenal was identified and suggested as the most potential antibacterial compound of this extract. The subsequent cellular degenerations showed by the data might well explain the inhibitory mechanisms of the suggested antibacterial compound. All of these inhibitory effects have further proven the presence of an antibacterial compound within H. discoidea that can inhibit the growth of K. pneumoniae ATCC 13883.

• 한국초지조사료학회지
• /
• 제36권1호
• /
• pp.1-6
• /
• 2016

2014/2015년도 전국 동계사료작물, 특히 벼 입모 중 파종했던 이탈리안 라이그라스의 월동 후 생육 상황은 매우 저조했다. 이탈리안 라이그라스의 생육저해 요인을 찾기 위해 충남 논산지역의 생육상황과 인근 대전지역의 기상을 분석한 결과는 다음과 같다. 월동 후인 2015년 2월 8일과 9일의 최저기온과 최대순간풍속은 각각 $-8.8^{\circ}C$와 10.7 m/s, $-12.4^{\circ}C$와 9.6 m/s로서 소낙눈을 동반한 강풍이 불면서 온도도 매우 낮았는데, 이는 토양 과습으로 토양 표면에 노출되어 있던 이탈리안 라이그라스의 뿌리 생장에 매우 불리하게 작용하였다. 연이어 2월 12, 13, 14일에도 각각 $-4.1^{\circ}C$와 11.6 m/s, $-5.6^{\circ}C$와 10.3 m/s, $-4.7^{\circ}C$와 7.5 m/s의 저온과 강풍피해를 받았다. 더욱이 1월부터 지속된 가뭄현상으로 건조상태가 지속되다가 2월 15, 16일에 19 mm의 강우가 내렸으나 생육을 회복하기엔 역부족이었다. 2월 26, 27, 28일에도 $-1.8^{\circ}C$와 13.7 m/s, $-3.5^{\circ}C$와 10.6 m/s, $-4.1^{\circ}C$와 6.8 m/s의 저온과 강풍피해가 있었다. 3월 3일까지 고사개체가 59% 이상으로 많았으며 3월 4일부터 12일까지 9일간의 저온과 강풍은 이탈리안 라이그라스를 생육 회복불능상태로 몰고 갔다. 따라서 2014/2015년의 이탈리안 라이그라스 수량감소의 주원인은 다음과 같이 분석되었다. 2014년 10월, 11월의 강우로 인하여 벼 수확 후 볏짚수거가 지연되어 볏짚 밑에 눌려 연약하게 자란 개체가 월동 후 저온에 고사되었다. 배수로 미설치로 논 토양 표면의 수분이 과다하여 뿌리를 땅속으로 내리지 못한 채 월동하게 된 이탈리안 라이그라스가 봄에 서릿발 및 가뭄과 강풍을 동반한 저온피해를 받아 뿌리가 말라버려 작물이 고사되어 버리는 상황이 발생되었다.

• Mycobiology
• /
• 제45권1호
• /
• pp.25-30
• /
• 2017

Metal-based drugs, such as 1,10-phenanthroline, have demonstrated anticancer, antifungal and antiplasmodium activities. One of the 1,10-phenanthroline derivatives compounds (1)-N-2-methoxybenzyl-1,10-phenanthrolinium bromide (FEN), which has been demonstrated an inhibitory effect on the growth of Candida spp. This study aimed to explore the in vitro antifungal activity of FEN and its effect on the membrane integrity of Candida albicans. The minimum inhibitory concentration (MIC) and the minimum fungicidal concentration (MFC) of FEN against planktonic C. albicans cells were determined using the broth microdilution method according to the Clinical and Laboratory Standards Institute guidelines. Cell membrane integrity was determined with the propidium iodide assay using a flow cytometer and were visualized using scanning electron microscopy (SEM). Planktonic cells growth of C. albicans were inhibited by FEN, with an MIC of $0.39-1.56{\mu}g/mL$ and a MFC that ranged from 3.125 to $100{\mu}g/mL$. When C. albicans was exposed to FEN, the uptake of propidium iodide was increased, which indicated that membrane disruption is the probable mode of action of this compound. There was cells surface changes of C. albicans when observed under SEM.

• 한국미생물·생명공학회지
• /
• 제46권1호
• /
• pp.40-44
• /
• 2018

Gram 양성세균의 생육을 억제하는 세균을 청주시 무심천 토양에서 분리하였으며, 16S rRNA 유전자 염기서열 분석 결과 Pseudomonas otitidis PS로 동정하였다. PS 균주는 0.5%의 glucose가 포함된 1% soybean meal 배지에서 2차 대사 산물로서 최대 약 0.1%의 수율로 항생물질을 생산하였다. 항생물질 성분은 ethyl acetate로 추출하였으며, Staphylococcus aureus KCTC 1261에 대한 minimum inhibitory concentration은 $2{\mu}g/ml$이었다. 이 성분은 siderophore 활성을 띠어서 chrome azurol S 평판배지에서 주황색 halo를 나타내었으며, 철이 제거되면 생육 억제 효과는 감소하였다. Ascorbic acid 같은 환원제를 첨가하거나 혐기적 환경에서는 항생물질 활성을 잃으므로 PS 항생물질은 활성산소를 방출하여 bactericidal activity를 갖는 것으로 보인다.

• 한국식품저장유통학회지
• /
• 제5권3호
• /
• pp.299-304
• /
• 1998

전통민속주 제조에 널리 사용되어온 국화꽃잎에서 에탄올 추출하여 식품부패에 관련된 미생물을 대상으로 항균활성을 검색하고 에탄올 추출물의 농도별 항균활성과 최저 생육저해 농도를 조사하였다. 국화 에탄올 추출물의 항균활성은 산국이 B. subtilis에 대해 항균활성이 높게 나타난 반면, 소국은 E.coli에 대한 항균활성이 산국보다 다소 높게 나타났다. 8종의 부패균에 대한 에탄올 추출물의 항균활성은 산국이 소국에 비하여 높게 나타났으며, 산국 에탄올추출물의 최소저해농도는 60-70${\mu}\ell$/ml로 나타났다. 산국 에탄올추출물은 그람양성세균에서 보다 그람음성세균에 대한 항균활성이 다소 높았으나, 100${\mu}\ell$ 농도에서는 그람음성 및 양성 세균 모두 생육이 크게 저해되었다. 따라서 전통민속주의 보존효과 측면에서 산국 에탄올추출물이 우수한 것으로 나타났다.

• International Journal of Oral Biology
• /
• 제44권4호
• /
• pp.152-159
• /
• 2019

The oral care probiotic strain Weissella cibaria CMU (oraCMU) inhibits volatile sulphur compounds associated with halitosis, presumably by inhibiting the growth of associated oral pathogens. In the present study, we investigated whether oraCMU inhibits the production of these compounds by suppressing the expression of mgl. This gene encodes L-methionine-α-deamino-γ-mercaptomethane-lyase (METase) and is involved in the production of methyl mercaptan (CH₃SH) by Porphyromonas gingivalis. Therefore, we specifically investigated the effects of oraCMU on the growth, CH₃SH production, METase activity, and mgl expression of P. gingivalis. The minimum inhibitory concentrations of cell-free supernatant and secreted proteins from oraCMU were 125 mg/mL and 800 ㎍/mL, respectively. At sub-minimum inhibitory concentration levels, these metabolites inhibited CH₃SH production, but they also reduced P. gingivalis viability. Only heat-killed oraCMU decreased CH₃SH production without affecting P. gingivalis viability. Heat-killed oraCMU also inhibited METase activity toward L-methionine and mgl mRNA expression (p < 0.05). In summary, we demonstrated the inhibition of volatile sulphur compounds via the antimicrobial action of oraCMU and, for the first time, the inhibition of such compounds by heat-killed oraCMU, which occurred at the molecular level.