• 대한화학회지
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• 제22권6호
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• pp.386-395
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• 1978

여러 농도와 온도에서 Poly(trans-5-methyl-L-proline)을 trifluoroethanol 용매에서 정방향 변광회전, trifluoroethanol-n-butanol (1 : 4) 용매에서 역방향 변광회전을 시키면서 변광회전속도를 측정하였다. 이 두 방향의 변광회전 현상은 폴리머농도에 대하여 1차 반응이었다. 활성화에너지를 측정하기 위하여 변형된 Arrhenius식을 유도하였는데 이식은 물리적 성질과 농도와의 관계나 반응차수가 불확실한 반응에 이용할 수 있다. 정방향과 역방향 변광회전의 활성화에너지는 잔기몰당 각기 32.5와 33.5kcal이었고 이값은 polyproline 변광회전의 활성화에너지 (아미드결합의 공명에너지)보다 잔기몰당 10kcal가 높다. 이 과량의 활성화에너지는 폴리머아미드 결합이 시스-트란스 이성질화현상이 일어날 때 카르보닐기와 메틸기 사이에 생기는 입체장애에 의한 것이다.

• 한국응용과학기술학회지
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• 제37권1호
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• pp.145-152
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• 2020

본 연구에서는 붉나무 열매 Ethanol extract(ET)과 Ethyl acetate fraction(EA) 및 Butanol fraction(BT)을 천연보존제로서의 활용 가능성을 평가하기 위하여 항균활성을 측정 하였다. 항균활성은 Staphylococcus aureus(S. aureus), Staphylococcus epidermidis(S. epidermidis), Escherichia coli(E. coli), Pseudomonas aeruginosa(P. aeruginosa), Candida Albicans(Candida. A)에 대하여 Paper disc법으로 생육저해환과 최소저해농도(MIC)를 평가하였다. Paper disc법으로 생육저해환을 측정한 결과 ET, EA, BT 모든 시료에서 S. aureus, S. epidermidis, E. coli, P. aeruginosa 균주에서 생육저해환이 관찰되었고 BT에서는 Candida. A 균주에 대한 생육저해환이 추가로 관찰 되었다. MIC 측정결과 EA 시료가 S. aureus, S. epidermidis, E. coli, P. aeruginosa 대하여 가장 낮은 농도를 보였다. 따라서 본 연구의 결과는 붉나무 열매 추출물이 다양한 항균스펙트럼을 가지고 있어 화장품에서 천연보존제로 활용 가능성이 높다고 사료 된다.

• 한국토양비료학회지
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• 제48권5호
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• pp.485-491
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• 2015

This study was performed to investigate thermophilic bacteria from soil having broad antifungal spectrum against Rhizoctonia solani, Colletotrichum gloeosporioides, Phytophthora capsici, Fusarium oxysporum f.sp. lycopersici, and Botrytis cinerea. One isolate selected could resist heat shock of $60^{\circ}C$ for one hour, and had broad antifungal activity in dual culture assay against all tested fungal pathogens and was identified as Bacillus amyloliquefaciens Y1 using 16S rRNA gene sequence. Further investigation for antifungal activity of bacterial culture filtrate (BCF) and butanol crude extract (BCE) of various concentrations showed broad spectrum antifungal activity and fungal growth inhibition significantly increased with increasing concentration with highest growth inhibition of 100% against R. solani with 50% BCF and 11 mm of zone of inhibition against R. solani with 4 mg BCE concentration. Treatment of butanol crude extract resulted in deformation, lysis or degradation of C. gloeosporioides and P. capsici hyphae. Furthermore, B. amyloliquefaciens Y1 produced volatile compounds inhibiting growth of R. solani (70%), C. gloeosporioides (65%) and P. capsici (65-70%) when tested in volatile assay. The results from the study suggest that B. amyloliquefaciens Y1 could be a biocontrol candidate to control fungal diseases in crops.

• Natural Product Sciences
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• 제11권3호
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• pp.127-130
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• 2005

This study was carried out to investigate inhibitory effect of extracts from root cortex of Paeonia suffruticosa on ${\alpha}-glucosidase$ (EC 3. 2. 1. 20) and postprandial hyperglycemia. Methanol extract and organic solvent (n-hexane, ethyl acetate, butanol, aqueous) fractions from the crude drug were determined for the inhibitory activities against maltase, sucrase and ${\alpha}-amylase$. The methanol extract from the crude drug strongly inhibited maltase (72%) and sucrase (76%) at the concentration of $100\;{\mu}g/ml$. Among the fractions examined, the ethyl acetate fraction from the natural plant drug showed potent inhibitory effects on maltase (85%) and sucrase (81%) at the concentration of $100\;{\mu}g/ml$. The ethyl acetate fraction from root cortex of Paeonia suffruticosa also exhibited significant reductions (21%) of blood glucose elevation in mice loaded with maltose.

• 한국식품조리과학회지
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• 제14권1호
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• pp.114-118
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• 1998

In ordo. to develop the natural food preservative agent, freeze dried dandelion (Taraxcum platycarpum) was extracted with several solvents, and antimicrobial activity was investigated. The methanol extract obtained from the dandelion exhibited antimicrobial properties against five strains such as Bacillus subtilis, Escherichia coli, Staphylococcus aureus, Listeria monocytogenes, and Vibrio parahaemolyticus. The methanol extract at the concentration of 2000 $\mu\textrm{g}$/ml completely inhibited the growth of B. subtilis, E. coli, L. monocytogenes and V. parahaemolyticus. Antimicrobial activity of the ethylacetate fraction from the methanol extract of dandelion was the strongest fraction compare to those the other solvent fractions such as n-hexane, chloroform, n-butanol and water. The ethylacetate fraction showed the inhibitory effect at the concentration of 0.5 mg/disc on the growth of the food spoilage microorganisms.

• Journal of Nutrition and Health
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• 제28권11호
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• pp.1065-1072
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• 1995

Mugwort was successively fractionated with n-hexane, chloroform, ethyl acetate, n-butanol and water and the fractions were evaluated by their growth-promoting activites for Bifidobacterium sp. in vitro experiments. The growths of Bifidobacterium adolescentis, B. bifidum, B. infantis and B.longum were enhanced with the addition of the water fraction, while the fractions of chloroform and ethylacetate inhibited Clostridium perfringens. When the wate fraction was added to media at a concentration of 0.01-0.5%(w/v), the growhts of Bifidobacterium sp. were increased according to the concentration of water fraction used. The water fraction stimulated also the growth of lactobacillus acidophillus, whereas those of E. coli and Enterococcus faecalis were not affected. The growth-promoting activity of water fraction was stable at the range of pH 2 to pH 10 and kept in thermal treatment at 10$0^{\circ}C$ for 30 minutes.

• 생약학회지
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• 제28권2호
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• pp.80-83
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• 1997

The methanol extract of aerial part of Angelica keiskei Koidzumi exhibited a strong antimutagenic activity against aflatoxin $B_1\;(AFB_1)$. N-methyl-N'-nitro-N-nitrosoguanidine and 4-nitroquinoline-1-oxide in the Ames test with Salmonella typhimurium TA100. Cynaroside, isolated front ethylacetate fraction of the methanol extract Over silica gel, inhibited the mutagenicity of $AFB_1$ with an inhibition value of 96% at 1.0 mg/plate concentration and 87% at 0.5 mg/plate concentration. Other compounds, hyperoside, sucrose and luteolin-7-rutinoside, isolated from ethylactate or n-butanol fraction, also showed antimutagenic effect.

• Archives of Pharmacal Research
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• 제17권6호
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• pp.470-475
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• 1994

The butanol extract of paulownia tomentosa stem showed antibacterial activity against staphyl ococcus aureus (SG511, 285 and 503), Streptococcus pyogenes (A308 and A77) and Streptococcus farcium MD8b etc. The most active compound of the extractg was identified to be campneoside I, which had a minimal inhibitory concentration(MIC) of $150{\;}{\mu}g/ml$ against Strptococcus and Staphylococcus species. From such antibacterial activity, the methoxy group of campneoside I was posulated to be the essential element for the antibacterial activity.

• 한국식품조리과학회지
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• 제27권5호
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• pp.523-530
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• 2011

This study was conducted to investigate antimicrobial, antioxidant and anticancer activities of Opuntia humifusa (OH) petal extracts. The methanol and hexane extracts of OH petals showed their highest antimicrobial activity against Clostridium perfringens. The OH petal butanol fraction had the best antioxidative peroxynitrite scavenging activity among OH petal extracts. The DPPH scavenging activity of OH petals was lower than the peroxynitrite scavenging effect. The hexane and methanol fractions at a concentration of 200 ${\mu}g$/mL inhibited proliferation >80% in four kinds of human cervical cancer cells(B16F10, HepG2, HT-29 and MCF-7). In particular, the anticancer effect against B16F10 human skin cancer cells at the same concentration was higher than that in the other cancer cells.

• Applied Biological Chemistry
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• 제36권4호
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• pp.260-264
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• 1993

인삼을 조미제품의 첨가성분으로 이용할 때 그 NaCl 농도에서 인삼성분의 안정성을 규명하기 위하여, 미삼과 홍삼정을 NaCl 농도별로 처리하여 pH, 색상 및 ginsenosides 함량을 조사한 결과, 미삼의 경우 NaCl 농도가 증가 할수록 pH는 높아졌으나 홍삼정 시험구에서는 유의적인 변화가 없었다. 색상은 NaCl 농도가 증가 될수록 감소하였다. n-BuOH extract 수율은 5% NaCl 농도에서 감소하였고 그 이상의 농도에서는 증가하는 경향을 나타내었으며, 증감 범위는 홍삼정이 컸다. Ginsenosides 함량은 diol계 saponin인 ginsenoside-Re, $-Rb_1$, $-Rb_2$, -Rc, -Rd 및 triol계 saponin인 ginsenoside-Re 모두 5% NaCl 농도에서 감소하였고 그 이상의 농도에서 증가하는 경향이었으며, 특히 ginsenoside-Re가 가장 민감한 증감의 변화를 보였다.