• The Plant Pathology Journal
• /
• 제19권4호
• /
• pp.189-194
• /
• 2003

The effects of prochloraz on membrane permeability and germination of uredospores of Puccinia recondita were investigated to determine its potential mode of action on wheat leaf rust control activity. Disease control activity of ergosterol biosynthesis inhibitors (EBIs) and their activities on uredospore membrane permeability and germination were examined with wheat leaf rust pathogen, both in vitro and in vivo. While wheat leaf rust was not controlled by prochloraz, electrolytic leakage and spore germination of P. recondita uredospore was the highest with the use of prochloraz among the eight fungicides tested. Prochloraz stimulated uredospore of P. recondita to germinate at a higher ratio. Although certain EBIs, such as hexaconazole, showed excellent control activity, their effects on uredospore membrane permeability and germination was much inferior to prochloraz. Therefore, results of this study suggest that effects of EBIs on membrane permeability and germination of uredospore are not always correlated with their disease control activity.

• 천문학논총
• /
• 제27권4호
• /
• pp.281-284
• /
• 2012

We utilize AKARI's slitless spectroscopic capability to detect the $3.3{\mu}m$ polycyclic aromatic hydrocarbons (PAHs) emission and measure star formation (SF) activity for various AKARI programs. First, we obtain $2{\sim}5{\mu}m$ spectra of 20 flux-limited galaxies with mixed SED classes in order to calibrate the $3.3{\mu}m$ PAH luminosity ($L_{PAH3.3}$) as a star formation rate (SFR) indicator. We find that $L_{PAH3.3}$ correlates with $L_{IR}$ as well as with the $6.2{\mu}m$ PAH luminosity ($L_{PAH6.2}$). The correlations does not depend on SED classes. We find that ULIRGs deviate from the correlation between PAH luminosities and $L_{IR}$, while they do not for the correlation between PAH luminosities. We suggest possible effects to cause this deviation. On the other hand, how AGN activity is linked to SB activity is one of the most intriguing questions. While it is suggested that AGN luminosity of quasars correlates with starburst (SB) luminosity, it is still unclear how AGN activity is connected to SF activity based on host galaxy properties. We are measuring SFRs for the LQSONG sample consisting of reverberation mapped AGNs and PG-QSOs. This is an extension of the ASCSG program by which we investigated the connection between SB and AGN activities for Seyferts type 1s at z ~ 0.36. While we found no strong correlation between $L_{PAH3.3}$ and AGN luminosity for these Seyferts 1s, $L_{PAH3.3}$ measured from the central part of galaxies correlates with AGN luminosity, implying that SB and AGN activities are directly connected in the nuclear region.

• The Plant Pathology Journal
• /
• 제24권3호
• /
• pp.317-321
• /
• 2008

In a search for plant extracts with in vivo antifungal activity for plant diseases, we found that the methanol extract of Myristica malabarica fruit rinds effectively suppressed the development of several plant diseases. The methanol extract exhibited potent 1-day protective activity against rice blast, tomato late blight, wheat leaf rust and red pepper anthracnose. It also showed 7-day and 4-day protective activities against the plant diseases. Three antifungal resorcinols were isolated from the methanol extract of M. malabarica fruit rinds and identified as malabaricones A(MA), B(MB), and C(MC). Inhibitory activity of the three resorcinols against mycelial growth of plant pathogenic fungi varied according to compound and target species. All three compounds effectively reduced the development of rice blast, wheat leaf rust and red pepper anthracnose. In addition, MC was highly active for reducing the development of tomato late blight. This is the first report on the antifungal activities of malabaricones against filamentous fungi.

• The Plant Pathology Journal
• /
• 제23권4호
• /
• pp.318-321
• /
• 2007

Pine wood nematode, Bursaphelenchus xylophilus, causes pine wilt disease in a number of Pinus species, which is one of the most serious plant diseases in forest, Korea. In the course of a search for nematicidal substances from endophytic fungi, Fusarium oxysporum EF119 out of the 23 fungal strains tested showed the strongest activity to B. xylophilus. Two nematicidal substances were isolated and identified as bikaverin and fusaric acid. Fusaric acid showed somewhat higher nematicidal activity against B. xylophilus than bikaverin; fusaric acid and bikaverin, at $100{\mu}g/ml$, killed B. xylophilus with mortality values of 50% and 43%, respectively. In addition, both compounds acted synergistically. This is the first report on the nematicidal activity of bikaverin and fusaric acid.

• Bulletin of the Korean Chemical Society
• /
• 제33권12호
• /
• pp.4007-4014
• /
• 2012

Efficient synthetic route to novel 4'-fluorinated 5'-deoxythreosyl phosphonic acid nucleosides was described from glyceraldehyde using Horner-Emmons reaction in the presence of triethyl ${\alpha}$-fluorophosphonoacetate. Glycosylation reaction of nucleosidic bases with glycosly donor 14 gave the nucleosides which were further phosphonated and hydrolyzed to reach desired nucleoside analogues. Synthesized nucleoside analogues 18, 21, 25 and 28 were tested for anti-HIV activity as well as cytotoxicity. Adenine derivatives 18 and 21 showed significant anti-HIV activity up to $100{\mu}M$.

• 대한화장품학회지
• /
• 제23권3호
• /
• pp.82-85
• /
• 1997

To develop an active material for skin darkening, we examined the effect of 300 plants on tyrosinase activity and found only Caesalpinia sappan has an ability to increase tyrosinase activity highly and melanin contents in B-16 melanoma cells. A compound increasing tyrosinase activity and melanin production was isolated from Caesalpinia sappan Lignum. Brazilin was identified as a new active agent. Brazilin increases the tyrosinase activity and malanin production of B-16 melanoma cells. In conclusion, it seems that brazilin cal be used as a new sunless tanning agent.

• Natural Product Sciences
• /
• 제23권3호
• /
• pp.217-221
• /
• 2017

Eleven compounds (1-11) were isolated from the rhizomes of Osmunda japonica, and their structures were elucidated based on $^1H$, $^{13}C-NMR$ and LC-IT-TOF MS data. Of these compounds, all compounds (1 - 11) have been previously reported, although five (6 - 9, 11) have not previously been isolated from this plant. The antioxidant activities of isolated compounds (1 - 11) were measured by DPPH and ABTS assays, and compound 10 showed the high antioxidant activity.

• 한국영양학회:학술대회논문집
• /
• 한국영양학회 2000년도 춘계학술대회 초록
• /
• pp.120-120
• /
• 2000

• Bulletin of the Korean Chemical Society
• /
• 제35권12호
• /
• pp.3502-3508
• /
• 2014

The first synthetic route to 5'-norcarbocyclic C-nucleoside [7-oxa-7,9-dideazadenosine (furo[3,2-d]pyrimidine) and 9-deazaadenosine (pyrrolo[3,2-d]pyrimidine)] phosphonic acids from commercially available 1,3-dihydroxy cyclopentane was described. The key C-C bond formation from sugar to base precursor was performed using Knoevenagel-type condensation from a ketone derivative. Synthesized C-nucleoside phosphonic acids were tested for anti-HIV activity as well as anti-leukemic activity. Compound 26 showed significant anti-leukemic activity.

• 한국식품영양과학회지
• /
• 제37권6호
• /
• pp.810-814
• /
• 2008

수산 가공 폐기물중 하나인 참치 자숙액을 이용하여 천연기능성 소재 개발을 하기 위해 참치 자숙액 에탄올 추출물에 감마선 조사(0, 50 kGy)를 하여 전자공여능을 확인하고, FRAP, UWLA, Rancimat 등을 사용하여 항산화 활성 변화에 관하여 알아보았다. 감마선 조사한 참치 자숙액의 전자공여능 및 hydroxyl 라디칼 소거능 측정 결과 감마선 조사에 의해 각각 16.17% 및 10.38% 증가하였고, 산화안정지수 및 FRAP value 또한 각각 23% 및 26% 증가하였다. ${\beta}$-carotene bleaching assay를 이용하여 항산화지수를 측정한 결과 감마선 조사에 의해 항산화지수가 증가하는 경향을 보였다. 이러한 결과로 미루어 볼 때 참치 자숙액 자체가 가지고 있는 항산화 활성 및 산화안정성을 감마선 조사 기술을 사용하여 증진시켜 식품 및 공중보건산물의 첨가제로서의 이용이 가능할 것이라 사료된다.