• The Korean Journal of Pesticide Science
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• v.16 no.3
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• pp.209-216
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• 2012

In the continued research on natural fungicides for control of plant diseases by using plant-derived products, we found that Spatholobus suberectus Dunn had a strong fungicidal activity against several plant pathogens. S. suberectus (1 kg) was extracted with 80% aqueous MeOH and then the concentrated extract was partitioned with n-hexane, EtOAc, n-BuOH and $H_2O$ successively. The four layers were tested their disease contron efficacies against 6 plant diseases such as rice blast (RCB), rice sheath blight (RSB), tomato grey mold (TGM), tomato late blight (TLB), wheat leaf rust (WLR), and barley powdery mildew (BPM). The EtOAc fraction was highly active showing over 80% control against RCB, TGM, TLB, and BPM. By using silica gel chromatography, preparative TLC and HPLC, six compounds that were expected to have antifungal activity were separated. Their chemical structures were identified as ethanone, hydroxytyrosol, epicatechin, procyanidin B2, dimethoxy daizein and formononetin by ESI-MS, $^1H$-NMR, $^{13}C$-NMR, and 2D-NMR spectroscopic analyses. The chemicals except epicatechin were first reported in S. suberectus. Study on in vitro and in vivo antifungal activities of the isolated compounds is in progress.

• Journal of fish pathology
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• v.22 no.3
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• pp.317-326
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• 2009

This study has shown the screening of anti-bacterial activity of three Indian medicinal plant choloroform : methanol (50:50) solvent leaf extracts (i.e. Azadirachta indica, Ocimum sanctum, and Curcuma longa) with different concentrations (10, 5, 2.5, 1.25, 0.625, 0.312, and 0.156 mg/ml) under in vitro conditions against fish pathogenic bacteria, Aeromonas hydrophila, Streptococcus iniae, Vibrio harveyi, V. anguillarum, and Edwardsiella tarda isolated from olive flounder farms, Jeju Island, South Korea. The anti-microbial activity of the A. indica and O. sanctum extracts yielded the zones of growth inhibition (ZI) was 3 and 1mm against A. hydrophila at concentration of 0.156 mg/ml when compared to that of tetracycline standard (3 mm). At highest concentration (10 mg/ml) of A. indica, O. sanctum, and C. longa, high inhibition was 9, 7, and 6 mm when compared to that of tetracycline (11 mm) against A. hydrophila. The minimum inhibitory concentration (MIC) of A. indica, O. sanctum, and C. longa at 0.156 mg/ml that yield 9, 10, and 13 CFU/ml for A. hydrophila, 16, 22, and 25 CFU/ml for S. iniae and 18, 22, and 23 CFU/ml for E. tarda compared to the tetracycline. At highest concentration (10 mg/ml) of the three extracts was better inhibiting the growth of A. hydrophila, S. iniae and E. tarda. A. indica, O. sanctum, and C. longa were determined to the potential antioxidant activityon the basis of their scavenging activity of the stable 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical. A. indica extract was 0.625 mg/ml which indicated that the strong anti-oxidant activity. However, O. sanctum and C. longa extracts showed weak anti-oxidant activity at this concentration. Hence, in vitro assay among the pathogens, A. hydropila is better inhibitory activity of the extracts. It is evident that the Indian medicinal plants extracts were subjected to its effectiveness against A. hydrophila, S. iniae, and E.tarda at low concentrations. The obtained results in the present study suggested that the Indian plant extracts is a prevention tools for Korean olive flounder aquaculture pathogens and its need further advance investigation.

• Korean Journal of Food Science and Technology
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• v.35 no.5
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• pp.975-979
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• 2003

Perilla leaves cultivated in greenhouses (Jan., May) and in the fields (Aug.) of Geumsan province were investigated for their extract yields and physiological functionalities. The yield was highest in 30% ethanol extracts of the August perilla leaves. The highest fibrinolytic activity (8.2 U) was observed in 30% ethanol extracts of the May perilla leaves, while the HMG-CoA reductase inhibition level, which is related to the inhibition of cholesterol biosynthesis, was 83% in water extracts of the August perilla leaves. Anti-hypertensive ACE inhibitory activity was 64.5% in the water extracts of the January perilla leaves, and antioxidative electron donating ability was the highest (69%) in 30% ethanol extracts of the August perilla leaves. Elastase inhibitory activity, which is related to the inhibition of skin aging, was highest (47.5%) in 30% ethanol extracts of the May perilla leaves. However, SOD-like activity, nitrite scavenging activity, and tyrosinase inhibitory activity were not detected were very weak in all samples.

• Korean journal of applied entomology
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• v.44 no.4 s.141
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• pp.257-264
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• 2005

In order to establish the successive rearing system brush-footed butterflies (Lepidoptera : Nymphalidae) were reared in a room. Artificial diets were developed for a year-round rearing. Bu-diet was best to rear these butterflies among 3 kinds of diet used. The freeze-dried host plant leaf powder in diet was better than heat-dried one $(60^{\circ}C)$ in the growth of larvae. The rearing results were best in the diet C/N ratio was 1:1. The 24-hrs old eggs could be stored for 5 days at $15^{\circ}C$ or for 3 days at $5^{\circ}C$ and showed 75% of hatchability. On the other hand, pupae could be stored for maximum 15 days at $15^{\circ}C$ because the emergence of abnormal adults appeared much more as the cold storage period got longer. And the adult was able to be stored until 60 days at refrigerator without relation of nectar-sucking period before cold-storage and storage temperature. Also a simple artificial ovipositing kit was devised by ${\Phi}9$ cm of petri-dish and a female oviposited $278{\pm}27$ of eggs with adding the ether extract of host plant to this kit. The systematic successive rearing method of brush-footed butterflies in a room was completed.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.4
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• pp.509-516
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• 2011

The antioxidant and anticancer activities of leaves and stems from Gaeddongssuk (Artemisia annua L.) were investigated. The leaves and stems were extracted with water and 80% ethanol, respectively. The antioxidant and growth inhibition activities toward cancer cells by the 4 kinds of extracts were tested. In addition, phenolic compounds from A. annua were identified through quantitative analysis using HPLC. Antioxidant activities significantly increased in a does-dependent manner, and those of water and ethanol extracts of the leaves were stronger than those of the stems. Growth inhibition activities of the leaf extracts on HeLa and AGS cells were higher than those of the stem extracts. In particular, the ethanol extract of the leaves had growth inhibition activities of 61.07% and 57.24% against HeLa and AGS cells, at the concentration of $500\;{\mu}g$/mL, respectively, which were the highest among all the extracts. Phenolic acid and catechin contents of the A. annua extracts as determined by HPLC were higher in the leaves than in the stems. Flavonols were identified only in the leaves. The data suggest that the antioxidant and anticancer activities of A. annua extracts were due to phenolic compounds as well as unknown biological compounds in A. annua.

• Korean Journal of Plant Resources
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• v.30 no.4
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• pp.343-351
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• 2017

Plant extracts were screened for antifungal activity against major plant pathogens, Botrytis sp., Collectotrichum sp., Alternaria sp. and Cylindrocarpon sp. using 96-well microdilution method. Among the 662 methanol extracts from 401 plant species, 36 extracts showed complete inhibition of spore germination against at least one of four pathogenic fungi. Extracts of Morus alba twig and Sophora flavescens root showed minimum inhibition concentration (MIC) at $1,250{\mu}g/ml$ against Botrytis sp.. Extracts of Chloranthus japonicus root showed MIC at $1,250{\mu}g/ml$ against Collectotrichum sp.. Extracts of Glycyrrhiza uralensis aerial part, Inula helenium root and Menispermum dauricum root showed MIC between 625 and $1,250{\mu}g/ml$ against Alternaria sp.. G. uralensis aerial part and I. helenium root showed MIC at $1,250{\mu}g/ml$ against Cylindrocarpon sp.. Specifically, the extracts of Agrimonia pilosa root, Angelica tenuissima root, Asarum sieboldii root, Campsis grandifolia leaf and twig, Cnidium officinale root, Dictamnus dasycarpus root, G. uralensis aerial part, I. helenium root and M. alba twig completely inhibited spore germination at lower than $5,000{\mu}g/ml$ against all of four pathogenic fungi. Two methanol extracts from G. uralensis aerial part and M. alba twig may used as a candidate to develop into effective disease management materials in plant cultivation.

• Journal of Life Science
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• v.22 no.9
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• pp.1254-1260
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• 2012

The moringa (Moringa oleifera Lam.) plant is used both as food and an anti-allergic agent. In this study, we investigated skin protection effects of methanol extracts from the root, seed, fruit, and leaves of moringa in HaCaT keratinocyte cells. To investigate the pharmacological potential of various moringa extracts on TNF-${\alpha}$-induced collagen degradation in HaCaT cells, we measured the activity of matrix metallopeptidase-9,2 (MMP-9,2) by zymography analysis. Our results showed that all the moringa extracts inhibit the TNF-${\alpha}$-induced enzyme activity of MMP-9. In particular, moringa root extracts significantly suppressed MMP-9 and MMP-2 in a dose-dependent manner. Next, to investigate the anti-inflammation effect of the moringa extracts, we examined cyclooxygenase-2 (COX-2), inducible nitric oxide synthase (iNOS), and interleukin-6 (IL-6) expression of the extracts. The results showed that both the root extracts and the seed extracts decreased the TNF-${\alpha}$-induced expression of COX-2. In addition, the root and leaf extracts reduced the expression of IL-6. However, none of the moringa extracts affected the expression of iNOS. The results suggest that moringa root extracts down-regulate MMP-9, COX-2, and IL-6 and that the root extracts offer superior skin protection effects compared with other extracts of moringa in HaCaT cells.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.46 no.6
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• pp.439-442
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• 2001

This study has been conducted from April 25, 1999 to June 25, 1999 in Jeju Province in order to determine the influence of seeding date on growth, yield and chemical composition of Kenaf (Hibiscus cannabinus L.) Delaying the seeding date from April 25 to June 25 decreased the plant height of Kenaf from 278.5 cm to 205.7 cm. As for the number of leaves, number of withering leaves, number of branches, and stem diameter decreased as the seeding date was delayed. As the seeding date was delayed, fresh forage yield decreased from 98.5MT/㏊ to 45.9MT/㏊, dry matter yield from 20.7MT/㏊ to 8.2MT/㏊, crude protein (CP) yield from 2.9MT/ha to 1.3MT/ha and total digestible nutrients (TDN) yield form 1l.6MT/㏊ to 5MT/㏊. However, both leaf yield and stem yield were nearly the same tendency. Delaying the seeding date from April 25 to June 25 increased crude protein contents of leaves from 21.5％ to 24.4％, crude fat contents from 5.2％ to 6.1％, nitrogen free extract (NFE) contents form 39.9％ to 41.2％ and TDN contents from 64.3％ to 69.7％. However, delaying seeding date decreased crude fiber contents from 20.8％ to 17.5％, and crude ash contents from 7.9％ to 7.0％. Based on the these findings, optimum seeding date for forage production of Kenaf seems to be about 25 April in atmospheric phenomena and volcanic ash soils of Jeju island.

• Research in Plant Disease
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• v.12 no.2
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• pp.129-133
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• 2006

A bacterial disease of small red bean (Phaseolus angularis) was observed on field-grown plants in Suwon in year 2003. Leaf symptoms initially appeared as water-soaked spots that gradually enlarged, became flaccid and necrotic and were often bordered by a small zone of lemon yellow tissue. In the case of severe infection, dead leaves were defoliated. Pod symptoms consisted of the lesions that were generally circular, slightly sunken and dark reddish brown. Isolation made from diseased leaves on yeast extract dextrose calcium carbonate agar yielded nearly pure cultures of a yellow-pigmented bacterium typical of a xanthomonad. Three bacterial strains were purified and used for further tests. Pathogenicity of strains was confirmed on 3-week-old small red bean plants sprayed with bacterial suspensions containing $10^8 cfu/ml$ of phosphate buffered saline. The representative Xanthomonas strains isolated from small red bean were compared with X. axonopodis pv. phaseoli and X. axonopodis pv. phaseoli var. fuscans type strains for fatty acid profiles, biochemical tests and metabolic fingerprints using Biolog GN2 microplate, showing that all outcomes were indistinguishable between our isolates and reference strains. Two of three strains produced a melanin-like brown pigment extracellularly on King's medium B agar. These results suggest that this new small red bean disease observed in Suwon is bacterial fuscous blight caused by X. axonopodis pv. phaseoli and X. axonopodis pv. phaseoli var. fuscans.

• Research in Plant Disease
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• v.12 no.2
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• pp.134-138
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• 2006

A new bacterial disease of broccoli (Brassica oleracea var. italica) was observed on field-grown plants in Pyungchang during 2003 and 2004. Seedling infections first appeared as a blackening along the margins of the cotyledon. Cotyledon shriveled and dropped off. Infected seedlings were stunted and yellowed and eventually died. The disease was easily recognized by the presence of yellow, V-shaped, or U-shaped areas extending inward from margin of the leaf. As the disease progressed, the yellow lesions turned brown and the tissues died. Isolations made from diseased leaves on yeast extract dextrose calcium carbonate agar yielded nearly pure cultures of a yellow-pigmented bacterium typical of a xanthomonad. Two bacterial strains were purified and used for further tests. Pathogenicity of strains was confirmed on 3-week-old crucifer (cabbage, Chinese cabbage, kale, radish and broccoli) plants cut by scissors with bacterial suspensions containing $10^8 cfu/ml$ of phosphate buffered saline. The Biolog and fatty acid analyses and 16S rDNA sequencing of two strains (SL4797 and SL4800) from broccoli black rot showed that they could be identified as X. campestris pv. campestris because of their high similarity to the tester strain (X. campestris pv. campestris NCPPB528) with a match probability of 100%. This is the first report of black rot of broccoli in Korea.