• Research in Plant Disease
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• v.16 no.3
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• pp.316-319
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• 2010

The gray mold disease occurred on tuberous roots of yacon in storage facilities in Gangneung, Korea, in March 2010. Symptoms typically appeared as in the form of dark brown discoloration on the surface of tuberous roots and water-soaked brown lesions in cross sections of the affected portions. A total of five isolates of Botrytis sp. were obtained from the symptomatic portions. All isolates on potato-dextrose agar (PDA) produced abundant conidia which were pale brown, one-celled, mostly ellipsoid or ovoid in shape and $8.2{\sim}14.8{\times}6.5{\sim}9.9\;{\mu}m$ in size. Large numbers of round to irregular, smooth, black, hard sclerotia were produced on PDA over time. The optimal temperature for mycelial growth and sclerotia formation of the fungal isolates was $20^{\circ}C$. On the basis of morphological and cultural characteristics, all the fungal isolates were identified as Botrytis cinerea. Pathogenicity test on host plants showed that the fungus could infect not only tuberous roots but also leaves and petioles of yacon. This is the first report on gray mold of yacon (Smallanthus sonchifolius) caused by Botrytis cinerea in Korea.

• The Plant Pathology Journal
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• v.33 no.5
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• pp.488-498
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• 2017

The aim of this study was to identify volatile and agardiffusible antifungal metabolites produced by Bacillus sp. G341 with strong antifungal activity against various phytopathogenic fungi. Strain G341 isolated from four-year-old roots of Korean ginseng with rot symptoms was identified as Bacillus velezensis based on 16S rDNA and gyrA sequences. Strain G341 inhibited mycelial growth of all phytopathogenic fungi tested. In vivo experiment results revealed that n-butanol extract of fermentation broth effectively controlled the development of rice sheath blight, tomato gray mold, tomato late blight, wheat leaf rust, barley powdery mildew, and red pepper anthracnose. Two antifungal compounds were isolated from strain G341 and identified as bacillomycin L and fengycin A by MS/MS analysis. Moreover, volatile compounds emitted from strain G341 were found to be able to inhibit mycelial growth of various phytopathogenic fungi. Based on volatile compound profiles of strain G341 obtained through headspace collection and analysis on GC-MS, dimethylsulfoxide, 1-butanol, and 3-hydroxy-2-butanone (acetoin) were identified. Taken together, these results suggest that B. valezensis G341 can be used as a biocontrol agent for various plant diseases caused by phytopathogenic fungi.

• Research in Plant Disease
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• v.23 no.3
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• pp.256-261
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• 2017

The effects of insecticide and fungicide treatment were investigated to reduce mycotoxin contamination of corn (Zea mays L.) seeds. Deoxynivalenol and zearalenone contents were reduced in the treated seeds, but aflatoxin, ochratoxin A, fumonisin, and T-2 toxin were not effective by chemical treatments. The chemical treatment did not affect the growth of saprophyte, but inhibited the pathogenic fungi such as Fusarium verticillioides, F. graminearum and F. equiseti. Myotoxin contents at different harvesting time were compared. As the harvest time was delayed, both levels of deoxynivalenol and zearalenone and frequency of Fusarium spp. increased. However, the major nutrient contents of corn seeds were not affected by harvesting period. These results show that chemical treatments are necessary to reduce the fungal contamination of corn and harvest without delay is important as well.

• Parasites, Hosts and Diseases
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• v.51 no.6
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• pp.727-733
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• 2013

Despite the existence of effective anthelmintics, parasitic infections remain a major public health problem in Southeast Asia, including Thailand. In rural communities, continuing infection is often reinforced by dietary habits that have a strong cultural basis and by poor personal hygiene and sanitation. This study presents a survey of the prevalence of intestinal parasitic infections among the people in rural Thailand. The community-based cross-sectional study was conducted in villages in Khon Kaen Province, northeastern Thailand, from July to August 2013. A total of 253 stool samples from 102 males and 140 females, aged 2-80 years, were prepared using formalin-ethyl acetate concentration methods and examined using light microscopy. Ninety-four individuals (37.2%) were infected with 1 or more parasite species. Presence of parasitic infection was significantly correlated with gender (P=0.001); nearly half of males in this survey (49.0%) were infected. Older people had a higher prevalence than younger members of the population. The most common parasite found was Opisthorchis viverrini (26.9%), followed by Strongyloides stercoralis (9.5%), Taenia spp. (1.6%), echinostomes (0.4%), and hookworms (0.4%). The prevalence of intestinal protozoa was Blastocystis hominis 1.6%, Entamoeba histolytica 0.8%, Entamoeba coli 0.8%, Balantidium coli 0.4%, Iodamoeba b$\ddot{u}$tschlii 0.4%, and Sarcocystis hominis 0.4%. Co-infections of various helminths and protozoa were present in 15.9% of the people. The present results show that the prevalence of parasitic infections in this region is still high. Proactive education about dietary habits, personal hygiene, and sanitation should be provided to the people in this community to reduce the prevalence of intestinal parasite infections. Moreover, development of policies and programs to control parasites is needed.

• Parasites, Hosts and Diseases
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• v.56 no.1
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• pp.11-19
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• 2018

In Brazil, visceral leishmaniasis (VL) is expanding and becoming urbanized, especially in non-endemic areas such as the State of Rio Grande do Sul. Considering that infected dogs are the main reservoir for zoonotic VL, this study evaluated the prevalence of canine visceral leishmaniasis (CVL) in the metropolitan area of Porto Alegre, a new area of expansion of VL in Brazil. Serum and plasma from 405 asymptomatic dogs from the municipalities of Canoas (n=107), $S\tilde{a}o$ Leopoldo (n=216), and Novo Hamburgo (n=82) were tested for CVL using immunochromatographic ($DPP^{(R)}$) and ELISA $EIE^{(R)}$ assays (2 assays officially adopted by the Brazilian government for the diagnosis of CVL) and real-time PCR to confirm the results. There was no agreement among serological and real-time PCR results, indicating that the Leishmania infection in asymptomatic animals with low parasite load, confirmed by negative parasitological tests (smears and parasite culture), need to be evaluated by molecular methods. The prevalence of LVC in the metropolitan region of Porto Alegre, confirmed by real-time PCR was 4% (5.6% in Canoas and 4.6% in $S\tilde{a}o$ Leopoldo). The use of molecular method is essential for accurate diagnosis of CVL, especially in asymptomatic dogs in non-endemic areas.

• Parasites, Hosts and Diseases
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• v.58 no.3
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• pp.315-319
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• 2020

In November 2019 a 5-month-old mixed-breed rabbit presented to Chungbuk National University Veterinary Teaching Hospital, Cheongju-si, Chungbuk, Republic of Korea (Korea) with symptoms comprising pruritus, crusts on skin, poor appetite and reduced defecation. The rabbit was purchased 2 months prior from a pet shop located in a big market, and that the symptoms were first observed about 2 weeks prior to the hospital visit. Physical examination revealed that the patient had crust formation and alopecia on the nose together with lesions on the digits. A skin scraping test was performed using mineral oil and a high density of mites was observed by microscopy. Each mite showed a round, tortoiselike body with 4 comparatively short pairs of legs. The anus was located at the terminal unlike with suspected pathogen, Notoedres cati. Based on morphological characteristics, we identified the mite as Sarcoptes sp. Ivermectin was administered weekly by subcutaneous injection at a dosage of 0.4 mg/kg, and 4 weeks of follow-up study revealed the patient was fully recovered. And no more mites were detected from the case. This is the first case report of sarcoptic mange in a pet rabbit in Korea.

• Journal of the Korean Wood Science and Technology
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• v.34 no.6
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• pp.61-71
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• 2006

This study was carried out to investigate chemotaxonomical correlation an d the chemical constituents of domestic Quercus sp. leaves. The leaves of Q. mongolica, Q. aliena, Q. serrata, Q. acutissima, Q. dentata and Q. variabilis were collected in the experimental forest of Kangwon National University. The combined extracts were successively fractionated with n -hexane, methylene chloride and ethyl acetate using a separation funnel. A portion of the ethyl acetate and $H_2O$ soluble materials of each species were chromatographed on a Sephadex LH-20 column using various aqueous MeOH and EtOH-hexane as washing solvents. Spectrometric analysis such as NMR and MS, including TLC, were performed to characterize the structures of the isolated compounds. Gallic acid, (+)-catechin, (-)-epicatechin, (+)-gallocatechin, kaempferol, astragalin, astragalin-6"-O-gallate, isoquercitrin, isoquercitrin-6"-O-gallate and myricetin were isolated from Q. mongolic a leaves. Gallic acid, kaempferol and quercetin were characterized from Q. acutissima leaves. Gallic acid, (+)-catechin, (-)-epicatechin, (+)-gallocatechin, (-)-epigallocatechin, kaempferol, quercetin, guajaverin and tamarixin were identified from Q. dentata leaves. Gallic acid, (+)-catechin, (-)-epicatechin, kaempferol, quercitrin, isoquercitrin and myricetin were purified from Q. serrata leaves. Gallic acid, (+)-catechin, astragalin, astragalin-6"-O-gallate and isoquercitrin were isolated from Q. variabilis leaves. Gallic acid was isolated from all the leaves and could be a taxonomic index on Quercus spp..

• Journal of Life Science
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• v.21 no.5
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• pp.684-692
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• 2011

The present study furthered this research by determining the optimal level of inuloprebiotics derived from Korean Jerusalem artichoke to promote growth in broiler chickens. On hatch day, 320 male Ross 308 broilers were randomly allotted to four groups for a 35-day feeding regimen. The groups were a control (no supplementation), diet supplementation with antibiotics (8 ppm avilamycin), supplementation with 200 ppm inuloprebiotics, and supplementation with 250 ppm inuloprebiotics. Body weight and feed intake were comparably high in the two inuloprebiotics groups, and exceeded the values for the control and antibiotics groups. Body weight and feed intake was higher in chickens fed the antibiotics supplemented diet, compared to controls. There were significant differences among treatment groups. Feed conversion ratio during total experimental periods was significantly high in the control group compared to the inuloprebiotics-fed groups, but no significant difference was evident using antibiotics or inuloprebiotics dietary supplementation. Carcass weight, dressing percentage, and weight of breast and thigh muscle were significantly higher for inuloprebiotics-fed chickens, compared with control and antibiotic-fed chickens. Inuloprebiotics concentration was not significant, while antibiotics-fed chickens displayed significantly higher values than control chickens. Abdominal fat was significantly reduced (19.08%-23.30%) and blood immunoglobulin and the weight of the thymus and Bursa of Fabricius were significantly increased in chickens receiving inuloprebiotics-supplemented feed, compared to control and antibiotics fed groups. In the lower intestine, the viable counts of beneficial bacteria (Bifidobacteria and Lactobacillus) were significantly increased and counts of harmful bacteria (Escherichia coli and Salmonella sp.) were significantly decreased in the presence of the inuloprebiotics, compared to control and antibiotic. The present results support 200 ppm as an optimal level of Korean Jerusalem artichoke-derived inuloprebiotics as a dietary supplement to improve growth in broiler chickens.

• Korean Journal of Food Science and Technology
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• v.43 no.2
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• pp.149-155
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• 2011

This study was carried out to develop a method of removing unnecessary sugars and high-molecular weight soluble components from water extract by using various highly porous polymer resins: these resins are widely used as adsorbents for polyphenolic compounds. Each anthocyanin-rich fraction (ARF) that was eluted from column packed with 4 different resins (SEPABEADS SP207, 700, 850 and Diaion HP 20) was obtained from an aqueous extract of the ripe fruits of Rubus coreanus, which is well-known in Korea as "Bok-bun-ja". Among the above mentioned resins, Diaion HP20 had the highest efficacy and provided maximum yield of the ARF. The ARF eluted from the column packed with HP 20 exhibited the strongest antioxidant activity in vitro. Bioactive phytochemicals extracted from Rubus coreanus were investigated using the on-line HPLC-$ABTS^{{\cdot}+}$ system, and the resulting 6 peaks were identified as radical-scavenging components. By using liquid chromatography-mass spectrometry, 5 peaks were obtained, and these were identified as cyanidin-3-sambubioside, cyanidin-3-glucoside, cyanidin-3-xylosylrutinoside, cyanidin-3-rutinoside and pelargonidin-3-rutinoside. These results indicate that the use of appropriate porous resin (Diaion HP 20) leads to an increase in the yield of bioactive components and enhancement of their biological properties.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.37 no.5
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• pp.423-432
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• 2004

In coastal area of Inchon, dredging and the disposal of dredged material for sea-wall construction and reclamation have increased in recent years. These activities may impact the benthic environment and result in changes in benthic communities, but little information is available on the extent and direction of these changes. We investigated whether there have been changes in the dominant macrobenthic species and benthic community over the last decade, and explored the relationship between environmental variables and spatial patterns of macrobenthic community structure. We sampled macrobenthos and recorded environmental variables in the coastal habitats of Inchon in March and June 2004. In total, 212 macrobenthic species were recorded during this study, predominately crustaceans $(34{\%})$, mollusks $(32{\%})$ and polychaetes $(21{\%})$. The mean density of macrobenthos was $1,393\;ind./m^{2}$.The most abundant species was Amphioplus japonicus $(20.5{\%})$, followed by Heteromastus filiformis $(14.4{\%})$, Theora fragilis $(8.2{\%})$ and Ampharete sp. $(4.0{\%})$. Over the past decade the dominant macrobenthic species in this area shifted. Multivariate analysis (multidimensional scaling) revealed significant differences in community structure among three regions: the middle part of the sampling area (B), site 8 (C) and other sites (A). Mean density varied significantly among the three regions, but no differences in the number of species and diversity (H') were observed. The distribution of the macrobenthic community was affected by environmental variables such as percentage sand content and sediment kurtosis. Species that were important in different areas included A. japonicus in region A, Raeta puchella in region B and T. fragilis in region C. The important species in regions B and C were filter-feeding bivalves, and the abundance of these species may be related to the increase in percentage sand content. We suggest that the sediment composition (percentage sand content) may be an important factor in determining the dominant species and structure of the macrobenthic communities in coastal Inchon. Long-term monitoring programs are necessary to understand ongoing changes in the benthic communities of this area.