• Mycobiology
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• v.29 no.3
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• pp.176-178
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• 2001

A soft rot of fruits caused by Rhizopus stolonifer occurred on cherry tomato in Jinju City Agricultural Products Wholesale Market, Korea. The disease infection usually started from wounding after cracking of fruits. At first, the lesions started with water soaked and were rapidly softened and diseased lesion gradually expanded. The mycelia grew vigorously on the surface of fruits and formed stolons. Colonies on potato dextrose agar at $25^{\circ}C$ were white cottony at first, becoming heavily speckled by the presence of sporangia and the browinish black, and spreading rapidly by means of stolons fired at various points to the substrate by rhizoids. Sporangia were $82.7{\times}196.7{\mu}m$ in size and globose or sub-globose with somewhat flattened base. The color of sporangia was white at first and then turned black with many spores, and never overhanging. Sporangiophores were $2.6{\sim}5.8{\times}12.3{\sim}24.2{\mu}m$ in width, smooth-walled, non-septate, tight brown, simple, long, arising in groups of $3{\sim}5$ from stolons opposite rhizoids. Sporangiospores were $8.2{\sim}18.8{\mu}m$ long, irregular, round, oval, elongate, angular, and browinish-black streaked. Columella was $64.1{\times}136.3{\mu}m$. brownish gray, and umberella-shaped when dehisced. The causal organism was identified to be R. stolonifer. This is the first report of Rhizopus soft rot on cherry tomato caused by R. stolonifer in Korea.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2002.08a
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• pp.64-71
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• 2002

Rice(Oryza stiva L.) is a major cereal food providing nourishment to over half of the world's populations and was considered only as a source of energy. However, The recent many researches have been made to suggest that rice may relate to prevention chronic disease and health-promoting properties such as postprandial glucose response, hypocholesterolemic effect and blood pressure-lowering effect. There has been numerous observation supporting that rice has hypocholesterolemic effect. Rice, rice bran, rice bran oil and unsaponifiable matter of rice bran oil reduced plasma cholesterol in rat, hamster as well as human. Components of rice showing hypocholesterolemic effect include dietary fiber(hemicellulose, phytic acid). protein, ${\gamma}$-oryzanol, $\beta$-sitosterol, and tocotrienols. Crapo et al has been studied that the effect of various of starchy foods on the postprandial blood glucose and insulin responses in healthy and diabetic humans. The results showed that rice had lower blood glucose and insulin responses compared to potato, bread and dextrose. The different physical forms in the same starch also produce the different postprandial glucose and insulin responses. In recent years, several studies have shown that some components of rice have potent antioxidant activity against Fe$^{2+}$ -ascorbate induced lipid peroxidation in rat liver microsomal membranes. Cell culture and animal studies have shown that some components of rice have inhibitory effect on the growth and proliferation of several types of human cancer cell. It was also reported that the methanol extract of brown rice has antimutagenic activity against various mutagens. In addition, the pepsine hydrolysate from rice protein is reported to inhibit angiotensin converting enzyme activity. GABA (${\gamma}$ - aminobutyric acid) and GABA enriched rice germ is also effective for lowering blood pressure and triglyceride levels.s.

• The Korean Journal of Mycology
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• v.33 no.1
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• pp.35-37
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• 2005

Anthracnose symptoms on Spiraea prunifolia were observed around the residential area of Dongbumyon, Geoje City, Gyeongnam Province, Korea in 2002 and 2003. Typical symptoms of the disease were dark red spot on the leaves and black spot on the stem. The pathogen formed gray to dark gray colony on potato dextrose agar. Conidia were single celled, color, ovoid or oblong in shape and $6{\sim}12\;{\times}\;3{\sim}5\;{\mu}m$ in size. Seta were dark brown in color, cone-shaped in shape and $23{\sim}42\;{\times}\;2{\sim}4\;{\mu}m$ in size. The optimum temperature for growth of the isolate was about $25{\sim}30^{\circ}C$. On the basis of mycological characteristics and pathogenicity test on host plants, the fungus was identified as Colletotrichum gloeosporioides. This is the first report on the anthracnose of S. prunifolia caused by C. gloeosporioides in Korea.

• Korean Journal of Community Nutrition
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• v.13 no.3
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• pp.439-452
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• 2008

This study was conducted to identify major dietary patterns of generally healthy Korean middle-aged women and to examine associations of the dietary patterns with socio-demographic, psychological, and physical characteristics. Data were drawn from the 2001 Korean National Health and Nutrition Examination Survey (KNHANES), which is an ongoing national surveillance system. Healthy female subjects aged 40-64 years and provided the health interview examination and food frequency questionnaire (FFQ) data were included. We conducted factor analysis based on daily mean intake frequency of 26 food groups and identified 3 major dietary patterns, healthy, convenient, and alcohol-animal. The healthy pattern was characterized by higher intakes of fish, seafood, poultry, mushroom, seaweed, vegetable, tomato, potato, and fruit, the convenient pattern by processed meat and fish, ramen, noodle and rice cake, sweet snack, egg, bread, and fast food, and the alcohol-animal pattern by alcohol, poultry, meat, and fish. The healthy pattern was significantly related with higher socio-economic status, more stable family structure, healthier mentality, and sounder status of anthropometric and biochemical variables. Those with higher factor scores for the convenience pattern were found to be younger and having higher socio-economic status, higher subjective levels of health, and lower subjective levels of worry on health. Several physical characteristics significantly improved as the levels of the convenience pattern increased. The alcohol-animal pattern was significantly associated with several socio-demographic characteristics including a low education level, a young age, a small family size, and blue-collar jobs. Public health policy makers can utilize the study findings to select prior target populations with higher needs and to tailor dietary behavioral messages to lower chronic disease risks among Korean middle-aged women.

• Journal of Microbiology and Biotechnology
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• v.23 no.1
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• pp.29-35
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• 2013

A Nodulisporium sp. (Hypoxylon sp.) has been isolated as an endophyte of Thelypteris angustifolia (Broadleaf Leaf Maiden Fern) in a rainforest region of Central America. It has been identified both on the basis of its morphological characteristics and by scanning electron microscopy as well as ITS sequence analysis. The endophyte produces volatile organic compounds (VOCs) that have both fuel (mycodiesel) and use for biological control of plant disease. When grown on potato dextrose agar, the organism uniquely produces a series of ketones, including acetone; 2-pentanone; 3-hexanone, 4-methyl; 3-hexanone, 2,4-dimethyl; 2-hexanone, 4-methyl, and 5-hepten, 2-one and these account for about 25% of the total VOCs. The most abundant identified VOC was 1,8 cineole, which is commonly detected in this group of organisms. Other prominent VOCs produced by this endophyte include 1-butanol, 2-methyl, and phenylethanol alcohol. Moreover, of interest was the presence of cyclohexane, propyl, which is a common ingredient of diesel fuel. Furthermore, the VOCs of this isolate of Nodulisporium sp. were selectively active against a number of plant pathogens, and upon a 24 h exposure caused death to Phytophthora palmivora, Rhizoctonia solani, and Sclerotinia sclerotiorum and 100% inhibition to Phytophthora cinnamomi with only slight to no inhibition of the other pathogens that were tested. From this work, it is becoming increasingly apparent that each isolate of this endophytic Nodulisporium spp., including the Daldina sp. and Hypoxylon spp. teleomorphs, seems to produce its own unique set of VOCs.

• The Plant Pathology Journal
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• v.18 no.6
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• pp.333-337
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• 2002

Bacteriophage of Xanthomonas axonopodis pv. citri, a causal agent of citrus canker disease, was studied for its cultural characteristics. The relative efficiency of plat-ing (EOP) of 11 phages used to 13 strains off, axonopodis pv. citri tested ranged from 0.8 to 1, indicating that the phages are homogeneous. Homogeneity of the phages suggests that citrusphage belongs to a single group CPK as reported in a previous study. Typical one-step growth of a phage P5 selected from the citrusphages was observed. The EOP of the P5 was dependent upon the media, pH, and temperature. It was observed that multiplication of the phage cultured in Wakimotos potato semisynthetic media at $25^{\circ}C$ was more effective than that in other temperatures, regardless of the bacterial strains and media used. It was observed that pH 6.5 is optimal for multiplication of the phage. In comparison of the EOP among citrusphages $CP_1$, $CP_2$, and P5, multiplicative characteristic of phage P5 in the bacteria on time-course was similar with that of phage $CP_1$. Thus, it was concluded that citrusphage group CPK from Korea is $CP_1$ based on host specificity of the phage as described in a previous study, homogeneity, and its multiplication pattern.

• Research in Plant Disease
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• v.18 no.2
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• pp.139-141
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• 2012

Stem rot symptoms of common bean occurred sporadically in Jinju, Korea. The typical symptom included water-soaking on the main stem, rotting, wilting, and blighting, which eventually leads to death of the plant. The sclerotia, white to brown, spherical with size of 1-3 mm, formed over lesions and surface soil line. The optimum temperature for mycelial growth and sclerotia formation was $30^{\circ}C$ on potato dextrose agar (PDA). The typical clamp connections were observed in the hyphae of the fungus grown on PDA. Mycological characteristics and pathogenicity to host plants indicated that the fungus was Sclerotium rolfsii Saccardo. This is the first report of stem rot on common bean caused by S. rolfsii in Korea.

• Research in Plant Disease
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• v.14 no.1
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• pp.61-63
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• 2008

Anthracnose of blueberry (Vaccinium spp.) caused by Colletotrichum gloeosporioides was observed in the exhibition orchard of Gyeongsangnam-do Agricultural Research and Extension Services in Korea, 2007. The typical symptoms were initially water-soaked lesions and then rotten on fruits, the infected fruits were dropped but some of them were hunged and mummified. The pathogenic fungus grown on potato dextrose agar showed greyish to dark gray color. Conidia were straight, cylindrical apex obtuse in shape and $10{\sim}20{\times}3{\sim}5\;{\mu}m$ in size. Appressoria were brown in color, clavate or ovate in shape and $6{\sim}18{\times}4{\sim}12\;{\mu}m$ in size. Optimum temperature for mycelial growth was $25{\sim}30^{\circ}C$. On the basis of mycological characteristics and pathogenicity test on host plants, the fungus was identified as Colletotrichum gloeosporioides (Penz.) Penz. & Sacc.. This is the first report on the anthracnose of blueberry (Vaccinium spp.) caused by C. gloeosporioides in Korea.

• Research in Plant Disease
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• v.12 no.2
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• pp.119-121
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• 2006

Anthracnose of pomegranate (Punica granatum) caused by Colletotrichum acutatum was observed in the exhibition field at Hamyang-gun, Gyeongsangnam-do Agricultural Research and Extension Services, and in farmer's orchard at Gaheo-myon, Hapcheon-gun, Gyeongnam province, Korea. The pathogen generally attacks on the fruits and induces dark lesion and rotting. The infected fruits were mostly dropped or mummified. The color of colonies of the pathogenic fungus grown on potato dextrose agar was pinkish gray. Conidia were fusiform in shape and was $8{\sim}16{\times}3{\sim}4{\mu}m$ in size. Appressoria were pale to dark brown in color, clavate in shape and was $8{\sim}12{\times}4{\sim}6{\mu}m$ in size. Optimum temperature for mycelial growth was $25^{\circ}C$. Pathogenicity of the causal organism was proved according to Koch's postulate. On the basis of mycological characteristics and pathogenicity test on fruit, the fungus was identified as Colletotrichum acutatum. This is the first report on the anthracnose of pomegranate caused by C. acutatum in Korea.

• The Plant Pathology Journal
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• v.35 no.1
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• pp.77-83
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• 2019

Chlorine dioxide ($ClO_2$) can be used as an alternative disinfectant for controlling fungal contamination during postharvest storage. In this study, we tested the in vitro and in vivo inhibitory effects of gaseous $ClO_2$ against Diaporthe batatas SP-d1, the causal agent of sweetpotato dry rot. In in vitro tests, spore suspensions of SP-d1 spread on acidified potato dextrose agar were treated with various $ClO_2$ concentrations (1-20 ppm) for 0-60 min. Fungal growth was significantly inhibited at 1 ppm of $ClO_2$ treatment for 30 min, and completely inhibited at 20 ppm. In in vivo tests, spore suspensions were drop-inoculated onto sweetpotato slices, followed by $ClO_2$ treatment with different concentrations and durations. Lesion diameters were not significantly different between the tested $ClO_2$ concentrations; however, lesion diameters significantly decreased upon increasing the exposure time. Similarly, fungal populations decreased at the tested $ClO_2$ concentrations over time. However, the sliced tissue itself hardened after 60-min $ClO_2$ treatments, especially at 20 ppm of $ClO_2$. When sweetpotato roots were dip-inoculated in spore suspensions for 10 min prior to treatment with 20 and 40 ppm of $ClO_2$ for 0-60 min, fungal populations decreased with increasing $ClO_2$ concentrations. Taken together, these results showed that gaseous $ClO_2$ could significantly inhibit D. batatas growth and dry rot development in sweetpotato. Overall, gaseous $ClO_2$ could be used to control this fungal disease during the postharvest storage of sweetpotato.