• Mycobiology
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• v.46 no.2
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• pp.154-158
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• 2018

Bitter rot caused by the fungal genus Colletotrichum is a well-known, common disease of apple and causes significant yield loss. In 2013, six fungal strains were isolated from Fuji apple fruits exhibiting symptoms of bitter rot from Andong, Korea. These strains were identified as Colletotrichum fructicola and C. siamense based on morphological characteristics and multilocus sequence analysis of the internal transcribed spacer rDNA, actin, calmodulin, chitin synthase, and glyceraldehyde-3-phosphate dehydrogenase Pathogenicity tests confirmed the involvement of C. fructicola and C. siamense in the development of disease symptoms on apple fruits. This is the first report of C. fructicola and C. siamense causing bitter rot on apple fruit in Korea.

• Mycobiology
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• v.48 no.1
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• pp.75-79
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• 2020

Anthracnose is one of the major problems for cultivating many crops, including vegetables, fruits, and trees. It is a continual threat for fruits grower worldwide. Colletotrichum fructicola was isolated from Shine Muscat berries showing typical anthracnose symptom in Korea. It was identified as C. fructicola based on morphology, pathological signs and concatenated sequences of internal transcribed spacer region of rDNA, glyceraldehyde-3-phosphate dehydrogenase, β-tubulin-2, chitin synthase-1, calmodulin, and the Apn2-Mat1-2 intergenic spacer and partial mating type (Mat1-2) gene. To the best of our knowledge, this is the first report first report of anthracnose of Shine Muscat caused by C. fructicola in Korea.

• The Korean Journal of Mycology
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• v.52 no.2
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• pp.135-143
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• 2024

Lindera obtusiloba Blume, a shrub prevalent in the understory vegetation of the deciduous forests in East Asia and Korea, is known for its pharmacological properties, including antioxidant, anti-allergic, and anti-inflammatory activities. Endophytic fungi were isolated from surface-sterilized twigs and leaves of L. obtusiloba collected from Samcheok-si and Jecheon-si in Korea. The fungal strains were identified based on their morphological characteristics and molecular analyses using DNA markers such as internal transcribed spacer, large subunit rDNA, β-tubulin, chitin synthase, and glyceraldehyde-3-phosphate dehydrogenase. Here, we report two new records of endophytic fungi isolated from L. obtusiloba in Korea: Colletotrichum citricola and Valsa ceratophora. These results enhance our understanding of the diversity of endophytic fungi in L. obtusiloba and contribute to enhancing our knowledge of fungal biodiversity in Korea.

• The Korean Journal of Mycology
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• v.52 no.2
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• pp.109-114
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• 2024

Anthracnose fruit rot (AFR) has been observed in greenhouses during the harvesting period in the Chungnam Province of South Korea. Fruits infected inside the greenhouse show black or brown spots, orange conidial masses and in some areas of the infected parts, white fungal growths are visible. The size of these spots gradually expands, leading to the necrosis of the fruits and flowers. Three isolates were obtained from infected fruits and identified as strains of the Colletotrichum acutatum species complex based on morphological characteristics. Multilocus sequence analysis of actin, chitin synthase, glyceraldehyde-3-phosphate dehydrogenase genes, and internal transcribed spacer rDNA regions revealed that the isolates belong to a monophyletic group with the type strain of C. nymphaeae. This is the first time C. nymphaeae has been confirmed in strawberry fruit in Korea.

• The Korean Journal of Pesticide Science
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• v.6 no.2
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• pp.105-109
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• 2002

Synthetic method of a new benzoylphenylurea insecticide, DBI-3204 [1-(2,6-Difluorobenzoyl)-3-(3,5-bistrifluoromethyl-2-chlorophenyl) urea] was established for manufactural production; 2,6-Difluorobenzoylisocyanate was synthesized by the reaction of 2,6-difluorobenzamide with oxalylchloride in 95% yields, the reaction of 3,5-bis(trifluoromethyl)aniline with N-chlorosuccinimde gave 3,5-bis (trifluoromethyl)-2-chloroaniline in 92% yields, and DBI-3204 was got from 2,6-difluorobenzoylisocyanate and 3,5-bis(trifluoromethyl)-2-chloroaniline in 90% yields. All the process was simplified by using the same reaction solvent, carbontetrachloride.

• Journal of Chitin and Chitosan
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• v.22 no.3
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• pp.185-193
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• 2017

Red tide Heterosigma akashiwo (H. akashiwo), a microscopic alga of the class Raphidophyceae, causes extensive damage to all marine ecosystems. It is essential to reduce the damage to marine ecosystems for them to be used as a resource. In this study, we used organic solvent fractionation to obtain an ethyl acetate-methanol extract from H. akashiwo (HAEM80) and then evaluated its anti-inflammatory activity in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells and a zebrafish model. HAME80 markedly inhibited the production of nitric oxide (NO) and prostaglandin $E_2$ ($PGE_2$). It also down-regulated the protein expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) and decreased the secretion of interleukin-$1{\beta}$ ($IL-1{\beta}$) in LPS-stimulated RAW 264.7 cells. HAME80 reduced yolk edema and improved the survival rate of LPS-stimulated zebrafish embryos; in addition, the extract significantly reduced the production of ROS and NO and attenuated cell death in this model. Gas chromatography-mass spectrometry (GC-MS) of the extract was used to confirm the identity of peaks 1-20. Taken together, our data suggest that H. akashiwo is a beneficial anti-inflammatory agent.

• The Korean Journal of Mycology
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• v.50 no.3
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• pp.235-241
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• 2022

Anthracnose crown rot (ACR) has been observed in greenhouses during the nursery and harvest seasons in Gangwon Province, Korea. Infected plants showed black leaf spot, dark sunken pink conidial masses on petioles, wilting, and eventually death. Five isolates were obtained from the lesions of strawberry plants and were identified as a Colletotrichum gloeosporioides species complex based on their cultural and morphological characteristics. Multilocus sequence analysis of actin, calmodulin, chitin synthase, glyceraldehyde-3-phophate dehydrogenase genes, and internal transcribed spacer rDNA regions showed that the isolates formed a monophyletic group with the type strain of C. siamense. Pathogenicity tests were performed on the isolate, and Koch's postulates were performed to verify the relationship between Colletotrichum sp. and the strawberry plant variety Seolhyang. The isolate was pathogenic to strawberry plants, which exhibited typical ACR symptoms. Based on morphological characteristics, pathogenicity, and DNA sequence analyses, the fungus isolated in Korea was identified as C. siamense. This is first time C. siamense has been confirmed in ever-bearing strawberry varieties in Korea.

• Research in Plant Disease
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• v.27 no.2
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• pp.70-75
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• 2021

The abnormal brown sunken lesions were observed on cv. RubyS apple fruits in an orchard located in Gunwi, Gyeongbuk province, Korea. The primary observed symptoms such as small round sunken lesions and small black dots on the symptomatic area were different from the reported apple diseases. The affected apple fruits were sampled and subjected to isolation of the causal agent. Cultural and morphological characteristics of isolated fungal strain, designated KNUF-20GWA4, were similar to that of Colletotrichum spp. Based on multilocus sequence analyses using internal transcribed spacer regions and partial sequences of β-tubulin, glyceraldehyde-3-phosphate dehydrogenase, chitin synthase, and actin genes, strain KNUF-20GWA4 showed 99.2-100% similarities with C. aenigma ICMP 18608 and the isolate clustered together with several other strains of this species in the phylogenetic tree. To our knowledge, this is the first report of bitter rot on apple fruits caused by C. aenigma.

• Journal of Chitin and Chitosan
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• v.23 no.4
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• pp.262-266
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• 2018

Even though the saps have been consumed as beverage in Korea, however a little research has been conducted on the chemical composition. We determined free sugars, mineral in the sap from Juglans mandshurica Maxim. collected from BongHwa region. The contents of glucose, sucrose, and fructose in the sap from J. mandshurica were 0.15, 2.73, and 0.09%, respectively. The prominent minerals in the sap from J. mandshurica were calcium and potassium. The contents of Ca, K, Mg, Fe, and Mn of sap from J. mandshurica were 0.61, 0.57, 0.12, 0.002, and 0.014 ppm, respectively. The sap from J. mandshurica show inhibitory effect on elastase. And real-time RT-PCR showed that sap from J. mandshurica increased mRNA level of AQP3 and HAS2 gene and increased hyaluronic acid production in HaCaT cells. These results indicated that the sap from J. mandshurica can potentially be used for developing cosmetic ingredient for skin moisturizing and anti-aging.

• Research in Plant Disease
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• v.26 no.3
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• pp.190-193
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• 2020

In 2014, Anthracnose symptoms were observed on fruit of pumpkin in Gangneung, Gangwon in Korea. The typical symptoms on fruit surfaces were circular lesions, brown, shriveled with salmon-colored spore masses on the spots. A fungal isolate was obtained from symptomatic on fruit and cultured on potato dextrose agar at 25℃. The color of the upper surface of the colony varied from white to gray with occurrence of salmon-colored conidial masses and was red to violet on the underside. The causal fungus of anthracnose isolated from the diseased fruits was identified as Colletotrichum fioriniae based on mycological characteristics and sequences of the internal transcribed spacer, glyceraldehyde-3-phosphate dehydrogenase, chitin synthase-1 gene, histone H3, actin gene, beta-tubulin gene region. Pathogenicity tests of the isolate were performed on pumpkin fruit by both wound and non-wound inoculation with conidial suspension (1×10⁶ conidia/ml) and incubated at 25℃. Lesions were observed on both wounded and non-wounded fruit of pumpkin after 7 days inoculation in only C. fioriniae. The pathogen was re-isolated from the lesions of inoculated fruits. To our knowledge, this is the first report of anthracnose on fruit of pumpkin caused by C. fioriniae in Korea.