• Journal of Mycology and Infection
• /
• v.23 no.4
• /
• pp.111-114
• /
• 2018

A 19-year-old woman presented with an asymptomatic cutaneous discoloration on her nape. Dermatological examination revealed localized dark brown to dark pigmented velvety macules and patches. She denied a past medical history, except for a 7-kg weight gain over a 6-months period. Histopathologically, the specimen showed hyperkeratosis, epidermal hyperplasia, mild acanthosis, and papillomatosis. In addition, keratin material and fungal spore were noted between the papilloma ridges. Periodic acid-Schiff special stain showed a positive result for the fungal spore in the horny layer. She was treated with a daily oral dose of terbinafine and topical flutrimazole. After 12 weeks of treatment, she is currently under observation without pigmentation and adverse effect. We considered the initial diagnosis as acanthosis nigricans because of weight gain, similar clinical features, and histological findings. However, the final diagnosis was hyperkeratotic head and neck Malassezia dermatosis considering the presence of yeast and the dramatic improvement after antifungal treatment. To the best of our knowledge, hyperkeratotic head and neck Malassezia dermatosis is not well characterized in the literature. It is an unusual variant of pityriasis versicolor. The skin lesion appears brown to dark, scaly, and hyperkeratotic macules and patches located on the face and neck. Here, we reported an unusual case of hyperkeratotic head and neck Malassezia dermatosis.

• Microbiology and Biotechnology Letters
• /
• v.39 no.3
• /
• pp.287-293
• /
• 2011

The purpose of this study was to isolate and characterize fungal deteriogens, which induce discoloration of the cement tunnel, and calcite forming bacteria (CFBs), which have antifungal activity against fungal deteriogens. Isolation of mold, bacteria and yeast was performed using several solid media and partially identified using internal transcribed spacer (ITS); 5.8S rRNA gene sequencing and 16s rDNA sequencing. A total of 19 microbial strains were identified with the most widely distributed fungal strain being Cladospirum sphaerospermum. In addition, five bacteria derived from the tunnel were identified as CFBs. Amongst the latter, Bacillus aryabhatti KNUC205 exhibited antifungal activity against Cladospirum sphaerospermum KNUC253 and Aspergillus niger KCTC6906 as concentrated filtered supernatants.

• Journal of Korea Technical Association of The Pulp and Paper Industry
• /
• v.42 no.2
• /
• pp.20-26
• /
• 2010

Paper composed mainly of organic materials and they can be used as nutrient by microorganisms. Therefore microorganisms are damaging the important documents and works of art irreversibly. Previous research reported that mycelium or spores of the fungi were observed on the wax of the volumes of King Sejong especially were heavily deteriorated by fungi. Fungal strains isolated from the annals of Joseon dynasty were identified as Biscogniauxia atropunctata, Aspergillus versicolor, Penicillium polonicum, Ceriporia lacerata, Irpex lacteus. Especially Aspergillus and Penicillium are able to grow on the substrates having a 7-8% moisture content, which is much lower than the general storage condition (RH55-60%) of the paper cultural properties. Moreover, they are known as fungi cause paper deterioration and discoloration. In this study, we selected Aspergillus versicolor and Penicillium polonicum among five strains, then biological aging has been executed for 30 days. The growth of Aspergillus versicolor and Penicillium polonicum in wax was lower than wax treated paper and Hanji. The growth of them in beeswax treated paper and Hanji both were excellent.

• The Plant Pathology Journal
• /
• v.19 no.3
• /
• pp.184-187
• /
• 2003

Verticillium wilt was first observed in 2001 on potatoes (Solanum tuberosum) cv. Superior at Daegwallyong area, one of the major seed potato producing areas in Korea. The wilted potato plants showed typical symptoms including gradual yellowing and interveinal necrosis. There was discoloration in the vascular tissues of the infected stems which turned light brown. Fungal isolates from discolored vascular tissues were whitish to creamy with folding on potato dextrose agar medium, where they used to produce resting dark mycelia but no micro-sclerotia. Conidiophores were septate with side branches, swelled at the base, and arranged in a whorl. Conidia were 2.5-11.2$\times$2.0-4.5 $\mu\textrm{m}$ um in size and were borne in small clusters at the tips of phialides. Optimal temperature range for mycelial growth was $25-30^{\circ}C$. Based on these cultural and morphological characteristics, the fungus was identified as Verticillium albo-atrum Reink & Berth. Pathogenicity tests by root dipping method revealed that the fungus caused the same symptoms as observed in naturally infected potato plants. This is the first report of Verticillium wilt on potato caused by Verticillium albo-atrum in Korea.

• Journal of Microbiology and Biotechnology
• /
• v.14 no.1
• /
• pp.188-192
• /
• 2004

The main aim of this study was to investigate the sterilization effects of microwave-induced argon plasma at atmospheric pressure on paper materials contaminated with fungi. Plasma-treated filter papers showed no evidence to an unaided eye of burning or paper discoloration due to the plasma treatment. All fungi were perfectly sterilized in less than 1 sec, regardless of strains. These results indicate that this sterilization method for paper materials is easy to use, requires significantly less time than other traditional methods and different plasma sterilization methods, and is also nontoxic.

• 한국균학회소식:학술대회논문집
• /
• 2015.11a
• /
• pp.18-18
• /
• 2015

Wilt disease in Oak trees occurs during summer season in Korea. Mass attack of trees by an ambrosia beetle (Platypus koryoensis) was the characteristic feature before appearance of the wilting symptoms. Raffaelea sp. caused the discoloration of xylem area called as wound heartwood. Raffaelea sp. was observed both on the body surfaces and inside the mycangia of the beetle Platypus sp. The scanning electron microscope (SEM) analysis showed that fungal spores were present within the wall of gallery and vessels that formed tyloses. The results revealed that the water movement in vessels was blocked as the fungus started to grow which caused the formation of tyloses thereby resulting wilt symptoms. We found that both female and male beetle Platypus sp. had fungi on their bodies and their large and small mycangia. This study confirmed that the fungus was transferred to oak trees by Platypus sp.

• Mycobiology
• /
• v.44 no.4
• /
• pp.319-324
• /
• 2016

Dieback in strawberry (Seolhyang cultivar) was first observed during the nursery season (June to September) in the Nonsan area of Korea in the years 2012 and 2013. Initial disease symptoms included dieback on runners, as well as black rot on roots, followed by wilting and eventually blackened, necrotic discoloration in the crowns of daughter plants. A fungus isolated from the diseased roots, runners, and crowns is close to Lasiodiplodia theobromae based on morphological characteristics. Analysis of a combined dataset assembled from sequences of the internal transcribed spacer and translation elongation factor 1- alpha genes grouped nine fungal isolates with the type strain of L. theobromae. The isolates showed strong pathogenicity on strawberry cultivars Kumhyang, Seolhyang, and Akihimae, fulfilling Koch's postulates. Based on these results, the pathogen responsible for dieback on strawberry plants in Korea was identified as L. theobromae.

• Journal of the korean academy of Pediatric Dentistry
• /
• v.34 no.3
• /
• pp.468-472
• /
• 2007

The Wiskott-Aldrich Syndrome (WAS) is an inherited immunodeficiency caused by a variety of mutations in the gene encoding the WAS protein (WASp). First described in 1937 by Wiskott, the incidence of WAS has so far been estimated at 4 in 106 live births. The Wiskott-Aldrich Syndrome is an X-linked condition characterized by 1) an increased tendency to bleed caused by a reduced number of platelets, 2) recurrent bacterial, viral and fungal infections, and 3) eczema of the skin. The purpose of this report is to present cases highlighting the clinical features of the syndrome and the required considerations in the treatment of patients. The report consists of two particular cases: a 2-year-11-month-old boy seen for a routine oral examination prior to his bone marrow transplantation and a 2-year-6-month-old boy with herpes gingivostomatitis and teeth discoloration.

• Research in Plant Disease
• /
• v.10 no.4
• /
• pp.313-318
• /
• 2004

Internal fruit rot of cucumber was observed in several locations in Korea. Incidence of the disease reached up to 21.5% and averaged 4.2% in the fields surveyed. The disease started at blossom ends of cucumber fruits. Internal tissues of infected fruit tips showed brown discoloration over 2 cm in length and 2 mm in diameter. Subsequently, the brown discoloration was extended into the carpels, and the surface of the infected fruit tips was rugged. Fungal isolates from the internal tissues of diseased fruits were identified as Didymella bryoniae based on mycological characteristics. Temperature for mycelial growth of isolates ranged $5{\sim}32^{\circ}C$ with optimal temperature between $26{\sim}28^{\circ}C$. Similar symptoms were developed in the internal part of the cucumber fruit when conidial suspensions of the isolates were inoculated to the flower of cucumber. Furthermore, Didymella bryoniae isolates from other plant parts of cucumber, watermelon, oriental melon, melon and pumpkin also showed the similar symptoms in the internal part of cucumber fruits by inoculation tests. Temperature range for occurrence of internal fruit rot of cucumber was $10{\sim}32^{\circ}C$ with optimal temperature of $25{\sim}28^{\circ}C$.

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