• Toxicological Research
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• v.26 no.1
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• pp.47-52
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• 2010

The Malassezia fungi are responsible for various human skin disorders including dandruff and seborrheic dermatitis. Of the Malassezia fungi, Malassezia globosa (M. globosa) is one of the most common in human scalp. The completed genome sequence of M. globosa contains four putative cytochrome P450 genes. To determine the roles of Malassezia P450 enzymes in the biosynthesis of ergosterol, we isolated MGL3996 gene from M. globosa chromosomal DNA by PCR. The MGL3996 gene encodes an enzyme of 616 amino acids, which shows strong similarity with known CYP52s of other species. MGL3996 gene was cloned and expressed in Pichia pastoris (P. pastoris) heterologous yeast expression system. Using the yeast microsomes expressing MGL3996 protein, a typical P450 CO-difference spectrum was shown with absorption maximum at 448 nm. SDS-PAGE analysis revealed a protein band of apparent molecular weight 69 kDa and Western blot with anti-histidine tag antibody showed that MGL3996 was successfully expressed in P. pastoris. Cloning and expression of a new P450 gene is an important step to study the P450 monooxygenase system of M. globosa and to understand the role of P450 enzymes in pathophysiology of dandruff.

• Mycobiology
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• v.41 no.2
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• pp.67-72
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• 2013

Pathogenic microbes secrete various enzymes with lipolytic activities to facilitate their survival within the host. Lipolytic enzymes include extracellular lipases and phospholipases, and several lines of evidence have suggested that these enzymes contribute to the virulence of pathogenic fungi. Candida albicans and Cryptococcus neoformans are the most commonly isolated human fungal pathogens, and several biochemical and molecular approaches have identified their extracellular lipolytic enzymes. The role of lipases and phospholipases in the virulence of C. albicans has been extensively studied, and these enzymes have been shown to contribute to C. albicans morphological transition, colonization, cytotoxicity, and penetration to the host. While not much is known about the lipases in C. neoformans, the roles of phospholipases in the dissemination of fungal cells in the host and in signaling pathways have been described. Lipolytic enzymes may also influence the survival of the lipophilic cutaneous pathogenic yeast Malassezia species within the host, and an unusually high number of lipase-coding genes may complement the lipid dependency of this fungus. This review briefly describes the current understanding of the lipolytic enzymes in major human fungal pathogens, namely C. albicans, C. neoformans, and Malassezia spp.

• Journal of Veterinary Clinics
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• v.21 no.1
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• pp.35-44
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• 2004

This study was performed to examine the mycological features of canine skin. A total of 50 dogs with skin lesions were examined for dermatology from October, 2000 to April, 2001. The isolation rates of dermatophytes, yeast, filamentous fungi and superficial fungi were 36.4%, 13.5%, 35.3% and 13.6%. The dermatophytes isolated in dogs were Microsporum canins and Trichophyton mentagrophytes were 75% and 25%. The yeast and superficial fungi isolated in dogs were Candida albicans, Rhodntorula minnata, Candida ceferrii and Malassezia spp. were 16.7%. 16.7%, 16.7% and 50%. The filamentous fungi by Aspergillus funigatus, Aspergillus niger, Penicillum spp., Alternaria spp. were 12.5%, 12.5%, 50%, and 25%. In determine if polymerase chain reaction (PCR) could be applied for diagnosis of dermatophytes, yeast and filamentous fungi, control and clinical samples were tested. The size of specific PCR product in agarose gel was 340 bp for dermatophytes and 210 bp for yeast and filamentous fungi, respectively.

• Fisheries and Aquatic Sciences
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• v.12 no.1
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• pp.29-34
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• 2009

Fifty seven species of common seaweed from the coast of Korea were screened for antifungal activity against Malassezia species. Seaweeds as a source of bioactive compounds are able to produce a great variety of secondary metabolites with different activities. There are numerous reports on the biological activities of seaweeds against human pathogens, fungi, and yeasts, but only few contain data regarding inhibitory effects against Malassezia sp., a major cause of dandruff and seborrheic dermatitis. To help address this paucity of information, this work was carried out to examine the antifungal effects of seaweed extracts against M. furfur and M. restricta. Of the fifty seven species of marine algae screened for their potential antifungal activity, only 17 species (29.8%) exhibited inhibitory activity. In agar disc diffusion method, the ether extracts of Corallina pilulifera, Enteromorpha linza, Laminaria japonica, Symphyocladia latiuscula and Ulva sp. showed strong antifungal activity. To identify major constituents in seaweed extracts, four selected extracts were analyzed on' a GC-MS equipped with a flame ionization detector, and compared to spectral data from databases WILEY229.LIB and NIST107.LIB. Most constituents in seaweed extracts are fatty acid-related compounds. When we evaluated any acute toxicity, the ether extracts of the selected four species were not toxic in mice. According to these results, it can be suggested that these seaweed extracts are valuable for the development of therapeutic agents in treating dandruff and seborrheic dermatitis. Further investigations to determine its bioactive compound(s) are currently in progress.

• Journal of Veterinary Clinics
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• v.37 no.1
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• pp.1-8
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• 2020

Canine otitis externa is a common disorder in small animal practice with prevalence up to 20%. In a large percentage of cases, canine otitis externa is a chronic and recurrent disease also associated with drug-resistant bacteria that is difficult to treat with traditional antibiotics. Photodynamic therapy (PDT) is a new strategy to exterminate pathogenic microorganisms such as bacteria and fungi. The purpose of this study was to investigate the effectiveness of photodynamic therapy against canine otitis externa using three photosensitizer (PS); 5-Aminolevulinic acid (5-ALA) and Methyl aminolevulinic acid (MAL) with semiconductor laser diode (SLD, 635nm of wave length), Chlorophyll-lipoid complex (CLC) with light-emitting diode (LED, 660nm of wave length). After PDT, dogs showed improved Otitis Index Score (OTIS) in swelling, exudate, odor, and pain. A result of the cytology test revealed decrease of bacteria and malassezia count in the oil immersion field and colony forming units count. PDT was effective as a bacteriocide of methicillin-resistant Staphylococcus pseudintermedius (MRSP) and a fungicide of Malassezia pachydermatis. MAL and 5-ALA were more effective PS against canine otitis externa than CLC. These results suggest that PDT is a new strategy to exterminate pathogenic microorganisms such as bacteria and fungi. PDT can be considered as a new therapeutic approach for canine recurrent otitis externa and a countermeasure to drug resistance that is a disadvantage of traditional antibiotic and antifungal therapy.

• Korean Journal of Veterinary Research
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• v.39 no.3
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• pp.566-574
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• 1999

This study was conducted to examine the outbreak rate and the causative agents of otitis externa in 26 dogs (49 ears ; 23 dogs = bilateral, 3 dogs = unilateral), and the normal microfloras of external ear canal in 68 dogs(133 ears ; 65 dogs = bilateral, 3 dogs = unilateral ) in Taegu, 1997. The breed, living environment, sex, age and season distribution of otitic dogs were as follows : Dogs with erect and hairy ears(42.3%), pendulous and hairy ears(38.5%), indoor(92.3%), female(65.4%) and below one year old(38.5%) were more prevalent. According to season, otitis externa was mainly occurred between July and October. The major causative agents of canine otitis externa were Malassezia pachydermatis (32.7%), Staphylococcus aureus (26.5%) and S intermedius (16.3%). In the microorganism isolated 39 otitic ear canals, single infection was 53.8% and mixed infection was 46.2%. The normal microfloras of canine external ear canal were fungi including M pachydermatis, Aspergillus spp, Microsporum canis, Alternaria spp, Verticillium spp and Yeast, and bacteria including Staphylococcus spp(10 species including S xylosus), Bacillus spp, Corynebacterium spp, Listeria spp, Actinomyces pyogenes and Escherichia coli. No growth was 34.6%.

• Korean Journal of Veterinary Research
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• v.40 no.1
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• pp.94-100
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• 2000

This study was carried out to determine the causative agent and the epidemiological features of canine dermatitis in Tae-gu, Korea from 1997 to 1998. Specimens of collected from skin lesions were examined mycologically, parasitologically and bacteriologically. In all, 70 dogs of differing ages, gender and living environment were sampled. In mycological examination during this period, pathogenic fungi were cultured from 29(41.3%) of 70 canine specimens. Dermatophytes were cultured from 15(21.4%) and Malassezia pachydermatis were 14(20.0%) of the specimens. The frequent dermatophytes isolated were Microsporum canis (12.9%). Trichophyton mentagrophytes (4.3%), T rubrum (2.9%), T raubitschekii and M gypseum (each 1.4%). There was a high proportion of positive cultures from dogs less than 1 year and over than 3 years of age, and in some long haired breeds, but there was no significant difference between the sexes, and the living environments. Although dermatophytes were more frequently isolated in spring and winter, no significant difference was detected in the seasonal distribution of the canine dermatophytosis. Out of 70 dogs, dermatitis ectoparasites(27.1%; Demodex canis 18.6% and Sarcoptes scabie 8.6%) and bacterial pyoderma(40.4%) were diagnosed. Demodex canis and Sarcoptes scabie were common canine ectoparasites, with a higher incidence in short haired breeds and in summer and winter. Bacterial pyoderma was a higher incidence in long haired breeds, and in summer. In the pathogenic agents isolated from 57 dogs(81.4%), single infection rate was 66.7%(38 dogs) and mixed infection rate was, 35.1%(19 dogs). In the majority of mixed infection cases, Gram positive cocci and Malassezia pachydermatis (in 5 cases, 8.8%), as well as ectoparasites(in 6 cases, 10.5%) were demonstrated simultaneously.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.60 no.3
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• pp.366-373
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• 2015

This study was conducted to clarify the antimicrobial effect, antioxidant and tyrosinase inhibitory activities of the biological composition having the Phytolacca americana, and to enhance the natural materials utilization of foods and cosmetics. The antimicrobial activities of the different parts of P. americana were evaluated using the agar diffusion test. The antimicrobial activity of P. americana was relatively high in Malassezia furfur known as a skin fungi and Vibrio parahaemolyticus compared to Escherichia coli and Staphy-lococcus epidermidis. However, the antimicrobial activity in Vibrio parahaemolyticus did not show at all parts of P. americana. Both the DPPH radical scavenging activity and ABTS radical scavenging activity have been increased with the higher concentration of methanol extract. In particular, leaf extract of P. americana exhibited the highest activity both ABTS radical scavenging activity and DPPH radical scavenging activity. The nitrite scavenging activity was decreased when the pH was changed from pH 1.2 to pH 6.0. The highest nitrite scavenging activity was exhibited from the methanol extract of fruit, followed by root, stem, and leaf at pH 1.2. However, the nitrite scavenging activity at pH of 6.0 was not almost detected. All plant parts of P. americana showed tyrosinase inhibitory activity. The highest activity was found in the stem, and followed by root, leaf, and fruit in order. These tyrosinase inhibitory activity was progressively increased in a concentration-dependent manner. In this experiment on the methanol extracts of different organ from P. americana, we confirmed that the extract of P. americana showed potent tyrosinase inhibitory activity. Taken together, we conjectured that the P. americana had the potent biological activities, therefore this plant having various functional components could be a good material for development into source of natural food additives and cosmetics.

• Journal of Veterinary Clinics
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• v.33 no.6
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• pp.392-394
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• 2016

A 2-year-old spayed female Persian cat presented to Kangwon National University Veterinary Medical Teaching Hospital with pruritus and erythema on the tips of both ears, around the eyes, and in the caudal abdomen. This patient had previously been prescribed prednisolone, but did not respond positively to the treatment. A skin screening test revealed that there were no fleas or fungi, and that only cocci were present. Blood testing revealed no remarkable findings. The patient was prescribed antibiotics (amoxicillin-clavulanic acid 25 mg/kg for 2 weeks) with no prednisolone. After 2 weeks, clinical signs were alleviated and the skin screening test showed no signs of cocci. However, clinical signs recurred even with the prescription of antibiotics. Four weeks after the steroid-free interval, Malassezia spp. hypersensitivity was detected upon a serum allergy test, and pathological analysis confirmed eosinophilic and mastocytic superficial dermatitis in the caudal abdomen. Based on these results, we suspected allergic dermatitis and prescribed 7 mg/kg cyclosporine A once a day. After 3 weeks, clinical signs were resolved. Seven weeks after the first trial with cyclosporine A, we reduced the cyclosporine A dose to 7 mg/kg every other day. The patient's symptoms have since been well controlled for 6 months. This study suggests that cyclosporine A can be a good choice for treating cats with suspected allergic dermatitis that has not responded positively to steroid treatment.

• Journal of Life Science
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• v.18 no.2
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• pp.228-233
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• 2008

Antimicrobial activities of ethanol extracts of about 60 endemic Korean herbs and medicinal plants were investigated. When compared to the group treated with phenoxyethanol as a positive control, the growth of Pseudomonas aeruginosa was inhibited by Styrax japonica, Stevia rebaudiana, Morus Leaf, Coptis chinensis and Slavia miltorrhiza Bunge, the latter showing the strongest inhibition (97%). The growth of Staphylococcus aureus was inhibited by Acorus calamus, Pinus densiflora, Ginkgo biloba, Dryopteris crassirhizoma, Chrysanthemum zawadskii, Slavia miltorrhiza Bunge and Coptis chinensis, the latter showing the strongest inhibition (99%). The growth of yeast type fungi Candida albicans was inhibited to about 35% by Scutellaria baicalensis Geogr and about 33% by Coptis chinensis as determined by paper disk method. The growth of bacterium Malassezia furfur was inhibited by Paeonia lactiflora, Rosa multiflora, Coptis chinensis, Citrus aurantium L. subsp, Paeonia suffruticosa Andrews, and Galla rhois, the latter showing the strongest inhibition (57%). The growth of Propionibacterium acnes was inhibited by Galla rhois, Paeonia lactiflora, Morus bombycis, Cucumis sativus, Stevia rebaudiana, Coptis chinensis and Slavia miltorrhiza Bunge. Interestingly, Coptis chinensis and Slavia miltorrhiza Bunge showed the strongest inhibition (99%) similar to that in postive control. The possible components and their action modes were suggested and discussed.