• Mycobiology
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• v.32 no.4
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• pp.160-163
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• 2004

Medicinal plants play important roles in controlling plant diseases as one of the safest and ecofriendly methods. These plants have been used in the form of crude extracts as well as active principles in vitro and under field conditions to control plant diseases. Among the active principles, alkaloids have shown significant antifungal activity. We have investigated the effect of two alkaloids viz., (-)-corydahnine and (-)-isocorypahnine isolated from Corydalis chaerophylla, against spore germination of some plant pathogenic and saprophytic fungal spores. Significant inhibition of spore germination at 100 ${\mu}g/ml$ was seen against Curvularia penniseti, Curvularia sp. and Colletotrichum gloeosporioides by (-)-corydahnine but (-)-isocorypalmine was also effective against fungi included in the experiment.

• Korean Journal Plant Pathology
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• v.10 no.1
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• pp.13-17
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• 1994

A semiselective agar medium (XCO) was developed for the isolation of bacterial blight pathogen, Xanthomonas campestris pv. oryzae, from rice seed. The medium contained yeast extract 1.0 g, peptone 2.0 g, sucrose 5.0 g, sodium glutamate 1.0 g, FeSO4.7H2O 0.05 g, Fe.EDTA 1 mg, cephalexin 20 mg, Evan blue (0.1%) 1.5 ml, bromcresol purple (0.1%) 2.5ml, cycloheximide 100 mg and agar 15.0 g per liter. Colonies of X. c. pv. oryzae were 4~5 mm in diameter, smooth, round, blue (darker center) and convex after 6 days incubation at 28$^{\circ}C$. The recovery of 6 isolates of X. c. pv. oryzae on the XOC medium ranged from 81% to 120% (mean 98.2%) in comparison to Wakimoto's medium. The number of saprophytic bacteria from 10 rice seed lots on XCO medium was reduced to 70.4% of that on Wakimoto's medium. The recovery of X. c. pv. oryzae added to rice seed on XOC medium ranged from 67% to 87% (mean 75.6%) of that on Wakimoto's medium.

• Korean Journal of Medicinal Crop Science
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• v.26 no.2
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• pp.113-118
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• 2018

Background: Gastrodia elata Blume is a saprophytic perennial plant in the Orchidaceae family, because of its agricultural and medicinal effectiveness, researchers focus on its genome and chemical components. However, cytogenetic information based on the chromosome structure and composition to construct chromosomal backbone for genome sequencing research and for the development and breeding of plants is very limited. Methods and Results: We determined the metaphase chromosome composition of the G. elata genome by fluorescence in situ hybridization (FISH) using 5S and 45S rDNAs and telomeric repeat probes. The nuclear genome of G. elata was organized into 2 n = 36, with relatively small ($2.71-5.50{\mu}m$)chromosomes that showed gradual decrease in size. Conglutination phenomenon was observed among the metaphase chromosomes, and it was distinguished from that in other plant metaphase chromosome spreads. One pair of signal was detected for each 5S and 45S rDNA in the pericentromeric region and interstitial region on the short arm of chromosomes 10 and 4, respectively, and telomeric DNA signals were detected in the terminal region of most chromosomes. Conclusions: To our knowledge, this is the first FISH chromosome composition result in G. elata and could be useful in more comprehensive molecular cytogenetic and genomic analyses as well as breeding programs of the medicinal plant G. elata.

• Journal of Microbiology and Biotechnology
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• v.25 no.5
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• pp.579-588
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• 2015

Fungi of the genus Pestalotiopsis have drawn attention for their capability to produce an array of bioactive secondary metabolites that have potential for drug development. Here, we report the determination of a polyketide derivative compound, pestalotiollide B, in the culture of the saprophytic fungus Pestalotiopsis microspora NK17. Structural information acquired by analyses with a set of spectroscopic and chromatographic techniques suggests that pestalotiollide B has the same skeleton as the penicillide derivatives, dibenzodioxocinones, which are inhibitors of cholesterol ester transfer protein (CETP), and as purpactins A and C', inhibitors of acyl-CoA:cholesterol acyltransferase (ACAT). Strain NK17 can make a fairly high yield of pestalotiollide B (i.e., up to 7.22 mg/l) in a constitutive manner in liquid culture. Moreover, we found that a putative histone deacetylase gene, designated as hid1, played a role in the biosynthesis of pestalotiollide B. In the hid1 null mutant, the yield of pestalotiollide B increased approximately 2-fold to 15.90 mg/l. In contrast, deletion of gene hid1 led to a dramatic decrease of conidia production of the fungus. These results suggest that hid1 is a modulator, concerting secondary metabolism and development such as conidiation in P. microspora. Our work may help with the investigation into the biosynthesis of pestalotiollide B and the development for new CETP and ACAT inhibitors.

• The Plant Pathology Journal
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• v.16 no.4
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• pp.236-241
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• 2000

A selective agar medium was developed and tested for the isolation of Acidovorax avenae subsp. avenae, the causal bacterial pathogen of bacterial brown stripe, from rice seeds. The new selective agar medium, designated sorbitol pyroglutamic acid agar (SPA) medium, contained 0.5 g of $K_2$HPO$_4$, 3.0 g of Na$_2$HPO$_4$, 2.0 g of D-sorbitol, 0.2 g of L-pyroglutamic acid, 10.0 $m\ell$ of tween 80, 40.0 mg of victoria blue B, 15.0 g of agar, 150.0 mg of ampicillin and 25.0 mg of vancomycin per litter. Colonies of A. avenae subsp. avenae on SPA medium were smooth, round, convex, shiny, blue and 1.5-2.0 mm in diameter 4 days after incubation at 28$^{\circ}C$. Blue colored colony having dark blue zone was typical type of A. avenae subsp. avenae colonies on the medium. Mean recovery of 8 isolates of A. avenae subsp. avenae on the selective SPA medium was 95.8% in comparison to that on KB medium. The saprophytic bacteria were reduced to 97.9% on SPA medium compared to those on KB medium. Most of other rice seedborne bacteria as well as reported pathogenic bacteria were failed to grow on SPA medium. This medium was highly selective for recovering A. avenae subsp. avenae from rice seed samples, and it could be used to enhance the recovery of this bacterium from rice seed samples, which may be contaminated with large numbers of competing microorganisms.

• The Plant Pathology Journal
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• v.24 no.2
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• pp.101-111
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• 2008

The fungal genus Alternaria is comprised of many saprophytic and endophytic species, but is most well known as containing many notoriously destructive plant pathogens. There are over 4,000 Alternaria/host associations recorded in the USDA Fungal Host Index ranking the genus 10th among nearly 2,000 fungal genera based on the total number of host records. While few Alternaria species appear to have a sexual stage to their life cycles, the majority lack sexuality altogether. Many pathogenic species of Alternaria are prolific toxin producers, which facilitates their necrotrophic lifestyle. Necrotrophs must kill host cells prior to colonization, and thus these toxins are secreted to facilitate host cell death often by triggering genetically programmed apoptotic pathways or by directly causing cell damage resulting in necrosis. While many species of Alternaria produce toxins with rather broad host ranges, a closely-related group of agronomically important Alternaria species produce selective toxins with a very narrow range often to the cultivar level. Genes that code for and direct the biosynthesis of these host-specific toxins for the Alternaria alternata sensu lato lineages are often contained on small, mostly conditionally dispensable, chromosomes. Besides the role of toxins in Alternaria pathogenesis, relatively few genes and/or gene products have been identified that contribute to or are required for pathogenicity. Recently, the completion of the A. brassicicola genome sequencing project has facilitated the examination of a substantial subset of genes for their role in pathogenicity. In this review, we will highlight the role of toxins in Alternaria pathogenesis and the use of A. brassicicola as a model representative for basic virulence studies for the genus as a whole. The current status of these research efforts will be discussed.

• Journal of Microbiology and Biotechnology
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• v.25 no.7
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• pp.1007-1014
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• 2015

Plectasin, the first defensin extracted from a fungus (the saprophytic ascomycete Pseudoplectania nigrella), is attractive as a prospective antimicrobial agent. The purpose of this study was to establish a bacterium-based production system and evaluate the antimicrobial activity of the resulting plectasin. A gene encoding plectasin, with the codon preference of Escherichia coli, was optimized based on its amino acid sequence, synthesized using genesplicing with overlap extension PCR, and inserted into the expression vector pGEX-4T-1. The fusion protein was expressed in the soluble fraction of E. coli and purified using glutathione Stransferase affinity chromatography. Plectasin was cleaved from the fusion protein with thrombin and purified by ultrafiltration. The purified plectasin showed strong, concentrationdependent antimicrobial activity against gram-positive bacteria, including antibiotic-resistant bacteria, especially penicillin-resistant Enterococcus faecium. This antimicrobial activity was equal to chemically synthesized plectasin and was maintained over a wide range of pH and temperatures. This soluble recombinant expression system in E. coli is effective for producing plectasin at a relatively lower cost, and higher purity and efficiency than prior systems, and might provide a foundation for developing a large-scale production system. Overall, plectasin shows potential as a novel, high-performance, and safe antibiotic for the treatment of refractory diseases caused by drug-resistant bacterial strains.

• Tuberculosis and Respiratory Diseases
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• v.49 no.1
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• pp.105-110
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• 2000

Pulmonary aspergillosis is classified as a saprophytic, allergic, and invasive disease. Chronic necrotizing pulmonary aspergillosis is categorized as an invasive pulmonary aspergillosis. Most invasive pulmonary aspergillosis have acute and toxic clinical features but chronic necrotizing pulmonary aspergillosis is characterized by a subacute infection, most commonly seen in patients with altered local defense system from preexisting pulmonary disease or in mild immunocompromised patients. Pulmonary artery aneurysm due to this infection is termed as a mycotic aneurysm, etiology of which are tuberculosis, syphilis, bacteria and fungus. We report a case of chronic necrotizing pulmonary aspergillosis complicating pulmonary aneurysm in a 62 year-old man who was presented with cough, sputum, and fever. Chest radiographs showed a rapid, progressive cavitary lesion and pulmonary artery aneurysm. Angioinvasion of asper gillus was revealed by pathology after operative removal of left upper lobe containing the pulmonary artery aneurysm. He was treated with itraconazole.

• The Korean Journal of Mycology
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• v.35 no.1
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• pp.11-27
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• 2007

This study was conducted to investigate the diversity of higher fungi in NaeJangSan National Park from April 2004 to November 2006. The obtained results from investigation were as follows. The total of 5 classes, 19 orders, 60 families, 168 genera and 418 species (including 10 families, 13 genera and 15 species unrecorded) including saprophytic and ectomycorrhizal fungi was investigated. The higher fungi were classified into 47 families, 143 genera and 384 species in Basidiomycotina, 9 families, 19 genera and 28 species in Ascomycotina and 4 families, 6 genera and 6 species in Myxomycota. It was turned out that most of the higher fungi belong to Hymenomycetidae in Basidiomycotina, for which 34 families 122 genera, and 353 species were observed. Dorminant species belonged to Tricholomataceae(64 species) Russulaceae(39 species), Polyporaceae(36 species) and Boletaceae(36 species). The mushroom occurrence of higher fungi was closely related to climatic conditions such as high air temperature and lots of rainfall from July to September. The environment which has a favorable influence of mushroom occurrence was air temperature, relative humidity and rainfall of climatic environment.

• Journal of Chest Surgery
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• v.29 no.5
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• pp.530-535
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• 1996

Saprophytic aspergillosis (aspergilloma), a potentially life-threatening disease from the colonization of lung cavities by the ubiquitous fungus Aspergillus fumigatus, has been of surgical concern. Twelve patients with symptomatic aspergilloma underwent operative procedures at Pusan national University Hospital between January 1, 1984 and August 31, 1994. The mean age of the patients was 38.8 years and nine of them had hemoptysis; in two it was massive and life-threatening. Wine of the patients had underlying causes of cavitary lung disease and tuberculosis was the most common cause. Lobectomy was the most commonly performed procedure (in six) . Several major complications including excessive bleeding (2), and pneumonia (2), and empyema with bronchopleural fistula (1) occurred .and one patient died (operative mortality=8.3%). There were no recurrent symptoms in any of the 11 operative survivors during the follow-up period. It is concluded that early, aggressive surgical intervention can provide definite cure in established aspergilloma, even with minimal symptoms.