• Microbiology and Biotechnology Letters
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• v.23 no.5
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• pp.565-572
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• 1995

The aim of the present research program was to develop a strain of actinomycetes producing extracellular cathepsin B inhibitor. Soil samples were collected from various sites in Korea and a number of actinomycetes were isolated from the soil samples by applying various physical and chemical pretreatments. An economical and effective method was developed for the screening of strains producing low molecular weight cathepsin B inhibitor, and consequently a strain (SMF28) among over 700 isolates was selected. Chemotaxonomic and numerical identification were carried out for the isolate. Fifty taxonomic unit characters were tested and the data were analyzed numerically using TAXON program. The isolate was identified as a strain of Streptomyces chromofuscus.

• Microbiology and Biotechnology Letters
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• v.27 no.2
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• pp.113-117
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• 1999

As a basic study for quality improvement of Korean soybean paste and soybean sauce, we investigated on microflora of soybean paste and soybean sauce fermentation. Major Microorganisms were isolated from the sample pastes and sauces, and identified systematically. Selected Microorganisms were identified by MIS whole cell fatty acid analysis by gas chromatography. Identification results showed that Bacillus licheniformis, bacillus pumilis and Bacillus subtilis were dominant in soybean paste and Staphylococcus vitulus, Bacillus subtilis, Bacillus pumilus, and Lactobacillus fermentum were dominant in soybean sauce. It seemed that these Microorganisms played an important role in soybean paste and soybean sauce fermentation and could be used for the further studies such as protease and amylase activities.

• Journal of Microbiology
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• v.35 no.1
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• pp.10-14
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• 1997

The database of metabolic fingerprints generated using the GIolog system of lactic acid bacteria isolated from kimchi, described by Lee et al. (8), was used for the identification of 75 Leuconostoc isolates. The test strains were isoalted using a selective isolation medium specific for the genus Leuconostoc and examined for their ability to oxidize carbon sources using the Biolog system. The results show that the 75 test strains were identified to the known Leuconostoce clusters. It is suggested that the Biolog system can be applied for rapid identification of lactic acid bacteria isolated from kimchi.

• The Journal of the Korean Society for Microbiology
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• v.34 no.6
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• pp.561-571
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• 1999

Diagnosis of mycobacterial infection is dependent upon the isolation and identification of causative agents. The procedures involved are time consuming and technically demanding. To improve the laborious identification process mycobacterial systematics supported by gene analysis is feasible, being particularly useful for slowly growing or uncultivable mycobacteria. To complement genetic analysis for the differentiation and identification of mycobacterial species, an alternative marker gene, rpoB encoding the ${\beta}$ subunit of RNA polymerase, was investigated. rpoB DNAs (342 bp) were amplified from 52 reference strains of mycobacteria including Mycobacterium tuberculosis H37Rv (ATCC 27294) and clinical isolates by the PCR. The nucleotide sequences were directly determined (306 bp) and aligned using the multiple alignment algorithm in the MegAlign package (DNASTAR) and MEGA program. A phylogenetic tree was constructed with a neighborhood joining method. Comparative sequence analysis of rpoB DNA provided the basis for species differentiation. By being grouped into species-specific clusters with low sequence divergence among strains belonging to same species, all the clinical isolates could be easily identified. Furthermore RFLP analysis enabled rapid identification of clinical isolates.

• The Journal of the Korean Society for Microbiology
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• v.20 no.1
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• pp.35-44
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• 1985

Isolation and identification of anaerobic bacteria from blood cultures are still technically demanding procedures. Recently, with the use of gas liquid chromatography, the accuracy of identification is much improved. However, there has never been a satisfactory data analysis on anaerobic bacteremia in Korea. The authors evaluated both the clinical and the bacteriological data of 129 anaerobic bacteremias found at the Yonsei Medical Center during the period of 1973 to 1984. The most frequently isolated anaerobic bacteria were Bacteroides (52.7%), among which the major species was B. fragilis (38.7%). Incidence of anaerobic bacteremia by sex was 57% in male and 43% in female. Mortality was higg in groups below 1-year old and above 50-year old. The cause of death seemed closely correlated with the patient's age, general condition and the severity of the underlying disease. Various neoplasms were the most common (20%) underlying diseases predisposing the anaerobic bacteremia. Biliary tract was considered the most frequent route of infection in anaerobic bacteremia. The frequent clinical signs in anaerobic bacteremia were fever (65%), followed by liver function abnormality (29%), jaundice (20%) and hypotention(18%). When analysis of positive rate of blood culture was made on the patients from whom 4 cultures were done within 24 hours, it was found that 33% of the samples were positive. Isolation rate of anaerobic bacteria in thioglycollate medium was 83.8%, while it was 44% in Tryptic soy broth. Among the anaerobic bacteremia, 25.4% were polymicrobial infections with aerobic bacteria (92.5%), such as E. coli(33.3%). From these studies, it is concluded that B. fragilis is the most important causative organism in anaerobic bacteremia, with high fatality, particularly in those who have underlying diseases. The ports of entry are mainly biliary, gastrointestinal and female genital tract. Fever is the most frequent clinical sign. Single blood culture is not sufficient to detect all anaerobic bacteremia, therefore more cultures with optimal time interval are needed. The incidence of polymicrobial infection in anaerobic bacteremia is higher than that in overall bacteremia.

• The Korean Journal of Mycology
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• v.44 no.2
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• pp.108-112
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• 2016

This study focused on the isolation of wild yeasts from the soils of an herb park in Seoul, Korea, and characterization of unrecorded yeasts. Fifteen yeast strains of nine species were isolated and identified. Among them, strains of the Cryptococcus genus, such as Cryptococcus laurentii (2 strains), Cryptococcus saitoi (two strains), Cryptococcus podzolicus (2 strains), and Cryptococcus sp. (2 strains) were dominant. Candida boleticola SU14-2, Candida novakii SU6-2 and Cryptococcus podzolicus SU18-3 were also screened as newly recorded yeasts in Korea. Candida novakii SU6-2 formed ascospores and a pseudomycelium, and Candida boleticola SU14-2 grew well in the 5% NaCl-containing yeast extract-peptone-dextrose medium.

• Natural Product Sciences
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• v.26 no.3
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• pp.214-220
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• 2020

Brassica oleracea var. gongylodes (red kohlrabi) is a biennial herbaceous vegetable whose edible bulbotuber-like stem and leaves are consumed globally. Sliced red kohlrabi tubers were extracted using methanol and the concentrated extract was partitioned successively with dichloromethane (CH₂Cl₂), ethyl acetate (EtOAc), n-butanol (n-BuOH) and water (H₂O). Repeated column chromatography of EtOAc fraction through silica, sephadex LH-20 and RP-18 gel led to isolation of eleven compounds of which compound 1 was a new glycosylated indole alkaloid derivative, 1-methoxyindole 3-carboxylic acid 6-O-β-D-glucopyranoside. Others were known compounds namely, β-sitosterol glucoside (4), 5-hydroxymethyl-2-furaldehyde (5), methyl-1-thio-β-D-glucopyranosyl disulfide (6), 5-hydroxy-2-pyridinemethanol (7), (3S,4R)-2-deoxyribonolactone (8), n-butyl-β-D-fructopyranoside (9), uridine (10) and three fructose derivatives, D-tagatose (11), β-D-fructofuranose (12) and β-D-fructopyranose (13). Similarly, isolation from CH₂Cl₂ fraction gave two known indole alkaloids, indole 3-acetonitrile (2) and N-methoxyindole 3-acetonitrile (3). The structure elucidation and identification of these compounds were conducted with the help of ¹³C and ¹H NMR, HMBC, HMQC, EIMS, HR-ESIMS and IR spectroscopic data, and TLC plate spots visualization. Compounds 2, 3, 4, 5, 6, 7, 8 and 9 are noted to occur in kohlrabi for the first time. Different bioactivities of these isolated compounds have been reported in literature.

• Korean Journal of Veterinary Research
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• v.27 no.1
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• pp.61-68
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• 1987

This study was conducted to determine the microorganisms inhabitating in cow genitalia and their antimicrobial drug susceptibility. During the period between July, 1985 and February, 1986, a total of 111 cow genitalia, 58 from Korean native and 53 from dairy cow, were sampled at three abattoirs. Gross pathological examination and bacterial isolation and identification were performed from the genital samples. In addition antimicrobial drug susceptibility test for the microorganisms isolated, some synergistic activity among drugs were examined on the major organism isolated from the cases of endometritis and pyometra. The results are summerized as follows: 1. Among the bacteria isolated from the genitalia, Staphylococcus spp., C. pyogenes, E. coli, Proteus spp., Streptococcus spp., Bacillus spp. were most frequently isolated whereas the genera of Pasteurella, Pseudomonas, Klebsiella and Yersina were detected far less frequently. 2. In Korean native cow the genera of Straphylococcus and Steptococcus were more isolated than dairy cow while in dairy cow the genera of Corynebacterium, Proteus, Escherichia were more of ten isolated than Korean native cow. 3. From cow genital organs showing lesions of endometritis and prometra, C. pyogenes was most frequently isolated, the isolation rate being 60 percent, and follow by Staphylococcus spp., Proteus spp., E. coli and Pasteurella spp. in the order. 4. Antimicrobial drug susceptibility test conducted on the major organisms isolated showed that all the isolates were susceptible to gentamicin, cephalosporin and sulfisoxazole, but resistant to tetracycline and penicillin. 5. Twenty-nine isolates of C. pyogenes were submitted to the synergistic activity test of cephalosporin, kanamycin and streptomycin with penicillin. Synergists were demonstrated in 90 percent, 31 percent and 27 percent of isolates examined by the combined use of penicillin and cephalosporin, penicillin and kanamycin, penicillin and streptomycin, respectively. About 10 percent of the isolates were found to be indifferent by the synergism test.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.39 no.2
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• pp.144-152
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• 2011

This paper presents a new scheme for fault detection and isolation in the satellite system. The purpose of this paper is to develop a fault detection, isolation and diagnosis algorithm based on the bank of interacting multiple model (IMM) filter for both total and partial faults in a satellite attitude control system (ACS). In this paper, IMM are utilized for detection and diagnosis of anticipated actuator faults in a satellite ACS. Other fault detection, isolation (FDI) schemes using conventional IMM are compared with the proposed FDI scheme. The FDI procedure is developed in two stages. In the first stage, 11 EKFs actuator fault models are designed to detect wherever actuator faults occur. In the second stage of the FDI scheme, two filters are designed to identify the fault type which is either the total or partial fault. An important feature of the proposed FDI scheme can decrease fault isolation time and figure out not only fault detection and isolation but also fault type identification.

• The Korean Journal of Pesticide Science
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• v.12 no.1
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• pp.97-101
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• 2008

For the isolation of Actinomycetes showing nematocidal activity against Pine wood nematode, Bursaphelenchus xylophilus, about 2000 culture broth of Actinomycetes were tested and their activity were compared with that of Streptomyces avermitilis resulting a selected strain AW050027. The cultural, morphological and physiological analysis was performed for the identification of a selected strain. Phylogenetic analyses based on 165 rDNA gene sequences showed that the selected strain AW050027 belonged to the genus Micromonospora and M. corioriae $NAR01^T$ was the closest neighbors, sharing 98.9% 165 rDNA gene sequence similarity.