• Journal of Life Science
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• v.26 no.1
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• pp.68-74
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• 2016

Perchlorate (ClO₄⁻) is an emerging pollutant detected in surface water, soil, and groundwater. Previous studies provided experimental evidence of autotrophic ClO₄⁻ removal with elemental sulfur (S⁰) particles and activated sludge, which are inexpensive and easily available, respectively. In addition, ClO₄⁻ removal efficiency was shown to increase when an enrichment culture was used as an inoculum instead of activated sludge. PCR-DGGE was employed in the present study to investigate the microbial community in the enrichment culture that removed ClO₄⁻ autotrophically. Microorganisms in the enrichment culture showed 99.71% or more ClO₄⁻ removal efficiency after a 7-day incubation when the initial concentration was approximately 120 mg ClO₄⁻/l. Genomic DNA was isolated from the enriched culture and its inoculum (activated sludge), and used for PCR-DGGE analysis of 16S rRNA genes. Microbial compositions of the enrichment culture and the activated sludge were different, as determined by their different DGGE profiles. The difference in DGGE banding patterns suggests that environmental conditions of the enrichment culture caused a change in the microbial community composition of the inoculated activated sludge. Dominant DGGE bands in the enrichment culture sample were affiliated with the classes β-Proteobacteria, Bacteroidetes, and Spirochaetes. Further investigation is warranted to reveal the metabolic roles of the dominant populations in the ClO₄⁻ degradation process, along with their isolation.

• Journal of Dairy Science and Biotechnology
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• v.32 no.2
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• pp.131-139
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• 2014

The aim of this study was to manufacture Cutting-Gouda cheese and to investigate the change in physicochemical properties of Cutting-Gouda cheese made with Lactobacillus rhamnosus_p1. Lactic acid bacteria were isolated from Gouda cheese ripened for more than 1 year. They were identified as 2 strains of L. rhamnosus, Lactobacillus casei, Lactobacillus curvatus, and Staphylococcus saprophyticus by 16S rDNA sequencing and named L. rhamnosus_p1, L. casei_p2, L. curvatus_p3, L. rhamnosus_p4 and S. saprophyticus_p5. The proteolytic activities of isolated strains against casein were measured using prepared skim milk agar plates. L. rhamnosus_p1 showed the highest proteolytic activity. Cutting-Gouda cheese was made with L. rhamnosus_p1, and its physicochemical properties (moisture, protein, fat, ash and free amino acid content) were measured during ripening periods. Because of the modified atmosphere packaging ($N_2{^-}$), there was no change in moisture, protein, fat, and ash in the experimental group. The total amount of free amino acids in the control and experimental group gradually increased during ripening periods. The sensory evaluation showed that the experimental group was preferable to the control group. This result suggests that L. rhamnosus_p1 has potential to be developed as a new starter for Gouda cheese.

• Childhood Kidney Diseases
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• v.9 no.2
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• pp.175-182
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• 2005

Purpose : Interleukin 1 receptor antagonist(IL-1ra) is an endogenous antiinflammatory agent that binds to IL-1 receptor and thus competitively inhibits the binding of IL-1$\alpha$ and IL-1$\beta$. Allele 2 in association with various autoimmune diseases has been reported. In order to evaluate the influence of IL-1ra gene VNTR polymorphism on the susceptibility to HSP and its possible association with disease severity, manifested by severe renal involvement and renal sequelae, we studied the incidence of carriage rate and allele frequency of the 2 repeats of IL-1ra allele 2($IL1RN^{*}2$) of the IL-1ra gene in children with HSP with and without renal involvement. Methods : The IL-1ra gene polymorphisms were determined in children with HSP with(n=40) or without nephritis(n=34) who had been diagnosed at Busan Paik Hospital and the control groups(n=163). Gene polymorphism was identified by PCR amplification of the genomic DNA. Results : The allelic frequency and carriage rate of $IL1RN^{*}1$ were found most frequently in patients with HSP and in controls. The allelic frequency of $IL1RN^{*}2$ was higher in patients with HSP compared to that of controls($4.7\%\;vs.\;2.5\%$, P=0.794). The carriage rate of $IL1RN^{*}2$ was higher In patients with HSP compared to that of controls($8.1\%\;vs.\;6.8\%$, P=0.916). The allelic frequency of $IL1RN^{*}2$ was higher in patients with HSP nephritis compared to that of HSP($5.3\%\;vs.\;2.9\%$, P=0.356). The carriage rate of $IL1RN^{*}2$ was higher in Patients with HSP nephritis compared to that of HSP($10.0\%\;vs.\;5.9\%$, P=0.523). Among 13 patients with heavy proteinuria(>1.0 g), 11 had $IL1RN^{*}1$, 1 had $IL1RN^{*}2$ and the others had $IL1RN^{*}4$. At the time of last follow up 4 patients had sustained proteinuria and their genotype was $IL1RN^{*}1$. Conclusion : The allelic frequency and carriage rate of $IL1RN^{*}1$ were found most frequently in patients with HSP and in controls. Our study suggests that the carriage rate and allele frequency of the 2-repeats of IL-1lra allele 2($IL1RN^{*}2$) of the IL-1ra gene may not be associated with susceptibility and severity of renal involvement in children with HSP (J Korean Soc Pediatr Nephrol 2005;9:175-182)

• 한국균학회소식:학술대회논문집
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• 2015.05a
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• pp.55-55
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• 2015

Rust is one of the most destructive diseases on economically important plants such as agricultural and horticultural crops, as well as forest trees [1]. Chemical treatment is the most effective means to control rust, but use of the chemical fungicides involves inevitable risks to human health and environment [2]. Unfortunately, biocontrol is currently impracticable for rust disease management [3]. It is necessary to exploit biocontrol agents to help prevent rust diseases. As a fundamental research for future development of biocontrol agents for rusts, biodiversity of hyperparasites occurring on rust fungi was investigated. During 2006-2010, 197 fungal isolates of the rust hyperparasites were collected and isolated from various combinations of mycohosts and plant hosts in many regions of Korea. Based on morphological and molecular data, they were identified as 8 genera and 12 species. Besides, phylogenetic relationships between the hyperparasites and related taxa were inferred. A total of 114 isolates of Pseudovirgaria were obtained from rust pustules of Phragmidium spp. and Pucciniastrum agrimoniae infecting rosaceous plants. Phylogenetic analysis using multigene sequences revealed a high level of genetic variability among many isolates of Pseudovirgaria and close correlation between the isolates and mycohosts. Only two species of Pseudovirgaria, P. hyperparasitica and P. grisea are often difficult to distinguish by their morphological similarity, but on the molecular basis they were clearly differentiated from each other. There had been no previous record of P. grisea outside Europe, but the present study has proved its presence in Korea. Among six distinct groups (five of P. hyperparasitica and one of P. grisea) within the Pseudovirgaria isolates, each lineage of P. hyperparasitica was closely associated with specific mycohosts and thus might have cospeciated with their mycohosts, which probably led to coevolution. Although P. grisea possesses a host preference for Phragmidium species occurring on Rubus, it was not specific for a mycohost. P. grisea seems to evolve in the direction of having a broad mycohost range. Seventeen isolates of Verticillium-like fungi were isolated from rust sori. Based on morphological data and DNA sequence analysis, the isolates were identified as three Lecanicillium species, viz. L. attenuatum, Lecanicillium sp. 1, Lecanicillium sp. 2, and V. epiphytum. The unidenified two species of Lecanicillium appear to be previously unknown taxa. Sixty-six isolates of miscellaneous hyphomycetes belonging to 6 species of 5 genera were obtained from pustules of rust fungi. On the basis of morphological and molecular analyses, the miscellaneous hyphomycetes growing on rusts were identified as Acrodontium crateriforme, Cladophialophora pucciniophila, Cladosporium cladosporioides, Phacellium vossianum, Ramularia coleosporii, and R. uredinicola.

• Journal of Animal Science and Technology
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• v.54 no.2
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• pp.133-139
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• 2012

A bacterium, identified as $Bacillus$ $amyloliquefacies$, CNL-90 using 16S rDNA analysis, was isolated from malt grain. The optimal activities of its ${\alpha}$-amylase and protease were observed at pH 6 and $60^{\circ}C$, and at pH 6 and $50^{\circ}C$, respectively although their activities remained stable at pH 7 and $40^{\circ}C$for ${\alpha}$-amylase and at pH 7 and $50^{\circ}C$ for protease. After solid-state fermentation of $B.$ $amyloliquefacies$, CNL-90 on wheat bran for 72hr or 144hr, the ${\alpha}$-amylase and protease activities were 170,000 and 290,000 units/kg, and 290,000 and 310,000 units/kg, respectively. The viable bacterial cell counts were $1.5{\times}10^9$ CFU/g and $2.2{\times}10^9$ CFU/g at 72hr and 144hr of the solid-state fermentation, respectively. A feeding trial with a total of 127 piglets was also conducted. The animals were divided into two groups: an experimental group fed with the fermented product (63 piglets) and a control group (64 piglets). The growth rate of the experimental group was 6.66% higher than that of the control group (P<0.05). The results of this study indicate that the ${\alpha}$-amylase and protease from $B.$ $amyloliquefacies$, CNL-90 can be used for industrial applications due to their activity in production of carbohydrate hydrolysates.

• KSBB Journal
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• v.29 no.5
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• pp.316-322
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• 2014

Xylanase have been used to convert the polymetric xylan into fermentable sugars from the production of ethanol and xylitol from plant biomass. The aim of this study was to isolate and identify xylanolytic bacterium from herbivore feces and was to used the xylanase for enzymatic hydrolysis of biomass. Xylanolytic strains were isolated from 59 different feces of herbivores from Seoul Grand Park located in Gwacheon Gyeonggi-do. The xylanolytic strains were selected by congo red staining and DNS method. Total 67 strains isolated from the herbivores feces were tested for xylanase activity. Among the strains, H10-1, which has the highest xylanase activity, was isolated from feces of Ceratotherium simum. The H10-1 strain was identified as Bacillus pumilus based on its morphological/biochemical characteristics and partial 16S rDNA gene sequences. Culture conditions of B. pumilus H10-1 such as initial medium pH, incubation temperature and incubation time were optimized for maximum xylanase production. And also xylanase produced by B. pumilus H10-1 was applied for the saccharification of Miscanthus sacchariflorus cv. 'Geodae 1', which was pretreated with 1.5M NaOH. The optimized culture conditions of B. pumilus H10-1 were pH 9, $30^{\circ}C$ incubation temperature, and 7 day incubation time, respectively. This xylanase activity under the optimized conditions was $20.4{\pm}3.3IU$. The crude xylanase produced by B. pumilus H10-1 was used for the saccharification of xylan derived from pretreated 'Geodae 1'. The saccharification conditions were $50^{\circ}C$, 200 rpm, and 5 days. Saccharification efficiency of pretreated 'Geodae 1' by B. pumilus H10-1 was 8.2%.

• Food Science of Animal Resources
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• v.37 no.5
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• pp.735-742
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• 2017

This study was conducted to isolate and characterize Paenibacillus sp. MBT213 possessing ${\beta}$-glucosidase activity from raw milk, and examine the enzymatic capacity on the hydrolysis of a major ginsenoside ($Rb_1$). Strain MBT213 was found to have a high hydrolytic ability on ginsenoside $Rb_1$ by Esculin Iron Agar test. 16S rDNA analysis revealed that MBT213 was Paenibacillu sp. Crude enzyme of MBT213 strain exhibited high conversion capacity on ginsenoside $Rb_1$ into ginsenoside Rd proven by TLC and HPLC analyses. The API ZYM kit confirmed that Paenibacillu sp. MBT213 exerted higher ${\beta}$-glucosidase and ${\beta}$-galactosidase activity than other strains. Optimum pH and temperature for crude enzyme were found at 7.0 and $35^{\circ}C$ in hydrolysis of ginsenoside $Rb_1$. After 10 d of optimal reaction conditions for the crude enzyme, ginsenoside $Rb_1$ fully converted to ginsenoside Rd. Ginseng roots (20%) were fermented for 14 d, and analyzed by HPLC showed that amount of ginsenoside $Rb_1$ significantly decreased, while that of ginsenoside Rd was significantly increased. The study confirmed that the ${\beta}$-glucosidase produced by Paenibacillus sp. MBT213 can hydrolyze the major ginsenoside $Rb_1$ and convert to Rd during fermentation of the ginseng. The ${\beta}$-glucosidase activity of this novel Paenibacillus sp. MBT213 strain may be utilized in development of variety of health foods, dairy foods and pharmaceutical products.

• Microbiology and Biotechnology Letters
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• v.48 no.1
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• pp.57-63
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• 2020

Over the past 20 years, global warming has transformed the marine ecosystem of the Jeju Island into a subtropical zone making it conducive to the production of tropical fishes. Recently, the balloon fish (Diodon holoanthus) has been found off the coast of the Jeju Island. In this study, we analyzed the diversity of its intestinal microorganisms as a representative for the surrounding environment. In addition, the isolates were evaluated for their antibacterial activity. A total of 161 strains of various species were identified and isolated using 16S ribosomal RNA gene sequence analysis. They were separated into three groups, of which Phylum Proteobacteria was found to be the most dominant with 91% sequence similarity. This includes the class γ-proteobacteria that is made up of twelve genera and twenty-four hundred species. The second group comprised strains of the genus Vibrio, made up of 35% Photobacteria, 32% Shewanella, and 6% Psychrobacter. It was also determined that 4% of the isolates were Acinetobacter, 3% were Enterovibrio, while Moraxella_g2 accounted for 1% of the total isolates. Class α-proteobactera includes five genera and five species; Brevundimonas, Allorhizobium, Pseudoceanicola and Erythrobcter, each accounting for 1% of the total isolates. The Firmicute strains belonged to six genera and ten species. 5% of the strains were Terribacillus, while Paenibacillus, Salinicoccus, Staphylococcus and Streptococcus accounted for 1% each of the total isolates. Actinobacteria accounted for the final phylum with strains belonging to three genera and ten species with Janibacter, Micrococcus and Isoptericola each accounting for 1% of the total isolates.

• The Plant Pathology Journal
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• v.25 no.1
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• pp.86-90
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• 2009

In November 2008, typical powdery mildew symptoms were observed on leaves of Arabidopsis thaliana ecotype Col-0 plants in a growth room under controlled laboratory conditions at Korea University, Seoul. The disease was characterized by the appearance of white powder-like fungal growth on the surface of infected leaves. As the disease progressed, infected leaves exhibited chlorotic or necrotic brown lesions, and leaf distortion and senescence. Conidiophores of the causal fungus were hyaline, unbranched, 3-4 celled, cylindrical, and $80-115{\times}6-9{\mu}m$ in size. Singly produced conidia (pseudoidium type) were hyaline, oblong to cylindrical or oval in shape, and $26-55{\times}15-20{\mu}m$ in size with a length/width ratio of average 3, angular/rectangular wrinkling of outer wall and no distinct fibrosin bodies. Appressoria on the hyphae were multi-lobed. These structures are typical of the powdery mildew Oidium subgenus Pseudoidium, anamorph of the genus Erysiphe. The measurements of the fungal structures coincided with those of Erysiphe cruciferarum. The phylogenetic analysis using ITS rDNA sequences revealed that the causal fungus Erysiphe sp. KUS-F23994 is identical to E. cruciferarum. The isolated fungus incited powdery mildew symptoms on the inoculated Arabidopsis leaves, which proved Koch's postulates. Taken all data together, we first report the occurrence of powdery mildew disease of A. thaliana caused by Erysiphe cruciferarum in Korea.

• Research in Plant Disease
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• v.21 no.1
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• pp.36-39
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• 2015

In June 2012 and 2013, a destructive stem rot symptoms of Ligularia fischeri occurred sporadically in Hoengseong-gun and Pyeongchang-gun Gangwon-do, Korea. The typical symptom included water-soaking on the main stem, rotting, wilting and blighting, which eventually leads to death of the plant. White mycelial mats were spread over lesions and brown sclerotia were formed on stems and near soil surface. The sclerotia were white to brown, spherical or irregular, 1-3 mm in size on potato dextrose agar (PDA), The optimum temperature range of hyphal growth was $25-30^{\circ}C$ and the hyphal diameter was $4-10{\mu}m$. The typical clamp connections were observed in the hyphae of the fungus grown on PDA. The resulting sequence of 695 bp was deposited in GenBank. A BLAST search revealed that sequences of the this isolates showed >99% identity with those of Sclerotium rolfsii. On the basis of the morphological characteristics and phylogenetic analyses of molecular markers ITS rDNA, the fungi were identified as S. rolfsii. A pathogenicity test was carried out to fulfill Koch's postulates. To our knowledge, this is the first report of S. rolfsii on Ligularia fischeri in Korea.