• Korean Journal of Microbiology
• /
• v.46 no.2
• /
• pp.169-176
• /
• 2010

A pilot-scale wastewater treatment plant combined with rotating biological contactor and tapered aeration reactors was operated with the wastewater discharged from a food factory for 5 months. The bacterial communities of this plant were investigated by terminal restriction fragment length polymorphism (T-RFLP) and phylogenetic analysis of 16S rRNA genes. In spite of high concentration of nitrogen and phosphorus as well as organic carbon, removal efficiency of chemical oxygen demand, total nitrogen, and total phosphorus was 98%, 93%, and 95%, respectively. Bacterial community at the initial operation stage was clearly distinguished from that of the stable operation stage. The most predominant phylum in the sample of stable stage was Bacteroidetes. Major population of operation period was Haliscomenobacter, Sphaerotilus, and candidate division TM7, which were classified as filamentous bacteria. However, sludge bulking caused by these bacteria was not observed. The population that has a close relationship with Haliscomenobacter increased during the stable operation stage, emerging as the most predominant group. These results suggest that the filamentous bacteria participated in nutrient removal when using rotating biological contactor and tapered aeration reactor.

• Clinical and Experimental Pediatrics
• /
• v.53 no.3
• /
• pp.397-407
• /
• 2010

Purpose : The F9 gene is known to be the causative gene for hemophilia B, but unfortunately the detection rate for restriction fragment length polymorphism-based linkage analysis is only 55.6%. Direct DNA sequencing can detect 98% of mutations, but this alternative procedure is very costly. Here, we conducted multiplex polymerase chain reactions (PCRs) and conformation sensitive gel electrophoresis (CSGE) to perform a screened DNA sequencing for the F9 gene, and we compared the results with direct sequencing in terms of accuracy, cost, simplicity, and time consumption. Methods : A total of 27 unrelated hemophilia B patients were enrolled. Direct DNA sequencing was performed for 27 patients by a separate institute, and multiplex PCR-CSGE screened sequencing was done in our laboratory. Results of the direct DNA sequencing were used as a reference, to which the results of the multiplex PCR-CSGE screened sequencing were compared. For the patients whose mutation was not detected by the 2 methods, multiplex ligation-dependent probe amplification (MLPA) was conducted. Results : With direct sequencing, the mutations could be identified from 26 patients (96.3%), whereas for multiplex PCRCSGE screened sequencing, the mutations could be detected in 23 (85.2%). One patient's mutation was identified by MLPA. A total of 21 different mutations were found among the 27 patients. Conclusion : Multiplex PCR-CSGE screened DNA sequencing detected 88.9% of mutations and reduced costs by 55.7% compared with direct DNA sequencing. However, it was more labor-intensive and time-consuming.

• Korean journal of applied entomology
• /
• v.53 no.1
• /
• pp.85-91
• /
• 2014

In this study, we analyzed the phylogenetic characterization of root-knot nematodes (Meloidogyne spp.) in soils from fruits and vegetables greenhouses in Korea. Soil samples were collected from 12 greenhouse fields in which tomato, cucumber, watermelon, and Oriental melon were being cultivated. Meloidogyne spp. were detected in all the soil samples at an average number of $72{\pm}6$ nematodes/300 g of soil to $2,898{\pm}468$ nematodes/300 g of soil. Phylogenetic analysis using polymerase chain reaction-restriction fragment length polymorphism was attempted for the second-stage juveniles (J2) of Meloidogyne spp. collected from the greenhouse soils. Twelve Meloidogyne spp. from the greenhouse soils were classified into two groups by using HinfI digestion of mitochondrial DNA, resulting in 900, 410, 290, and 170 bp fragments (group A) and 900, 700, and 170 bp fragments (group B). Phylogenetic analysis based on mitochondrial DNA sequences (1,483-1,521 bp) showed that nine group A isolates were identified as Meloidogyne incognita (99.73-99.93%) and three group B isolates showed 99.54-99.73% similarity to Meloidogyne arenaria.

• Korean journal of applied entomology
• /
• v.46 no.2
• /
• pp.175-182
• /
• 2007

Two fruit moths of the oriental fruit moth, Grapholita molesta (Busck), and the peach fruit moth, Carposina sasakii (Matsumura), infest apples in Korea by internally feeding behavior. C. sasakii is a quarantine insect pest from some other countries importing Korean apples. G. molesta is not a quarantine insect pest, but can be incorrectly identified as C. sasakii especially when it is found inside apple fruits at its larval stages because it is not easy to identify the two species by morphological characters alone. This incomplete identification results in massive economical loss by fruits needlessly destroyed or turned away at border inspection stations of the importing nations. This difficulty can be overcome by molecular DNA markers. Several polymorphic regions of mitochondrial DNA of both species were sequenced and used for developing specific striction sites and polymerase chain reaction (PCR) primers. Based on these sequences, three diagnostic PCR-restriction fragment length polymorphism (RFLP) sites were detected and validated for their practical uses. Also, species-specific PCR primers were devised to develop diagnostic PCR method for identifying the internal feeders.

• Clinical and Experimental Reproductive Medicine
• /
• v.30 no.4
• /
• pp.325-331
• /
• 2003

Objective: To investigate the association of genetic background between MTHFR A1298C genotype and male infertility. Materials and Methods: We compared 377 infertile males with 396 healthy fertile males with one or more offspring. Infertile males were classified into four subtypes (281 azoospermia, 26 oligoasthenoteratozoospermia (OAT), 59 severe OAT and 11 remnants) by World Health Organization (WHO). Pyrosequencing analysis for MTHFR (methylenetetrahydrofolatereductase) A1298C variation was performed on polymerase chain reaction (PCR) product of study group. To validate pyrosequencing data of A1298C variation for randomly selected 50 samples, we compared the pyrosequencing result with the PCR-RFLP (Restriction Fragment Length Polymorphism) result of MTHFR A1298C genotype. Results: We studied MTHFR A1298C variation by pyrosequencing. A1298C variation data (1298 AC; p=0.2166 and 1298 CC; p=0.5056) of MTHFR gene was no significant difference in between fertile and infertile males. Conclusion: The genetic analysis in MTHFR gene didn't appear genetic difference in Korean fertile and infertile males. We require further study for MTHFR gene in infertile males.

• Korean Journal of Food Science and Technology
• /
• v.47 no.2
• /
• pp.204-210
• /
• 2015

Makgeolli is made from rice or flour, yeast, and nuruk, a fermentation starter. The flavor of makgeolli is affected by sugars, amino acids, organic acids and volatile flavor compounds produced by various microorganisms. In this study, lactic acid bacteria (LAB) were isolated from unsterilized makgeolli samples collected from several provinces in Korea, and then later identified. Under anaerobic conditions, LAB density ranged from $5.0{\times}10^6$ to $1.5{\times}10^8CFU/mL$; yeast density ranged from $2.5{\times}10^7$ to $1.5{\times}10^8CFU/mL$. Of the LAB isolated from makgeolli, 1,126 were analyzed using restriction fragment length polymorphism (PCR-RFLP) analysis of 16S rRNA, which allowed for classification into five groups. Of the 1,126 LABs tested, 130 produced ${\gamma}$-aminobutyric acid (GABA).

• Journal of Microbiology
• /
• v.45 no.3
• /
• pp.246-255
• /
• 2007

Mutans streptococci have been implicated as cariogenic bacteria in dental caries because they can produce high levels of dental caries-causing lactic acid and extracellular polysaccharide. The aim of this study was to isolate and characterize the mutans streptococci from the dental plaque obtained from Koreans. The dental plaque samples were collected from the anterior and molar teeth of both jaws in 155 subjects (aged 2 to 33.2 years, average age $13.7{\pm}4.7\;years$). The samples were diluted by 100-fold in $1{\times}\;PBS$ and plated on mitis-salivarius bacitracin (MSB) agar plates. The mutans streptococci grown on MSB plates were screened by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) targeting dextranase gene (dex). The mutans streptococci were identified at the species level using a 16S rDNA sequencing comparison method. The biochemical tests were carried out to biotype the mutans streptococci. Ninety-five strains of the mutans streptococci out of 358 colonies, which were derived from 141 subjects, were isolated. Of them, 77 strains and 18 strains were Streptococcus mutans and Streptococcus sobrinus, respectively. The biotyping data showed that 62, 1, 20, 10, and 2 strains were biotypes I, II, IV, V and variant, respectively. Of the two strains of variant biotype, one strains was similar to biotype IV except that it was positive to the arginine hydrolysis test. We considered this one strain a new biotype, and classified it as biotype VII. In conclusion, S. mutans and its biotype I was most frequently isolated in Korean dental plaque. The mutans streptococci strains isolated in this study might be useful for the study of the pathogenesis and the prevention of dental caries.

• Applied Biological Chemistry
• /
• v.47 no.2
• /
• pp.182-186
• /
• 2004

Morphological observation of roots and molecular technique were used to investigate the symbiotic relationships between arbuscular mycorrhizal (AM) fungi and ginseng roots. Korean ginseng, Panax ginseng, was collected from 8 sites in Korea. Colonization pattern of AM fungi in ginseng roots was determined as an Arum type under light microscopes. Nested PCR using AM fungal specific primers was employed to amplify a partial region on 18s rDNA of AM fungi from the root extracted mixed DNA. The amplified DNA was cloned and analyzed by random fragment length polymorphism (RFLP) with restriction enzymes, AluI, HinfI and AsuC21. One from each RFLP pattern was selected for sequencing. A total 16 clones were sequenced and identified as 2 species of AM fungi; Paraglomus brasilianum and Glomus spurcum. Paramglomus brasilianum was found from most of the ginseng roots, in this syudy suggesting that this species of AM fungi could have specific relationship with the ginseng root. Possible roles of AM fungal species in ginseng roots are discussed.

• Journal of Life Science
• /
• v.17 no.12
• /
• pp.1622-1626
• /
• 2007

This study was conducted to identify useful single nucleotide polymorphisms (SNPs) and determine their association with economically important traits in pig population. Four candidate gene analyses have identified important chromosomal regions and major genes associcated whit economic traits of the pig. For application of the chromosomal information to the pig industry using DNA technology, SNP markers were developed by comparative re-sequencing of polymerase chain reaction (PCR) products of 4 candidate genes (CSF2, IL4, MYOD, RIP140). PCR restriction fragment length polymorphism (PCR-RFLP) assays were developed for these 4 SNPs and used to genotype Berkshire pig populations in Korea.

• Clinical and Experimental Reproductive Medicine
• /
• v.44 no.3
• /
• pp.152-158
• /
• 2017

Objective: To identify the associations between polymorphisms of the 3'-untranslated region (UTR) of methylenetetrahydrofolate reductase (MTHFR) gene, which codes for an important regulatory enzyme primarily involved in folate metabolism, and idiopathic recurrent pregnancy loss (RPL) in Korean women. Methods: The study population comprised 369 RPL patients and 228 controls. MTHFR 2572C > A, 4869C > G, 5488C > T, and 6685T > C 3'-UTR polymorphisms were genotyped by polymerase chain reaction-restriction fragment length polymorphism analysis or by TaqMan allelic discrimination assays. Natural killer cell proportions were determined by flow cytometry. Results: The MTHFR 2572-5488-6685 (A-C-T) haplotype had an adjusted odds ratio of 0.420 (95% confidence interval, 0.178-0.994; p= 0.048) for RPL. Analysis of variance revealed that MTHFR 4869C > G was associated with altered $CD56^+$ natural killer cell percentages (CC, $17.91%{\pm}8.04%$; CG, $12.67%{\pm}4.64%$; p= 0.024) and folate levels (CC, $12.01{\pm}7.18mg/mL$; CG, $22.15{\pm}26.25mg/mL$; p= 0.006). Conclusion: Variants in the 3'-UTR of MTHFR are potential biomarkers for RPL. However, these results should be validated in additional studies of ethnically diverse groups of patients.