• Journal of Food Hygiene and Safety
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• v.15 no.2
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• pp.128-136
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• 2000

Twenty-four Vibrio strains were isolated from imported frozen seafoods and identified according to their physiological and biochemical properties. They included two V cholerae non-01 sp., two V. diazotrophicus sp., one V. hollisae sp., five V. natriegens sp., eight V. fluvialis sp., and four V. nereis sp.. Two of them were not identified as Vibrio species. When these strains were tested using API-2OE kit fur identification, however, only the results for two V. cholerae and five of the V. fluvialis strains matched the results obtained previously. Due to the importance of detecting V cholerae from foods, phylogenetic identification of the strains was attempted based on restriction fragment length polymorphism (RFLP) of the 16S rDNAs amplified by PCR. The results suggested that the two strains had identical RFLP patterns which were more closely related to that of V. proteolyticus than V. cholerae. The problems associated with identification of pathogens originated from seafoods demand development of accurate and rapid identification methods.

• Korean Journal of Medicinal Crop Science
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• v.11 no.4
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• pp.311-315
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• 2003

This study was carried out to compare chromosomal characteristics between Atractylodes japonica and A macrocephala. Cytogenetic analysis was conducted based on karyotype analysis and physical mapping using fluorescence in situ hybridization. As a result of karyotype analysis by feulgen staining, somatic chromosome numbers of A. japonica and A. macrocephala were 2n=24. The length. of the mitotic metaphase chromosomes of A. japonica ranged from $0.70\;to\;1.60{\mu}m$ with a total length. of $12.11{\mu}m$ and the homologous chromosome complement comprised six metacentrics, five submetacentrics and one subtelocentrics. On the other hand, the length of the mitotic metaphase chromosomes of A. macrocephala ranged from $0.90\;to\;2.35{\mu}m$ with a total length of $16.58{\mu}m$ and the homologous chromosome complement comprised seven metacentrics and five submetacentrics. The total length of A. japonica chromosomes was shorter than that of A. macrocephala, but A. japonica had one subtelocentrics (chromosomes 4) different from A. macrocepha1a. chromosomes. The F1SH technique using 17S and 5S rDNA was applied to metaphase chromosomes. The signals for 17S rDNA were detected on the telomeric regions of chromosomes 4 and 5 in both A japonica and A. macrocephala. The 5S rDNA signal was found in the short arm of chromosome 1.

• Korean journal of applied entomology
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• v.39 no.1
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• pp.5-12
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• 2000

The sweetpotato whiteflies, Bemisia tabaci(Gennadius), were found recently in Korea on Glycine max, Euphorbia pulcherrima, and Rosa hybrida. The biotype identity of Bemisia tabaci in Korea was determined by several DNA markers including the random amplified polymorphic DNAs, and restriction fragments length polymorphism of mitochondrial 12S and 16S rRNA genes. The electromorph profiles of DNA fragments from the rose(Jincheon) and poinsettia(Seoul) populations in Korea are both identical to those of B biotypes distributed in Australia, Israel, and Japan. The populations of B. tabaci collected on Glycine max, Ipomea batatas, and Perilla frutescens in different localities retained the same DNA markes with the population from Lonicera japonica and shikoku of Japan. These populations are non-B biotype and considered as an indigenous type in the Far Eastern Asia Region including Korea and Japan, Morphological Characteristics of B. Tabaci were also observed by the scanning electron microscope and described with the comparison to the other important whitefly pest, Trialeurodes vaporariorum (Westwood).

• International Journal of Oral Biology
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• v.43 no.1
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• pp.5-11
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• 2018

Recent findings indicate that Type 2 taste receptors (T2Rs) are expressed outside the gustatory system, including in the gastrointestinal tracts and the exocrine glands, such as the submandibular (SM), parotid (P), lacrimal (L) glands and pancreas (PC). Specifically, T2Rs are found in some of the gastrointestinal endocrine cells, and these cells secreted peptide hormones in response to stimulation by bitter-tasting compounds. The results show that T2Rs may have significant physiological roles besides bitter taste reception. The functions of the T2Rs in the exocrine glands remain poorly understood. An expression levels analysis of T2Rs will help to determine those functions in the exocrine glands. The expression levels of the T2Rs in the exocrine glands were discovered via the qPCR. C57BL/6J mice of 42~60-day-old were used. Messenger RNAs were extracted from S, P, L and PC. Cloned DNAs were synthesized by reverse transcription. Quantitative PCRs were performed using the SYBR Green method. The expression levels of the T2Rs were calculated as relative expression levels to that of the GAPDH. The statistical significance among the observed exocrine glands was tested using the variance analysis (ANOVA test). Tas2r108, out of murine 35 T2Rs, was the most highly expressed in every observed exocrine gland. This finding was similar to previous results from tongue papillae, but the expression levels were lower than those of the tongue papillae. Tas2r137 of SM, P, L and PC were expressed a little lower than that of tongue papillae. The T2Rs in the exocrine glands may play slightly different roles from those in the tongue. We suggest that physiological studies such as a patch clamp and functional $Ca^{2+}$ imaging of acinar cells are necessary for understanding the Tas2r108 functions.

• Food Science of Animal Resources
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• v.25 no.2
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• pp.203-209
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• 2005

Real time-polymerase chain reaction (RT-PCR) is currently considered as the most sensitive method to detect low abundant DNAs in samples. Compared to conventional PCR, real-time PCR has a high reliability because of excluding false-positive results and can allow a simultaneous faster detection and quantification of target DNAs. This study was carried out to identify the Hanwoo (Korean native cattle) beef by genotyping after DNA extraction of commercial beef in 41 restaurants. Since Hanwoo, Holstein and imported cattle meat have different patterns in the MC1R gene associated with the coat colors of cattles (C-type, C/T-type or T-type), we could identify the genotype using real-time PCR The result of real-time PCR assay for beef samples in 41 restaurants which are asserted to sell Hanwoo beef only, showed that 29 of 41 samples were Hanwoo beef gene type (T-type) and 12 of 41 samples were Holstein or imported cattle gene type (C-type or C/T-type). Therefore, the proportion of Han-woo beef was $70.7\%$ and the proportion of Holstein or imported cattle meat was $29.3\%(C/T-type; 12.2\%,\;C-type; 17.1\%)$.

• Parasites, Hosts and Diseases
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• v.62 no.2
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• pp.180-192
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• 2024

Free-living amoebae (FLA) are found in diverse environments, such as soils, rivers, and seas. Hence, they can be used as bioindicators to assess the water quality based solely on their presence. In this study, we determined the presence of FLA in river water by filtering water samples collected from various sites and culturing the resulting filtrates. FLA were detected in all the water samples with varying quality grades (Grades I-V). The significant increase in the size of the amoebae population with the deterioration in the water quality. Monoxenic cultures of the amoebae were performed, and genomic DNAs were isolated, among which 18S rDNAs were sequenced to identify the amoeba species. Of the 12 species identified, 10 belonged to the Acanthamoeba genus; of the remaining 2 species, one was identified as Vannella croatica and the other as a species of Vermamoeba. Acanthamoeba was detected in samples with Grades I to VI quality, whereas the Vermamoeba species was present only in Grade I water. V. croatica was found exclusively in water with Grade II quality. Following morphological observations, genomic DNA was sequenced using 16S rDNA to determine whether the species of Acanthamoeba harbored endosymbionts. Most of the isolated Acanthamoeba contained endosymbionts, among which 4 species of endogenous bacteria were identified and examined using transmission electron microscopy. This study provides evidence that the distribution of amoebae other than Acanthamoeba may be associated with water quality. However, further confirmation will be required based on accurate water quality ratings and assessments using a more diverse range of FLA.

• Journal of Mushroom
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• v.13 no.1
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• pp.79-83
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• 2015

In this study, SCAR marker that differentiates Pleurotus eryngii strains with higher ${\beta}$-glucan from control strain was developed. Genomic DNAs of 9 control strains of Pleurotus eryngii and 9 Pleurotus eryngii strains with higher ${\beta}$-glucan were analyzed by bulked segregant analysis (BSA) using randomly amplified polymorphic DNA (RAPD). One-hundred twenty RAPD primers were screened on bulked DNA samples and a unique DNA fragment with the size of 91 bp was yielded by OP-R03 primer from the Pleurotus eryngii strains with higher ${\beta}$-glucan. A sequence characterized amplified region (SCAR) marker, designated as OP-R03-1-F and OP-R03-1-R, was designed on the basis of the determined sequence. The PCR analysis with the OP-R03-1 primer showed that this SCAR marker can clearly distinguish the Pleurotus eryngii strains with higher ${\beta}$-glucan from the control strains.

• Journal of Microbiology and Biotechnology
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• v.20 no.2
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• pp.245-253
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• 2010

The base sequences representing human- and cow-specific 168 rRNA gene markers identified in a T-RFLP analysis were recovered from clone libraries. The human- and cow-specific primers were designed from these sequences and their specificities were analyzed with fecal DNAs from human, cow, and pig. The AllBac primer set showed positive results for all human, cow, and pig samples, whereas the human-specific primer set showed positive result only for the human sample but not for the cow or pig samples. Likewise, the cow-specific primer set showed positive results only for the cow sample but not for the human or pig samples. Real-time PCR assay with these primers was developed for the identification and quantification of fecal pollution in the river water. The human- and cow-specific markers were detected in the order of 9 $\log_{10}$ copies per gram wet feces, which were two orders of magnitude lower than those of total Bacteroidales. For the river water samples, the human-specific marker was detected in $1.7-6.2\;\log_{10}$ copies/100 ml water, which was 2.4-4.9 orders of magnitude lower than those of total Bacteroidales. There was no significant correlation between total Bacteroidales and conventional fecal indicators, but there was a high correlation between Bacteroidales and the human-specific marker. This assay could reliably identify and quantify the fecal pollution sources, enabling effective measures in the watersheds and facilitating water quality management.

• Advances in Traditional Medicine
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• v.5 no.2
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• pp.117-123
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• 2005

Dyers woad leaf (Daqingye) is a traditional Chinese medicine commonly used as anti-pyretic, anti-bacterial and anti-viral agent against infectious diseases. The Chinese Pharmacopoeia (2005) records that Dyers woad leaf should be derived from the leaves of Isatis indigotica Fort., but the leaves of Polygonum tinctorium Ait., Baphicacanthus cusia (Nees) Bremek. and Clerodendron cyrtophyllum Turcz. have also been used as substitutes of Dyers woad leaf in different regions of China. The leaf morphologies of these four species show a close resemblance, and based on their morphological appearance, it is difficult to identify them. Here, molecular genetic methods were developed as a target to identify different members of Dyers woad leaf. The 5S-rRNA spacer domain was amplified by polymerase chain reaction from genomic DNAs isolated from I. indigotica, P. tinctorium, B. cusia and C. cyrtophyllum, and the nucleotide sequences showed a great diversity. In addition, random amplification of polymorphic DNA analysis was also used to distinguish the members of Dyers woad leaf. These molecular methods could be used as a tool in authentic identification of Dyers woad leaf.

• Korean Journal of Microbiology
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• v.35 no.3
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• pp.173-179
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• 1999

As a result of PCR-RFLP, the isolates used in this study were classified into five groups. Isolates 1 and 3 were included in AG-5 with 97% genetic similarity. Isolates 12 and 13 were included in AG-1 wilh 100% genetic similarily. Isolates 10 and AG-2-2 showed 97% similarity Isolates 7, 8, 11. 13, and 15 were included in AG-1. When isolates of 4, 5, 7 and 8 were restricted with Hae I. there was a single 700 bp fragment matched with AG-1. A 517 bp restriction fragment of isolate 9 was matched with AG-2-1. Based on the result of southem hybridization of genomic DNAs, all isolates restricted with Msp I showed more variable restriction differences than those restricted with Hae Ill. Isolates AG-2-1 and 9 showed 200 bp restriction fragment, and isolates 3 and AG-1 showed 1 kb restriction fragments.