• Food Science and Biotechnology
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• v.17 no.2
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• pp.357-361
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• 2008

One of the major allergenic proteins in common buckwheat (Fagopyrum elculentum) was found to be a BW10KD. In this work, allergenic BW10KD genomic DNAs from the native common buckwheat 'Pyeongchang' and Tartarian buckwheat 'Clfa47' were cloned by polymerase chain reaction (PCR), and their nucleotide sequences were determined. In addition, a novel PCR assay targeting the allergenic BW10KD gene was developed to detect and differentiate both buckwheat species in food. The nucleotide sequences of the BW10KD genomic DNA from 'Pyeongchang' and 'Clfa47' were 94% identical. Base differences in the nucleotide sequences of the BW10KD genes are probably useful as a molecular marker for species-specific identification. The 'Pyeongchang'-specific primer set 154PF/400PR and the 'Clfa47'-specific primer set 154DF/253DR generated 247 and 100 bp fragments in singleplex PCR, respectively. A duplex PCR assay with 2 species-specific primer sets simultaneously differentiated the 'Pyeongchang' and 'Clfa47' in a single reaction. The PCR assay also successfully allowed for the rapid detection of buckwheat ingredients in foods.

• Food Science and Biotechnology
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• v.17 no.3
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• pp.651-654
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• 2008

In order to enhance the efficacy of norovirus detection by reverse transcriptase-polymerase chain reaction (RT-PCR) and nested PCR, this study developed a norovirus mRNA concentration method using poly oligo dT-conjugated magnetic beads. An efficient norovirus detection protocol was performed on commercial ham using 2 viral elution buffers (glycine buffer and Tris beef extract buffer) and 2 concentration solutions [polyethylene glycol (PEG) and zirconium hydroxide]. The different approaches were verified by RT-PCR and nested PCR. This method was performed on ham in less than 8 hr by artificial inoculation of serial dilutions of the virus ranging from 1,000 to 1 RT-PCR unit/mL. The viral extraction and concentration method had 10-fold higher sensitivity using the combination of Tris beef extract buffer and PEG as compared to glycine buffer and zirconium hydroxide. This method proved that RT-PCR and nested PCR have the sensitive ability to detect norovirus in commercial ham, in that norovirus was successfully detected in artificially contaminated samples at a detection level as low as 1-10 RT-PCR unit/mL. Overall, such a detection limit suggests this protocol is both quick and efficient in terms of its potential use for detecting norovirus in meat products.

• The Korean Journal of Food And Nutrition
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• v.22 no.4
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• pp.687-695
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• 2009

The present study attempted to offer more insights into the foreign consumers' consumption decision structure of Korean restaurants located in foreign countries. A survey was designed based on the means-end chain theory, using the laddering interview technique. The qualitative data obtained from 10 Americans, 10 Japanese, and 10 Chinese were content analyzed and resulted in categories such as 'new experience', 'interest in Korea', 'recommendation', 'good food', 'easy to access', 'service', 'dining environment', and 'price' as perceived attributes of choice. The hierarchical value maps linking attributes, psychological consequences, and terminal values were presented. The most frequent consequences were 'experience new culture', 'be exposed to new experience', and 'learn more about Korea' which were related to 'happiness', 'pleasure', 'good relationship', 'desire fulfillment', and 'self-satisfaction' as personal values. Laddering interviews, which required laborious analysis, provided important information on the relationship between perceived attributes and the reasons for choosing Korean restaurants.

• Journal of Microbiology and Biotechnology
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• v.9 no.2
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• pp.184-190
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• 1999

The use of the polymerase chain reaction (PCR) method was described using two sets of primers based on the ceuN gene (JEJ 1 and JEJ 2) which encodes a protein involved in siderophore transport and 16S rRNA gene (pA and pB) for the sensitive and specific detection of enteropathogen Campylobacter jejuni. Six oligonucleotides were utilized in an amplification experiment and PCR products of predicted sizes were generated from whole cells and boiled cell lysates at the same intensity. Two sets of the primer pairs, JEJ and pAB, were specific enough for all C. jejuni strains tested for the direct use of whole cells without DNA extraction or lysis steps. In the PCR using the pAB primer pair, the detection limit, as determined by the ethidium bromide staining of the amplification products on agarose gels, was at the level of $10^1$ bacteria cells or less in both the pure culture and artificially inoculated milk and chicken enrichment samples, whereas the detection limit with the JEJ primer pair was relatively low, i.e. $10^3$ cells or more in the same PCR samples. The PCR method using either a primer JEJ or pAB was both repeatable and specific for the detection of C. jejuni in food. This method is simply completed within 4 h.

• Journal of the Korean Society of Food Culture
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• v.4 no.3
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• pp.229-236
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• 1989

Fast food restaurants are growing in numbers in Korea since they were introduced abot a decade ago. To develop an effective marketing strategy for fast foods, it is important to assess consumer's acceptability and identify demorgraphic, environmental, and managerial factors which influence consumer's perception on the fast food restaurants. A total of 595 customers were surveyed at thirty hamburger chain restaurants in Seoul from November 7 to 15, 1988. Analyses of the collected data revealed that adolescents, females, and the people with high income were the major customers and visited more than once or twice a week; frequent visitors rated meals more favorably in terms of the quality, service and cleanliness, and they also rated meals of foreign brand more favorable than those of domestic one; the female group perceived the change in their dietary habits more than any other groups; cleanliness, convenience, atmosphere, courtesy, and the taste of foods were significant factors in purchasing fast foods; and customers were most satisfied with convenience, while least satisfied with the price and the quantity of foods. From these findings, it is sggested that the manager of the fast food restaurant must consider the consumer's perception of fast foods in terms of pros and cons in order to operate her/his restaurant successfully.

• Food Science and Biotechnology
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• v.18 no.3
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• pp.694-699
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• 2009

A multiplex polymerase chain reaction (PCR) method was developed for the detection of 4 events of genetically modified (GM) soybean. The event-specific primers were designed from 4 events of GM soybean (RRS, A2704-12, DP356043-5, and MON89788). The lectin was used as an endogenous reference gene of soybean in the PCR detection. The primer pair YjLec-4-F/R producing 100 bp amplicon was used to amplify the lectin gene and no amplified product was observed in any of the 9 different plants used as templates. This multiplex PCR method allowed for the detection of event-specific targets in a genomic DNA mixture of up to 1% GM soybean mixture containing RRS, A2704-12, DP356043-5, and MON89788. In this study, 20 soybean products obtained from commercial food markets were analyzed by the multiplex PCR. As a result, 6 samples contained RRS. These results indicate that this multiplex PCR method could be a useful tool for monitoring GM soybean.

• Journal of Life Science
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• v.17 no.11
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• pp.1511-1516
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• 2007

Basophils and mast cells play an important role in $Fc{\varepsilon}RI-mediated$ allergic reaction as effector cells. We studied the effects of Acanthopanax chiisanensis on $Fc{\varepsilon}RI\;{\alpha}$ chain expression in human basophilic KU812F cells. Ethanol extracts from root and stem of A. chiisanensis were tested for inhibitory effects of $Fc{\varepsilon}RI\;{\alpha}$ chain expression. The cell surface $Fc{\varepsilon}RI\;{\alpha}$ chain expression was examined by flow cytometric analysis. All of the extracts of A. chiisanensis reduced the cell surface $Fc{\varepsilon}RI\;{\alpha}$ chain expression. Furthermore, A. chiisanensis extracts caused a decrease in the level of $Fc{\varepsilon}RI\;{\alpha}$ chain mRNA level and $Fc{\varepsilon}RI-mediated$ histamine release. These results suggest that root and stem extracts of A. chiisanensis play an important role in anti-allergic activity via down-regulation of $Fc{\varepsilon}RI\;{\alpha}$ chain expression and decrease in release of inflammatory mediator such as histamine.

• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.10
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• pp.1452-1456
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• 2009

Fucoxanthin has been concentrated efficiently using supercritical carbon dioxide. First, fucoxanthin was extracted from Ecklonia cava using solvents. Three solvents, such as medium chain fatty acid (MCFA), medium chain fatty acid ethyl ester, and fatty acid from coconut oil were tested, and MCFA was selected as a suitable solvent to extract fucoxanthin from Ecklonia cava. The concentration was conducted at various pressures and temperatures. In order to concentrate fucoxanthin from extracts, MCFA was eliminated from the extract using supercritical carbon dioxide, and fucoxanthin was concentrated successfully in residue. Optimal conditions for concentrating the fucoxanthin from fucoxanthin extract were $40^{\circ}C$ at 9.7 MPa, $45^{\circ}C$ at 11.0 MPa, and $50^{\circ}C$ at 12.4 MPa, respectively. The density of carbon dioxide affected the concentration of fucoxanthin from fucoxanthin extract. In this optimal conditions, the density for concentrating the fucoxanthin was 600 g/L.

• Korean Journal of Food Science and Technology
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• v.22 no.3
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• pp.248-254
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• 1990

Commercial food grade porcine-pancreatic lipase was incorporated into cheese at two different levels of concentration and ripened at $7^{\circ},\;13^{\circ}\;and\;21^{\circ}C$ Gas chromatographic analysis showed that the pancreatic lipase-treated cheese produced significantly higher levels of short-chain free fatty acids than controls. At $21^{\circ}C$ the high level of pancreatic lipase-treated cheese produced medium flavor cheese at 1 wk and close to sharp flavor cheese at 3 wk without causing distinctive defects. The low level of pancreatic lipase-treated cheese developed a number of good quality cheese. They were roughly equivalent to medium and sharp cheeses when ripened at $7^{\circ},\;13^{\circ}\;and\;21^{\circ}C$ for 3 to 15wk. Statistical analyses indicated that there were significant correlations between aged Cheddar flavor and the concentration of c6 as individual short chain free fatty acids (FFA) or C4 and C6 FFA combinations. Pancreatic lipase may be applicable for the accelerated ripening of Cheddar cheese if appropriate conditions are used.

• Preventive Nutrition and Food Science
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• v.9 no.3
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• pp.276-282
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• 2004

Marginal Zn deficiency is prevalent through the world and yet human zinc status has not been properly assessed due to the lack of a reliable diagnostic indicator. One potential possibility for zinc status assessment using Zn-binding protein, metallothionein (MT)-mRNA, has been proposed. The purpose of the present study was aimed to show whether measurement of mononuclear cell (MNC) MT mRNA, using a competitive-reverse transcriptase-polymerase chain reaction (competitive-RT-PCR) assay, could indicate zinc status in human subjects. In this study, MNC MT-mRNA expression was measured using a competitive-RT-PCR to compare before and after 14 days of zinc supplementation (50 mg Zn/das zinc gluconate). RT-PCR oligonucleotide primers which were designed to amplify both a 278 bp segment of the human MT-2A cDNA and a 198 bp mutant competitor cDNA template from MNCs, were prepared. MT-2A mRNA was normalized by reference to the housekeeping gene, $\beta$-actin, mRNA for which was also measured by competitive-RT-PCR. There was considerable inter-individual variation in MT-mRNA concentration and yet, the mean MT-2A mRNA level increased 4.7-fold after Zn supplementation, as compared to before Zn supplementation. This MT-2A mRNA level was shown as the same pattern and, even more sensitive assay, compared to the conventional plasma and red blood cells (RBCs) Zn assessment in which plasma and RBCs zinc levels increased 2.3- and 1.2-fold, respectively (p<0.05). We suggest that MT competitive-RT-PCR can be a useful assessment tool for evaluating human zinc status.