• Food Science of Animal Resources
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• v.44 no.4
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• pp.951-965
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• 2024

Lactiplantibacillus plantarum is a valuable potential probiotic species with various proven health-beneficial effects. L. plantarum LM1001 strain was selected among ten strains of L. plantarum based on proteolytic activity on whey proteins. L. plantarum LM1001 produced higher concentrations of total free amino acids and branched-chain amino acids (Ile, Leu, and Val) than other L. plantarum strains. Treatment of C2C12 myotubes with whey protein culture supernatant (1%, 2% and 3%, v/v) using L. plantarum LM1001 significantly increased the expression of myogenic regulatory factors, such as Myf-5, MyoD, and myogenin, reflecting the promotion of myotubes formation (p<0.05). L. plantarum LM1001 displayed β-galactosidase activity but did not produce harmful β-glucuronidase. Thus, the intake of whey protein together with L. plantarum LM1001 has the potential to aid protein digestion and utilization.

• Food Science and Biotechnology
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• v.17 no.5
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• pp.925-930
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• 2008

Norovirus has become the most common cause of human gastroenteritis in developed countries. Detection procedures of foodborne viruses from foods require several steps. The concentration step using polyethylene glycol (PEG) is time-consuming and the detection efficiency of reverse transcription-polymerase chain reaction (RT-PCR) is affected by inhibitors from food components. In this study, a rapid detection method based on buoyant density centrifugation was developed to replace the time-consuming chloroform-polyethylene glycol-Tris Tween method. Feline calicivirus that belongs to the family Caliciviridae was used as a surrogate model for norovirus. After artificial inoculation of feline calcivirus (FCV) to oyster and lettuce, 830 ${\mu}L$ of homogenized sample suspension was layered on the top of 670 ${\mu}L$ 20% percoll and centrifuged. Then RNA extraction step was proceeded with the supernatant. By varying several physical conditions, the detection limits were lowered to $2.4{\times}10^2$ PFU per 1 g in oyster and $2.4{\times}10^0$ PFU per 1 g in lettuce. The protocol obtained in this study could be used to develop new detection method for norovirus in foods.

• Korean Journal of Food Science and Technology
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• v.41 no.3
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• pp.350-353
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• 2009

Peanut (Arachis hypogaea) often causes severe allergic reactions in sensitive people. Agglutinin is known to be one of the allergenic proteins in peanut. A polymerase chain reaction (PCR) method was developed to detect peanut ingredients in food using a primer pair corresponding to the agglutinin gene. This primer pair enabled PCR amplification of specific regions of agglutinin DNA from peanut, but not from 11 other nuts, beans, and cereals (pistachio, almond, sunflower seed, pine nut, walnut, soybean, black bean, kidney bean, azuki bean, rice, and black rice). The proposed PCR method successfully identified all of the 6 processed foods containing peanut whereas 13 other processed foods, which don't declare peanuts as an ingredient, were all negative. The detection limit of this method for purified peanut DNA was 100 pg/reaction. The sensitivity of this method was sufficient to detect peanut DNA in soybean DNA mixture which had been spiked with 0.1% peanut DNA.

• Journal of the Korean association of regional geographers
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• v.19 no.4
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• pp.567-579
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• 2013

The purpose of this paper is illuminating positively the perception and compliance rate of local food principles in Korea. The results are as follows. First, in terms of the perception rate, social trust and local production/consumption are the most important components rather than eco-friendliness. This means the importance of both spatial and social aspects of local food concept. Second, in terms of the compliance rate, social trust and shortened food chain are well complied, rather than eco-friendliness and shortened food miles. Third, in terms of the difference between perception and compliance rate, the social aspects such as eco-friendliness, social trust, and shortened food chain has shown relatively smaller difference than the spatial aspects such as shortened food miles and local production/consumption.

• Journal of Microbiology and Biotechnology
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• v.26 no.8
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• pp.1398-1403
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• 2016

The simultaneous detection and accurate identification of hepatitis A virus (HAV) is critical in food safety and epidemiological studies to prevent the spread of HAV outbreaks. Towards this goal, a one-step duplex reverse-transcription (RT)-PCR method was developed targeting the VP1/P2B and VP3/VP1 regions of the HAV genome for the qualitative detection of HAV. An HAV RT-qPCR standard curve was produced for the quantification of HAV RNA. The detection limit of the duplex RT-PCR method was 2.8 × 10¹ copies of HAV. The PCR products enabled HAV genotyping analysis through DNA sequencing, which can be applied for epidemiological investigations. The ability of this duplex RT-PCR method to detect HAV was evaluated with HAV-spiked samples of fresh lettuce, frozen strawberries, and oysters. The limit of detection of the one-step duplex RT-PCR for each food model was 9.4 × 10² copies/20 g fresh lettuce, 9.7 × 10³ copies/20 g frozen strawberries, and 4.1 × 10³ copies/1.5 g oysters. Use of a one-step duplex RT-PCR method has advantages such as shorter time, decreased cost, and decreased labor owing to the single amplification reaction instead of four amplifications necessary for nested RT-PCR.

• Food Science and Biotechnology
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• v.17 no.4
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• pp.761-765
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• 2008

Bacillus cereus causes two different types of food poisoning syndromes: diarrhea and emesis. The diarrheal syndrome is attributed to various enterotoxins, including nonhemolytic enterotoxin, hemolytic enterotoxin, and enterotoxin-T, whereas the emetic syndrome is caused by the dodecadepsipeptide toxin cereulide. A multiplex polymerase chain reaction (PCR) assay was developed to rapidly detect and identify B. cereus strains. Three primer pairs specific to regions within genes encoding nonhemolytic enterotoxin (nheA), molecular chaperonin (groEL), and cereulide synthetase (ces) were used to identify and differentiate between the enterotoxin-producing and emetic toxin-producing B. cereus strains. The cereulide-producing emetic B. cereus showed 3 PCR products of 325, 405, and 685 bp for the groEL, ces, and nheA genes, respectively, whereas the enterotoxin-producing B. cereus showed 2 PCR products without a ces gene specific DNA fragment. Specific amplifications and differentiations by multiplex PCR assay were obtained using 62 B. cereus strains and 13 strains' of other bacterial species. The detection limit of this assay for enterotoxin-producing strain and emetic toxin-producing strain from pure cultures were $2.4{\times}10^1$ and $6.0{\times}10^2\;CFU/tube$, respectively. These results suggest that our multiplex PCR method may be useful for the rapid detection and differentiation of B. cereus strains in foods.

• Journal of Food Hygiene and Safety
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• v.33 no.2
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• pp.146-150
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• 2018

Red pepper is one of the most important spices popularly utilized in Korea. Because of the differences in tariff rates between red pepper powder and seasoned red-pepper sauce, seasoned red-pepper sauce is often therefore imported by consumers, then dried, ground, and added to red pepper powder for cost effective purposed to use the product the most effectively. In this study, we combined species-specific polymerase chain reaction (PCR) assays (for red pepper, garlic, onion, spring onion, and ginger) with whole-genome amplification (WGA). Thirty-nine red pepper powders were well in accordance with their labels. However, six red pepper powder and five seasoned red-pepper sauce products failed to meet their compliance requirements. As a consequence, our monitoring results revealed that the overall mislabeling rate detected in this study was identified at 22%. Thus, our findings showed that the species-specific PCR in conjunction with WGA was an ideal method to identify raw materials that are used in the manufacturing of red pepper powder and seasoned red-pepper sauce.

• Korean Journal of Food Science and Technology
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• v.21 no.5
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• pp.624-632
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• 1989

Lipids of Liza carinata roe were extracted and separated into detailed lipid classes by column chromatography. About 57-62% of the total lipids consisted of wax esters in which saturated and unsaturated fatty alcohols combined with fatty acids with up to six double bonds. Between the even-numbered wax ester peaks in gas-liquid chromatography, ones with odd chain lengths such as C31, C33 and C35 were eluted in appreciable amounts. Isomers composed of different fatty acids and alcohols at a given chain length were not resolved on 1.5% OV-17 column. The principal component of wax esters in sample A were C32, C34 and C30 (45.0%, 19.2%, and 12.2%), followed by C36 and C38 length (9.5% and 4.7%), while those in sample B were mainly occupied by C34, C32 and C36 length (36.3%, 31.4% and 14.5%) with minor components C30 and C38 length (5.2%, and 3.4%). The wax esters were not a random combination of constituent fatty acids and alcohols. With increase in boiling temperature the wax esters increased slightly in viscosity over the unboiled, showing a tendency toward randomness, and finally were completely randomized at $360^{\circ}C$ for 40 minutes. The enzymes involved in wax ester biosynthesis seemed to have high selectivity for chain length of fatty acids and alcohols.

• Korean Journal of Food Science and Technology
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• v.30 no.4
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• pp.883-887
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• 1998

Protease activities were measured in vegetables used as cooking material or a side dish. Proteases of green pepper (Kwari and Chungyang), perilla leaves, soybean sprout and mungbean sprout were showed high activities. Especially, protease in soybean sprout was the highest activity among them. After dialysis, remaining activities in mungbean sprout, green pepper (Kwari and Chungyang) and perilla leaves were 12, 23, 45% and 37%. In the results of thawing after freezing the proteases, remaining activities in sprout of mungbean and soybean were 100% and 65%. Protease in soybean sprout was showed higher activity and stability than others. Proteolytic effects of soybean sprout on myofibrillar and sarcoplasmic protein were showed higher than stroma protein. In SDS-PAGE, myosin heavy chain, actin and tropomyosin were hydrolyzed with increasing time. Protease activity was rapidly increased with increasing meat concentration in a early proteolysis reaction, but was slightly increased in later.

• Journal of Service Research and Studies
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• v.13 no.2
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• pp.1-23
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• 2023

In this study, we try to discover some success factors, for the entire value chain of the O2O food delivery industry in China, from ordering to delivery. We study the influence of three aspects of the value chain, namely, (1) the mobile platform, (2) the restaurant and food and (3) the delivery service, on the perceived value and repurchase intention of customers. Using structural equation modeling, we develop a structural research model with seven sets of hypotheses relating various independent variable constructs (platform, restaurant, and delivery) and dependent constructs (perceived value and repurchase intention). We find that usefulness of mobile app, the food condition and the availability of offline restaurants were significant antecedents for perceived value and repurchase intention. In addition, fair pricing was a significant antecedent for repurchase intention.