• Korean Journal of Fisheries and Aquatic Sciences
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• v.48 no.5
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• pp.631-638
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• 2015

This study evaluated the quality characteristics of semi-dried small squid Idiosepius paradoxus treated with grapefruit Citrus paradisi seed extract (GSE) during refrigerated storage for 6 months. The moisture content and water activity decreased significantly in both control and GSE-treated groups with increasing storage time, but there was no significant difference between groups. During storage, the degree of water activity reduction was lower in the GSE-treated group than in the control. The pH change was similar in both groups during storage. The thiobarbituric acid reactive substances (TBARS) value of the GSE-treated group was lower than that of the control until 4 months of storage, and was subsequently higher than in the control group. The Hunter color L value did not differ significantly during storage between groups, whereas the a and b values decreased significantly (P<0.05) in both groups with increasing storage time. The hardness value of the semi-dried small squid increased with storage time, but there was no statistical difference between GSE treatment and control. There were more viable cells in the control group than the GSE-treated group after 5 months of storage. According to the sensory evaluation, neither the taste, color, odor, nor texture differed statistically during storage between groups, while overall acceptability was significantly lower in the GSE-treated group than the control after 6 months of storage.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.48 no.5
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• pp.596-603
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• 2015

This study investigated the effects of adding oyster shell powder (OSP) from Crassostrea gigas on the food quality of Chinese cabbage Kimchi (CCK). We monitored the changes in microbial levels, pH, acidity and sensory evaluation during the fermentation of CCK treated with various contents of OSP. The microbial assay showed that adding OSP to CCK inhibited the growth of viable cells, total coliforms, and lactic acid bacteria, with the greatest growth inhibition against lactic acid bacteria over the fermentation period. After fermentation for 18 days, the lactic acid bacterial counts in CCK treated with OSP (0.3%, 0.5% and 1%) were at least 1 log CFU/g lower than those of control CCK. In addition, the pH and acidity of CCK treated with OSP were lower than in control CCK over the fermentation period. The overall sensory evaluation of CCK with 0.3% OSP was better than that of control CCK after fermentation for 24 days. In conclusion, OSP treatment, especially 0.3% OSP, enhances the food quality and extends the self-life of CCK, while minimizing the detrimental effects on its sensory characteristics.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.47 no.5
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• pp.489-494
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• 2014

This study determined the effect of packaging and electron beam irradiation on the quality of dried Undaria pinnatifida. Samples were air or vacuum packaged and irradiated at 7 kGy. The dried Undaria pinnatifida had total viable cells and coliform counts of 5.51 and 4.40 log CFU/g in total, respectively, and counts of 5.56 and 4.19 log CFU/g in surface. These counts were reduced by 2-4 log cycles after irradiation. Irradiation increased the lightness and yellowness of the dried Undaria pinnatifida, but not the redness. In the sensory evaluation, there were no significant differences among samples. Therefore, electron beam irradiation improves the microbial safety and quality of dried Undaria pinnatifida.

• Microbiology and Biotechnology Letters
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• v.17 no.2
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• pp.165-169
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• 1989

To achieve higher ethanol productivity in the fermentation system, a continuous ethanol production has been investigated with the air-supplement in a packed-bed immobilized cell reactor system. Yeast cells were immobilized using sodium alginate gel. The results showed that, when the feed medium was saturated with oxygen through aeration into the medium reservoir, the maximum ethanol productivity of the reactor was enhanced from 35 g/$\ell$-gel-hr to 55 g/$\ell$-gel-hr at the residence time of 10-20 min. and the residence time for the 90% conversion of substrate to ethanol was reduced from 40 min. to 25 min. In case of 18% glucose medium, the maximum productivity was increased from 35 g/$\ell$-gel-hr to 45 g/$\ell$-gel-hr and time required for 90% conversion was from 90 min to 70 min. This behavior of air-supplemented reactor system might be due to the fact that both growth and viable fraction of yeast within the Eel were increased during reactor operation.

• Microbiology and Biotechnology Letters
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• v.48 no.3
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• pp.267-275
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• 2020

Anthocyanins are antioxidant compounds susceptible to environmental factors. Anthocyanin encapsulation into yeast cells is a viable solution to overcome this problem. In this study, the optimal factors for anthocyanin encapsulation were investigated, including anthocyanin concentration, plasmolysis contraction agent, and ethanol concentration, and response surface methodology was evaluated, for the first time. Anthocyanin from Hibiscus sabdariffa L. flowers was encapsulated into Saccharomyces cerevisiae using plasmolysis contraction agent (B: 3%-20% w/v), ethanol concentration (C: 3%-20% v/v), and anthocyanin concentration (A: 0.15-0.45 g/ml). The encapsulation yield and anthocyanin loss rate were determined using a spectrometer (520 nm), and color stability evaluation of the capsules was performed at 80℃ for 30 min. The results of the study showed that these factors have a significant impact on the encapsulation of anthocyanin, in which ethanol agents have the highest encapsulation yield compared to other factors in the study. Statistical analysis shows that the independent variables (A, B, C), their squares (A², B², C²), and the interaction between B and C have a significant effect on the encapsulation yield. The optimized factors were anthocyanin, 0.25 g/ml; NaCl, 9.5% (w/v); and ethanol, 11% (v/v) with an encapsulation yield of 36.56% ± 0.55% and anthocyanin loss rate of 15.15% ± 0.98%; This is consistent with the expected encapsulation yield of 35.46% and loss rate of 13.2%.

• Archives of Pharmacal Research
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• v.28 no.6
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• pp.660-666
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• 2005

The intestinal microbiota are important to the host with regard to resistance they impart against bacterial infections and their involvement in mediating metabolic functions. Lactic acid producing bacteria such as Lactobacillus play an important physiological role in these matters. The aim of the present study was to isolate Lactobacillus sp. that inhibits enteric pathogens. Initially, 17 isolates from healthy Koreans were collected on Lactobacillus selective medium. Resistance of the isolates to antibiotics including rifampicin, streptomycin, clindamycin and vancomycin was measured. One of the isolate was identified as Lactobacillus ruminus on the basis of bacterial cell morphology, cultural characteristic and biochemical characteristics, 16S rRNA sequence analysis and PCR-RAPD. Antimicrobial activity of the bacterium against Vancomycin Intermediate Resistant Staphylococcus aureus (VISA) and Vancomycin-Resistant Enterococci (VRE) was measured. About $10^4$ cells of VISA or VRE were mixed with 1, 5, and 9 mL of L. ruminus SPM 0211 and the final volume was adjusted to 10 mL with brain heart infusion (BHI) broth. The cell suspension was incubated for 3, 6, 9, and 24 h, serially diluted and then plated on BHI agar plates. As numbers of L. ruminus SPM 0211 were increased, viable cell count of VISA and VRE decreased. The strongest antimicrobial activity of SPM 0211 was observed after 9 h incubation in any mixture, almost completely inhibiting the growth of these two bacteria. The results suggest that the freshly isolated L. ruminus SPM 0211 may be used as a pro-biotic microbe that prevents the colonization of enteric pathogens and can thereby promote good gastrointestinal health.

• Journal of the East Asian Society of Dietary Life
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• v.22 no.3
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• pp.408-413
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• 2012

This study aimed to evaluate the physiochemical properties and fermentation qualities of kimchi supplemented with yacon (Smallanthus sonchifolius) during fermentation. Kimchi supplemented with 0%, 0.1%, 0.5%, 1%, and 5% yacon were investigated. As fermentation proceeded, pH decreased from 5.5~5.7 on the first day to 4.6~4.8 on day 21, whilst total titratable acidity (TTA), lactate levels, and number of microbes increased. The kimchi with 5% yacon showed a higher production of lactate concentration at 7 days fermentation than other groups, which is consistent with the observed high numbers of viable Leuconostoc sp. cells at 7 days fermentation. These observations demonstrate that 5% yacon stimulates the growth of kimchi microbes, particularly of Leuconostoc sp..

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.5
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• pp.633-639
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• 2008

The quality characteristics of white pan bread prepared with chungkukjang powder were investigated. Breads were prepared with the addition of 0, 0.5, 1.0, and 1.5% of chungkukjang powder to the basic formulation. The bread volume slightly decreased from 0% to 1.5%. pH was nearly unchanged. As the added amount of chungkukjang powder increased, lightness (L-values) decreased while redness (a-values) and yellowness (b-values) increased. During storage, total viable cells of the control bread increased. In preference characteristics, the highest sensory scores for color, air cell, smell and softness were obtained when chungkukjang powder content was 0.5%. The intensity characteristics related to color and smell were the strongest with increasing chungkukjang powder. These results showed that the white pan bread with 0.5% chungkukjang powder was acceptable.

• Culinary science and hospitality research
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• v.18 no.3
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• pp.239-251
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• 2012

This study was conducted to examine the physicochemical and sensory characteristics of teriyaki sauce added with jujube concentrate. Brix of teriyaki sauce groups added with jujube concentrate were higher than the control. Increased amount of jujube concentrate in the teriyaki sauce tended to increase the viscosity, lightness(L), redness(a) and yellowness(b) values while it tended to decrease pH, the salinity and free amino acid contents. In sensory evaluation, teriyaki sauce added with 20% jujube concentrate had excellent score in sensory preference. Total viable cells of teriyaki sauce by the storage period, not found in control and teriyaki sauce added with jujube. Based on the results, 20% should be recommended as the optimum level of jujube concentrate to be added for the preparation of teriyaki sauce.

• Journal of Plant Biotechnology
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• v.45 no.3
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• pp.257-265
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• 2018

Sweetener is one of the additives that makes you feel sweet. Artificial sweeteners and sugar are typical examples, and sweetness proteins with sweetness characteristics have been widely studied. These studies elucidated the transformation lettuce cells with Agrobacterium method for stable production of natural sweet proteins, brazzein, thaumatin, and miraculin. In this paper, we report use of a plant expression system for production of sweet proteins. A synthetic gene encoding sweet proteins was placed under the control of constitutive promoters and transferred to lettuce. High and genetically stable expression of sweetener was confirmed in leaves by RT-PCR and Western blot analysis. Sweet proteins expressed in transgenic lettuce had sweetness-inducing activity. Results demonstrate recombinant sweet proteins correctly processed in transgenic lettuce plants, and that this production system could be a viable alternative to production from the native plant.