• 한국당과학회:학술대회논문집
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• 2006.11a
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• pp.31-31
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• 2006

• Proceedings of the Korean Society for Food Science of Animal Resources Conference
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• 2004.05a
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• pp.318-321
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• 2004

분리동정한 유산균의 cell wall은 murine macrophage를 활성화 시켜 NO와 cytokine을 생성함을 확인하였다. 그 결과 NO 생성량에 있어서는 L. casei SGU 0020에서 가장 높은 분비를 유도하였으며, TNF-a의 분비량은 S. thermophilus SGU 0021의 균주에서 가장 높았다. 그러나 cytokine인 일종인 $IL-1{\beta}$, IL-2, IL-6에 있어서는 L. casei SGU 0020에서 가장 많은 IL의 분비를 유도하였다.

• Preventive Nutrition and Food Science
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• v.2 no.3
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• pp.259-262
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• 1997

The microstructures of soybean milk curds, prepared by different coagulation methods, were observed by the scaning electron microscope. Th curd coagulated by theaddition of bacerial soybean mil clotting enzyme showed little textural changes and gave smoother gel than those prepared either by lactic acid fermentation using Streptococcus thermophilus or by the addition of CaSO$_4$. The curds obtained by lactic acid fermentation and by the addition of inorganic salt exhibited three dimensional network structure which indicated harder gel than that prepared by soybean mil clotting enzyme.

• Culinary science and hospitality research
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• v.12 no.2 s.29
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• pp.195-205
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• 2006

In this study, we investigated the quality characteristics of curd yogurt with different content of Rubus coreanus Miquel juice. Yogurt was fermented with three kinds of lactic acid bacteria(Streptococcus thermophilus, Lactobacillus acidophilus, Lactobacillus casei). The changes of quality characteristics were investigated during fermentation and an acceptance test was performed after fermentation. The pH was decreased on the whole, and titratable acidity was gradually increased during fermentation. The number of viable cells was increased in case of yogurt with 1% to 4% Rubus coreanus Miquel juice, while it was inhibited in the sample with 6% and 7%. There was similar content in composition of protein, lactose, FFA, TS and NFS of curd yogurt after fermentation. Color value of curd yogurt with Rubus coreanus Miquel juice was higher in L(brightness), a(redness) and b(yellowness), compared with the control. Sensory attributes of color, odor, taste, after taste and overall acceptability of the curd yogurt with 3% Rubus coreanus Miquel juice showed highest preference among samples.

• Journal of Food Hygiene and Safety
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• v.14 no.4
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• pp.352-357
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• 1999

Changes in titratable acidity, viable cells and sensory properties of curd yogurt during lactic fermentation in milk added with mugwort extract have been studied. Milk added with 5%, 10％, 15％ or 20% of mugwort extract was fermented with single or mixed culture of Lactobacillus bulgaricus and Streptococcus thermophilus for 24 hours. Addition of mugwort extract markedly stimulated the acid production and propagation of lactic acid bacteria. Among the organism tested, the mixed culture of Lactobacillus bulgaricus and Streptococcus thermophilus produced the highest amount of acid, and Lactobacillus bulgaricus showed the highest number of viable cell counts. Sensory property of curd yogurt added with mugwort extract was evaluated as better than reference sample(milk yogurt). The sample prepared by fermenting milk containing mugwort extract at 5% level with Lactobacillus bulgaricus showed the most favorite characteristics.

• Korean Journal of Food Science and Technology
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• v.36 no.1
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• pp.86-91
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• 2004

Changes in erotic acid (OA) contents of raw milk and during cultivation and storage at refrigerated temperature were determined. OA contents of raw and 10% reconstituted milk held at $121^{\circ}C$ for up to 15 min decreased by 17.6 and 22.4%, and those fermented at 40 and $37^{\circ}C$ for 72 hr with Lactobacillus helveticus 166 and Lactobacillus casei 955 decreased 37.8-43.2 and 41.8-76%, whereas when fermented at $40^{\circ}C$ for 72 hr with Streptococcus thermophilus ST-37, did not decrease significantly compared with fermentation by other lactobacilli. OA content did not change during storage at refrigeration temperature. OA reduction by Lactobacillus sp. was dramatically increased at the initiation of stationary phase during fermentation. OA reduction varied among different lactobacilli. These results show decrease in cultivation time, rapid cooling of yogurt, and proper selection of Lactobacillus sp. prevent OA content reduction.

• Korean Journal of Food Science and Technology
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• v.23 no.6
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• pp.689-694
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• 1991

Jangsu, a Korean ancient non-alcoholic beverage made by lactic acid fermentation of cooked rice, was prepared and the microbial characteristics were investigated. The periodic removal of fermented product and the addition of newly made cooked rice and cold water as new substrate enhanced the growth of lactic acid forming bacteria but supressed the growth of proteolytic bacteria. The important microorganisms in jangsu were Lactobacillus, Lactococcus, Pediococccus and Leuconostoc species. Lactococcus thermophilus, Lactobacillus coryniformis and Leuconostoc mesenteroides were identified. The isolated strains were cultivated and used as starter culture of jangsu. Some useful strains were selected which were able to produce acceptable flavor and sufficient amount of acid lowering the pH to near 4.0.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.12
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• pp.1751-1757
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• 2004

Recombinant heterologous proteins can be produced as insoluble aggregates partially or perfectly inactive in Escherichia coli. One of the strateges to improve the solubility of recombinant proteins is fusion with a partner that is excellent in producing soluble fusion proteins. To improve the production of soluble $\beta$-galactosidase, the gene of Thermus thermophilus KNOUC112 $\beta$-galactosidase (KNOUC112 $\beta$-gal) was fused with thioredoxin gene, and optimization of its expression in E. coli TOP10 was performed. KNOUC112 $\beta$-gal in pET-5b was isolated out, fused with thioredoxin gene in pThioHis C, and transformed to E. coli TOP10. The $\beta$-galactosidase fused with thioredoxin was produced in E. coli TOP10 as dimer and trimer. The productivity of fusion $\beta$ -galactosidase expressed via pThioHis C at 37$^{\circ}C$ was about 5 times higher than that of unfused $\beta$-galactosidase expressed via pET-5b at 37$^{\circ}C$. Inclusion body of $\beta$-galactosidase was formed highly, regardless of the induction by IPTG when KNOUC112 $\beta$ -gal was expressed via pET-5b at 37$^{\circ}C$. Fusion $\beta$ -galactosidase expressed at 37$^{\circ}C$ via pThioHis C without the induction by IPTG was soluble, but the induction by IPTG promoted the formation of inclusion body. Lowering the incubation temperature for the expression of fusion gene under 25$^{\circ}C$ prevented the formation of inclusion body, optimally at 25$^{\circ}C$. 0.07 mM of IPTG was sufficient for the soluble expression of fusion gene at 25$^{\circ}C$. The soluble production of Thermus thermophilus KNOUC112 $\beta$-galactosidase could be increased about 10 times by fusion with thioredoxin, and optimization of incubation temperature and IPTG concentration for induction.

• The Korean Journal of Food And Nutrition
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• v.18 no.3
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• pp.200-206
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• 2005

This study was performed to develop a functional stirred yoghurt prepared from skim milk added with loquat(Eriobotrya japonica Lindley). Skim milk containing $15\%$ loquat extract was fermented by the mixed strains of Streptococcus thermophilus and Lactobacillus acidophilus, and then loquat flesh and oligosaccharide were added to the yoghurt base. Sensory scores of the stirred yoghurt containing $15\%$ loquat flesh and $20\%$ oligosaccharide were higher than other groups in sweet taste, sour taste and overall acceptability. When the levels of oligosaccharide of the stirred yoghurts added with $15\%$ loquat flesh were increased, the L value(brightness) and a value (redness) of the stirred yoghurt decreased, but the b value(yellowness) increased. The hardness, springiness, cohesiveness, gumminess and resilience of the $15\%$ loquat flesh stirred yoghurt added with $20\%$ oligosaccharide were higher than others.

• YAKHAK HOEJI
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• v.49 no.6
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• pp.459-464
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• 2005

The immune reinforcement of the probiotic lactic acid bacteria Lactobacillus acidophilus, Streptococcus thermophilus and Bifidobacterium bifidum was studied in RAW 264.7 cell line treated with diluted solution (dilution to $2^{5}$) of the supernatnats of lactic acid bacteria. RAW 264.7 cell line was used as a macrophage model to assess the effects of lactic acid bacteria on the production of nitric oxide (NO) and cytokine tumor necrosis factor (TNF)-$\alpha$ and cell morphological changes. The production of NO and TNF-$\alpha$ were largely affected by lactic acid bacteria in dose-dependent manner in 24 or 48 hr cultures and cell morphological changes were also largely affected by lactic acid bacteria. Especially Bifidobacterium bifidum differentially stimulated the production of NO and TNF-$\alpha$. NO production was increased by Bifidobacterium bifidum 25 $\mu$l/ml more than LPS (20 ng/ml) control, and TW-$\alpha$ by Bifidobacterium bifidum 6.25 $\mu$l/ml more than LPS (10 ng/ml) control. The in vitro approaches employed here should be useful in further characterization of the effects of lactic acid bacteria on systemic immunity.