• The Korean Journal of Food And Nutrition
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• v.17 no.3
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• pp.286-293
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• 2004

Extract of Eleutherococcus senticosus, Lycium chinensis, Angelica acutiloba and Schizandra chinensis were investigated to determine whether its addition may inflict on growth of lactic acid bacteria, freeze dry and cell viability during the storage. In cultivation with herbal extract, all strains tested did not demonstrate a significant reduction in their cell population, particularly Lactobacillus. acidophilus, L. bulgaricus, L. paracasei. But Schizandra chinensis extract inhibited growth of several strains. Immediately after freeze-drying using the skim milk 10%(w/v), sucrose 5%(w/v) with herbal extract 2.5%(v/v), the percentage viability was about 81.7%, 63.8%, 73.2%, 78.1 % in L. acidophilus, L. bulgaricus, L. paracasei, L. casei respectively. The protective effect of herbal extract to cell damage from freeze-drying was weak in comparison with control. During accelerated storage of freeze-dried lactic acid bacteria, those survival rate decrease rapidly, reaching 8 -18% in one month. But addition of Eleutherococcus senticosus extract in freeze dry of L. acidophilus showed a positive activity in storage.

• Journal of Industrial Technology
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• v.1
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• pp.61-66
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• 1981

In order to use as a starter after drying, optimum growth conditions of Str. thermophilus and L. bulgaricus were investigated. The results were as follows. The growth of Str. thermophilus was reached at stationary phase after 12 hours incubation and L. bulgaricus was after 6 hours. Str. thermophilus was grown well, in the medium containing 10% of skim milk, 2% of sucrose, 0.1% of KCl and 0.015% (v./v.) of soy-sauce. In the case of L. bulgaricus, 10% of skim milk, 2% of glucose, 0.5% of bacto-peptone, 0.1% of $K_2HPO_4$ and 0.02% of pyridoxine was suitable for the maximum growth.

• Food Science and Preservation
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• v.6 no.4
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• pp.442-447
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• 1999

A curd yogurt was prepared by fermenting milk added with skim milk powder and purple sweet potato by culture of 5 types of lactic acid bacteria(Lactobacillus delbruekii sub. sp. lactis, Streptococcus lactis, acidity, number of viable cell, stability of purple sweet potato's pigment and keeping qualify. Among the organisms tested, the acid production and number of viable cell by the culture of L bulgaricus remarkably increased for the first 12 hem which showed 1.04${\times}$10$\^$9/ CFU/mL in number of viable cell and 4.22 In pH where as fermentation by the culture of B. bifidum was slow. After 36 hours of incubation which showed 3.3 ${\times}$ l0$\^$8/ CFU/mL in number of viable cell and 5.1 in pH. In stabilities of purple sweet potato anthocyanin pigment n fermentation, yogurt by B. bifidum was found to be most stable followed by Leuc. lactis, L. delbruekii sub. sp. lactis, L bulgaricus, but yogurt by St. lactis was not stable. When curd yogurt added with Purple sweet Potato was kept at 2∼3$^{\circ}C$ for 14 day, its keeping quality(pH, titratable acidity, number of viable cell) was relative good except product by L. bulgaricus was found to be decreased most of viable cell. After 2 weeks of keeping, pigment of yogurt was decreased by B. bifidum, stable by L. delbruekii sub. sp. lactis.

• Journal of the Korean Society of Food Science and Nutrition
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• v.25 no.1
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• pp.150-156
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• 1996

유산균의 균주개량방법의 일환으로 photoplast fu-sion 기법과 electrofusion법을 이용하여 protease 활성, lipase 활성, 내열성, 내산성 등이 우수한 L. bulgaricus와 bacteriocin을 생산하는 L. acidophilus 간의 융합시켜 얻은 융합주들의 생리학적 성질을 검토하였다. 산 생성능, 내열성, 내산성 protease, lipase 활성 등 L. bulgaricus가 L. acidophilus보다 우수하였다. L. bulgaricus는 lactose와 sorbos를 이용하였으나. mal-tose 와 dorbitol을 이용하지 못하는 반면 , L. acidophilus는 matose를 이용하고 lactose 와 sorbose를 이용하지 못하였다. 융합주 가운데서는 367810번이 모균주의 발효능 특성을 함께 지님으로서 재조합체임을 확인 할 수 있었으며, sorbitol의 경우 모균주에서는 발효능이 전혀 나타나지 않았음에도 불구하고 융합주 4, 7번이 발효능을 나타내어 융합과정에서 새로운 형질을 획득하기도 한다는 사실을 알 수 있었다. Lactase 활성은 모균주 모두 높은 $\beta-galactosidase$ 활성을 보였으나, $phospho-\beta-galactosidase$ 활성은 거의 없었으며 융합주들도 다소 차이는 있었지만 모균주와 유사한 효소활성을 나타내었다. 발효에 있어서 key enzyme으로 작용하는 protease. lipase 등의 효소활성도 모균주의 활성보다 우수한 융합주도 존재하였다.

• Journal of Animal Science and Technology
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• v.45 no.4
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• pp.659-666
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• 2003

Endoglucanase A from Clostridium thermocellum which is resistant to pancreatic proteinase was selected out of numbers cellulases then were expressed in lactobacilli. Recombinant lactobacilli expression vector, pSD1, harboring the endoglucanase gene from C. thermocellum under the control of its own promoter, was constructed. Both L. bulgaricus and L. plantarum were electrotransformed with pSD1. The endoglucanase activities of 0.120 and 0.144 U/ml were found in culture media of L. bulgaricus and L. plantarum containing pSD1, respectively. In vitro survival characteristics of the transformed lactobacilli were tested. Both L. bulgaricus and L. plantarum showed a similar resistance to low pH 3. Moreover, L. plantarum was bile-salt resistant in the presence of 0.3 and 1% oxgall. L. bulgaricus and L. plantarum showed a rather homogenous resistant pattern against the tested antibiotics. Both of the strains were resistant to amikacin, gentamicin, streptomycin, kanamycin, and colistin.

• Korean Journal of Organic Agriculture
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• v.24 no.3
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• pp.497-510
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• 2016

This study was carried out to get basic resources for the industrial use of Lactobacillus bulgaricus SP5. The antibacterial activity of the supernatant obtained from Lactobacillus bulgaricus SP5 was tested against the pathogenic bacteria such as Escherichia coli KCCM 11234, Salmonella enteritidis KCCM 3313, Salmonella enteritidis KCCM 12021, and Salmonella typhimurium KCCM 40253. The supernatant of L. bulgaricus SP5 showed antibacterial activity against tested pathogenic bacteria. The antibacterial activity was examined after adjusting pH and heat treatment of supernatant. Heat treatment of supernatant had antibacterial activity against pathogenic bacteria at all temperature. However, pH changes showed no antibacterial activity. Antibacterial activity of the supernatant was confirmed to be due to organic acids (lactic, acetic, phosphoric, succinic, pyroglutamic, citric, malic, and formic acid).

• Journal of Microbiology and Biotechnology
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• v.14 no.3
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• pp.503-508
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• 2004

The antimicrobial substance produced by Lactobacillus bulgaricus was inactivated by protease. It showed inhibitory activity against Staphylococcus aureus ATCC6538, Streptococcus agalactiae ATCC14364, some Gram-positive and Gram-negative bacteria, and characteristics of a bacteriocin. The optimal temperature and culture time for the production of bacteriocin were $30^{\circ}C$ and 10 h, respectively, in the culture of L. bulgaricus. The bacteriocin production started in the exponential phase and reached a maximum at the early stationary phase. Using Staph. aureus ATCC6538 and Strep. agalactiae ATCC14364, known as common bovine mastitis pathogens, as indicator strains for determination of the bacteriocin activity, the antimicrobial activity of the bacteriocin was found to be stable in acidic and neutral pH's (2- 7) even at lOOT, whereas it was lost at high pH (10- 11) and $100^{\circ}C$. The mode of action for the antimicrobial activity was bacteriocidal, and the molecular weight determined by SDS-PAGE and overlay method was 14 kDa.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2000.05a
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• pp.145-146
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• 2000

The presence of cross-reacting muramidase in Lactobacillus delbrueckii ssp. bulgaricus ULl2 was shown by using monoclonal antibodies raised against an muramidase-2 of Enterococcus hirae ATCC 9790. The separation of protein by sodium dodecyl sulfate-polyacrylamide gel electrophoresis followed by Western immunoblot confirmed the presence of one cross-reacting band in Enterococcus hirae with an estimated molecular mass of 80 kDa, L. bulgaricus cultured cells harvested after 4 and 12 h were submitted to different autolysin releasing procedures and the liberated products were allowed to cross-react with muramidase-2 antibodies in order to estimate the efficiency of each treatment. Although the cultured cells harvested after 4 h yielded only a slight immune-reaction in Western immunoblots against these enzyme monoclonal antibodies, a strong signal was observed for the cell walls obtained from the same experimental conditions and treated with Triton X-100 surfactant. The same phenomenon was also observed by light fluorescence microscopy. Immune-labelling followed by optical and electron microscopy have shown that the muramidase-2 of L. bulgaricus ULl2 was essentially localized in the innermost part of the cell wall.(omitted)

• Food Science of Animal Resources
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• v.30 no.5
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• pp.773-779
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• 2010

The present study was designed to determine the physicochemical properties of yam (Dioscorea) solution fermented by L. bulgaricus, the protective effect of fermented Dioscorea opposita Thunb. on stomach lesions, and the possibility of its application to fermented dairy products. When the concentration of yam increased, the pH increased in raw powder samples but not in extracted powder samples. In 6% raw powder containing the sample, the viable cell counts showed a dramatic increase, whereas those in extracted yam powder significantly decreased in all concentrations during 32 h of fermentation. The viscosity of extracted yam powder showed a lower value than that of raw powder, which was maintained throughout the fermentation. The solution of Dioscorea opposita Thunb. raw powder showed a significantly higher allantoin content compared with the extracted powder (p<0.05). At 2% of added Dioscorea opposita Thunb., 0.65 mg/mL was contained in both samples; however, when 6% of Dioscorea opposita Thunb. was added, the amount of diosgenin increased up to 1.9 mg/mL. When 200 mg of powder/kg body wt. was injected, gastric lesions were apparently reduced compared with those of control rats. With 100 mg/kg body wt. injected into rats, the protective effect was a little lower than that in 200 mg/kg body wt. Based on these data, the present study indicated that yam powder fermented by L. bulgaricus showed a protective effect on gastric lesions in rats; therefore, it may be included as an added ingredient in yogurt manufacture.

• Food Science of Animal Resources
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• v.26 no.2
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• pp.252-256
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• 2006

This study was carried out to investigate characteristics of acid and alcohol fermented milk by mixed starters made by Lactobacillus bulgaricus (KCTC 3635) and Kluyveromyces marxianus (KCTC 17212) for 36 hours when the curds were formed. Final pH and titratable acidity were about 4.5 and 0.68%, respectively. The viable cell counts of lactic acid bacteria and yeast for alcohol fermented milk were increased to $3.2{\times}10^9 CFU/mL$ and $5.3{\times}10^9 CFU/mL$, respectively. The ethanol contents increased to 0.35% during fermentation. Antitumor activities of the fermented milk against tumor cell lines, such as HEp-2, HEC-1B, SW-156 and SK-MES-1 showed to 86.6, 70.3, 60.4 and 57.14%, respectively.