• 한국축산식품학회지
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• 제30권2호
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• pp.223-231
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• 2010

In order to develop a new starter for fermented milk, Lactobacillus paracasei subsp. paracasei BFI46 (BFI46) obtained from new-born infant feces was investigated for physiological characteristics. Good immunomodulating activity was evident compared with commercial lactic acid bacteria starter cultures. The optimum growth temperature of BFI46 was $40^{\circ}C$ with 12 h required to reach pH 4.3. Testing with 13 different antibiotics revealed greatest sensitivity of BFI46 to penicillin- G and chloramphenicol, and heightened resistance to neomycin, kanamycin and polymyxin. BFI46 displayed higher esterase activities compared to 18 other enzymes, was comparatively tolerant to bile juice and able to survive at pH 2 for 3 h, and displayed high resistance against Escherichia coli and Salmonella Typhimurium with a survival rate of 57.14% and 96.36%, respectively. The results indicate that BFI46 could be an excellent starter culture for fermented milk with high level of immunomodulating activity.

• 생명과학회지
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• 제26권12호
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• pp.1438-1445
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• 2016

본 연구는 Lactobacillus paracasei와 Lactobacillus rhamnosus가 요구르트에 오염된 효모의 증식을 억제해서 품질을 향상시키기 위하여 진행하였다. 효모 투입 후 저장기간 동안 효모의 증식 속도는 Lactobacillus paracasei와 Lactobacillus rhamnosus가 포함된 실험구가 대조구에 비해 최소 1일에서 최대 4일까지 지연시켰다. 스웰링 현상은 대조구에 비해 실험구가 효모의 증식 속도를 일정 기간 지연시켜 주는 효과가 있었다. 따라서 요구르트 제조 시 Lactobacillus paracasei와 Lactobacillus rhamnosus를 사용한다면, 저장기간 동안의 품질 안정성이 향상되어 유통기한을 연장할 수 있고, 이로 인해 발효유 제조업체의 생산성과 소비자의 식품 안전성이 향상되는 것으로 사료된다. 또한 Lactobacillus paracasei와 Lactobacillus rhamnosus가 요구르트의 품질 기준인 후산 발효와 관능에 미치는 영향에 대해 조사하였다. 요구르트 제조 후 $10^{\circ}C$에서 저장할 경우 대조구에 비해 실험구의 산도 변화 폭은 미미하여 후산 발효가 거의 일어나지 않았다는 것을 알 수 있었다. 이는 제조일로부터 유통기한 만료일까지 일정하게 관능적 풍미를 유지시켜 줄 수 있다는 것을 의미하며, 이로 인해 소비자에 대한 관능적 품질향상을 꾀할 수 있다. 그리고 Lactobacillus paracasei와 Lactobacillus rhamnosus가 추가된 실험구는 대조구에 비해 조직감이 상대적으로 좋았으며, 풍미나 맛 또한 우수하였다. 즉, 요구르트에 Lactobacillus paracasei와 Lactobacillus rhamnosus의 사용은 효모의 증식 억제를 통해 제품 품질의 안전성 향상, 후산 발효 억제로 인한 품질의 균일성 증대, 조직감 및 풍미 향상으로 인한 관능적 품질 향상에 긍정적인 영향을 끼칠 것으로 판단된다.

• 한국미생물·생명공학회지
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• 제30권2호
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• pp.116-122
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• 2002

김치로부터 분리된 젖산균들의 16S rDNA 부분 염기서열 결정 결과, 6균주 중 2균주는 Leuconostoc mesenteroides로, 나머지 균주는 Lactobacillus속으로 재동정되었다. 이들 김치유래 젖산균들은 유제품 유래 젖산균과 마찬가지로 cell-envelope proteinase (CEP)로 추정되는 세포외 proteinase 활성을 보유하고 있는 것으로 나타났고, 젖산균의 CEP 특이적 primer를 제작하여 PCR을 수행한 결과, Leu. mesenteroides로부터는 예상 크기의 PCR 산물이 증폭되지 않았지만 Lactobacillus속 균주들로부터는 예상되는 1.2 kb 의 DNA 단편이 증폭되었다. Lactobacillus pentosus KFR1821의 genomic DNA로부터 증폭된 PCR 산물의 추정 아미노산서열은 Lactococcus lactis subsp. cremoris의 PrtP와 95％, Labtobacillus paracasei subsp. paracasei이 PrtP와 92％의 높은 상동성을 보였다. 증폭된 PCR 산물을 probe로 하여 Southern hybridization을 수행한 결과, Lb. pentosus KFR1821의 CEP 유전자는 chromosomal DNA에 암호화 되어있는 것으로 확인되었다.

• 대한의생명과학회지
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• 제10권4호
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• pp.403-406
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• 2004

Environmental endocrine disruptors (EDs) are toxic, hormone-like chemicals which can be found in our normal daily life. We have examined if EDs can inhibit the monocellular microorganisms such as lactic acid bacteria or if the growth of lactic acid bacteria could be resistant to the endocrine disruptors. We have used Lactobacillus paracasei subsp. paracasei (KCTC No. 3165) as an experimental strain and bisphenol A, benzophenone and phenylphenol for the comparison purpose. Experiments included the evaluation of turbidity, absorbance and actual cell counts. We found that No.3165 was somewhat resistant to EDs naturally, however, high concentration of EDs could inhibit the growth of No. 3165 completely. Different EDs showed different spectrum of inhibit. This study should contribute to the development of more resistant lactic acid bacteria to EDs and to the development of functional fermented beverage.

• Journal of Applied Biological Chemistry
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• 제56권3호
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• pp.147-156
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• 2013

The objectives of this study were to investigate the effect of Lactobacillus paracasei subsp. tolerans JG22 isolated from pepper leaf jangajji on the mutagenic activity of N-methyl, N'-nitro, N-nitrosoguanidine (MNNG) and 2-nitrofluene (2-NF) and to evaluate the effect of physico-chemical pretreatment on the antimutagenic activity of the strain. The viable cells of JG22 strain displayed a significantly high (p <0.05) antimutagenic activity against both mutagens tested. The antimutagenic effect of JG22 strain seems to be positively correlated with the amounts of the cells in the incubation time. This strain produced the antimutagenic activity of the maximum levels after preincubation for 30 min. The binding of this strain against the mutagenic compounds might be mainly present in the cell wall fraction rather than the cytosol fraction. Pretreatment with proteolytic enzymes and simulated gastric and intestinal juices and at different pH values had no significant effect on two mutagens removal by the viable cells. However, the binding activity of the mutagen by the strain seems to be affected by heating, enzymes including $\alpha$-amylase and lysozyme, divalent ions, and sodium metaperiodate. Thus, carbohydrates consisting of the cell walls may be important elements responsible for the binding of MNNG and 2-NF by this strain. In conclusion, the binding of the mutagens to cells of JG 22 strain may play a vital role in suppressing the process of mutagenesis induced by mutagens.

• 한국미생물·생명공학회지
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• 제29권4호
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• pp.195-200
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• 2001

본 연구는 단위 가축 사료로 이용되는 곡류 등에 존재하는 항연인자인 Phytate 함유 환경하에서의 성장 및 phytate 분해력이 우수한 유산균을 분리하고 발효사료 제조 및 가축 생균제용 균주로의 이용성을 검토하기 위하여 실시하였다. 분리 유산균은 자돈 분변으로부터 얻은 유산균들중 phytate 함유 환경하에서의 성장 및 phytate 분해력이 가장 우수한 균으로 동정결과Lactobacillus paracasei subsp, paracasei로 동정되었다. 분리 규주는 내산성, 내담증섭이 높고, 사료원료를 배지성분으로 하여 순수배양한 결과 대두박 및 밀기울의 phytate-P 분해율이 각각 27.07및 12.18%로 나타났다. 또한 분리 균주를 비육돈 사료에 첨가하여 급여한 결과 중체량 개선효과는 나타나지 않았으나 사료효율 개선효과를 얻을 수 있었다.

• 한국버섯학회지
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• 제11권4호
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• pp.187-193
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• 2013

A galactose fermentation bacterium producing lactose from red seaweed, which was known well to compromise the galactose as main reducing sugar, was isolated from button mushroom bed in Buyeo-Gun, Chungchugnamdo province. The lactic acid bacteria MONGB-2 was identified as Lactobacillus paracasei subsp. tolerans by analysis of 16S rRNA gene sequence. When the production of lactic acid and acetic acid by L. paracasei MONGB-2 was investigated by HPLC analysis with various carbohydrates, the strain MONGB-2 efficiently convert the glucose and galactose to lactic acid with the yield of 18.86 g/L and 18.23 g/L, respectively and the ratio of lactic acid to total organic acids was 1.0 and 0.91 g/g for both substrates. However, in the case of acetic acid fermentation, other carbohydrates besides galactose and red seaweed hydrolysate could not be totally utilized as carbon sources for acetic acid production by the strain. The lactic acid production from glucose and galactose in the fermentation time courses was gradually enhanced upto 60 h fermentation and the maximal concentration reached to be 16-18 g/L from both substrates after 48 h of fermentation. The initial concentration of glucose and galactose were completely consumed within 36 h of fermentation, of which the growth of cell also was maximum level. In addition, the bioconversion of lactic acid from the red seaweed hydrolysate by L. paracasei MONGB-2 appeared to be about 20% levels of the initial substrates concentration and this results were entirely lower than those of galactose and glucose showed about 60% of conversion. The apparent results showed that L. paracasei MONGB-2 could produce the lactic acid with glucose as well as galactose by the homofermentation through EMP pathway.

• 한국축산식품학회지
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• 제36권3호
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• pp.427-434
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• 2016

Benzoic acid is occasionally used as a raw material supplement in food products and is sometimes generated during the fermentation process. In this study, the production of naturally occurring yogurt preservatives was investigated for various starter cultures and incubation temperatures, and considered food regulations. Streptococcus thermophilus, Lactobacillus acidophilus, Lactobacillus delbrueckii subsp. bulgaricus, Lactobacillus rhamnosus, Lactobacillus casei, Lactobacillus paracasei, Lactobacillus reuteri, Lactobacillus plantarum, Bifidobacterium longum, Bifidobacterium lactis, Bifidobacterium bifidum, Bifidobacterium infantis, and Bifidobacterium breve were used as yogurt starter cultures in commercial starters. Among these strains, L. rhamnosus and L. paracasei showed the highest production of benzoic acid. Therefore, the use of L. rhamnosus, L. paracasei, S. thermophilus, and different incubation temperatures were examined to optimize benzoic acid production. Response surface methodology (RSM) based on a central composite design was performed for various incubation temperatures (35-44℃) and starter culture inoculum ratios (0-0.04%) in a commercial range of dairy fermentation processes. The optimum conditions were 0.04% L. rhamnosus, 0.01% L. paracasei, 0.02% S. thermophilus, and 38.12℃, and the predicted and estimated concentrations of benzoic acid were 13.31 and 13.94 mg/kg, respectively. These conditions maximized naturally occurring benzoic acid production during the yogurt fermentation process, and the observed production levels satisfied regulatory guidelines for benzoic acid in dairy products.

• KSBB Journal
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• 제18권1호
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• pp.14-18
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• 2003

본 연구에서는 제지 슬러지를 이용한 SSF 공정에 L..paracasei KLB58을 적용하여 젖산과 더불어 생균제용 균체를 경제적으로 대량 생산하고자 하였다. KLB58의 배양온도와 섬유소 가수분해 효소인 $\beta$-glucosidase의 농도를 조절하여 최적의 생산 조건을 확인해 본 결과, 37$^{\circ}C$ 에서 2 unit/ml의 $\beta$-glucosidase를 첨가하여 배양하였을 때 최대의 젖산과 균체를 생산하였다. 또한 $\beta$-glucosidase를 포함하지 않아도 상대적으로 많은 양의 젖산과 균체를 생산하였으므로, 이에 대한향후 연구가 기대된다.

• Asian-Australasian Journal of Animal Sciences
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• 제21권6호
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• pp.896-902
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• 2008

The objective of this research was to create a new probiotic candy with good flavor and healthy benefits by using the response surface method and a sequential quadratic programming technique. The endpoint was to increase the varieties of dairy products and enhance their market values. In this study, milk was mixed with yogurt cultures (Lactobacillus bulgaricus, Streptococcus thermophilus) and probiotics (L. paracasei, Bifidobacterium longum) and incubated at $37^{\circ}C$ for 20 h. The samples were blended with lyoprotectants (galactose, skim milk powder and sucrose), freeze dried and then mixed with sweeteners (lactose and xylitol) to improve the texture for forming tablets. The processing conditions were optimized in two steps: the first step constructed a surface model using response surface methodology; the second step optimized the model with a sequential quadratic programming procedure. Results indicated that skim milk inoculated with L. delbrueckii subsp. Bulgaricus, S. thermophilus, L. paracasei subsp. paracasei and B. longum and blended with 6.9% of galactose, 7.0% of sucrose and 8.0% of skim milk powder would produce a new probiotic candy with the highest viability of probiotics and good flavor. A relatively higher survival of probiotics can be achieved by placing the probiotic candy product in a glass bottle with deoxidant and desiccant at $4^{\circ}C$. These probiotic counts remained at 106-108 CFU/g after being stored for two months.