• 한국축산식품학회지
• /
• 제38권6호
• /
• pp.1144-1154
• /
• 2018

Both the calcium and collagen in bone powder are hard to be absorbed by the body. Although enzymatic hydrolysis by protease increased the bio-availability of bone powder, it was a meaningful try to further increase $Ca^{2+}$ release, oligopeptide formation and antioxidant activity of the sheep bone hydrolysate (SBH) by lactic acid bacteria (LAB) fermentation. Lactobacillus helveticus was selected as the starter for its highest protease-producing ability among 5 tested LAB strains. The content of liberated $Ca^{2+}$ was measured as the responsive value in the response surface methodology (RSM) for optimizing the fermenting parameters. When SBH (adjusted to pH 6.1) supplemented with 1.0% glucose was inoculated 3.0% L. helveticus and incubated for 29.4 h at $36^{\circ}C$, $Ca^{2+}$ content in the fermented SBH significantly increased (p<0.01), and so did the degree of hydrolysis and the obtaining rate of oligopeptide. The viable counts of L. helveticus reached to $1.1{\times}10^{10}CFU/mL$. Results of Pearson correlation analysis demonstrated that LAB viable counts, $Ca^{2+}$ levels, obtaining rates of oligopeptide and the yield of polypeptide were positively correlated with each other (p<0.01). The abilities of SBH to scavenge the free radicals of DPPH, OH and ABTS were also markedly enhanced after fermentation. In conclusion, L. helveticus fermentation can further boost the release of free $Ca^{2+}$ and oligopeptide, enhance the antioxidant ability of SBH. The L. helveticus fermented SBH can be developed as a novel functional dietary supplement product.

• 한국식품영양과학회지
• /
• 제41권5호
• /
• pp.721-726
• /
• 2012

본 연구는 김치 내에서 균들의 생육을 조절하고 김치의 저장성과 안전성을 향상시키고자 김치로부터 항균활성이 우수한 박테리오신 생산 유산균을 동정 및 박테리오신의 특성을 확인하고자 하였다. 그 결과 항균활성이 뛰어난 $Lb.$ $sakei$ B16을 선발하였고 이 균주에서 생산되는 박테리오신은 pH와 열에 안정하고 일반적으로 박테리오신이 그람 양성균을 저해하는 것에 비해 본 연구에서 분리한 박테리오신은 그람 음성 유해균을 저해하여 넓은 저해 범위를 갖는 장점이 있다. 반면, trypsin, proteinase K, ${\alpha}$-chymotrypsin을 처리하였을 때 항균 활성이 저하되는 것을 확인하였다. 따라서 본 연구에서 분리한 박테리오신은 다양한 환경 변화에서 안정하고 체내에 섭취되었을 때 단백질 가수분해 효소에 의해 분해됨으로써 인체에 영향을 주지 않을 것으로 생각된다. 또한 sakacin P cluster 염기서열 정보를 이용하여 $Lb.$ $sakei$ B16에서 박테리오신 유전자의 존재를 확인하였다. 본 연구를 통해 유산균이 생산하는 박테리오신을 이용하여 김치 제조 산업에서 스타터로 개발하여 김치 내에서 미생물의 생육을 조절하고 김치의 저장성과 품질을 향상시킬 수 있을 것이라 기대된다.

• 한국축산식품학회지
• /
• 제38권1호
• /
• pp.110-122
• /
• 2018

Akcakatik cheese (yogurt cheese) is produced by drying strained yogurt with or without adding cloves or black cumin. The main objective of this study was to detect the properties of both fresh and ripened Akcakatik cheeses and to compare them. For this purpose the biogenic amine content, volatile flavor compounds, protein degradation level, chemical properties and some microbiological properties of 15 Akcakatik cheese samples were investigated. Titratable acidity, total dry matter, NaCl, total nitrogen, water soluble nitrogen, ripened index, histamine, diacetyl and acetaldehyde levels were found to be higher in ripened cheese samples than in fresh cheese samples. On the other hand, the clove and black cumin ratios were found to be higher in the fresh cheese samples. Sodium dodecyl sulphate polyacrylamide gel electropherograms of cheese samples showed that protein degradation was higher in ripened cheese samples than in fresh samples, as expected. The dominant Lactic acid bacteria (LAB) flora of Akcakatik cheese samples were found to be Streptococcus salivarius subsp. thermophilus and Lactobacillus delbrueckii subsp. bulgaricus.

• Journal of Microbiology and Biotechnology
• /
• 제14권4호
• /
• pp.852-858
• /
• 2004

The morbidity and mortality of colon cancer are increasing, because of the westernization of food habit. Probiotics such as lactic acid bacteria (LAB) have been known to play an important role in retarding colon carcinogenesis by possibly influencing metabolic, immunologic, and protective functions in the colon. In this study, we evaluated the effect of B. polyfermenticus SCD on N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) induced DNA damage in CHO-K, cells and human lymphocytes, and on proliferation of human colon cancer cell. Using the Comet assay to detect DNA damage, we found that B. polyfermenticus SCD protected cells from the DNA damage induced by MNNG in $CHO-K_1$ cells and in human lymphocytes. B. polyfermenticus SCD was also found to inhibit the growth of colon cancer cells in a dose-dependent manner, detected by the MTT assay. These results indicate that B. polyfermenticus SCD has the potential to inhibit not only DNA damage induced by a carcinogen, but also the proliferation of colon cancer cells.

• 미생물학회지
• /
• 제53권2호
• /
• pp.134-136
• /
• 2017

이유자돈용 생균제 개발을 위해, 본 연구자들은 유산균의 일종인 Lactobacillus salivairus KLW001 균주를 대한민국 양돈가에서 사육 중인 이유자돈으로부터 분리하였다. 이 균주는 K88 antigen-positive Escherichia coli, Salmonella enterica serovar Typhimurium에 대한 항균 활성이 타 균주보다 우수하여, 우리는 이 균주의 유전체를 분석하였다. 유전체 초안 속의 166개 Contig (${\geq}500bp$)들에서, G+C content (%)가 33.0%였고, 2,326,706 bp 크기의 염기서열을 확보할 수 있었다. 유전체 초안으로부터 항생제 저항 유전자 4개, Phage 관련 유전자 36개, Bile 대사 유전자 3개, CRISPR Spacer 27개를 확인하였다.

• 한국축산식품학회지
• /
• 제41권2호
• /
• pp.196-213
• /
• 2021

The objective of this study was to determine the effects of yeast cultures (Candida zeylanoides and Debaryomyces hansenii) isolated from traditionally dry fermented Turkish sucuks, on some physicochemical and microbiological properties of the product. Eight different batches of the sucuks were produced by the inoculation of yeast and lactic acid bacteria (LAB) cultures (Lactobacillus curvatus, Lactobacillus plantarum and Lactobacillus sakei) in different combinations. The sucuks were ripened for 12 days and analyzed at 1st, 6th, and 12th days of ripening. Percent moisture content, pH, water activity (aw) and residual nitrite values of the sucuk inoculated with the yeast cultures were higher at the end of the ripening. The use of yeast cultures decreased hardness, gumminess, and chewiness values of the sucuk while increased adhesiveness values. Major volatile groups were aldehydes, terpenes, and sulphur compounds in the sucuk samples. The most noticeable results were for sensory properties of the sucuk that were positively improved by the yeast cultures.

• 미생물학회지
• /
• 제46권4호
• /
• pp.375-382
• /
• 2010

갓김치로부터 분리된 유산균 5종(Lactobacillus acidophilus GK20, Lactobacillus brevis GK55, Lactobacillus paracasei GK74, Lactobacillus plantarum GK81, 및 Leuconostoc mesenteroides GK104)의 활성산소종에 대한 저항성 및 항산화 활성을 조사하였다. Hydrogen peroxide (0.5 mM)와 반응 5시간후 L. acidophilus GK20, L. brevis GK55, L. paracasei GK74 및 L. plantarum GK81들은 50% 이상의 생존율을 보였으며, superoxide anions에 의한 저해율은 L. acidophilus GK20와 L. paracasei GK74가 가장 낮았고, hydroxyl radical과의 반응에서는 L. paracasei GK74와 L. plantarum GK81이 가장 안정하였다. 한편, L. plantarum GK81는 실험 균주 중 가장 높은 DPPH 소거능($70.8{\pm}10.1%$)을 나타내었는데, 세포(IC)보다는 세포추출물(ICFE)의 활성이 더 높았다. 또한 L. plantarum GK81의 ICFE는 다른 균주들에 비해 높은 superoxide radical 소거능을 보였고, 이 균주의 IC와 ICFE에 의한 환원력은 BHA와 vitamin C보다 유의적으로 더 높게 나타났으며, L.paracasei GK74 IC의 환원력도 vitamin C와 비슷한 수준으로 나타났다. L. brevis GK55, L. paracasei GK74 및 L.mesenteroides GK104 IC의 $Fe^{2+}$-chelating 활성은 30% 이상이었고, L. plantarum GK81의 ICFE는 45% 이상의 활성을 나타내었다. 따라서 실험 균주 중 L. plantarum GK81은 다른 균들에 비해 ROS에 대해 비교적 안정하고, 항산화 활성도 가장 높은 것으로 확인되었다.

• Journal of Microbiology and Biotechnology
• /
• 제24권12호
• /
• pp.1629-1635
• /
• 2014

It is known that lactic acid bacteria (LAB) have many beneficial health effects, including anti-oxidative activity and immune regulation. In this study, the immune regulatory effects of Lactobacillus sakei and Lactobacillus plantarum, which are found in different types of kimchi, were evaluated. L. sakei and its lipoteichoic acid (LTA) have greater immune stimulating potential in IL-12, IFN-${\gamma}$, and TNF-${\alpha}$ production as compared with L. plantarum in an in vitro condition. On the other hand, L. plantarum is assumed to repress the Th1 immune response in murine experiments. After being injected with LPS, L. plantarum-fed mice maintained a healthier state, and the level of TNF-${\alpha}$ in their blood was lower than in other bacterial strainfed mice and in the LPS-only control mice. Additionally, IL-12 production was significantly decreased and the production of IL-4 was greatly increased in the splenocytes from L. plantarum-fed mice. Further experiments revealed that the pre-injection of purified LTA from L. plantarum (pLTA), L. sakei (sLTA), and S. aureus (aLTA) decreased TNF-${\alpha}$ and IL-4 production in LPS-injected mice. Mouse IL-12, however, was significantly increased by aLTA pre-injection. In conclusion, the L. sakei and L. plantarum strains have immune regulation effects, but the effects differ in cytokine production and the regulatory effects of the Th1/Th2 immune response.

• 한국축산식품학회지
• /
• 제35권3호
• /
• pp.339-349
• /
• 2015

The objective of this study was to identify lactic acid bacteria (LAB) isolated from kimchi and to evaluate its characteristics and functional properties for application in fermented dairy products as a probiotic or commercial starter culture. Eight stains isolated from kimchi were selected through an investigation of phenotypic characteristics. Two strains (DK211 and DK303) were identified as Lactobacillus plantarum, another two (DK207 and DK215) as Lactobacillus paracasei, and one (DK301) as Lactobacillus sakei. The remaining three strains were identified as species of Weissella. All selected Lactobacillus strains had acid and bile tolerance, even though there was wide variation in the ability of each strain. DK303 showed a remarkably higher proteolytic activity. There were no significant differences in β-galactosidase activity among the tested strains, except that DK301 showed no activity. Auto-aggregation varied between 82.1 and 90.0%, and hydrophobicity values ranged from 0.5 to 51.6%.The strongest auto-aggregation and hydrophobicity were observed in DK211. All selected strains showed better 1,1-diphenyl-2-picrylhydrzyl (DPPH) scavenging activity than commercial strains. DK211, DK215, DK301, and DK303 had effective inhibitory activity against all pathogens tested except E. coli. When selected strains were used for yogurt preparation as a single starter culture, the time required to reach target titratable acidity (0.9) was 11-12 h. The yogurt fermented with DK211 had favorable panelists ratings for most sensory attributes, which were comparable with yogurt fermented with a commercial strain. The results suggest that strains isolated from kimchi could be potential probiotic and starter cultures for use in yogurt manufacturing.

• 한국축산식품학회지
• /
• 제29권5호
• /
• pp.640-646
• /
• 2009

발효유제품, 김치, 및 신생아 분변 등에서 유산균을 분리하여 isoflavone 전환 능력을 평가하였다. 유산균 중 높은 수준의 $\beta$-glucosidase 활성을 보인 균주는 Enterococcus sp. 77, L. paracasei, Lactobacillus sp. 712, L. brevis ATCC 8287, Lactococcus sp. KU107, L. acidophilus KCNU, L. plantarum L155 등으로 나타났다. 이들 유산균에 대하여 유당 발효성을 평가하여 가장 우수한 유산균을 선발하여 API, 16S rDNA를 분석한 결과 Lactobacillus plantarum으로 동정되었으며 이 활성 유산균을 Lactobacillus plantarum YS712로 명명하였다. Lactobacillus plantarum YS712는 pH 2.5에서도 약 50% 이상의 강한 생존율을 보였으며 DPPH 라디칼 소거능도 95.8%로, 선발된 유산균 중 가장 높은 라디칼 소거능을 나타내었다. 이로써 Lactobacillus plantarum YS712는 발효식품 및 유제품에 다양하게 이용할 가치가 있다고 판단된다.