• 미생물학회지
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• 제49권3호
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• pp.262-269
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• 2013

본 연구진은 청국장에서 수종의 미생물을 분리하였으며, 이중 소화 효소능이 뛰어난 균주를 선별하였으며, 유전학적 분석결과를 통해 본 균주가 Bacillus 속 균주임을 확인하고 Bacillus subtilis BC-P1이라 명명하였다. Bacillus subtilis BC-P1을 starter로 사용하여 청국장을 제조하였으며, protease, xylanase, chitinase activity, 혈전 분해능, 영양성분 분석 및 아미노산 분석을 통하여 B. subtilis BC-P1를 starter로 활용한 청국장 제품의 개선 가능성을 타진하였다. Bacillus subtilis BC-P1를 starter로 제조한 청국장은 기존 제품에 비해 우수한 소화효소 생성능을 보였으며, 특히 혈전분해효소 생성능이 우수함을 확인하였고, 대조군에 비해 증가된 환원당 및 총 아미노산 함량을 확인 할 수 있었다. 따라서 본 균주를 starter로 하여 청국장을 제조할 경우 기능성분, 생리활성의 증가, 품질 향상을 기대할 수 있을 것으로 판단되며, 향후 대규모 생산시 균주, 제조 조건에 관한 연구가 필요할 것으로 사료된다.

• 한국유기농업학회지
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• 제22권3호
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• pp.491-502
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• 2014

본 연구는 천연물질에서 유래한 반추위 메탄저감용 친환경 첨가제 개발을 위해 각기 다른 종균을 이용하여 발효한 세신 추출물의 항균활성, 항산화활성 및 in vitro 반추위 발효시험을 체계적으로 실시하였다. 접종된 균주들의 성장효율을 알아보기 위해 실시한 생균수측정 결과 L. curvatus NJ40 균주에서 유의적으로 높은 균주성장을 나타냈다(p<0.05). 항균활성측정 결과는 대조구 대비 L. curvatus NJ40 및 L. plantarum NJ45 균주와 발효된 세신 추출물이 병원균에 대한 항균효과를 나타내는 것으로 조사되었다. In vitro 반추위 발효실험에 세신 및 발효 세신 추출물을 적용한 결과, 휘발성 지방산 생성량 대비 반추위 메탄 저감효과가 나타났다. 특히 반추위 미생물 활력 및 사료이용 효율을 대표할 수 있는 휘발성 지방산 생성효율에 대한 부정적 효과 없이, 오히려 휘발성지방산 생성효율을 향상시키면서 반추위 메탄 저감효과를 가져올 수 있는 것으로 나타났다.

• 한국미생물·생명공학회지
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• 제47권3호
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• pp.343-349
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• 2019

Gul jeotgals (GJs) were prepared using solar salt aged for 3 years. One sample was fermented using starters, such as Bacillus subtilis JS2 and Tetragenococcus halophilus BS2-36 (each $10^6CFU/g$), and another sample was fermented without starters for 49 days at $10^{\circ}C$. Initial counts of bacilli and lactic acid bacteria (LAB) in non-starter GJ were found to be $3.20{\times}10^2$ and $7.67{\times}10^1CFU/g$ on day 0, and increased to $1.37{\times}10^3$ and $1.64{\times}10^6CFU/g$ on day 49. Those of starter GJ were found to be $2.10{\times}10^5$ and $3.30{\times}10^7CFU/g$ on day 49, indicating the growth of starters. The pH values of GJ were $5.93{\pm}0.01$ (non-starter) and $5.92{\pm}0.01$ (starter) on day 0 and decreased to $5.78{\pm}0.01$ (non-starter) and $5.75{\pm}0.01$ (starter) on day 49. Amino-type nitrogen (ANN) production increased continuously during fermentation, and $407.19{\pm}15.85$ (non-starter) and $398.04{\pm}13.73$ (starter) mg% on day 49. Clone libraries of 16S rRNA genes were constructed from total DNA extracted from non-starter GJ on days 7, 21, and 42. Nucleotide sequences of Escherichia coli transformants harboring recombinant pGEM-T easy plasmid containing 16S rRNA gene inserts from different bacterial species were analyzed using BLAST. Uncultured bacterium was the most dominant group and Gram - bacteria such as Acidovorax sp., Afipia sp., and Variovorax sp. were the second dominant group. Bacillus amyloliquefaciens (day 7), Bacillus velezensis (day 21 and 42), and Bacillus subtilis (day 42) were observed, but no lactic acid bacteria were detected. Acidovorax and Variovorax species might play some role in GJ fermentation. Further studies on these bacteria are necessary.

• 한국식품영양과학회지
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• 제42권11호
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• pp.1717-1726
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• 2013

본 연구에서는 김치 유산균 starter의 사용이 김치의 품질특성과 건강기능성에 미치는 영향을 확인하고자 single starter 김치(Lb. plantarum pnuK, Lb. plantarum 3099K, Leu. mesenteroides pnuK), mixed starter 김치(Lb. plantarum pnu/Leu. mesenteroides pnuK, Lb. plantarum 3099/Leu. mesenteroides pnuK), 자연 발효 김치(NK)를 제조하여 $15^{\circ}C$에서 6일간 발효하며 실험하였다. pH 및 산도는 발효 초기에는 차이가 없었으나 발효 2일부터 starter 접종 김치에서 빠른 변화를 보였다. 총호기성 세균과 Lactobacillus sp.는 발효가 진행될수록 비슷하게 증가하였으나 Leuconostoc sp.는 Leu. mesenteroides를 starter로 접종한 김치에서 높게 나타났다. 관능검사 결과 starter를 첨가한 김치에서 관능적 만족도가 높게 나타났으며, 혼합 starter 김치에서 만족도가 더 높았다. DPPH 및 hydroxyl radical 소거능 측정 결과, starter를 첨가한 김치에서 높은 항산화 효과를 보였다. MTT assay 결과, HCT-116 및 HT-29 세포에서 NK는 각각 63.4, 51.9%를 나타내었고 Lb. plantarum pnuK는 각각 77.1, 68.8%의 암세포 성장 저해율을 보였다. 따라서 starter 첨가 시 항산화 및 항암효과가 증가되며, 단일 starter 김치가 혼합 starter 김치보다 높은 기능성을 가지는 것으로 나타났다. 그중 새로 분리 동정된 Lb. plantarum pnu를 이용한 김치에서의 높은 대장암 세포 성장억제 효과를 확인하였다. Apoptosis 유도에 관련된 Bcl-2 및 Bax, 종양 억제에 관련된 p53 및 p21, 염증에 관련된 iNOS 및 COX-2 유전자 발현은 starter 첨가 김치에서 자연발효 김치보다 모두 apoptosis 유도 작용과 염증 및 종양을 억제하는 효과가 높게 나타났다. 가장 높은 효과를 보인 것은 Lb. plantarum pnuK이었으며 단일 starter 김치에서 혼합 starter 김치보다 효과가 높았다. 이상의 결과로 starter를 이용해 관능적 품질이 우수하고 기능성이 증진된 김치를 제조할 수 있을 것으로 기대된다.

• 한국식품저장유통학회지
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• 제23권6호
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• pp.811-818
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• 2016

본 연구는 장류용 주요 콩 품종별, 유용발효미생물인 Bacillus subtilis HJ18-9 첨가 유무에 따른 청국장의 이화학적인 특징과 맛에 관여하는 아미노산 및 유기산 구성을 비교하고자 하였다. 원료콩 으로는 대원, 대풍, 새단백, 태광을 사용하였다. 원료콩(찐콩), starter를 첨가하지 않은 전통방법으로 제조한 청국장(청국장 c)과 starter를 첨가하여 제조한 청국장(청국장 t)의 수분함량은 62.45~67.12, 63.28~67.14, 64.50~66.87%이었으며, 아미노태 질소는 6.53~24.25, 27.63~122.09, 37.29~133.48 mg%, 암모니아태 질소는 26.92~47.95, 45.45~156.36, 28.02~121.13 mg%로 나타났다. 유리아미노산 함량은 원료콩이 청국장보다 감칠맛을 내는 glutamic acid, aspartic acid이 더 많은 반면, 쓴맛을 내는 valine, methionine, isoleucine, leucine, phenylalanine은 starter 첨가 유무에 관계없이 청국장이 원료콩보다 더 많은 양이 검출되었다. 유기산은 원료 콩에서 청국장으로 발효되면서 oxalic acid와 citric acid의 경우 그 함량이 감소하였고, malic acid, lactic acid, acetic acid, succinic acid는 그 함량이 증가하였다. SDS-page 확인 결과 원료콩에서는 넓은 분포로 band가 보였지만 청국장의 경우 분자량이 큰 단백질이 사라지고 작은 분자량이 증가하는 것을 확인할 수 있었다. 총 균수는 원료콩, 청국장 c 및 청국장 t의 경우, 각각 3.80~5.67, 8.14~8.85, 7.48~8.46 log CFU/mL의 범위로 나타났다. 이상의 결과로 콩품종에 따라 발효정도에 차이를 보이는 것과, starter첨가에 따른 품종별 발효양상이 다른 것을 확인하게 되었다. 특히, starter첨가 시, 다른 품종에 비해 새단백 청국장의 감칠맛과 연관된 glutamic acid와 aspartic acid의 함량이 증가하는 것으로 보아 주로 두부제조용으로 이용되었던 새단백의 용도다양화가 가능 할 것으로 판단된다. 본 내용은 콩품종 및 starter 첨가에 따른 청국장의 이화학적인 특징과 맛에 관여하는 아미노산 및 유기산 구성을 비교하여 청국장의 품질을 향상시키는데 필요한 기초자료로써 향후, 기능성 콩발효식품 및 콩품종 이용다양화에 활용 될 수 있을 것으로 기대된다.

• Journal of Microbiology and Biotechnology
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• 제25권5호
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• pp.559-568
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• 2015

Kimchi is a traditional Korean vegetable product that is naturally fermented by various microorganisms present in the raw materials. Among these microorganisms, lactic acid bacteria dominate the fermentation process. Natural fermentation with unsterilized raw materials leads to the growth of various lactic acid bacteria, resulting in variations in the taste and quality of kimchi, which may make it difficult to produce industrial-scale kimchi with consistent quality. The use of starter cultures has been considered as an alternative for the industrial production of standardized kimchi, and recent trends suggest that the demand for starter cultures is on the rise. However, several factors should be carefully considered for the successful application of starter cultures for kimchi fermentation. In this review, we summarize recent studies on kimchi starter cultures, describe practical problems in the application of industrial-scale kimchi production, and discuss the directions for further studies.

• 동아시아식생활학회지
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• 제18권1호
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• pp.87-94
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• 2008

In this study, a nanatural fermentation starter formulation was developed for manufacturing bread products by substituting baker's yeast with naturally fermented raisin extract and sourdough. Four experimental groups containing 2.5, 5.0, 7.5, 10% naturally fermented raisin extract per 2,000 g of flour were compared based on quality characteristics, including the fermentation power on dough expansion, specific volume, baking loss, water activity, color, textural characteristics, and internal surface appearance. The activities of the naturally fermented raisin extract were examined in terms of pH changes, total titratable acidity, brix, and viable yeast counts. The raisin extract, which was cultured for 7 days at 30$^{\circ}C$, smelled of alcohol and produced $CO_2$. Yeast were also found in the extract after separation. As the incubation time of the raisin extract and sourdough increased, pH decreased, while total titratable acidity increased. The brix of the raisin extract increased until the $2^{nd}$ day of fermentation, and viable yeast counts increased until the $5^{th}$ day however, these gradually decreased by the $7^{th}$ day. The fermenting power on dough expansion increased in the bread with increasing incubation time. The bread samples containing 7.5% and 10% raisin extract had significantly higher specific volumes than the other samples. Baking loss was minimal with the 2.5% extract substitution. In analyzing the crumb, water activity, redness, and yellowness were highest in the 10.0% raisin extract bread samples, and lightness was maximal in the 5.0% group. In terms of textural characteristics, hardness was lowest with the 2.5% extract substitution. Gumminess, springiness, and chewiness were not significantly different among the bread samples. Cohesiveness was highest at the 7.5% extract substitution level, and resilience was lowest at the 10% level. In conclusion, based on the results, a natural fermentation starter formulated with 2.5% naturally fermented raisin extract (1 part raisins and 1.5 parts water) and 70% sourdough (1 part rye flour and 1 part water) has high potential as a baker's yeast substitute for making naturally fermented bread.

• Journal of Microbiology and Biotechnology
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• 제30권8호
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• pp.1184-1194
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• 2020

Melanin is a major factor that darkens skin color as one of the defense systems to prevent the harmful effects of UV light. However, darkened skin from the localized or systemic accumulation of melanin is viewed in many cultures as an esthetic problem. Consequentially, searching for anti-melanogenic agents from natural sources is very popular worldwide. Previous screening of fermented rice products, obtained from various rice cultivars fermented with different sources of loog-pang (Thai traditional fermentation starter), revealed that the highest ability to reduce the melanin content in B16F10 melanoma cells was from unpolished black rice fermented with a defined starter mixture of microbes isolated from loog-pang E11. The aim of this study was to investigate the mechanism of the fermented unpolished black rice (FUBR) on the inhibition of melanogenesis in B16F10 melanoma cells. The strongest reduction of cellular melanin content was found in the FUBR sap (FUBRS). The melanin reduction activity was consistent with the significant decrease in the intracellular tyrosinase activity. The FUBRS showed no cytotoxic effect to B16F10 melanoma or Hs68 human fibroblast cell lines. It also significantly reduced the transcript and protein expression levels of tyrosinase, tyrosinase-related protein 1 (TYRP-1), TYRP-2, and microphthalmia-associated transcription factor. Furthermore, it induced a significantly increased level of phosphorylated ERK, p38 and Akt signaling pathways, which likely contributed to the negative regulation of melanogenesis. From these results, a model for the mechanism of FUBRS on melanogenesis inhibition was proposed. Moreover, these results strongly suggested that FUBRS possesses anti-melanogenesis activity with high potential for cosmeceutical application as a skin depigmenting agent.

• Journal of Ginseng Research
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• 제42권1호
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• pp.57-67
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• 2018

Background: Ginseng contains many small metabolites such as amino acids, fatty acids, carbohydrates, and ginsenosides. However, little is known about the relationships between microorganisms and metabolites during the entire ginseng fermentation process. We investigated metabolic changes during ginseng fermentation according to the inoculation of food-compatible microorganisms. Methods: Gas chromatography mass spectrometry (GC-MS) datasets coupled with the multivariate statistical method for the purpose of latent-information extraction and sample classification were used for the evaluation of ginseng fermentation. Four different starter cultures (Saccharomyces bayanus, Bacillus subtilis, Lactobacillus plantarum, and Leuconostoc mesenteroide) were used for the ginseng extract fermentation. Results: The principal component analysis score plot and heat map showed a clear separation between ginseng extracts fermented with S. bayanus and other strains. The highest levels of fructose, maltose, and galactose in the ginseng extracts were found in ginseng extracts fermented with B. subtilis. The levels of succinic acid and malic acid in the ginseng extract fermented with S. bayanus as well as the levels of lactic acid, malonic acid, and hydroxypruvic acid in the ginseng extract fermented with lactic acid bacteria (L. plantarum and L. mesenteroide) were the highest. In the results of taste features analysis using an electronic tongue, the ginseng extracts fermented with lactic acid bacteria were significantly distinguished from other groups by a high index of sour taste probably due to high lactic acid contents. Conclusion: These results suggest that a metabolomics approach based on GC-MS can be a useful tool to understand ginseng fermentation and evaluate the fermentative characteristics of starter cultures.

• 한국축산식품학회지
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• 제31권4호
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• pp.513-520
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• 2011

In order to develop a new starter culture for fermented milk, Lactobacillus fermentum LC272 was isolated from raw milk and its physiological characteristics were investigated. The vitamin $K_2$ concentration of L. fermentum LC272 was $184.94{\mu}g/L$ in Rogosa medium and $63.93{\mu}g/L$ in the reconstituted skim milk. The optimum growth temperature for L. fermentum LC272 was determined to be $40^{\circ}C$ and it took 24 h for the pH to reach 5.2 under this condition. L. fermentum LC272 was more sensitive to rifampicin relative of the other 15 different antibiotics tested, and showed most resistance to streptomycin. L. fermentum LC272 showed higher activities to leucine arylamidase and acid phosphatase. It was comparatively tolerant to bile juice and acid and displayed high resistance against Salmonella Typhimurium and Staphylococcus aureus with rates of 82.9 and 86.3% respectively. These results demonstrated that L. fermentum LC272 could be an excellent starter culture for fermented milk with high levels of vitamin $K_2$ production.