• 미생물학회지
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• 제55권3호
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• pp.293-295
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• 2019

메주로부터 분리한 Enterococcus faecalis DM01 균주는 8종의 항생제(ampicillin, chloramphenicol, ciprofloxacin, erythromycin, gentamicin, penicillin G, tetracycline, vancomycin) 저항성, 바이오필름 및 용혈현상을 나타내지 않았다. GC 함량 37.68%, 2,785,968 bp 크기의 단일 chromosome을 보유하고 있는 DM01 균주의 유전체 정보는 콩발효식품 제조용 종균 적용에 요구되는 항생물질 저항성, 바이오필름 및 용혈현상 관련의 안전성을 뒷받침하는 것으로 확인되었다.

• Applied Biological Chemistry
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• 제32권3호
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• pp.295-302
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• 1989

발효식품인 장류의 제조 중 원료처리에 대한 기초자료를 제공하고자 생대두, 수침대두, 볶은대두 및 증자대두를 제조하여 이것과 Asp. oryzae, Asp. niger, Asp. awamori 및 자연 발효균을 접종시켜 제조한 쌀고오지 및 식염을 각각 60 : 30 : 10(W/W)의 비율로 혼합하여 생대두 된장$(S_0)$, 수침대두 된장$(S_1)$, 볶은대두 된장$(S_2)$ 및 증자대두$(S_3)$을 제조하면서 발효과정 중 amylase, protease, lipase 및 lipoxygenase 활성도의 변화를 측정한 결과 다음과 같은 결론을 얻었다. 콩된장 제조중 접종시킨 미생물 상호간의 amylase 활성도는 자연 발효균>Asp. oryzae>Asp. awamori>Asp. niger 순이었고, 각 처리대두에 따른 활성도는 $S_0>S_1>S_2>S_3$구 순이었으며, protease 활성도는 자연 발효균>Asp. niger>Asp. oryzae>Asp. awamori순 이었으며, 각 처리구에 따른 활성도는 $S_3>S_2>S_1>S_0$ 구 순이었다. Lipase 활성도는 미생물 상호간에 별 차이가 없었고, 처리구에 따른 그 활성도 크기는 $S_0>S_1>S_3>S_2$ 구 순이었으며 lipoxygenase 활성도는 콩된장 제조 중 접종시킨 미생물 상호간에 있어서는 자연 발효균>Asp. oryzae>Asp. awamori>Asp. niger순 이었고, 각 시험구간에는 $S_0>S_1>S_3>S_2$구 순이었다.

• Food Science and Biotechnology
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• 제15권1호
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• pp.96-101
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• 2006

Isoflavone distribution and ${\beta}$-glucosidase activity in cheonggukjang, a traditional Korean whole soybean-fermented food prepared with or without addition of Bacillus subtilis, were analyzed every 6 hr for 36 hr. Thermal cooking of raw-soaked soybeans significantly increased ${\beta}$-glucoside isoflavone level by 57.1 % and decreased malonyl-${\beta}$-glucosides by 57.6% (p<0.05). Consistent changes of isoflavone profiles in cheonggukjang without B. subtilis addition (COB) and samples with addition of B. subtilis (CWB) were not observed during 36 hr fermentation. ${\beta}$-Glucosides of isoflavones are major forms in both COB and CWB. ${\beta}$-Glucosidase activity in cheonggukjang decreased significantly compared to that of soaked soybeans due to thermal denaturation, while recovery of enzyme activity in COB was observed. Two new unidentified peaks were detected, and their relative peak areas in CWB were significantly larger than those in COB with increasing fermentation period (p<0.05), which indicates both peaks could be associated with fermentation metabolites.

• Animal Bioscience
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• 제35권8호
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• pp.1195-1204
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• 2022

Objective: The objective of this study was to investigate the in vitro fermentation profiles of different soybean oligosaccharides (SBOs) and their effects on skatole production and cecal microbiota of broilers. Methods: Five SBOs with varying main component contents were fermented using an in vitro batch incubation inoculated with broiler cecal microbiota. Gas production was recorded automatically, skatole, indole and short-chain fatty acids (SCFAs) were determined using high-performance liquid chromatography, and microbial changes were analyzed using 16S DNA gene sequencing. Results: The addition of SBOs increased (p<0.05) gas production, suggesting bacterial growth-stimulating activities. In addition, the concentrations of indole were significantly (p<0.05) decreased after SBO supplementation, and SBO III, with higher sucrose and stachyose contents, decreased (p<0.05) the skatole level. Our results also revealed that the fermentation of SBOs by cecal microbiota produced (p<0.05) SCFAs, which were dominated by propionic acid, butyrate acid and lactic acid compared to the control. In addition, SBO III increased (p<0.05) the abundance of Firmicutes and Subdoligranulum and decreased that of Bacteroides. Conclusion: These results suggest that SBOs with higher sucrose and stachyose contents are promising prebiotics in modulating gut microbiota and reducing odor emission in broilers.

• Mycobiology
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• 제50권6호
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• pp.408-419
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• 2022

Filamentous fungi that could be classified into Aspergillus flavus/oryzae were isolated from traditionally fermented meju commercially available in Korea. The samples were analyzed for aflatoxin B1 and ochratoxin A contamination by HPLC; however, no toxin was detected. In addition, fungal and bacterial metagenomic sequencing were performed to analyze the microbial distribution in the samples. The results revealed that the distribution and abundance of fungi and bacteria differed considerably depending on the production regions and fermentation conditions of the meju samples. Through morphological analysis, ITS region sequencing, and assessment of the aflatoxin-producing ability, a total of 32 A. flavus/oryzae strains were identified. PCR analysis of six regions with a high mutation frequency in the aflatoxin gene cluster (AGC) revealed a total of six types of AGC breaking point patterns. The A. flavus/oryzae strains did not exhibit the high amylase activity detected in the commercial yellow koji strain (starter mold). However, their peptidase and lipase activities were generally higher than that of the koji isolates. We verified the safety of the traditionally fermented meju samples by analyzing the AGC breaking point pattern and the enzyme activities of A. flavus/oryzae strains isolated from the samples. The isolated strains could possibly be used as starter molds for soybean fermentation.

• Asian-Australasian Journal of Animal Sciences
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• 제23권5호
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• pp.598-606
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• 2010

This study investigated the nutritional quality of soybean meal (SBM) fermented by Aspergillus ($FSBM_A$) and/or followed by Lactobacillus fermentation ($FSBM_{A+L}$). Both fermented products significantly improved protein utilization of SBM with higher trichloroacetic acid (TCA) soluble true protein content, in vitro protein digestibility and available lysine content, especially in $FSBM_{A+L}$. Moreover, $FSBM_{A+L}$ produced a huge amount of lactic acid resulting in lower pH as compared to the unfermented SBM or soybean protein concentrate (SPC) (p<0.05). $FSBM_A$ and $FSBM_{A+L}$ raised 4.14% and 9.04% of essential amino acids and 5.38% and 9.37% of non-essential amino acids content, respectively. The ${\alpha}$-galactoside linkage oligosaccharides such as raffinose and stachyose content in $FSBM_A$ and $FSBM_{A+L}$ decreased significantly. The results of soluble protein fractions and distribution showed that the ratio of small protein fractions (<16 kDa) were 42.6% and 63.5% for $FSBM_A$ and $FSBM_{A+L}$, respectively, as compared to 7.2% for SBM, where the ratio of large size fractions (>55 kDa, mainly ${\beta}$-conglycinin) decreased to 9.4%, 5.4% and increased to 38.8%, respectively. There were no significant differences in ileal protein digestibility regardless of treatment groups. SPC inclusion in the diet showed a better protein digestibility than the SBM diet. In summary, soybean meal fermented by Aspergillus, especially through the consequent Lactobacillus fermentation, could increase the nutritional value as compared with unfermented SBM and is compatible with SPC.

• 한국영양학회:학술대회논문집
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• 한국영양학회 2001년도 춘계연합학술대회 초록
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• pp.258.2-258
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• 2001

• Asian-Australasian Journal of Animal Sciences
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• 제30권2호
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• pp.171-180
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• 2017

Objective: This study investigated the association of enzyme-producing microbes and their enzymes with starch and hemicellulose degradation during fermentation of total mixed ration (TMR) silage. Methods: The TMRs were prepared with soybean curd residue, alfalfa hay (ATMR) or Leymus chinensis hay (LTMR), corn meal, soybean meal, vitamin-mineral supplements, and salt at a ratio of 25:40:30:4:0.5:0.5 on a dry matter basis. Laboratory-scale bag silos were randomly opened after 1, 3, 7, 14, 28, and 56 days of ensiling and subjected to analyses of fermentation quality, carbohydrates loss, microbial amylase and hemicellulase activities, succession of dominant amylolytic or hemicellulolytic microbes, and their microbial and enzymatic properties. Results: Both ATMR and LTMR silages were well preserved, with low pH and high lactic acid concentrations. In addition to the substantial loss of water soluble carbohydrates, loss of starch and hemicellulose was also observed in both TMR silages with prolonged ensiling. The microbial amylase activity remained detectable throughout the ensiling in both TMR silages, whereas the microbial hemicellulase activity progressively decreased until it was inactive at day 14 post-ensiling in both TMR silages. During the early stage of fermentation, the main amylase-producing microbes were Bacillus amyloliquefaciens (B. amyloliquefaciens), B. cereus, B. licheniformis, and B. subtilis in ATMR silage and B. flexus, B. licheniformis, and Paenibacillus xylanexedens (P. xylanexedens) in LTMR silage, whereas Enterococcus faecium was closely associated with starch hydrolysis at the later stage of fermentation in both TMR silages. B. amyloliquefaciens, B. licheniformis, and B. subtilis and B. licheniformis, B. pumilus, and P. xylanexedens were the main source of microbial hemicellulase during the early stage of fermentation in ATMR and LTMR silages, respectively. Conclusion: The microbial amylase contributes to starch hydrolysis during the ensiling process in both TMR silages, whereas the microbial hemicellulase participates in the hemicellulose degradation only at the early stage of ensiling.

• 한국미생물·생명공학회지
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• 제31권3호
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• pp.257-263
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• 2003

고체상태배양에서 섬유소분해효소의 고 생산을 위해 기질로서 다양한 섬유순폐기물을 검토한 결과, 주정박과 볏짚을 1:1의 혼합기질로 사용하였을 때 13.98 FPA를 얻었다. 효소생산을 높이기 위해 주정박과 볏짚의 혼합기질에 질소원으로서 콩비지를 1:1:1로 혼합하였을 때 15.22 FPA의 효소활성을 얻을 수 있었다. 이때의 최적의 함수율, pH, 온도는 각각 70%, 5.0, 3$0^{\circ}C$이었다. 최적배양조건에서 배양 5일째 FPA, CMCase, Xylanase, $\beta$-glucosidase 및 Avicelase의 효소활성은 각각 15.22, 69.1, 83.9, 29.2 및 4.2 unit/g-SDW이었다. T. harzianum FJI의 섬유소폐기물을 이용한 고체상 태배양의 경제적인 효소생산은 섬유소폐기물의 생물학적 당화기술에 크게 기여할 것이다.

• 한국식품영양과학회지
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• 제31권4호
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• pp.713-716
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• 2002

발효기간동안 된장에서 검출된 biogenic amine은 putrescine cadaverine, tryptamine $\beta$-phenylethylamine, spermidine, spermine, histamine, tyramine 및 agmatine 등으로 총 9가지 종류이며 , 검출된 biogenic amine 중 agmatine의 함량이 가장 높은 것으로 나타났다. 된장의 발효기간에 따른 biogenic amine함량은 종류에 따라 증가 혹은 감소하는 경향을 보였다. 감마선 조사에 의해 발효기간 중 대부분의 biogenic amine함량이 20~60% 가량 유의적(p<0.05)으로 감소하였는데, 이 중 spermine 및 agmatine은 대조구와 유의적인 차이를 보이지 않아 감마선 조사에 의한 영향을 받지 않는 것으로 나타났다. 따라서, 감마선 조사기술은 된장숙성 중의 biogenic amine 생성을 억제시킬 수 있는 것으로 나타났다.