• 한국식품영양학회지
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• 제23권2호
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• pp.178-185
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• 2010

Barley leaves tea white bread were prepared by the addition of 0.005, 0.010, 0.015, and 0.020% hemicellulase to flour of the basic formulation. The experiments and control were then compared in terms of quality characteristics, including pH, total titratable acidity, fermentation power of dough expansion, specific volume, baking loss, moisture content, color, textural characteristics, internal surface appearances, and sensory qualities in order to determine the optimal ratio of hemicellulase in the formulation. There were no significant differences in pH and total titratable acidity of dough and bread among the experiments. Fermentation power of dough expansion were increased as incubation time increased. Bread made by the addition of hemicellulase had significantly higher specific volume than the control group. However, lightness and yellowness showed the reverse effect. Greenness was not significantly different among the samples. Baking loss was the highest at the 0.020% addition level, and moisture content was maximal with the 0.010% addition, while the lowest in the control bread samples. As hemicellulase contents increased, harness and fracturability decreased. Resilience was maximal with the 0.015% addition, and was minimal in the 0.005% group. In the sensory evaluation, color, flavor, softness, overall acceptability, barley leaves flavor, delicious taste, astringency, bitterness, and off-flavor were not significantly different among the samples. In coclusion, the results indicate that adding 0.010% hemicellulase in barley leaves tea white bread is optimal for quality and provides a product with reasonably high overall acceptability.

• 한국식품영양과학회지
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• 제32권2호
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• pp.181-184
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• 2003

G. persimonensis-KJ145를 차용하여 BC 생산과 식초생산에 미치는 에탄올의 영향을 조사하였다. 그 결과 사과쥬스배지에 에탄올을 2%(v/v) 첨가하였을 때 BC의 생산성이 가장 좋았으며, 7%(v/v)를 첨가하였을 때 총산의 함량이 가장 높았다. BC와 식초를 동시 생산하기 위해서는 에탄올을 5%(v/v) 첨가하는 것이 가장 좋을 것으로 생각되며 발효과정 중의 식초 품질 변화에 대한 보다 자세한 연구가 요구되었다. BC와 식초 생산에 가장 효과적인 질소원은 CSL인 것으로 조사되었고 최적 농도는 15%(w/v)이었다. 배양시간의 영향을 조사한 결과 14일간 배양하는 것이 가장 많은 양의 BC를 생산하였으며, 최적조건에서 생산되는 BC 생산량은 7.55 g/L이었다.

• Journal of Microbiology and Biotechnology
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• 제24권6호
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• pp.781-787
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• 2014

2-Ketogluconic acid production by Klebsiella pneumoniae is a pH-dependent process, strictly proceeding under acidic conditions. Unfortunately, cell growth is inhibited by acidic conditions, resulting in low productivity of 2-ketogluconic acid. To overcome this deficiency, a two-stage fermentation strategy was exploited in the current study. During the first stage, the culture was maintained at neutral pH, favoring cell growth. During the second stage, the culture pH was switched to acidic conditions favoring 2-ketogluconic acid accumulation. Culture parameters, including switching time, dissolved oxygen levels, pH, and temperature were optimized for the fed-batch fermentation. Characteristics of glucose dehydrogenase and gluconate dehydrogenase were revealed in vitro, and the optimal pHs of the two enzymes coincided with the optimum culture pH. Under optimum conditions, a total of 186 g/l 2-ketogluconic acid was produced at 26 h, and the conversion ratio was 0.98 mol/mol. This fermentation strategy has successfully overcome the mismatch between optimum parameters required for cell growth and 2-ketogluconic acid accumulation, and this result has the highest productivity and conversion ratio of 2-ketogluconic and produced by microorganism.

• Preventive Nutrition and Food Science
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• 제7권4호
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• pp.397-404
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• 2002

Soybean curd residue (SCR) was fermented by lactic acid bacteria, Lactobacillus rhamnosus LS and Entercoccus faecium LL, isolated from SCR. The pH, titratable acidify and viable cell counts were determined from the fermented SCR to evaluate the lactic acid production and growth of lactic acid bacteria. Optimal amounts of pretense enzyme and glucose, and ideal fermentation time for SCR fermentation were estimated by response surface methodology (RSM). Raw SCR fermented by indigenous microorganisms had 0.78 % titratable acidity, The acid production in SCR fermented by L. rhamnosus LS was greatly enhanced by the addition of glucose and lactose. However only glucose increased acid production by Ent. faecium LL. The proof test of SCR fermentation demonstrated that similar results for titratable acidity, tyrosine content and viable cell counts to that predicted could be obtained by the at optimized fermentation conditions. In the presence of 0.029 % (w/w) pretense enzyme and 0.9% (w/w) glucose, the SCR fermented by Ent. faecium LL showed 1.07% (w/v) of titratable acidity, 1.02 mg% tyrosine content and 2$\times$10$^{9}$ (cfu/g) of viable cell counts. With the SCR fortified with 0.033% pretense enzyme and 1.7% glucose, L. rhamnosus LS showed 1.8% (w/v) of titratable acidity, 0.92 mg% of tyrosine content and 2$\times$10$^{9}$ (cfu/g) of viable cell counts.

• Asian-Australasian Journal of Animal Sciences
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• 제31권8호
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• pp.1205-1212
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• 2018

Objective: The aim of this experiment was to evaluate the effects of different dietary ratio of metabolizable glucose (MG) to metabolizable protein (MP) on growth performance, blood metabolites, rumen fermentation parameters and the ruminal microbial community of 8 to 10-month-old heifers. Methods: A total of 24 Holstein heifers weighing an average of 282.90 kg (8 month of age) were randomly assigned to four groups of six. The heifers were fed one of four diets of different dietary MG/MP (0.97, 1.07, 1.13, and 1.26). Results: The results showed that the ratio of MG/MP affected the growth performance, blood metabolites, rumen fermentation parameters and the ruminal microbial community of heifers. The average daily gain of heifers was enhanced by increasing the ratio of MG/MP (p<0.05). The concentration of blood urea nitrogen, cholesterol, and low density lipoprotein cholesterol as well as the concentration of total volatile fatty acid in the rumen fluid of heifers decreased with the improvement in the ratio of dietary MG/MP (p<0.05). However, the relative amount of Ruminococcus albus and Butyrivibrio fibrisolvens in the rumen of heifers was increased significantly (p<0.05) when the dietary MG/MP increased. At the same time, with the improvement in dietary MG/MP, the amount of Fibrobacter succinogenes increased (p = 0.08). Conclusion: A diet with an optimal ratio (1.13) of MG/MP was beneficial for the improvement of growth, rumen fermentation, dietary protein and energy utilization of 8 to 10-month-old dairy heifers in this experiment.

• 한국식품위생안전성학회지
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• 제32권6호
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• pp.531-535
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• 2017

본 연구에서는 김치로부터 L. mesenteroides CJNU0041을 분리하여 16S rRNA 염기서열 분석을 통해, 동정하였으며, ${\beta}$-glucosidase 활성이 우수한 것으로 나타났다. L. mesenteroides CJNU0041를 이용한 브로콜리 발효 동안 생균수와 pH 및 ${\beta}$-glucosidase 활성에 대해 분석한 결과, 발효 시간은 48 hours이 적당한 것으로 판단되었다. 또한, 발효 후 생물 전환이 일어남을 HPLC 분석을 통해 확인하였다. 그리고, L. mesenteroides CJNU0041의 브로콜리 발효물에서 C. difficile에 대한 생육 억제 효과를 확인 할 수 있었다. 따라서, 본 연구를 통해 분리된 신규 L. mesenteroides CJNU0041을 C. difficile의 생육 제어를 위한 유산균 제재화가 가능할 것으로 판단되며, 브로콜리 발효물도 다양한 식품에 적용이 가능할 것으로 사료된다.

• Journal of Microbiology and Biotechnology
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• 제27권4호
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• pp.701-708
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• 2017

This study was conducted to evaluate the hyaluronidase (HAase) inhibition activity of Asparagus cochinchinesis (AC) extracts following fermentation by Weissella cibaria through response surface methodology. To optimize the HAase inhibition activity, a central composite design was introduced based on four variables: the concentration of AC extract ($X_1$: 1-5%), amount of starter culture ($X_2$: 1-5%), pH ($X_3$: 4-8), and fermentation time ($X_4$: 0-10 days). The experimental data were fitted to quadratic regression equations, the accuracy of the equations was analyzed by ANOVA, and the regression coefficients for the surface quadratic model of HAase inhibition activity in the fermented AC extract were estimated by the F test and the corresponding p values. The HAase inhibition activity indicated that fermentation time was most significant among the parameters within the conditions tested. To validate the model, two different conditions among those generated by the Design Expert program were selected. Under both conditions, predicted and experimental data agreed well. Moreover, the content of protodioscin (a well-known compound related to anti-inflammation activity) was elevated after fermentation of the AC extract at the optimized fermentation condition.

• 한국미생물·생명공학회지
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• 제20권4호
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• pp.470-476
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• 1992

Nocardia mediterranei NCK-4를 동결건조시 생존도에 미치는 영향을 검토하기 위해 보호물질의 종류와 농도, cell 농도 및 건조시간에 대해 실험한 data를 반응표면분석법을 활용하여 분석한 결과, 추정된 최대치의 생존도는 39.3이었으며, 이 최적 조건은 sucrose 11.6(v/v), cell 농도 $1.16{\times}10^{11}$(CFU/ml), 건조 시간 6.18hrs로 나타났다. N.mdeiterranei NCK-4를 동결건조하여 rehydration한 후 계대배양없이 starter cell로서 발효생산에 사용가능성을 검토한 결과, 전배양시 대조군인 FVM(frozen vegetative mycelium)과 거의 비슷하게 cell의 농도를 맞추어 발효함으로써 가능하다. 따라서 이 starter cell은 lyophilization 후 약 18개월간 저장하여 안정하게 사용할 수 있었다.

• 한국작물학회지
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• 제60권2호
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• pp.174-179
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• 2015

이 연구는 맥류 곡실발효사료 조제를 위한 적정 수확시기 및 수확시기별 곡실 발효사료의 발효품질을 평가하기 위하여 실시하였다. 그 결과, 알곡의 수분함량은 수확시기가 늦어짐에 따라 감소하는 경향을 보였고, 이삭비율과 천립중은 맥종별 모두 출수 후 일수가 경과됨에 따라 높아지는 경향을 보였다. 알곡수량은 맥종 모두 수확시기가 늦어질수록 유의적으로 증가하는 경향을 보였다(p<0.05). 조단백질 함량은 수확시기가 늦어질수록 맥종 모두 높아지는 경향을 보였고, 조섬유함량은 낮아지는 경향을 보였으며, 조지방과 조회분 함량은 비슷하거나 약간 낮아지는 경향을 보였지만 통계적인 유의성은 없었다. 곡실사료의 발효 전후 사료가치를 비교하여 보면, 일반성분들이 발효를 거친 후 약간 증가되는 경향은 있었지만 유의적인 차이는 나타나지 않았다. 발효품질 면에서는 공시한 맥종 모두 수확시기가 늦어질수록 pH는 높아지고, 젖산함량은 유의적으로 낮아지는 경향을 보였다(p<0.05). 초산함량은 맥종 모두 수확시기에 따른 차이를 나타내지 않았고, 낙산은 검출되지 않았다. 따라서 수량과 발효품질을 고려할 때, 맥류 곡실사료 조제를 위해서는 겉보리과 쌀보리는 출수 후 35일, 밀은 출수 후 40~45일에 수확하는 것이 적당한 것으로 판단된다.

• 한국식품저장유통학회지
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• 제17권3호
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• pp.320-327
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• 2010

연근즙 첨가수준에 따라 백김치를 제조한 후 $5^{\circ}C$에서 4주간 저장하면서 숙성 중의 이화학적, 관능적 특성을 조사하였다. 연근즙의 첨가수준이 증가할수록 pH는 감소, 산도는 반대로 증가하는 경향을 보였고 숙성기간 중에도 같은 경향을 보였다. 탁도는 첨가수준이 증가할수록 증가함을 볼 수 있었으며, 숙성 2주까지는 대조군의 비해 첨가군의 경우 탁도가 증가하는 경향을 보였으나 숙성 3주, 4주에서는 약간 더 감소하는 경향을 보였다. 색도 L 값과 a 값은 연근즙 첨가수준이 증가할수록 감소하였고, b 값은 증가하였다. 환원당은 연근즙 3%와 6% 첨가군의 경우 증가하였다가 연근즙 9%와 12% 첨가군의 경우 감소하는 경향을 보였다. 숙성기간에 따라서는 감소하는 경향을 볼 수 있었다. 비타민 C함량은 대조군보다 연근즙 첨가군의 경우 모든 숙성기간에서 더 높게 나타났다. 경도는 대조군보다는 모든 첨가군의 경우 약간 높은 값을 보였지만 첨가수준에 따른 일정한 경향은 보이지 않았다. 숙성기간에 따른 변화로는 숙성기간이 증가할수록 감소하는 경향을 보였다. 관능검사결과에서는 연근즙 6% 첨가군의 경우 색, 냄새, 아삭아삭한 정도 및 전체적인 기호도가 가장 높게 나타나 백김치에 연근즙의 첨가수준이 6%정도가 적절한 것으로 나타났다.