• 한국식품과학회지
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• 제30권6호
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• pp.1388-1393
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• 1998

젖산균 및 효모를 이용하여 전통안동식혜를 제조하여 저장하는 동안 질소화합물 및 아미노산의 변화를 조사하였다. 숙성기간동안 조단백질의 함량은 주발효 기간인 4일까지는 증가하였으며, 아미노태질소는 시간이 경과할수록 증가하였으며 2일째 37.50 mg였으며 이때 식혜의 맛이 가장 좋았다. 수용성 및 염용성 단백질은 시간이 경과함에 따라 점차 감소하였고 주요 아미노산은 proline 및 aspartic acid였으며 methionine은 시간이 경과함에 따라 점차 증가하였으나 lysine은 감소하였다. 수용성 및 염용성 단백질의 아미노산 조성은 총 17종이었고, 이 중 glutamine acid 및 aspartic acid의 함량이 가장 많았다. 염용해성 단백질의 경우 arginine은 시간이 경과함에 따라 점차 증가하였다.

• KSBB Journal
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• 제8권1호
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• pp.1-9
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• 1993

The acetone-butanol fermentation by C. acetobutylicum has gained increasing attention for the following reasons. First, the finite supply of petrochemical resources, combined with increasing concern over global environmental effects and the unstable nature of the price of petroleum has renewed interest in the development of fermentation technology that allows utilzation of biomass wastes for the production of alcohol. Second, it serves as excellent model system for understading the regulation and molecular biology of tightly regulated complex primary metabolism, and for applications of metabolic engineering. In this review various aspects of acetone-butanol fermentation by C. acetobutylicm including strain and fermentation characteristics, enzyme regulation, and solvent formation mechanism, and product recovery and summarized.

• Journal of Microbiology and Biotechnology
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• 제7권2호
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• pp.95-100
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• 1997

• 한국식품과학회지
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• 제28권2호
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• pp.330-336
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• 1996

멥쌀, 찹쌀, 보리, 밀가루를 원료로 담금한 탁주 술덧의 발효 과정중 에탄올, pH, 총당, 색도, 미량알코올 등을 측정한 결과는 다음과 같다. 에탄올의 함량은 담금 직후 $0{\sim}1.2%$였으나 발효 16일에 $9.8{\sim}11.65$를 나타냈고 시험구중 주모 첨가의 멥쌀주가 다른 시험구에 비해 높았다. pH는 담금 직후 주모 무첨가의 멥쌀주가 pH 6.57로 시험구중 가장 높았으나 2일에는 $3.47{\sim}3.60$으로 저하되었고 시험구간의 차이는 없었다. 총산은 담금 후 2일에 급격히 증가하였으나 그 후 완만한 증가를 보였고 시험구중 밀가루주와 주모 무첨가의 멥쌀주가 다소 높았다. 총당은 담금 직후 $19.18{\sim}20.23%$였으나 $2{\sim}4$일에 $5.21{\sim}14.03%$로 감소하였고 시험구중 밀가루주가 높은 함량을 보였다. 환원당은 발효가 진행됨에 따라 감소하여 16일에 $0.2{\sim}0.5%$를 나타내었으나 시험구간 차이는 없었다. 색도는 시험구간에 다소 차이가 있었으나 발효 과정에 따라 L값(명도)이 낮아져 밝기가 저하됨을 알 수 있었고 보리쌀주는 시험구중 가장 낮은 결과를 나타냈다. 탁주 술덧에 함유하는 미량의 알코을로서 n-propanol ($nd{\sim}0.05\;mg/ml$), iso-butanol (0.02), iso-amyl alcohol ($nd{\sim}0.13$), n-hexanol ($nd{\sim}0.17$), n-heptanol ($nd{\sim}0.09$), and phenylethanol ($nd{\sim}0.02$)이 정량되었다.이들 알코올은 담금 직후에는 거출되지 않았으나 3일 이후 시험구에 따라 검출되었으며 함량은 발효 기간의 경과에 따라 미량 증가하였다.

• Biotechnology and Bioprocess Engineering:BBE
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• 제11권4호
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• pp.293-298
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• 2006

A study on the feasibility of using improved computer-controlled HPLC and GC systems was carried out to shorten the time needed for measuring levels of the substrates (glucose, maltose, and glycerol) and products (acetone, butanol ethanol, acetic acid, and butyric acid) produced by Clostridium saccharobutylicum DSM 13864 during direct fermentation of sago starch to solvent. The use of HPLC system with a single injection to analyse the composition of culture broth (substrates and products) during solvent fermentation was achieved by raising the column temperature to $80^{\circ}C$. Although good separation of the components in the mixture was achieved, a slight overlap was observed in the peaks for butyric acid and acetone. The shape of the peak obtained and the analysis time of 26.66 min were satisfactory at a fixed flow rate of 0.8mL/min. An improved GC system was developed, that was able to measure the products of solvent fermentation (acetone, butanol, ethanol, acetic acid, and butyric acid) within 19.28 min. Excellent resolution for each peak was achieved by adjusting the oven temperature to $65^{\circ}C$.

• Journal of Microbiology and Biotechnology
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• 제21권4호
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• pp.430-437
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• 2011

The effects of the agitation and aeration rates on the production of serratiopeptidase (SRP) in a 5-L fermentor (working volume 2-l) were systematically investigated using Serratia marcescens NRRL B-23112. The dissolved oxygen concentration, pH, biomass, SRP yield, and maltose utilization were all continuously measured during the course of the fermentation runs. The efficiencies of the aeration and agitation were evaluated based on the volumetric mass transfer coefficient ($K_La$). The maximum SRP production of 11,580 EU/ml with a specific SRP productivity of 78.8 EU/g/h was obtained with an agitation of 400 rpm and aeration of 0.075 vvm, which was 58% higher than the shake-flask level. The $K_La$ for the fermentation system supporting the maximum production (400 rpm, 0.075 vvm) was 11.3 $h^{-1}$. Under these fermentor optimized conditions, kinetic modeling was performed to understand the detailed course of the fermentation process. The resulting logistic and Luedeking-Piret models provided an effective description of the SRP fermentation, where the correlation coefficients for cell growth, SRP formation, and substrate consumption were 0.99, 0.94, and 0.84, respectively, revealing a good agreement between the model-predicted and experimental results. The kinetic analysis of the batch fermentation process for the production of SRP demonstrated the SRP production to be mixed growth associated.

• 한국식품과학회지
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• 제36권1호
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• pp.92-96
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• 2004

Chitin 및 그 유도체(chitosan, glucosamine)의 YPD 배지에서 알콜발효력을 비교한 결과, 대조구에 비하여 모든 첨가구간에서 알콜수율이 높게 나타나는 경향이었으며, 특히 chitin 첨가구간에서 가장 높았다. 타피오카의 알콜발효에 미치는 영향은 chitin 함량 0.9%, 발효 120시간째에 알콜함량 13.6%로 가장 높게 증가되었다 Chitin 첨가는 알콜수율을 증가시키며 acetaldehyde와 methanol 함량 감소 효과가 있는 것으로 나타나, 앞으로 타피오카의 무증자 알콜발효에 chitin의 이용이 상당히 기대된다.

• 한국식품과학회지
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• 제22권6호
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• pp.686-689
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• 1990

김치의 발효상태를 monitoring할 수 있는 압력측정 sensor와 감시장치를 설계, 제작하였다. 본 시스템은 밀폐형 발효관(31.5 ml)과 strain gauge 타입의 압력 sensor, 741 Op. Amp.와 ADC0809를 사용하여 제작한 신호가공 장치로 구성하였으며 퍼스널 컴퓨터와 접속하여 사용하였다. 배추김치는 플라스틱 용기에 담가 $25^{\circ}C$와 $30^{\circ}C$에서 발효시켰으며 발효상태는 김치를 넣은 발효관으로 monitoring하였다. 압력곡선 형태의 김치발효 곡선을 얻을 수 있었으며 이는 2단 압력증가 양식을 갖는 김치숙성 곡선을 보여주었다.

• 한국미생물·생명공학회지
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• 제49권2호
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• pp.201-209
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• 2021

Agarwood (Aquilaria spp) has high economic value. However, essential oil production from agarwood is a time-consuming process. Additionally, agarwood leaves have not been utilized even though they contain various bioactive ingredients. In this study, agarwood leaves were fermented using Lactobacillus plantarum ATCC 8014 with or without Stevia (4, 8, and 12%; v/v). The fermented fluid was mixed with maltodextrin (15%; w/v) and subjected to spray drying (inlet temperature, 120℃; outlet temperature, 65-70℃). The contents of polyphenols, polysaccharides, saponins, and flavonoids and the viability of L. plantarum were determined. Fermentation enhanced the levels of bioactive compounds. The contents of polyphenol (69.19 ± 4.05 mg GAE/g of sample), polysaccharide (20.75 ± 0.98 mg GE/g of sample), saponin (305.23 ± 4.21 mg OAE/g of sample), and flavonoid (7.86 ± 0.72 mg QE/g of sample), and the viability of L. plantarum (8.72 ± 0.17 log CFU/ml) were markedly upregulated in the samples containing Stevia (12%; v/v). This indicated that the supplementation of Stevia during fermentation decreases the fermentation time (9 h), upregulates bioactive compound production in agarwood leaves, enhances microencapsulation during spray drying, and increases the viability of L. plantarum under simulated gastric digestion conditions.

• Food Science and Biotechnology
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• 제14권1호
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• pp.21-27
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• 2005

To improve Dongchimi (watery radish kimchi) quality and preservation, 0, 3, 5, 10, and 15% of gatt (Brassica juncea; leaf mustard) per radish was added. Chemical characteristics were determined during fermentation at $10^{\circ}C$ for 45 days. Total acidity increased slowly by addition of gatt during initial fermentation period, and 15% treatment showed lowest total acidity. Total vitamin C content increased initially in all treatments depending on gatt content, and decreased thereafter. Period for reaching maximum value was delayed by addition of gatt. Highest total vitamin C was found in 15% treatments. In the case of reducing sugar, 5% treatment showed highest contents. Lactic, succinic, and tartaric acid contents consistently increased during fermentation, while those of malic and citric decreased. Turbidity and total solid contents of Dongchimi liquid increased in all treatments as fermentation proceeded, although the extent was rather suppressed by addition of gatt. Colorimetric lightness values decreased, while the initial increased and then decreased in redness and yellowness. Addition of gatt at above 15% weight level per radish accelerated fermentation at the later fermentation stage thus it should be avoided. Most changes in typical characteristics of fermentation were similar depending on treatments. More acceptable Dongchimi could be prepared by fermenting at 5% gatt concentration under given conditions.