혐기성 수소발효를 결합한 생물학적 2단공정의 유기성폐자원 처리 및 바이오에너지 생산

이채영,유규선,한선기 한국수소및신에너지학회 2015 한국수소 및 신에너지학회논문집 Vol.26 No.3

This study was performed to investigate the application of dark H2 fermentation to two-stage bioprocesses for organic waste treatment and energy production. We reviewed information about the two-stage bioprocesses combining dark H2 fermentation with CH4 fermentation, photo H2 fermentation, microbial fuel cells (MFCs), or microbial electrolysis cells (MECs) by using academic information databases and university libraries. Dark fermentative bacteria use organic waste as the sole source of electrons and energy, converting it into H2. The reactions related to dark H2 fermentation are rapid and do not require sunlight, making them useful for treating organic waste. However, the degradation is not complete and organic acids remain. Thus, dark H2 fermentation should be combined with a post-treatment process, such as CH4 fermentation, photo H2 fermentation, MFCs, or MECs. So far, dark H2 fermentation followed by CH4 fermentation is a promising two-stage bioprocess among them. However, if the problems of manufacturing expenses, operational cost, scale-up, and practical applications will be solved, the two-stage bioprocesses combining dark H2 fermentation with photo H2 fermentation, MFCs, or MECs have also infinite potential in organic waste treatment and energy production. This paper demonstrated the feasibility of two-stage bioprocesses combining dark H2 fermentation as a novel system for organic waste treatment and energy production.

Two Stage 발효에 의한 고산도 식초 생산

이영철,이금용,김형찬,박기범,유익제,안평욱,최춘언,손세형 한국산업미생물학회 1992 한국미생물·생명공학회지 Vol.20 No.6

산업적으로 산도 17.0% 이상의 고산도 식초를 생산하기 위하여 반연속식인 1st stage와 유가식인 2nd stage로 구성된 two stage 초산 발효를 온도 30 ℃, 교반속도 600 rpm, 통기량 0.1 vvm에서 실시하였다. 1st stage에서 초기 에탄올 농도를 50.0 g/ℓ, 잔류 에탄올 농도를 5.0 g/ℓ로 정하여 반연속적으로 초산발효를 하고, 2nd stage 에서 발효시간의 경과에 따라 에탄올을 유가식으로 첨가하여 초산발효액내의 에탄올 농도를 5.0 g/ℓ에서 10.0 g/ℓ로 유지했을 때 산도가 17.6%인 고산도 식초를 생산할 수 있었으며, 또한 이 ??의 최대 초산 생산성은 3.3 g/ℓ·hr였다. The production of vinegar containing 16.0 ∼18.0% of acetic acid was examined in two stage fermentation consisting of semi-continuous and fed-batch type. The optimum conditions were obtained when the fermentation was carried out at agitation of 600 rpm, aeration of 0.1 vvm and temperature of 30℃. The initial and residual ethanol concentration in 1st stage were 50.0 g/ℓ and 5.0 g/ℓ, respectively, and the ethanol concentration in 2nd stage was maintained from 5.0 to 10.0 g/ℓ. The maximum productivity was 3.3 g/ℓ-hr and the acidity was 17.6% after the two days of acetic acid fermentation.

Enhanced Acetoin Production by Serratia marcescens H32 Using Statistical Optimization and a Two-stage Agitation Speed Control Strategy

Jianan Sun,Liaoyuan Zhang,Ben Rao,Yunbin Han,Ju Chu,Jiawen Zhu,Yaling Shen,Dong-Zhi Wei 한국생물공학회 2012 Biotechnology and Bioprocess Engineering Vol.17 No.3

Enhanced acetoin production was carried out by Serratia marcescens H32. First, medium compositions were optimized statistically for shake flask fermentations to produce acetoin. Sucrose and corn steep liquor powder (CSLP) were identified as the most significant factors by Plackett–Burman design. The path of steepest ascent and response surface methodology were then employed to determine the optimal concentrations of the two factors. Acetoin yield was up to 41.5 g/L in flask fermentations using the optimized medium. Furthermore, the optimal medium was used to conduct fermentation experiments in a 3.7-L bioreactor. The influences of different agitation speeds on acetoin production were investigated. Based on a process analysis, a two-stage agitation speed control strategy was proposed, in which the agitation speed was controlled at 700 rpm during the first 8 h and then switched to 600 rpm. A relatively high acetoin concentration (44.9 g/L)and high acetoin productivity (1.73 g/L/h) were achieved by applying this strategy. Fed-batch fermentation based on the two-stage agitation speed control strategy was performed,and a maximum acetoin concentration of 60.5 g/L with productivity of 1.44 g/L/h was achieved. Enhanced acetoin production was carried out by Serratia marcescens H32. First, medium compositions were optimized statistically for shake flask fermentations to produce acetoin. Sucrose and corn steep liquor powder (CSLP) were identified as the most significant factors by Plackett–Burman design. The path of steepest ascent and response surface methodology were then employed to determine the optimal concentrations of the two factors. Acetoin yield was up to 41.5 g/L in flask fermentations using the optimized medium. Furthermore, the optimal medium was used to conduct fermentation experiments in a 3.7-L bioreactor. The influences of different agitation speeds on acetoin production were investigated. Based on a process analysis, a two-stage agitation speed control strategy was proposed, in which the agitation speed was controlled at 700 rpm during the first 8 h and then switched to 600 rpm. A relatively high acetoin concentration (44.9 g/L)and high acetoin productivity (1.73 g/L/h) were achieved by applying this strategy. Fed-batch fermentation based on the two-stage agitation speed control strategy was performed,and a maximum acetoin concentration of 60.5 g/L with productivity of 1.44 g/L/h was achieved.

Two-Stage Fermentation for 2-Ketogluconic Acid Production by Klebsiella pneumoniae

( Yue Hong Sun ),( Dong Wei ),( Ji Ping Shi ),( Ljiljana Mojovi ),( Zeng Sheng Han ),( Jian Hao ) 한국미생물 · 생명공학회 2014 Journal of microbiology and biotechnology Vol.24 No.6

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.

Optimization of Pretreatment Conditions and Use of a Two-stage Fermentation Process for the Production of Ethanol from Seaweed, Saccharina japonica

Chae Hun Ra,김성구 한국생물공학회 2013 Biotechnology and Bioprocess Engineering Vol.18 No.4

Saccharina japonica (Sea tangle, Dasima), a seaweed, was fermented in order to produce bioethanol after thermal hydrogen peroxide (H2O2) hydrolysis pretreatment and enzymatic saccharification. The optimal pretreatment conditions of 1% (v/v) H2O2 (28%, Dustan Pure Chemicals Co., Ltd, Ansan, Korea) and 10% (w/v) seaweed slurry at 121oC for 60 min were determined using the Response Surface Method (RSM). A reducing sugar yield of 33.4%(w/w) and a viscosity of 520 cP were obtained. Enzymatic saccharification was then carried out; a monosaccharide concentration of 28.5 g/L with a 40.5% (w/w) theoretical yield was obtained after the addition of 2-mL Celluclast®1.5L to 100 g/L of seaweed slurry after thermal H2O2hydrolysis. Fermentation of a two-stage ethanol production was carried out using Saccharomyces cerevisiae KCCM 1129 in order to ferment glucose in the first stage, and a high level of mannitol-acclimated Pichia angophorae KCTC 17574 to ferment mannitol in the second stage. Acclimation of yeast effectively slowed the uptake of sugar in ethanol fermentation. The overall ethanol yield from S. japonica after the two-stage fermentation was 9.9 g/L.

2단계 발효에 의한 포도식초와 재래식 포도식초의 품질 비교

정용진,이명희,서권일,김주남,이용수 동아시아식생활학회 1998 동아시아식생활학회지 Vol.8 No.4

Grape vinegar(A) and grape onion vinegar(B) added (3% of onion juice) were produced through two stages of fermentation(alcohol fermentation and acetic acid fermentation) to increase the grape's use. Grape wine which contained 5.6% alcohol was produced on the 3rd day of first stage. Then through the second stages, grape vinegar, of which total acidity was 5.37% was produced. The quality of (A) and (B) which was produced through the two stages of fermentation was compared with the traditional grape vinegar(C,D) in the market. The content of sugar in (D) was a little higher such as 5.4 °Brix than others. That of (A) and (B) was 5.13, 4.98 °Brix respectively. The content of remaining alcohol in (C) was high such as 0.23% comparatively, But there was no remaining alcohol in (A) and (B). The content of acetic acid was 4.3~5.3% as a major organic acid of vinegars. The content of tartaric acid was 340.0 in (A), 316.7 in (B), 322.6 in (C) and 391.7㎎% in (D). The content of lactic acid was distinctly high such as 277.4㎎% in (D). There were differences such as 9.2~15.5㎎% in the content of total free amino acids among grape vinegars. (D) contained 15.5㎎% of total free amino acid and (B) also highly such as 12.0㎎%. Potassium was high in grape vinegars. The content of potassium, sodium and copper was higher in (A) than (B).

Nutrient Removal Using Fermented Organic Acids Derived from the Primary Sludge in the Intermittent Aeration Activated Sludge Process

Seung Yeon Weon,Sang Il Lee,Chan Won Lee 대한환경공학회 2011 Environmental Engineering Research Vol.16 No.4

The two-stage intermittent aeration activated sludge process (IAP) and dynamic-flow intermittent aeration activated sludge process (DFP) were investigated for the nutrient removal of domestic wastewater. Three sets of IAP and one set of DFP were operated. The fermented settled sludge taken from the primary settling tank was added to two IAP and one DFP as an external electron donor, with one IAP, in which an external carbon source was not added, as a control. All the systems were operated at a sludge retention time of 20 days and a hydraulic retention time of 12 hr. A Higher denitrification rate was observed with the fermented settled sludge for the denitrification compared to the process without the addition of the organic source. The result indicates that the fermented acid from the primary domestic sludge has been proved to be an excellent electron donor for denitrification and biological phosphorus removal with IAP and DFP in treating relatively low C/N ratio(Carbon / Nitrogen ratio) wastewater. Phosphate accumulating organisms have a capability of competing with denitrifiers in the presence of volatile organic acids under anoxic conditions.

Continuous fermentative butyric acid and acetic acid production from Laminaria japonica using a two-stage fermentation system

XU XU,Ji-Young KIM,Min-Woo LEE,Jong-Moon PARK 한국생물공학회 2013 한국생물공학회 학술대회 Vol.2013 No.4

2단계 발효로 제조된 고산도 사과식초의 품질지표성분 설정

조윤희(Yunhee Jo),박윤지(Yunji Park),이현규(Hyun-Gyu Lee),이혜진(Hye-Jin Lee),정용진(Yong-Jin Jeong),여수환(Soo-Hwan Yeo),권중호(Joong-Ho Kwon) 한국식품과학회 2015 한국식품과학회지 Vol.47 No.4

In this study, high-acidity cider vinegar (HACV) was produced by alcoholic and acetic acid fermentation of apple concentrate without any nutrients and then the optimum alcohol concentration was determined through a qualitative study. HACV was fermented with different initial alcohol concentrations (6-9%) during the process of acetic acid fermentation. The highest content of reducing sugar, organic acids, and free amino acids was observed at 6% of initial alcohol concentration. Approximately 20 types of volatile compounds were identified by solid-phase microextraction (SPME) and GC-MS. The total volatile content was the highest at 6% of initial alcohol concentration, and the acid content was the lowest at 9% of the initial alcohol concentration. The HACV produced by a two-stage fermentation process was qualitatively better than commercial HACV presenting the highest value at 6% of initial alcohol concentration. Malic acid, aspartic acid, and hexyl acetate were selected as quality index components of HACV production by two-stage fermentation on the basis of correlation between their physicochemical properties and the sensory attributes of HACV.

상이한 재료로 제조된 자연발효식초의 품질특성 비교

박연옥(Yeon-Ok Park) 한국식품영양과학회 2018 한국식품영양과학회지 Vol.47 No.1

본 연구는 상이한 재료를 이용한 4종의 자연발효식초를 2단계 발효법으로 제조하여 각 식초의 이화학적 품질특성과 항산화 활성을 비교하여 기능성 발효식초의 품질향상을 위한 기초자료를 제공하고자 실시하였다. 각 식초의 pH, 총산도, 당도, 색도, 아미노산 함량, 총 폴리페놀 및 플라보노이드 함량, 폴리페놀 성분, DPPH 라디칼 소거능 등을 분석하였다. 3종의 현미식초는 pH 3.3~3.4, 총산도 4.1~5.1%로 유의적으로 차이를 보였으며 전체적으로 저산도 식초였다. 당도는 해초현미식초가 유의적으로 가장 높았으며(P<0.05), 현미식초의 명도가 가장 높았고 적색도는 배흑미식초, 황색도는 해초현미식초가 높아 식초 제조 시 첨가한 재료에 따라 유의적인 차이(P<0.05)를 보였다. 필수아미노산 함량은 울금현미식초의 valine, leucine, lysine, threonine 등이 유의적인 차이를 보이며 가장 많았고 전반적으로 현미식초가 배흑미식초보다 더 많이 함유하였다. 비필수아미노산은 전체적으로 aspartic acid와 glutamic acid의 함량이 많았으며, aspartic acid는 해초현미식초가 38.7 mg/100 mL로 유의적으로 가장 많았고 glutamic acid는 울금현미식초가 128.1 mg/100 mL로 가장 많았다(P<0.05). 총 폴리페놀 함량은 유의적으로 울금현미식초가 54.7 mg GAE/100 mL로 가장 많았으며 해초현미식초가 48.4 mg GAE/100 mL로 다음 순이었다. 총 플라보노이드 함량은 배흑미식초가 9.09 mg CE/100 mL로 가장 많았고 현미식초가 0.62 mg CE/100 mL로 현저하게 낮았다. 폴리페놀 성분은 해초현미식초의 protocatechuic acid, caffeic acid, coumaric acid 등이 유의적으로 가장 많았고 재료에 따라 성분의 함량은 차이를 보였다. DPPH 라디칼 소거 활성은 총 폴리페놀 함량과 비례하여 울금현미식초의 소거 활성이 76%로 유의적으로 가장 높았으며 배흑미식초, 해초현미식초, 현미식초 순이었다(P<0.05). 즉 각 식초에 함유한 총 폴리페놀 함량에 따라 DPPH 라디칼 소거 활성이 차이를 보였다. 결론적으로 상이한 재료를 이용하고 전통적인 2단계 발효법으로 제조한 4종의 자연발효식초 모두 품질특성이 우수하지만, 특히 울금현미식초는 저산도 식초로서 아미노산 함량도 풍부하고 총 폴리페놀 및 플라보노이드 성분과 함량이 많아서 DPPH 라디칼 소거활성 등 항산화 활성이 우수하여 조미용뿐만 아니라 음료용으로 폭넓게 산업화로 개발한다면 국민건강 향상을 위한 새로운 기능성 식초로서 활용도가 높을 것으로 생각된다. This study was performed to evaluate the quality characteristics of four kinds of natural fermented vinegars manufactured with different raw materials (PBV, pear black rice vinegar; BRV, brown rice vinegar; CBV, curcuma root brown rice vinegar; SBV, sea grass brown rice vinegar), including pH, total acidity, color, contents of sugar, amino acids, total polyphenols, total flavonoids, polyphenolic compounds, and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity. The total acidity of vinegars was significantly different and ranged from 4.1∼5.1% (P<0.05). L, a, and b values were the highest in BRV, PBV, and SBV, respectively. Among the four vinegars, essential amino acids were the highest in CBV in the order of valine, leucine, lysine, and threonine. Additionally, four kinds of natural fermented vinegars have many non-essential amino acids such as aspartic acid and glutamic acid. Aspartic acid content was highest in SBV while glutamic acid content was highest in CBV. The total polyphenol content was highest in CBV while total flavonoid content was highest in PBV. Polyphenolic compounds such as protocatechuic acid, caffeic acid, and coumaric acid were highest in SBV. DPPH radical scavenging activity (%) was the highest in CBV. These results show that CBV manufactured using two-stage fermentation would be desirable to prepare high-quality vinegars and functional foods.